Version bump

Commentary
Turn off parser debug in optimized build, msg2203
2026-10-03 08:33:21 +02:00 · 2017-04-02 08:43:53 -04:00 · 2017-04-02 08:39:33 -04:00 · 2017-03-31 17:46:15 -04:00 · 2017-03-30 19:05:55 -04:00 · 2017-03-30 18:32:37 -04:00
534 changed files with 14317 additions and 5788 deletions
@@ -1,9 +1,257 @@
 Revision history for Verilator

-The contributors that suggested a given feature are shown in [].  [by ...]
-indicates the contributor was also the author of the fix; Thanks!
+The contributors that suggested a given feature are shown in []. Thanks!

-* Verilator 3.873 2015-06-06
+
+* Verilator 3.902 2017-04-02
+
+**    Add -FI option to force includes,msg2146. [Amir Gonnen]
+
+**    Add --relative-includes. [Rob Stoddard]
+
+***   Add error on duplicate pattern assignments, bug1145. [Johan Bjork]
+
+****  Fix error on improperly widthed default function, bug984. [Todd Strader]
+
+****  Fix 2009 localparam syntax, msg2139. [Galen Seitz]
+
+****  Fix ugly interface-to-non-interface errors, bug1112. [Johan Bjork]
+
+****  Fix LDFLAGS and CFLAGS not preserving order, bug1130. [Olof Kindgren]
+
+****  Fix internal error on initializing parameter array, bug1131. [Jie Xu]
+
+****  Fix internal error on interface arrays, bug1135. [John Stevenson]
+
+****  Fix calling sformatf to display, and elab $displays, bug1139. [Johan Bjork]
+
+****  Fix realpath compile issue on MSVC++, bug1141. [Miodrag Milanovic]
+
+****  Fix missing error on interface size mismatch, bug1143.  [Johan Bjork]
+
+****  Fix error on parameters with dotted references, bug1146. [Johan Bjork]
+
+****  Fix wreal not handling continuous assign, bug1150. [J Briquet]
+
+****  Fix nested structure parameter selects, bug1150. [J Briquet]
+
+
+* Verilator 3.900 2017-01-15
+
+**    Internal code changes for improved compatibility and performance.
+
+***   Support old-style $display($time), bug467. [John Demme]
+
+****  With --bbox-unsup, suppress desassign and mixed edges, bug1120. [Galen Seitz]
+
+****  Fix parsing sensitivity with &&, bug934. [Luke Yang]
+
+****  Fix internal error on double-for loop unrolling, bug1044. [Jan Egil Ruud]
+
+****  Fix internal error on unique casez with --assert, bug1117. [Enzo Chi]
+
+****  Fix bad code when tracing array of structs, bug1122. [Andrew Bardsley]
+
+
+* Verilator 3.890 2016-11-25
+
+***   Honor --output-split on coverage constructors, bug1098. [Johan Bjork]
+
+****  Fix various issues when making outside of the kit.
+
+****  Fix flex 2.6.2 bug, bug1103. [Sergey Kvachonok]
+
+****  Fix error on bad interface name, bug1097. [Todd Strader]
+
+****  Fix error on referencing variable in parent, bug1099. [Ian Thompson]
+
+****  Fix type parameters with low optimization, bug1101. [Stefan Wallentowitz]
+
+
+* Verilator 3.888 2016-10-14
+
+**    Support foreach, bug1078. [Xuan Guo]
+
+***   Add --no-decoration to remove output comments, msg2015. [Frederic Requin]
+
+***   If VM_PARALLEL_BUILDS=1, use OPT_FAST and OPT_SLOW. [Frederic Requin]
+      Set VM_DEFAULT_RULES=0 for old behavior.
+
+****  Add error on DPI functions > 32 bits, msg1995. [Elliot Mednick]
+
+****  Fix SystemC compiles with VPI, bug1081. [Arthur Kahlich]
+
+****  Fix error on wide numbers that represent shifts, msg1991, bug1088. [Mandy Xu]
+
+****  Improve Verilation performance on internal strings, msg1975. [Johan Bjork]
+
+****  Improve Verilation performance on trace duplicates, bug1090. [Johan Bjork]
+
+
+* Verilator 3.886 2016-07-30
+
+****  Fix enum values of 11-16 bits wide using .next/.prev, bug1062. [Brian Flachs]
+
+****  Fix false warnings on non-power-2 enums using .next/.prev.
+
+****  Fix comparison of unpacked arrays, bug1071. [Andrew Bardsley]
+
+****  Fix compiler warning in GCC 6. [David Horton]
+
+
+* Verilator 3.884 2016-05-18
+
+**    Support parameter type, bug376. [Alan Hunter, et al]
+
+**    Support command-line -G/+pvalue param overrides, bug1045. [Stefan Wallentowitz]
+
+***   The default l2 scope name is now the same as the top-level module, bug1050.
+      Use "--l2-name v" for the historical behavior.
+
+***   Add --l2-name option for controlling "v" naming.
+
+****  Fix --output-split of constructors, bug1035. [Johan Bjork]
+
+****  Fix removal of empty packages, modules and cells, bug1034. [Johan Bjork]
+
+****  Fix core dump on Arch Linux/GCC 6.1.1, bug1058. [Jannis Harder]
+
+****  Fix $value$plusargs to string, msg1890. [Frederic Requin]
+
+
+* Verilator 3.882 2016-03-01
+
+****  Internal Verilation-time performance enhancements, bug1021. [Johan Bjork]
+
+****  Support inlining interfaces, bug1018. [Johan Bjork]
+
+****  Support SV strings to readmemh, bug1040. [Stefan Wallentowitz]
+
+****  Fix unrolling complicated for-loop bounds, bug677. [Johan Bjork]
+
+****  Fix stats file containing multiple unroll entries, bug1020. [Johan Bjork]
+
+****  Fix using short parameter names on negative params, bug1022. [Duraid Madina]
+
+****  Fix read-after-free error, bug1031. [Johan Bjork]
+
+****  Fix elaboration-time display warnings, bug1032. [Johan Bjork]
+
+****  Fix crash on very deep function trees, bug1028. [Jonathan Kimmitt]
+
+****  Fix slicing mix of big and little-endian, bug1033. [Geoff Barrett]
+
+****  Fix pattern assignment width propagation, bug1037. [Johan Bjork]
+
+
+* Verilator 3.880 2015-12-19
+
+***   Support display %u, %v, %p, %z, bug989. [Johan Bjork]
+
+****  Fix real parameters causing bad module names, bug992. [Johan Bjork]
+
+****  Fix size-changing cast on packed struct, bug993. [Johan Bjork]
+
+****  Fix function calls on arrayed interface, bug994. [Johan Bjork]
+
+****  Fix arrayed interfaces, bug879, bug1001. [Todd Strader]
+
+****  Fix constant function assigned to packed structs, bug997. [Johan Bjork]
+
+****  Fix interface inside generate, bug998. [Johan Bjork]
+
+****  Fix $signed casts under generates, bug999. [Clifford Wolf]
+
+****  Fix genvar constant propagation, bug1003. [Johan Bjork]
+
+****  Fix parameter constant propagation from package, bug1004. [Johan Bjork]
+
+****  Fix array slicing of non-const indexes, bug1006. [Johan Bjork]
+
+****  Fix dotted generated array error, bug1005. [Jeff Bush, Johan Bjork]
+
+****  Fix error instead of warning on large concat, msg1768. [Paul Rolfe]
+
+****  Fix $bitstoreal constant propagation, bug1012. [Jonathan Kimmitt]
+
+****  Fix model restore crash, bug1013. [Jason McMullan]
+
+****  Fix arrayed instances to unpacked of same size, bug1015. [Varun Koyyalagunta]
+
+****  Fix slices of unpacked arrays with non-zero LSBs.
+
+****  Fix ternary operation with unpacked array, bug1017. [Varun Koyyalagunta].
+
+
+* Verilator 3.878 2015-11-01
+
+**    Add --vpi flag, and fix VPI linkage, bug969. [Arthur Kahlich]
+
+**    Support genvar indexes into arrayed cells, bug517.  [Todd Strader]
+
+**    Support $sformatf, bug977. [Johan Bjork]
+
+***   Support elaboration assertions, bug973. [Johan Bjork]
+
+***   Support $display with non-format arguments, bug467. [Jamey Hicks]
+
+****  Add VerilatedScopeNameMap for introspection, bug966. [Todd Strader]
+
+****  Ignore %l in $display, bug983. [Todd Strader]
+
+****  Fix very long module names, bug937. [Todd Strader]
+
+****  Fix internal error on dotted refs into generates, bug958. [Jie Xu]
+
+****  Fix structure parameter constant propagation, bug968. [Todd Strader]
+
+****  Fix enum constant propagation, bug970. [Todd Strader]
+
+****  Fix mis-optimizing public DPI functions, bug963. [Wei Song]
+
+****  Fix package:scope.scope variable references.
+
+****  Fix $fwrite to constant stderr/stdout, bug961. [Wei Song]
+
+****  Fix struct.enum.name method calls, bug855. [Jonathon Donaldson]
+
+****  Fix dot indexing into arrayed inferfaces, bug978.  [Johan Bjork]
+
+****  Fix crash in commandArgsPlusMatch, bug987. [Jamie Iles]
+
+****  Fix error message on missing interface, bug985. [Todd Strader]
+
+
+* Verilator 3.876 2015-08-12
+
+***   Add tracing_on, etc to vlt files, bug932. [Frederic Requin]
+
+****  Support extraction of enum bits, bug951. [Jonathon Donaldson]
+
+****  Fix MinGW compiler error, bug927, bug929. [Hans Tichelaar]
+
+****  Fix .c files to be treated as .cpp, bug930. [Jonathon Donaldson]
+
+****  Fix string-to-int space conversion, bug931. [Fabrizio Ferrandi]
+
+****  Fix dpi imports inside generates. [Michael Tresidder]
+
+****  Fix rounding in trace $timescale, bug946. [Frederic Requin]
+
+****  Fix $fopen with SV string, bug947. [Sven Stucki]
+
+****  Fix hashed error with typedef inside block, bug948. [Sven Stucki]
+
+****  Fix makefile with --coverage, bug953. [Eivind Liland]
+
+****  Fix coverage documentation, bug954. [Thomas J Whatson]
+
+****  Fix parameters with function parameter arguments, bug952. [Jie Xu]
+
+****  Fix size casts as second argument of cast item, bug950. [Jonathon Donaldson]
+
+
+* Verilator 3.874 2015-06-06

 ***   Add pkg-config .pc file, bug919. [Stefan Wallentowitz]

@@ -2572,12 +2820,12 @@ of input ports exists for tracing.

 This uses outline mode in Emacs.  See C-h m [M-x describe-mode].

-Copyright 2001-2015 by Wilson Snyder.  This program is free software; you
+Copyright 2001-2017 by Wilson Snyder.  This program is free software; you
 can redistribute it and/or modify it under the terms of either the GNU
 Lesser General Public License Version 3 or the Perl Artistic License
 Version 2.0.

 Local variables:
 mode: outline
-paragraph-separate: "[ 	\f\n]*$"
+paragraph-separate: "[  \f\n]*$"
 end:
@@ -7,7 +7,7 @@
 #
 #*****************************************************************************
 #
-# Copyright 2003-2015 by Wilson Snyder. This program is free software; you can
+# Copyright 2003-2017 by Wilson Snyder. This program is free software; you can
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
@@ -42,9 +42,6 @@
 #      reconstructed with this Makefile.  This typically includes
 #      everything deleted by distclean, plus more: C source files
 #      produced by Bison, tags tables, info files, and so on.
-#
-# make extraclean
-#      Still more severe - delete backup and autosave files, too.

 #### Start of system configuration section. ####

@@ -71,7 +68,7 @@ exec_prefix = @exec_prefix@
 # Directory in which to install scripts.
 bindir = @bindir@

-# Directory in which to install scripts.
+# Directory in which to install manpages.
 mandir = @mandir@

 # Directory in which to install library files.
@@ -100,6 +97,8 @@ PACKAGE_VERSION = @PACKAGE_VERSION@
 #### End of system configuration section. ####
 ######################################################################

+.SUFFIXES:
+
 SHELL = /bin/sh

 SUBDIRS = src test_verilated test_c test_sc test_regress
@@ -133,6 +132,8 @@ DISTFILES_INC = $(INFOS) .gitignore Artistic COPYING COPYING.LESSER \
 	test_verilated/vgen*.pl \
 	test_regress/t/t*/*.sv* \
 	test_regress/t/t*/*.v* \
+	test_regress/t/t*/*/*.sv* \
+	test_regress/t/t*/*/*.v* \
 	test_regress/t/*.cpp \
 	test_regress/t/*.h \
 	test_regress/t/*.dat \
@@ -271,6 +272,7 @@ VL_INST_BIN_FILES = verilator verilator_bin verilator_bin_dbg verilator_coverage
 VL_INST_MAN_FILES = verilator.1 verilator_coverage.1 verilator_profcfunc.1

 VL_INST_INC_BLDDIR_FILES = \
+	include/verilated_config.h \
 	include/verilated.mk \

 # Files under srcdir, instead of build time
@@ -298,7 +300,8 @@ installbin:
 # So important we use $< so VPATH is searched
 installman: $(VL_INST_MAN_FILES)
 	$(SHELL) ${srcdir}/mkinstalldirs $(DESTDIR)$(mandir)/man1
-	for p in $^ ; do \
+	cd $(srcdir) \
+	; for p in $(VL_INST_MAN_FILES) ; do \
 	  $(INSTALL_DATA) $$p $(DESTDIR)$(mandir)/man1/$$p; \
 	done

@@ -11,7 +11,7 @@ This is the Verilator package README file.

 http://www.veripool.org/verilator

-This package is Copyright 2003-2015 by Wilson Snyder.  (Report bugs to
+This package is Copyright 2003-2017 by Wilson Snyder.  (Report bugs to
 L<http://www.veripool.org/>.)

 Verilator is free software; you can redistribute it and/or modify it under
@@ -117,9 +117,10 @@ and add it to path using Modules/modulecmd:
    After installing you'll want a module file like the following:

    set install_root /CAD_DISK/verilator/{version-number-used-above}
-    setenv VERILATOR_ROOT $install_root
+    unsetenv VERILATOR_ROOT
    prepend-path PATH $install_root/bin
    prepend-path MANPATH $install_root/man
+    prepend-path PKG_CONFIG_PATH $install_root/share/pkgconfig

 =item 3.

@@ -1,6 +1,6 @@
 // DESCRIPTION: Verilator: List of To Do issues.
 //
-// Copyright 2004-2015 by Wilson Snyder. This program is free software; you can
+// Copyright 2004-2017 by Wilson Snyder. This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -3,7 +3,7 @@ eval 'exec perl -wS $0 ${1+"$@"}'
  if 0;
 ######################################################################
 #
-# Copyright 2003-2015 by Wilson Snyder. This program is free software; you
+# Copyright 2003-2017 by Wilson Snyder. This program is free software; you
 # can redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
@@ -19,8 +19,8 @@ require 5.006_001;
 use warnings;
 BEGIN {
    if ($ENV{DIRPROJECT} && $ENV{DIRPROJECT_PERL_BOOT}) {
-	# Magic to allow author testing of perl packages in local directory
-	require $ENV{DIRPROJECT}."/".$ENV{DIRPROJECT_PERL_BOOT};
+        # Magic to allow author testing of perl packages in local directory
+        require $ENV{DIRPROJECT}."/".$ENV{DIRPROJECT_PERL_BOOT};
    }
 }

@@ -54,22 +54,33 @@ push @ARGV, (split ' ',$ENV{VERILATOR_TEST_FLAGS}||"");
 # We sneak a look at the flags so we can do some pre-environment checks
 # All flags will hit verilator...
 foreach my $sw (@ARGV) {
-    $sw = "'$sw'" if $sw =~ m![^---a-zA-Z0-9_/\\:.+]!;
+    # Some special treatment for parameters to allow verilog literals for numbers
+    if ((substr($sw, 0, 2) eq "-G") || (substr($sw, 0, 8) eq "-pvalue+")) {
+        # If there is a single quote in the parameter put it double quotes ,
+        # else just put it in double quotes
+        if ($sw =~ m![\']!) {
+            $sw = "\"$sw\"";
+        } else {
+            $sw = "'$sw'";
+        }
+    } else {
+        $sw = "'$sw'" if $sw =~ m![^---a-zA-Z0-9_/\\:.+]!;
+    }
    push @Opt_Verilator_Sw, $sw;
 }

 Getopt::Long::config ("no_auto_abbrev","pass_through");
 if (! GetOptions (
-		  # Major operating modes
-		  "help"	=> \&usage,
-		  "debug:s"	=> \&debug,
-		  # "version!"	=> \&version,	# Also passthru'ed
-		  # Switches
-		  "gdb!"	=> \$opt_gdb,
-		  "gdbbt!"	=> \$opt_gdbbt,
-		  # Additional parameters
-		  "<>"		=> sub {},	# Ignored
-		  )) {
+                  # Major operating modes
+                  "help"        => \&usage,
+                  "debug:s"     => \&debug,
+                  # "version!"  => \&version,   # Also passthru'ed
+                  # Switches
+                  "gdb!"        => \$opt_gdb,
+                  "gdbbt!"      => \$opt_gdbbt,
+                  # Additional parameters
+                  "<>"          => sub {},      # Ignored
+                  )) {
    pod2usage(-exitstatus=>2, -verbose=>0);
 }

@@ -81,22 +92,22 @@ if ($opt_gdbbt && !gdb_works()) {
 if ($opt_gdb) {
    # Generic GDB interactive
    run (("gdb"||$ENV{VERILATOR_GDB})
-	 ." ".verilator_bin()
-	 ." -ex 'run ".join(' ',@Opt_Verilator_Sw)."'"
-	 ." -ex 'set width 0'"
-	 ." -ex 'bt'");
+         ." ".verilator_bin()
+         ." -ex 'run ".join(' ',@Opt_Verilator_Sw)."'"
+         ." -ex 'set width 0'"
+         ." -ex 'bt'");
 } elsif ($opt_gdbbt && $Debug) {
    # Run under GDB to get gdbbt
    run ("gdb"
-	 ." ".verilator_bin()
-	 ." --batch --quiet --return-child-result"
-	 ." -ex 'run ".join(' ',@Opt_Verilator_Sw)."'"
-	 ." -ex 'set width 0'"
-	 ." -ex 'bt'");
+         ." ".verilator_bin()
+         ." --batch --quiet --return-child-result"
+         ." -ex 'run ".join(' ',@Opt_Verilator_Sw)."'"
+         ." -ex 'set width 0'"
+         ." -ex 'bt'");
 } else {
    # Normal, non gdb
    run (verilator_bin()
-	 ." ".join(' ',@Opt_Verilator_Sw));
+         ." ".join(' ',@Opt_Verilator_Sw));
 }

 #----------------------------------------------------------------------
@@ -119,23 +130,23 @@ sub verilator_bin {
    my $bin = "";
    # Use VERILATOR_ROOT if defined, else assume verilator_bin is in the search path
    my $basename = ($ENV{VERILATOR_BIN}
-		    || ($Debug ? "verilator_bin_dbg" : "verilator_bin"));
+                    || ($Debug ? "verilator_bin_dbg" : "verilator_bin"));
    if (defined($ENV{VERILATOR_ROOT})) {
-	my $dir = $ENV{VERILATOR_ROOT};
-	if (-x "$dir/bin/$basename") {  # From a "make install" into VERILATOR_ROOT
-	    $bin = "$dir/bin/$basename";
-	} else {
-	    $bin = "$dir/$basename";  # From pointing to kit directory
-	}
+        my $dir = $ENV{VERILATOR_ROOT};
+        if (-x "$dir/bin/$basename") {  # From a "make install" into VERILATOR_ROOT
+            $bin = "$dir/bin/$basename";
+        } else {
+            $bin = "$dir/$basename";  # From pointing to kit directory
+        }
    } else {
-	if (-x "$RealBin/$basename") {
-	    $bin = "$RealBin/$basename";  # From path/to/verilator with verilator_bin installed
-	} else {
-	    $bin = $basename;  # Find in PATH
-	}
-	# Note we don't look under bin/$basename which would be right if running
-	# in the kit dir. Running that would likely break, since
-	# VERILATOR_ROOT wouldn't be set and Verilator won't find internal files.
+        if (-x "$RealBin/$basename") {
+            $bin = "$RealBin/$basename";  # From path/to/verilator with verilator_bin installed
+        } else {
+            $bin = $basename;  # Find in PATH
+        }
+        # Note we don't look under bin/$basename which would be right if running
+        # in the kit dir. Running that would likely break, since
+        # VERILATOR_ROOT wouldn't be set and Verilator won't find internal files.
    }
    return $bin;
 }
@@ -147,10 +158,10 @@ sub verilator_bin {
 sub gdb_works {
    $! = undef;  # Cleanup -x
    system("gdb /bin/echo"
-	   ." --batch-silent --quiet --return-child-result"
-	   ." -ex 'run -n'"  # `echo -n`
-	   ." -ex 'set width 0'"
-	   ." -ex 'bt'");
+           ." --batch-silent --quiet --return-child-result"
+           ." -ex 'run -n'"  # `echo -n`
+           ." -ex 'set width 0'"
+           ." -ex 'bt'");
    my $status = $?;
    return $status==0;
 }
@@ -163,23 +174,23 @@ sub run {
    system($command);
    my $status = $?;
    if ($status) {
-	if ($! =~ /no such file or directory/i) {
-	    warn "%Error: verilator: Misinstalled, or VERILATOR_ROOT might need to be in environment\n";
-	}
-	if ($Debug) {  # For easy rerunning
-	    warn "%Error: export VERILATOR_ROOT=".($ENV{VERILATOR_ROOT}||"")."\n";
-	    warn "%Error: $command\n";
-	}
-	if ($status & 127) {
-	    if (($status & 127) == 8 || ($status & 127) == 11) { # SIGFPA or SIGSEGV
-		warn "%Error: Verilator internal fault, sorry.  Consider trying --debug --gdbbt\n" if !$Debug;
-	    } elsif (($status & 127) == 6) {  # SIGABRT
-		warn "%Error: Verilator aborted.  Consider trying --debug --gdbbt\n" if !$Debug;
-	    } else {
-		warn "%Error: Verilator threw signal $status.  Consider trying --debug --gdbbt\n" if !$Debug;
-	    }
-	}
-	die "%Error: Command Failed $command\n";
+        if ($! =~ /no such file or directory/i) {
+            warn "%Error: verilator: Misinstalled, or VERILATOR_ROOT might need to be in environment\n";
+        }
+        if ($Debug) {  # For easy rerunning
+            warn "%Error: export VERILATOR_ROOT=".($ENV{VERILATOR_ROOT}||"")."\n";
+            warn "%Error: $command\n";
+        }
+        if ($status & 127) {
+            if (($status & 127) == 8 || ($status & 127) == 11) { # SIGFPA or SIGSEGV
+                warn "%Error: Verilator internal fault, sorry.  Consider trying --debug --gdbbt\n" if !$Debug;
+            } elsif (($status & 127) == 6) {  # SIGABRT
+                warn "%Error: Verilator aborted.  Consider trying --debug --gdbbt\n" if !$Debug;
+            } else {
+                warn "%Error: Verilator threw signal $status.  Consider trying --debug --gdbbt\n" if !$Debug;
+            }
+        }
+        die "%Error: Command Failed $command\n";
    }
 }

@@ -198,9 +209,9 @@ Verilator - Convert Verilog code to C++/SystemC

    verilator --help
    verilator --version
-    verilator --cc [options] [top_level.v]... [opt_c_files.cpp/c/cc/a/o/so]
-    verilator --sc [options] [top_level.v]... [opt_c_files.cpp/c/cc/a/o/so]
-    verilator --lint-only    [top_level.v]...
+    verilator --cc [options] [source_files.v]... [opt_c_files.cpp/c/cc/a/o/so]
+    verilator --sc [options] [source_files.v]... [opt_c_files.cpp/c/cc/a/o/so]
+    verilator --lint-only    [source_files.v]...

 =head1 DESCRIPTION

@@ -228,7 +239,7 @@ To get started, jump down to "EXAMPLE C++ EXECUTION".
 This is a short summary of the arguments to Verilator.  See the detailed
 descriptions in the next sections for more information.

-    {file.v}                    Verilog top level filenames
+    {file.v}                    Verilog package, module and top module filenames
    {file.c/cc/cpp}             Optional C++ files to compile in
    {file.a/o/so}               Optional C++ files to link in

@@ -269,6 +280,8 @@ descriptions in the next sections for more information.
    --exe                       Link to create executable
     -F <file>                  Parse options from a file, relatively
     -f <file>                  Parse options from a file
+     -FI <file>                 Force include of a file
+     -G<name>=<value>           Overwrite toplevel parameter
    --gdb                       Run Verilator under GDB interactively
    --gdbbt                     Run Verilator under GDB for backtrace
    --help                      Display this help
@@ -279,6 +292,7 @@ descriptions in the next sections for more information.
    --inline-mult <value>       Tune module inlining
     -LDFLAGS <flags>           Linker pre-object flags for makefile
     -LDLIBS <flags>            Linker library flags for makefile
+    --l2-name <value>           Verilog scope name of the top module
    --language <lang>           Default language standard to parse
     +libext+<ext>+[ext]...     Extensions for finding modules
    --lint-only                 Lint, but do not make output
@@ -287,6 +301,7 @@ descriptions in the next sections for more information.
    --Mdir <directory>          Name of output object directory
    --mod-prefix <topname>      Name to prepend to lower classes
    --no-clk <signal-name>      Prevent marking specified signal as clock
+    --no-decoration             Disable comments and symbol decorations
    --no-pins64                 Don't use vluint64_t's for 33-64 bit sigs
    --no-skip-identical         Disable skipping identical output
     +notimingchecks            Ignored
@@ -308,8 +323,10 @@ descriptions in the next sections for more information.
    --profile-cfuncs            Name functions for profiling
    --private                   Debugging; see docs
    --public                    Debugging; see docs
+     -pvalue+<name>=<value>     Overwrite toplevel parameter
+    --relative-includes         Resolve includes relative to current file
    --report-unoptflat          Extra diagnostics for UNOPTFLAT
-    --savable			Enable model save-restore
+    --savable                   Enable model save-restore
    --sc                        Create SystemC output
    --stats                     Create statistics file
    --stats-vars                Provide statistics on variables
@@ -331,6 +348,7 @@ descriptions in the next sections for more information.
     -v <filename>              Verilog library
     +verilog1995ext+<ext>      Synonym for +1364-1995ext+<ext>
     +verilog2001ext+<ext>      Synonym for +1364-2001ext+<ext>
+    --vpi                       Enable VPI compiles
     -Werror-<message>          Convert warning to error
     -Wfuture-<message>         Disable unknown message warnings
     -Wno-<message>             Disable warning
@@ -428,9 +446,10 @@ calls.

 =item --bbox-unsup

-Black box some unsupported language features, currently UDP tables and the
-cmos and tran gate primitives.  This may enable linting the rest of the
-design even when unsupported constructs are present.
+Black box some unsupported language features, currently UDP tables, the
+cmos and tran gate primitives, deassign statements, and mixed edge errors.
+This may enable linting the rest of the design even when unsupported
+constructs are present.

 =item --bin I<filename>

@@ -471,14 +490,14 @@ Verilator will mark the signal as clocker and propagate the clocker attribute
 automatically to other signals derived from that. In this way, Verilator will
 try to avoid taking the clocker signal into checking list.

-Note signal-name is specified by the RTL hiearchy path. For example, v.foo.bar.
+Note signal-name is specified by the RTL hierarchy path. For example, v.foo.bar.
 If the signal is the input to top-module, the directly the signal name. If you
 find it difficult to find the exact name, try to use C</*verilator clocker*/> in
 RTL file to mark the signal directly.

 =item --compiler I<compiler-name>

-Enables tunings and work-arounds for the specified C++ compiler.
+Enables tunings and workarounds for the specified C++ compiler.

 =over 4

@@ -591,8 +610,8 @@ alias for GCC compatibility.
 =item --debug

 Select the debug built image of Verilator (if available), and enable more
-internal assertions (equivelent to C<--debug-check>), debugging messages
-(equivelent to C<--debugi 4>), and intermediate form dump files (equivilent
+internal assertions (equivalent to C<--debug-check>), debugging messages
+(equivalent to C<--debugi 4>), and intermediate form dump files (equivalent
 to C<--dump-treei 3>).

 =item --debug-check
@@ -687,6 +706,43 @@ The file may contain // comments which are ignored to the end of the line.
 Any $VAR, $(VAR), or ${VAR} will be replaced with the specified environment
 variable.

+=item -FI <file>
+
+Force include of the specified C++ header file.  All generated C++ files
+will insert a #include of the specified file before any other includes. The
+specified file might be used to contain define prototypes of custom
+VL_VPRINTF functions, and may need to include verilatedos.h as this file is
+included before any other standard includes.
+
+=item -GI<name>=I<value>
+
+Overwrites the given parameter of the toplevel module. The value is limited
+to basic data literals:
+
+=over 4
+
+=item Verilog integer literals
+
+The standard verilog integer literals are supported, so values like 32'h8,
+2'b00, 4 etc. are allowed. Care must be taken that the single quote (I') is
+properly escaped in an interactive shell, e.g., as -GWIDTH=8\'hx.
+
+=item C integer literals
+
+It is also possible to use C integer notation, including hexadecimal (0x..),
+octal (0..) or binary (0b..) notation.
+
+=item Double literals
+
+Double literals must contain a dot (.) and/or an exponent (e).
+
+=item Strings
+
+String must in double quotes ("). On the command line it is required to escape
+them properly, e.g. as -GSTR="\"My String\"" or -GSTR='"My String"'.
+
+=back
+
 =item --gdb

 Run Verilator underneath an interactive GDB (or VERILATOR_GDB environment
@@ -742,9 +798,19 @@ called LDLIBS as that's the Makefile variable it controls.  (In Make,
 LDFLAGS is before the first object, LDLIBS after.  -L libraries need to be
 in the Make variable LDLIBS, not LDFLAGS.)

+=item --l2-name I<value>
+
+Instead of using the module name when showing Verilog scope, use the name
+provided. This allows simplifying some Verilator-embedded modeling
+methodologies. Default is an l2-name matching the top module. The default
+before 3.884 was "--l2-name v"
+
+For example, the program "module t; initial $display("%m"); endmodule" will
+show by default "t". With "--l2-name v" it will print "v".
+
 =item --language I<value>

-A synonym for C<--default-langauge>, for compatibility with other tools and
+A synonym for C<--default-language>, for compatibility with other tools and
 earlier versions of Verilator.

 =item +libext+I<ext>+I<ext>...
@@ -789,6 +855,13 @@ the same as --prefix.

 Prevent the specified signal from being marked as clock. See C<--clk>.

+=item --no-decoration
+
+When creating output Verilated code, minimize comments, whitespace, symbol
+names and other decorative items, at the cost of greatly reduced
+readability. This may assist C++ compile times. This will not typically
+change the ultimate model's performance, but may in some cases.
+
 =item --no-pins64

 Backward compatible alias for "--pins-bv 33".
@@ -872,9 +945,10 @@ Backward compatible alias for "--pins-bv 65".  Note that's a 65, not a 64.

 Specifies SystemC inputs/outputs of greater than or equal to I<width> bits
 wide should use sc_bv's instead of uint32/vluint64_t's.  The default is
-"--pins-bv 65".  Versions before Verilator 3.671 defaulted to "--pins-bv
-33".  The more sc_bv is used, the worse for performance.  Use the
-"/*verilator sc_bv*/" attribute to select specific ports to be sc_bv.
+"--pins-bv 65", and the value must be less than or equal to 65.  Versions
+before Verilator 3.671 defaulted to "--pins-bv 33".  The more sc_bv is
+used, the worse for performance.  Use the "/*verilator sc_bv*/" attribute
+to select specific ports to be sc_bv.

 =item --pins-sc-uint

@@ -945,6 +1019,17 @@ inlining.  This will also turn off inlining as if all modules had a
 /*verilator public_module*/, unless the module specifically enabled it with
 /*verilator inline_module*/.

+=item -pvalue+I<name>=I<value>
+
+Overwrites the given parameter(s) of the toplevel module. See -G for a
+detailed description.
+
+=item --relative-includes
+
+When a file references an include file, resolve the filename relative to
+the path of the referencing file, instead of relative to the current
+directory.
+
 =item --report-unoptflat

 Extra diagnostics for UNOPTFLAT warnings. This includes for each loop, the
@@ -1103,6 +1188,10 @@ Note -v is fairly standard across Verilog tools.

 Synonyms for C<+1364-1995ext+>I<ext> and C<+1364-2001ext+>I<ext> respectively

+=item --vpi
+
+Enable use of VPI and linking against the verilated_vpi.cpp files.
+
 =item -Wall

 Enable all warnings, including code style warnings that are normally
@@ -1264,7 +1353,7 @@ We'll compile this example into C++.
      #include "Vour.h"
      #include "verilated.h"
      int main(int argc, char **argv, char **env) {
-	  Verilated::commandArgs(argc, argv);
+          Verilated::commandArgs(argc, argv);
          Vour* top = new Vour;
          while (!Verilated::gotFinish()) { top->eval(); }
          delete top;
@@ -1272,9 +1361,15 @@ We'll compile this example into C++.
      }
    EOF

-If you installed Verilator from sources, or a tarball, but not as part of
-your operating system (as an RPM), first you need to point to the kit:
+See the README in the source kit for various ways to install or point to
+Verilator binaries.  In brief, if you are running Verilator that came from
+your operating system (as an RPM), or did a "make install" to place
+Verilator into your default path, you do not need anything special in your
+environment, and should not have VERILATOR_ROOT set.  However, if you
+installed Verilator from sources and want to run Verilator out of where you
+compiled Verilator, you need to point to the kit:

+    # See above; don't do this if using an OS-distributed Verilator
    export VERILATOR_ROOT=/path/to/where/verilator/was/installed
    export PATH=$VERILATOR_ROOT/bin:$PATH

@@ -1289,8 +1384,7 @@ section below for descriptions of some of the files that were created.

 We then can compile it

-    cd obj_dir
-    make -j -f Vour.mk Vour
+    make -j -C obj_dir -f Vour.mk Vour

 (Verilator included a default compile rule and link rule, since we used
 --exe and passed a .cpp file on the Verilator command line.  You can also
@@ -1298,7 +1392,6 @@ write your own compile rules, as we'll show in the SYSTEMC section.)

 And now we run it

-    cd ..
    obj_dir/Vour

 And we get as output
@@ -1307,8 +1400,9 @@ And we get as output
    - our.v:2: Verilog $finish

 Really, you're better off writing a Makefile to do all this for you.  Then,
-when your source changes it will automatically run all of these steps.  See
-the test_c directory in the distribution for an example.
+when your source changes it will automatically run all of these steps; to
+aid this Verilator can create a makefile dependency file.  See the test_c
+directory in the distribution for an example.


 =head1 EXAMPLE SYSTEMC EXECUTION
@@ -1329,20 +1423,26 @@ This is an example similar to the above, but using SystemC.
    cat <<EOF >sc_main.cpp
      #include "Vour.h"
      int sc_main(int argc, char **argv) {
-	  Verilated::commandArgs(argc, argv);
+          Verilated::commandArgs(argc, argv);
          sc_clock clk ("clk",10, 0.5, 3, true);
          Vour* top;
          top = new Vour("top");   // SP_CELL (top, Vour);
          top->clk(clk);           // SP_PIN  (top, clk, clk);
          while (!Verilated::gotFinish()) { sc_start(1, SC_NS); }
-          delete top; 
+          delete top;
          exit(0);
      }
    EOF

-If you installed Verilator from sources, or a tarball, but not as part of
-your operating system (as an RPM), first you need to point to the kit:
+See the README in the source kit for various ways to install or point to
+Verilator binaries.  In brief, if you are running Verilator that came from
+your operating system (as an RPM), or did a "make install" to place
+Verilator into your default path, you do not need anything special in your
+environment, and should not have VERILATOR_ROOT set.  However, if you
+installed Verilator from sources and want to run Verilator out of where you
+compiled Verilator, you need to point to the kit:

+    # See above; don't do this if using an OS-distributed Verilator
    export VERILATOR_ROOT=/path/to/where/verilator/was/installed
    export PATH=$VERILATOR_ROOT/bin:$PATH

@@ -1352,6 +1452,7 @@ Now we run Verilator on our little example.

 We then can compile it

+    cd obj_dir
    make -j -f Vour.mk Vour__ALL.a
    make -j -f Vour.mk ../sc_main.o verilated.o

@@ -1457,42 +1558,42 @@ All output files are placed in the output directory name specified with the

 Verilator creates the following files in the output directory:

-    {prefix}.mk				// Make include file for compiling
-    {prefix}_classes.mk			// Make include file with class names
+    {prefix}.mk                         // Make include file for compiling
+    {prefix}_classes.mk                 // Make include file with class names

 For -cc and -sc mode, it also creates:

-    {prefix}.cpp			// Top level C++ file
-    {prefix}.h				// Top level header
-    {prefix}{each_verilog_module}.cpp	// Lower level internal C++ files
-    {prefix}{each_verilog_module}.h	// Lower level internal header files
+    {prefix}.cpp                        // Top level C++ file
+    {prefix}.h                          // Top level header
+    {prefix}{each_verilog_module}.cpp   // Lower level internal C++ files
+    {prefix}{each_verilog_module}.h     // Lower level internal header files

 In certain optimization modes, it also creates:

-    {prefix}__Dpi.h			// DPI import and export declarations
-    {prefix}__Inlines.h			// Inline support functions
-    {prefix}__Slow.cpp			// Constructors and infrequent routines
-    {prefix}__Syms.cpp			// Global symbol table C++
-    {prefix}__Syms.h			// Global symbol table header
-    {prefix}__Trace.cpp			// Wave file generation code (--trace)
-    {prefix}__cdc.txt			// Clock Domain Crossing checks (--cdc)
-    {prefix}__stats.txt			// Statistics (--stats)
+    {prefix}__Dpi.h                     // DPI import and export declarations
+    {prefix}__Inlines.h                 // Inline support functions
+    {prefix}__Slow.cpp                  // Constructors and infrequent routines
+    {prefix}__Syms.cpp                  // Global symbol table C++
+    {prefix}__Syms.h                    // Global symbol table header
+    {prefix}__Trace.cpp                 // Wave file generation code (--trace)
+    {prefix}__cdc.txt                   // Clock Domain Crossing checks (--cdc)
+    {prefix}__stats.txt                 // Statistics (--stats)

 It also creates internal files that can be mostly ignored:

-    {each_verilog_module}.vpp		// Post-processed verilog (--debug)
-    {prefix}.flags_vbin			// Verilator dependencies
-    {prefix}.flags_vpp			// Pre-processor dependencies
-    {prefix}__verFiles.dat		// Timestamps for skip-identical
-    {prefix}{misc}.d			// Make dependencies (-MMD)
-    {prefix}{misc}.dot			// Debugging graph files (--debug)
-    {prefix}{misc}.tree			// Debugging files (--debug)
+    {each_verilog_module}.vpp           // Post-processed verilog (--debug)
+    {prefix}.flags_vbin                 // Verilator dependencies
+    {prefix}.flags_vpp                  // Pre-processor dependencies
+    {prefix}__verFiles.dat              // Timestamps for skip-identical
+    {prefix}{misc}.d                    // Make dependencies (-MMD)
+    {prefix}{misc}.dot                  // Debugging graph files (--debug)
+    {prefix}{misc}.tree                 // Debugging files (--debug)

 After running Make, the C++ compiler should produce the following:

-    {prefix}				// Final executable (w/--exe argument)
-    {prefix}__ALL.a			// Library of all Verilated objects
-    {prefix}{misc}.o			// Intermediate objects
+    {prefix}                            // Final executable (w/--exe argument)
+    {prefix}__ALL.a                     // Library of all Verilated objects
+    {prefix}{misc}.o                    // Intermediate objects


 =head1 ENVIRONMENT
@@ -1587,46 +1688,47 @@ simulation executable.
 The user must write the top level of the simulation.  Here's a simple
 example:

-	#include <verilated.h>		// Defines common routines
-	#include "Vtop.h"		// From Verilating "top.v"
+        #include <verilated.h>          // Defines common routines
+        #include <iostream>             // Need std::cout
+        #include "Vtop.h"               // From Verilating "top.v"

-	Vtop *top;			// Instantiation of module
+        Vtop *top;                      // Instantiation of module

-	vluint64_t main_time = 0;	// Current simulation time
-	// This is a 64-bit integer to reduce wrap over issues and
-	// allow modulus.  You can also use a double, if you wish.
+        vluint64_t main_time = 0;       // Current simulation time
+        // This is a 64-bit integer to reduce wrap over issues and
+        // allow modulus.  You can also use a double, if you wish.

-	double sc_time_stamp () {	// Called by $time in Verilog
-	    return main_time;		// converts to double, to match
-					// what SystemC does    
-	}
+        double sc_time_stamp () {       // Called by $time in Verilog
+            return main_time;           // converts to double, to match
+                                        // what SystemC does
+        }

-	int main(int argc, char** argv) {
-	    Verilated::commandArgs(argc, argv);   // Remember args
+        int main(int argc, char** argv) {
+            Verilated::commandArgs(argc, argv);   // Remember args

-	    top = new Vtop;		// Create instance
+            top = new Vtop;             // Create instance

-	    top->reset_l = 0;		// Set some inputs
+            top->reset_l = 0;           // Set some inputs

-	    while (!Verilated::gotFinish()) {
-		if (main_time > 10) {
-		    top->reset_l = 1;	// Deassert reset
-		}
-		if ((main_time % 10) == 1) {
-		    top->clk = 1;	// Toggle clock
-		}
-		if ((main_time % 10) == 6) {
-		    top->clk = 0;
-		}
-		top->eval();		// Evaluate model
-		cout << top->out << endl;	// Read a output
-		main_time++;		// Time passes...
-	    }
+            while (!Verilated::gotFinish()) {
+                if (main_time > 10) {
+                    top->reset_l = 1;   // Deassert reset
+                }
+                if ((main_time % 10) == 1) {
+                    top->clk = 1;       // Toggle clock
+                }
+                if ((main_time % 10) == 6) {
+                    top->clk = 0;
+                }
+                top->eval();            // Evaluate model
+                cout << top->out << endl;       // Read a output
+                main_time++;            // Time passes...
+            }

-	    top->final();		// Done simulating
-	    //	  // (Though this example doesn't get here)
-	    delete top;
-	}
+            top->final();               // Done simulating
+            //    // (Though this example doesn't get here)
+            delete top;
+        }

 Note signals are read and written as member variables of the lower module.
 You call the eval() method to evaluate the model.  When the simulation is
@@ -1802,6 +1904,8 @@ Verilator supports a very limited subset of the VPI.  This subset allows
 inspection, examination, value change callbacks, and depositing of values
 to public signals only.

+VPI is enabled with the verilator --vpi switch.
+
 To access signals via the VPI, Verilator must be told exactly which signals
 are to be accessed.  This is done using the Verilator public pragmas
 documented below.
@@ -1835,17 +1939,28 @@ changed on the specified clock edge.
 There are many online tutorials and books on the VPI, but an example that
 accesses the above would be:

-void read_and_check() {
-    vpiHandle vh1 = vpi_handle_by_name((PLI_BYTE8*)"t.readme", NULL);
-    if (!vh1) { error... }
-    const char* name = vpi_get_str(vpiName, vh1);
-    printf("Module name: %s\n");  // Prints "readme"
+    void read_and_check() {
+        vpiHandle vh1 = vpi_handle_by_name((PLI_BYTE8*)"t.readme", NULL);
+        if (!vh1) { error... }
+        const char* name = vpi_get_str(vpiName, vh1);
+        printf("Module name: %s\n");  // Prints "readme"

-    s_vpi_value v;
-    v.format = vpiIntVal;
-    vpi_get_value(vh1, &v);
-    printf("Value of v: %d\n", v.value.integer);  // Prints "readme"
-}
+        s_vpi_value v;
+        v.format = vpiIntVal;
+        vpi_get_value(vh1, &v);
+        printf("Value of v: %d\n", v.value.integer);  // Prints "readme"
+    }
+
+For signal callbacks to work the main loop of the program must call
+VerilatedVpi::callValueCbs().
+
+    #include "verilated_vpi.h"  // Required to get definitions
+    ...
+    while (time passes) {
+        ...
+        topp->eval();
+        VerilatedVpi::callValueCbs();
+    }


 =head1 CROSS COMPILATION
@@ -1888,10 +2003,10 @@ underneath NC:

   cd obj_dir
   ncsc_run \
-	sc_main.cpp \
-	Vour__ALLcls.cpp \
-	Vour__ALLsup.cpp \
-	verilated.cpp
+        sc_main.cpp \
+        Vour__ALLcls.cpp \
+        Vour__ALLsup.cpp \
+        verilated.cpp

 For larger designs you'll want to automate this using makefiles, which pull
 the names of the .cpp files to compile in from the make variables generated
@@ -1923,30 +2038,41 @@ The grammar of configuration commands is as follows:
 Take remaining text up the the next `verilog mode switch and treat it as
 Verilator configuration commands.

+=item coverage_on  [-file "<filename>" [-lines <line> [ - <line> ]]]
+
 =item coverage_off [-file "<filename>" [-lines <line> [ - <line> ]]]

-Disable coverage for the specified filename (or wildcard with '*' or '?',
-or all files if omitted) and range of line numbers (or all lines if
+Enable/disable coverage for the specified filename (or wildcard with '*' or
+'?', or all files if omitted) and range of line numbers (or all lines if
 omitted).  Often used to ignore an entire module for coverage analysis
 purposes.

+=item lint_on  [-msg <message>] [-file "<filename>" [-lines <line> [ - <line>]]]
+
 =item lint_off [-msg <message>] [-file "<filename>" [-lines <line> [ - <line>]]]

-Disables the specified lint warning, in the specified filename (or wildcard
-with '*' or '?', or all files if omitted) and range of line numbers (or all
-lines if omitted).
+Enable/disables the specified lint warning, in the specified filename (or
+wildcard with '*' or '?', or all files if omitted) and range of line
+numbers (or all lines if omitted).

-Using '*' will override any lint_on directives in the source, i.e. the
-warning will still not be printed.
+With lint_off using '*' will override any lint_on directives in the source,
+i.e. the warning will still not be printed.

-If the -msg is omitted, all lint warnings are disabled.  This will override
-all later lint warning enables for the specified region.
+If the -msg is omitted, all lint warnings (see list in -Wno-lint) are
+enabled/disabled.  This will override all later lint warning enables for
+the specified region.
+
+=item tracing_on  [-file "<filename>" [-lines <line> [ - <line> ]]]

 =item tracing_off [-file "<filename>" [-lines <line> [ - <line> ]]]

-Disable waveform tracing for all future signals declared in the specified
-filename (or wildcard with '*' or '?', or all files if omitted) and range
-of line numbers (or all lines if omitted).
+Enable/disable waveform tracing for all future signals declared in the
+specified filename (or wildcard with '*' or '?', or all files if omitted)
+and range of line numbers (or all lines if omitted).
+
+For tracing_off, cells below any module in the files/ranges specified will
+also not be traced.
+

 =back

@@ -2075,45 +2201,52 @@ per the C standard (it's unspecified in Verilog).

 =item `coverage_block_off

-Specifies the entire begin/end block should be ignored for coverage analysis.
+Specifies the entire begin/end block should be ignored for coverage
+analysis.  Must be inside a basic block, e.g. within a begin/end pair.
 Same as /* verilator coverage_block_off */.

 =item `systemc_header

 Take remaining text up to the next `verilog or `systemc_... mode switch and
-place it verbatim into the output .h file's header.  Despite the name of this
-macro, this also works in pure C++ code.
+place it verbatim into the output .h file's header.  Must be placed as a
+module item, e.g. directly inside a module/endmodule pair. Despite the name
+of this macro, this also works in pure C++ code.

 =item `systemc_ctor

 Take remaining text up to the next `verilog or `systemc_... mode switch and
-place it verbatim into the C++ class constructor.  Despite the name of this
-macro, this also works in pure C++ code.
+place it verbatim into the C++ class constructor.  Must be placed as a
+module item, e.g. directly inside a module/endmodule pair. Despite the name
+of this macro, this also works in pure C++ code.

 =item `systemc_dtor

 Take remaining text up to the next `verilog or `systemc_... mode switch and
-place it verbatim into the C++ class destructor.  Despite the name of this
-macro, this also works in pure C++ code.
+place it verbatim into the C++ class destructor.  Must be placed as a
+module item, e.g. directly inside a module/endmodule pair. Despite the name
+of this macro, this also works in pure C++ code.

 =item `systemc_interface

 Take remaining text up to the next `verilog or `systemc_... mode switch and
-place it verbatim into the C++ class interface.  Despite the name of this
-macro, this also works in pure C++ code.
+place it verbatim into the C++ class interface.  Must be placed as a module
+item, e.g. directly inside a module/endmodule pair. Despite the name of
+this macro, this also works in pure C++ code.

 =item `systemc_imp_header

 Take remaining text up to the next `verilog or `systemc_... mode switch and
 place it verbatim into the header of all files for this C++ class
-implementation.  Despite the name of this macro, this also works in pure
-C++ code.
+implementation.  Must be placed as a module item, e.g. directly inside a
+module/endmodule pair. Despite the name of this macro, this also works in
+pure C++ code.

 =item `systemc_implementation

 Take remaining text up to the next `verilog or `systemc_... mode switch and
-place it verbatim into a single file of the C++ class implementation.
-Despite the name of this macro, this also works in pure C++ code.
+place it verbatim into a single file of the C++ class implementation.  Must
+be placed as a module item, e.g. directly inside a module/endmodule
+pair. Despite the name of this macro, this also works in pure C++ code.

 If you will be reading or writing any Verilog variables in the C++
 functions, the Verilog signals must be declared with /*verilator public*/.
@@ -2268,6 +2401,14 @@ reduce the size of the final executable when a task is used a very large
 number of times.  For this flag to work, the task and tasks below it must
 be pure; they cannot reference any variables outside the task itself.

+=item /*verilator public*/ (parameter)
+
+Used after a parameter declaration to indicate the emitted C code should
+have the parameter values visible. Due to C++ language restrictions, this
+may only be used on 64-bit or narrower integral enumerations.
+
+    parameter [2:0] PARAM /*verilator public*/ = 2'b0;
+
 =item /*verilator public*/ (typedef enum)

 Used after an enum typedef declaration to indicate the emitted C code
@@ -2391,16 +2532,24 @@ such as $stop, $finish and $display.  That is, you cannot use hierarchical
 references, events or similar features of the Verilog language.  It also
 simulates as Synopsys's Design Compiler would; namely a block of the form:

-	always @ (x)   y = x & z;
+        always @ (x)   y = x & z;

 This will recompute y when there is even a potential for change in x or a
 change in z, that is when the flops computing x or z evaluate (which is
 what Design Compiler will synthesize.)  A compliant simulator would only
-calculate y if x changes.  Use verilog-mode's /*AS*/ or Verilog 2001's
+calculate y if x changes.  Use Verilog-Mode's /*AS*/ or Verilog 2001's
 always @* to reduce missing activity items.  Avoid putting $displays in
 combo blocks, as they may print multiple times when not desired, even on
 compliant simulators as event ordering is not specified.

+=head2 Signal Naming
+
+To avoid conflicts with C symbol naming, any character in a signal name
+that is not alphanumeric nor a single underscore will be replaced by __0hh
+where hh is the hex code of the character. To avoid conflicts with
+Verilator's internal symbols, any double underscore are replaced with
+___05F (5F is the hex code of an underscore.)
+
 =head2 Bind

 Verilator only supports "bind" to a target module name, not an instance
@@ -2479,7 +2628,7 @@ variables are initialized to a random value.
 Event driven simulators will generally trigger an edge on a transition from X
 to 1 (C<posedge>) or X to 0 (C<negedge>). However, by default, since clocks
 are initialized to zero, Verilator will not trigger an initial negedge. Some
-code (particulary for reset) may rely on X->0 triggering an edge. Verilator
+code (particularly for reset) may rely on X->0 triggering an edge. Verilator
 provides a switch (see --x-initial-edge) to enable this behavior. Comparing
 runs with and without this switch will find such problems.

@@ -2532,7 +2681,7 @@ clock_enable*/ attribute.
 =head2 Ranges must be big-bit-endian

 Bit ranges must be numbered with the MSB being numbered greater or the same
-as the LSB.  Little-bit-endian busses [0:15] are not supported as they
+as the LSB.  Little-bit-endian buses [0:15] are not supported as they
 aren't easily made compatible with C++.

 =head2 Gate Primitives
@@ -2731,13 +2880,17 @@ when displaying all times, model wide.

 =head1 ERRORS AND WARNINGS

-Warnings may be disabled in two ways.  First, when the warning is
+Warnings may be disabled in three ways.  First, when the warning is
 printed it will include a warning code.  Simply surround the offending
 line with a warn_off/warn_on pair:

-	// verilator lint_off UNSIGNED
-	if (`DEF_THAT_IS_EQ_ZERO <= 3) $stop;
-	// verilator lint_on UNSIGNED
+        // verilator lint_off UNSIGNED
+        if (`DEF_THAT_IS_EQ_ZERO <= 3) $stop;
+        // verilator lint_on UNSIGNED
+
+Second, warnings may be disabled using a configuration file with a lint_off
+command.  This is useful when a script is suppressing warnings and the
+Verilog source should not be changed.

 Warnings may also be globally disabled by invoking Verilator with the
 C<-Wno-I<warning>> switch.  This should be avoided, as it removes all
@@ -2801,13 +2954,12 @@ Simply use a different register for the flop:
      always @* foo[0] = foo_flopped[0];
      always @* foo[1] = ...

-This is good coding practice anyways.
-
 It is also possible to disable this error when one of the assignments is
 inside a public task.

-Ignoring this warning may make Verilator simulations differ from other
-simulators.
+This is not illegal in SystemVerilog, but a violation of good coding
+practice. Verilator reports this as an error, because ignoring this warning
+may make Verilator simulations differ from other simulators.

 =item BLKSEQ

@@ -2831,10 +2983,10 @@ were used, the simulator would have to copy large arrays every cycle.  (In
 smaller loops, loop unrolling allows the delayed assignment to work, though
 it's a bit slower than a non-delayed assignment.)  Here's an example

-	always @ (posedge clk)
+        always @ (posedge clk)
            if (~reset_l) begin
                for (i=0; i<`ARRAY_SIZE; i++) begin
-		    array[i] = 0;	 // Non-delayed for verilator
+                    array[i] = 0;        // Non-delayed for verilator
                end

 This message is only seen on large or complicated loops because Verilator
@@ -3292,9 +3444,9 @@ A recommended style for unused nets is to put at the bottom of a file code
 similar to the following:

    wire _unused_ok = &{1'b0,
-    			sig_not_used_a,
-    			sig_not_used_yet_b,  // To be fixed
-    			1'b0};
+                        sig_not_used_a,
+                        sig_not_used_yet_b,  // To be fixed
+                        1'b0};

 The reduction AND and constant zeros mean the net will always be zero, so
 won't use simulation time.  The redundant leading and trailing zeros avoid
@@ -3305,6 +3457,10 @@ with "unused" in the name, or put the appropriate lint_off around the wire.
 Having unused signals in one place makes it easy to find what is unused,
 and reduces the number of lint_off pragmas, reducing bugs.

+=item USERINFO, USERWARN, USERERROR, USERFATAL
+
+A SystemVerilog elaboration-time assertion print was executed.
+
 =item VARHIDDEN

 Warns that a task, function, or begin/end block is declaring a variable by
@@ -3327,11 +3483,11 @@ unwidthed. Verilator considers zero to be any width needed.

 Concatenate leading zeros when doing arithmetic.  In the statement

-	wire [5:0] plus_one = from[5:0] + 6'd1 + carry[0];
+        wire [5:0] plus_one = from[5:0] + 6'd1 + carry[0];

 The best fix, which clarifies intent and will also make all tools happy is:

-	wire [5:0] plus_one = from[5:0] + 6'd1 + {5'd0,carry[0]};
+        wire [5:0] plus_one = from[5:0] + 6'd1 + {5'd0,carry[0]};

 Ignoring this warning will only suppress the lint check, it will simulate
 correctly.
@@ -3529,7 +3685,7 @@ trace file if you want all data to land in the same output file.
        tfp->open ("obj_dir/t_trace_ena_cc/simx.vcd");
        ...
        sc_start(1);
-	...
+        ...
        tfp->close();
    }

@@ -3563,7 +3719,10 @@ First, run verilator with the --coverage option.  If you're using your own
 makefile, compile the model with the GCC flag -DVM_COVERAGE (if using
 Verilator's, it will do this for you.)

-Run your tests in different directories.  Each test will create a
+At the end of your test, call VerilatedCov::write passing the name of the
+coverage data file (typically "logs/coverage.dat").
+
+Run each of your tests in different directories.  Each test will create a
 logs/coverage.pl file.

 After running all of your tests, verilator_coverage is executed.
@@ -3873,7 +4032,7 @@ Thanks to them, and all those we've missed including above.

 The latest version is available from L<http://www.veripool.org/>.

-Copyright 2003-2015 by Wilson Snyder.  Verilator is free software; you can
+Copyright 2003-2017 by Wilson Snyder.  Verilator is free software; you can
 redistribute it and/or modify the Verilator internals under the terms of
 either the GNU Lesser General Public License Version 3 or the Perl Artistic
 License Version 2.0.
@@ -3,7 +3,7 @@ eval 'exec perl -wS $0 ${1+"$@"}'
  if 0;
 ######################################################################
 #
-# Copyright 2003-2015 by Wilson Snyder. This program is free software; you
+# Copyright 2003-2017 by Wilson Snyder. This program is free software; you
 # can redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
@@ -271,7 +271,7 @@ Specifies a module search directory.

 The latest version is available from L<http://www.veripool.org/>.

-Copyright 2003-2015 by Wilson Snyder.  Verilator is free software; you can
+Copyright 2003-2017 by Wilson Snyder.  Verilator is free software; you can
 redistribute it and/or modify the Verilator internals under the terms of
 either the GNU Lesser General Public License Version 3 or the Perl Artistic
 License Version 2.0.
@@ -235,7 +235,7 @@ Do not show differences in line numbering.

 The latest version is available from L<http://www.veripool.org/verilator>.

-Copyright 2005-2015 by Wilson Snyder.  This package is free software; you can
+Copyright 2005-2017 by Wilson Snyder.  This package is free software; you can
 redistribute it and/or modify it under the terms of either the GNU Lesser
 General Public License Version 3 or the Perl Artistic License Version 2.0.

@@ -3,7 +3,7 @@ eval 'exec perl -wS $0 ${1+"$@"}'
  if 0;
 # DESCRIPTION: Print include statements for each ARGV
 #
-# Copyright 2003-2015 by Wilson Snyder. This package is free software; you can
+# Copyright 2003-2017 by Wilson Snyder. This package is free software; you can
 # redistribute it and/or modify it under the terms of either the GNU Lesser
 # General Public License Version 3 or the Perl Artistic License Version 2.0.
 ######################################################################
@@ -222,7 +222,7 @@ Displays this message and program version and exits.

 The latest version is available from L<http://www.veripool.org/>.

-Copyright 2007-2015 by Wilson Snyder.  Verilator is free software; you can
+Copyright 2007-2017 by Wilson Snyder.  Verilator is free software; you can
 redistribute it and/or modify it under the terms of either the GNU Lesser
 General Public License Version 3 or the Perl Artistic License Version 2.0.

@@ -1,19 +1,21 @@
 # DESCRIPTION: Process this file with autoconf to produce a configure script.
 #
-# Copyright 2003-2015 by Wilson Snyder. Verilator is free software; you can
+# Copyright 2003-2017 by Wilson Snyder. Verilator is free software; you can
 # redistribute it and/or modify it under the terms of either the GNU Lesser
 # General Public License Version 3 or the Perl Artistic License Version 2.0.

 #AC_INIT([Verilator],[#.### YYYY-MM-DD])
 #AC_INIT([Verilator],[#.### devel])
-AC_INIT([Verilator],[3.874 2015-06-06])
+AC_INIT([Verilator],[3.902 2017-04-02])
+# When releasing, also update header of Changes file
+
 AC_CONFIG_HEADER(src/config_build.h)
 AC_CONFIG_FILES(Makefile src/Makefile src/Makefile_obj include/verilated.mk include/verilated_config.h verilator.pc)

 AC_MSG_RESULT([configuring for $PACKAGE_STRING])

 # Special Substitutions - CFG_WITH_DEFENV
-AC_MSG_CHECKING(whether to disable hardcoded paths)
+AC_MSG_CHECKING(whether to use hardcoded paths)
 AC_ARG_ENABLE([defenv],
              [AS_HELP_STRING([--disable-defenv],
                              [disable using some hardcoded data paths extracted from some default environment variables (the default is to use hardcoded paths)])],
@@ -118,6 +120,18 @@ AC_DEFUN([_MY_CXX_CHECK_OPT],
 	    fi
 	  fi],
 	 [_my_result=no])
+    # GCC is annoying, trying to be helpful, it postpones unknown -Wno-
+    # options if there's no error We want to see them regardless, so try
+    # forcing an error and see if we get a gcc warning
+    AC_COMPILE_IFELSE(
+         [AC_LANG_PROGRAM([[an_error "intentional-error-for-test.h"
+	                  ]],[])],
+         [], # Ignore ok exit
+         [if test -s conftest.err; then
+            if grep -e "$2" conftest.err >/dev/null; then
+              _my_result=no
+            fi
+          fi])
    AC_MSG_RESULT($_my_result)
    if test "$_my_result" = "yes" ; then
       $1="$$1 $2"
@@ -128,7 +142,9 @@ AC_DEFUN([_MY_CXX_CHECK_OPT],
 # Flags for compiling Verilator internals including parser
 _MY_CXX_CHECK_OPT(CFG_CXXFLAGS_SRC,-Wno-unused-parameter)
 _MY_CXX_CHECK_OPT(CFG_CXXFLAGS_SRC,-Wno-char-subscripts)
+_MY_CXX_CHECK_OPT(CFG_CXXFLAGS_SRC,-Wno-undefined-bool-conversion)
 _MY_CXX_CHECK_OPT(CFG_CXXFLAGS_SRC,-Qunused-arguments)
+_MY_CXX_CHECK_OPT(CFG_CXXFLAGS_SRC,-fno-delete-null-pointer-checks)
 AC_SUBST(CFG_CXXFLAGS_SRC)

 # Flags for compiling Verilator parser
@@ -1,7 +1,7 @@
 // -*- mode: C++; c-file-style: "cc-mode" -*-
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder. This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder. This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License.
 // Version 2.0.
@@ -374,7 +374,7 @@ void _vl_vsformat(string& output, const char* formatp, va_list ap) {
 		} else {
 		    lwp = va_arg(ap,WDataInP);
 		    ld = lwp[0];
-		    if (fmt == 'u' || fmt == 'd') fmt = 'x';  // Not supported, but show something
+		    if (fmt == 'd' || fmt == '#') fmt = 'x';  // Not supported, but show something
 		}
 		int lsb=lbits-1;
 		if (widthSet && width==0) while (lsb && !VL_BITISSET_W(lwp,lsb)) lsb--;
@@ -404,7 +404,7 @@ void _vl_vsformat(string& output, const char* formatp, va_list ap) {
 		    output += tmp;
 		    break;
 		}
-		case 'u': { // Unsigned decimal
+		case '#': { // Unsigned decimal
 		    int digits=sprintf(tmp,"%" VL_PRI64 "u",ld);
 		    int needmore = width-digits;
 		    if (needmore>0) {
@@ -438,6 +438,7 @@ void _vl_vsformat(string& output, const char* formatp, va_list ap) {
 			output += ((lwp[VL_BITWORD_I(lsb)]>>VL_BITBIT_I(lsb)) & 1) + '0';
 		    }
 		    break;
+		    break;
 		case 'o':
 		    for (; lsb>=0; lsb--) {
 			lsb = (lsb / 3) * 3; // Next digit
@@ -450,6 +451,28 @@ void _vl_vsformat(string& output, const char* formatp, va_list ap) {
 				   + ((VL_BITISSETLIMIT_W(lwp, lbits, lsb+2)) ? 4 : 0));
 		    }
 		    break;
+		case 'u':  // Packed 2-state
+		    output.reserve(output.size() + 4*VL_WORDS_I(lbits));
+		    for (int i=0; i<VL_WORDS_I(lbits); i++) {
+			output += (char)((lwp[i] >> 0) & 0xff);
+			output += (char)((lwp[i] >> 8) & 0xff);
+			output += (char)((lwp[i] >> 16) & 0xff);
+			output += (char)((lwp[i] >> 24) & 0xff);
+		    }
+		case 'z':  // Packed 4-state
+		    output.reserve(output.size() + 8*VL_WORDS_I(lbits));
+		    for (int i=0; i<VL_WORDS_I(lbits); i++) {
+			output += (char)((lwp[i] >> 0) & 0xff);
+			output += (char)((lwp[i] >> 8) & 0xff);
+			output += (char)((lwp[i] >> 16) & 0xff);
+			output += (char)((lwp[i] >> 24) & 0xff);
+			output += "\0\0\0\0"; // No tristate
+		    }
+		case 'v': // Strength; assume always strong
+		    for (lsb=lbits-1; lsb>=0; lsb--) {
+			if ((lwp[VL_BITWORD_I(lsb)]>>VL_BITBIT_I(lsb)) & 1) output += "St1 ";
+			else output += "St0 ";
+		    }
 		case 'x':
 		    for (; lsb>=0; lsb--) {
 			lsb = (lsb / 4) * 4; // Next digit
@@ -627,13 +650,14 @@ IData _vl_vsscanf(FILE* fp,  // If a fscanf
 		    _vl_vsss_skipspace(fp,floc,fromp,fstr);
 		    _vl_vsss_read(fp,floc,fromp,fstr, tmp, "+-.0123456789eE");
 		    if (!tmp[0]) goto done;
+		    // cppcheck-suppress unusedStructMember  // It's used
 		    union { double r; vlsint64_t ld; } u;
 		    u.r = strtod(tmp, NULL);
 		    VL_SET_WQ(owp,u.ld);
 		    break;
 		}
 		case 't': // FALLTHRU  // Time
-		case 'u': { // Unsigned decimal
+		case '#': { // Unsigned decimal
 		    _vl_vsss_skipspace(fp,floc,fromp,fstr);
 		    _vl_vsss_read(fp,floc,fromp,fstr, tmp, "0123456789+-xXzZ?_");
 		    if (!tmp[0]) goto done;
@@ -708,8 +732,8 @@ void _VL_VINT_TO_STRING(int obits, char* destoutp, WDataInP sourcep) {
 	    start = false;	// Drop leading 0s
 	}
    }
-    *destp++ = '\0'; // Terminate
-    while (isspace(*(destp-1)) && destp>destoutp) *--destp = '\0';  // Drop trailing spaces
+    *destp = '\0'; // Terminate
+    if (!start) while (isspace(*(destp-1)) && destp>destoutp) *--destp = '\0';  // Drop trailing spaces
 }

 void _VL_STRING_TO_VINT(int obits, void* destp, int srclen, const char* srcp) {
@@ -750,6 +774,11 @@ IData VL_FGETS_IXI(int obits, void* destp, IData fpi) {
    return got;
 }

+IData VL_FOPEN_NI(const string& filename, IData mode) {
+    char modez[5];
+    _VL_VINT_TO_STRING(VL_WORDSIZE, modez, &mode);
+    return VL_FOPEN_S(filename.c_str(), modez);
+}
 IData VL_FOPEN_QI(QData filename, IData mode) {
    IData fnw[2];  VL_SET_WQ(fnw, filename);
    return VL_FOPEN_WI(2, fnw, mode);
@@ -927,11 +956,18 @@ void VL_READMEM_W(bool hex, int width, int depth, int array_lsb, int fnwords,
 		  WDataInP ofilenamep, void* memp, IData start, IData end) {
    char ofilenamez[VL_TO_STRING_MAX_WORDS*VL_WORDSIZE+1];
    _VL_VINT_TO_STRING(fnwords*VL_WORDSIZE, ofilenamez, ofilenamep);
-    FILE* fp = fopen(ofilenamez, "r");
+    string ofilenames(ofilenamez);
+    return VL_READMEM_N(hex,width,depth,array_lsb,fnwords,ofilenames,memp,start,end);
+}
+
+void VL_READMEM_N(bool hex, int width, int depth, int array_lsb, int fnwords,
+		  const string& ofilenamep, void* memp, IData start, IData end) {
+    if (fnwords) {}
+    FILE* fp = fopen(ofilenamep.c_str(), "r");
    if (VL_UNLIKELY(!fp)) {
-	// We don't report the Verilog source filename as it slow to have to pass it down
-	vl_fatal (ofilenamez, 0, "", "$readmem file not found");
-	return;
+        // We don't report the Verilog source filename as it slow to have to pass it down
+        vl_fatal (ofilenamep.c_str(), 0, "", "$readmem file not found");
+        return;
    }
    // Prep for reading
    IData addr = start;
@@ -946,81 +982,81 @@ void VL_READMEM_W(bool hex, int width, int depth, int array_lsb, int fnwords,
    // We process a character at a time, as then we don't need to deal
    // with changing buffer sizes dynamically, etc.
    while (1) {
-	int c = fgetc(fp);
-	if (VL_UNLIKELY(c==EOF)) break;
-	//printf("%d: Got '%c' Addr%x IN%d IgE%d IgC%d ninc%d\n", linenum, c, addr, innum, ignore_to_eol, ignore_to_cmt, needinc);
-	if (c=='\n') { linenum++; ignore_to_eol=false; if (innum) reading_addr=false; innum=false; }
-	else if (c=='\t' || c==' ' || c=='\r' || c=='\f') { if (innum) reading_addr=false; innum=false; }
-	// Skip // comments and detect /* comments
-	else if (ignore_to_cmt && lastc=='*' && c=='/') {
-	    ignore_to_cmt = false; if (innum) reading_addr=false; innum=false;
-	} else if (!ignore_to_eol && !ignore_to_cmt) {
-	    if (lastc=='/' && c=='*') { ignore_to_cmt = true; }
-	    else if (lastc=='/' && c=='/') { ignore_to_eol = true; }
-	    else if (c=='/') {}  // Part of /* or //
-	    else if (c=='_') {}
-	    else if (c=='@') { reading_addr = true; innum=false; needinc=false; }
-	    // Check for hex or binary digits as file format requests
-	    else if (isxdigit(c)) {
-		c = tolower(c);
-		int value = (c >= 'a' ? (c-'a'+10) : (c-'0'));
-		if (!innum) {  // Prep for next number
-		    if (needinc) { addr++; needinc=false; }
-		}
-		if (reading_addr) {
-		    // Decode @ addresses
-		    if (!innum) addr=0;
-		    addr = (addr<<4) + value;
-		} else {
-		    needinc = true;
-		    //printf(" Value width=%d  @%x = %c\n", width, addr, c);
-		    if (VL_UNLIKELY(addr >= (IData)(depth+array_lsb) || addr < (IData)(array_lsb))) {
-			vl_fatal (ofilenamez, linenum, "", "$readmem file address beyond bounds of array");
-		    } else {
-			int entry = addr - array_lsb;
-			QData shift = hex ? VL_ULL(4) : VL_ULL(1);
-			// Shift value in
-			if (width<=8) {
-			    CData* datap = &((CData*)(memp))[entry];
-			    if (!innum) { *datap = 0; }
-			    *datap = ((*datap << shift) + value) & VL_MASK_I(width);
-			} else if (width<=16) {
-			    SData* datap = &((SData*)(memp))[entry];
-			    if (!innum) { *datap = 0; }
-			    *datap = ((*datap << shift) + value) & VL_MASK_I(width);
-			} else if (width<=VL_WORDSIZE) {
-			    IData* datap = &((IData*)(memp))[entry];
-			    if (!innum) { *datap = 0; }
-			    *datap = ((*datap << shift) + value) & VL_MASK_I(width);
-			} else if (width<=VL_QUADSIZE) {
-			    QData* datap = &((QData*)(memp))[entry];
-			    if (!innum) { *datap = 0; }
-			    *datap = ((*datap << (QData)(shift)) + (QData)(value)) & VL_MASK_Q(width);
-			} else {
-			    WDataOutP datap = &((WDataOutP)(memp))[ entry*VL_WORDS_I(width) ];
-			    if (!innum) { VL_ZERO_RESET_W(width, datap); }
-			    _VL_SHIFTL_INPLACE_W(width, datap, (IData)shift);
-			    datap[0] |= value;
-			}
-			if (VL_UNLIKELY(value>=(1<<shift))) {
-			    vl_fatal (ofilenamez, linenum, "", "$readmemb (binary) file contains hex characters");
-			}
-		    }
-		}
-		innum = true;
-	    }
-	    else {
-		vl_fatal (ofilenamez, linenum, "", "$readmem file syntax error");
-	    }
-	}
-	lastc = c;
+        int c = fgetc(fp);
+        if (VL_UNLIKELY(c==EOF)) break;
+        //printf("%d: Got '%c' Addr%x IN%d IgE%d IgC%d ninc%d\n", linenum, c, addr, innum, ignore_to_eol, ignore_to_cmt, needinc);
+        if (c=='\n') { linenum++; ignore_to_eol=false; if (innum) reading_addr=false; innum=false; }
+        else if (c=='\t' || c==' ' || c=='\r' || c=='\f') { if (innum) reading_addr=false; innum=false; }
+        // Skip // comments and detect /* comments
+        else if (ignore_to_cmt && lastc=='*' && c=='/') {
+            ignore_to_cmt = false; if (innum) reading_addr=false; innum=false;
+        } else if (!ignore_to_eol && !ignore_to_cmt) {
+            if (lastc=='/' && c=='*') { ignore_to_cmt = true; }
+            else if (lastc=='/' && c=='/') { ignore_to_eol = true; }
+            else if (c=='/') {}  // Part of /* or //
+            else if (c=='_') {}
+            else if (c=='@') { reading_addr = true; innum=false; needinc=false; }
+            // Check for hex or binary digits as file format requests
+            else if (isxdigit(c)) {
+                c = tolower(c);
+                int value = (c >= 'a' ? (c-'a'+10) : (c-'0'));
+                if (!innum) {  // Prep for next number
+                    if (needinc) { addr++; needinc=false; }
+                }
+                if (reading_addr) {
+                    // Decode @ addresses
+                    if (!innum) addr=0;
+                    addr = (addr<<4) + value;
+                } else {
+                    needinc = true;
+                    //printf(" Value width=%d  @%x = %c\n", width, addr, c);
+                    if (VL_UNLIKELY(addr >= (IData)(depth+array_lsb) || addr < (IData)(array_lsb))) {
+                        vl_fatal (ofilenamep.c_str(), linenum, "", "$readmem file address beyond bounds of array");
+                    } else {
+                        int entry = addr - array_lsb;
+                        QData shift = hex ? VL_ULL(4) : VL_ULL(1);
+                        // Shift value in
+                        if (width<=8) {
+                            CData* datap = &((CData*)(memp))[entry];
+                            if (!innum) { *datap = 0; }
+                            *datap = ((*datap << shift) + value) & VL_MASK_I(width);
+                        } else if (width<=16) {
+                            SData* datap = &((SData*)(memp))[entry];
+                            if (!innum) { *datap = 0; }
+                            *datap = ((*datap << shift) + value) & VL_MASK_I(width);
+                        } else if (width<=VL_WORDSIZE) {
+                            IData* datap = &((IData*)(memp))[entry];
+                            if (!innum) { *datap = 0; }
+                            *datap = ((*datap << shift) + value) & VL_MASK_I(width);
+                        } else if (width<=VL_QUADSIZE) {
+                            QData* datap = &((QData*)(memp))[entry];
+                            if (!innum) { *datap = 0; }
+                            *datap = ((*datap << (QData)(shift)) + (QData)(value)) & VL_MASK_Q(width);
+                        } else {
+                            WDataOutP datap = &((WDataOutP)(memp))[ entry*VL_WORDS_I(width) ];
+                            if (!innum) { VL_ZERO_RESET_W(width, datap); }
+                            _VL_SHIFTL_INPLACE_W(width, datap, (IData)shift);
+                            datap[0] |= value;
+                        }
+                        if (VL_UNLIKELY(value>=(1<<shift))) {
+                            vl_fatal (ofilenamep.c_str(), linenum, "", "$readmemb (binary) file contains hex characters");
+                        }
+                    }
+                }
+                innum = true;
+            }
+            else {
+                vl_fatal (ofilenamep.c_str(), linenum, "", "$readmem file syntax error");
+            }
+        }
+        lastc = c;
    }
    if (needinc) { addr++; needinc=false; }

    // Final checks
    fclose(fp);
    if (VL_UNLIKELY(end != VL_UL(0xffffffff) && addr != (end+1))) {
-	vl_fatal (ofilenamez, linenum, "", "$readmem file ended before specified ending-address");
+        vl_fatal (ofilenamep.c_str(), linenum, "", "$readmem file ended before specified ending-address");
    }
 }

@@ -1041,6 +1077,14 @@ IData VL_TESTPLUSARGS_I(const char* formatp) {
    else return 1;
 }

+IData VL_VALUEPLUSARGS_IN(int, const char* prefixp, char, string& ldr) {
+    const string& match = VerilatedImp::argPlusMatch(prefixp);
+    const char* dp = match.c_str() + 1 /*leading + */ + strlen(prefixp);
+    if (match == "") return 0;
+    ldr = string(dp);
+    return 1;
+}
+
 IData VL_VALUEPLUSARGS_IW(int rbits, const char* prefixp, char fmt, WDataOutP rwp) {
    const string& match = VerilatedImp::argPlusMatch(prefixp);
    const char* dp = match.c_str() + 1 /*leading + */ + strlen(prefixp);
@@ -1146,7 +1190,12 @@ void Verilated::commandArgs(int argc, const char** argv) {
 }

 const char* Verilated::commandArgsPlusMatch(const char* prefixp) {
-    return VerilatedImp::argPlusMatch(prefixp).c_str();
+    const string& match = VerilatedImp::argPlusMatch(prefixp);
+    static VL_THREAD char outstr[VL_VALUE_STRING_MAX_WIDTH];
+    if (match == "") return "";
+    strncpy(outstr, match.c_str(), VL_VALUE_STRING_MAX_WIDTH);
+    outstr[VL_VALUE_STRING_MAX_WIDTH-1] = '\0';
+    return outstr;
 }

 void Verilated::internalsDump() {
@@ -1165,6 +1214,10 @@ int Verilated::exportFuncNum(const char* namep) {
    return VerilatedImp::exportFind(namep);
 }

+const VerilatedScopeNameMap* Verilated::scopeNameMap() {
+    return VerilatedImp::scopeNameMap();
+}
+
 //===========================================================================
 // VerilatedModule:: Methods

@@ -1173,7 +1226,7 @@ VerilatedModule::VerilatedModule(const char* namep)
 }

 VerilatedModule::~VerilatedModule() {
-    if (m_namep) free((void*)m_namep); m_namep=NULL;
+    if (m_namep) { free((void*)m_namep); m_namep=NULL; }
 }

 //======================================================================
@@ -1287,7 +1340,7 @@ VerilatedVar* VerilatedScope::varFind(const char* namep) const {
    return NULL;
 }

-void* VerilatedScope::exportFindNullError(int funcnum) const {
+void* VerilatedScope::exportFindNullError(int funcnum) {
    // Slowpath - Called only when find has failed
    string msg = (string("Testbench C called '")
 		  +VerilatedImp::exportName(funcnum)
@@ -1,7 +1,7 @@
 // -*- mode: C++; c-file-style: "cc-mode" -*-
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder. This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder. This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License.
 // Version 2.0.
@@ -38,6 +38,7 @@
 #include <cstring>
 #include <cmath>
 // <iostream> avoided to reduce compile time
+// <map> avoided and instead in verilated_heavy.h to reduce compile time
 // <string> avoided and instead in verilated_heavy.h to reduce compile time
 using namespace std;

@@ -68,6 +69,7 @@ typedef void (*VerilatedVoidCb)(void);

 class SpTraceVcd;
 class SpTraceVcdCFile;
+class VerilatedScopeNameMap;
 class VerilatedVar;
 class VerilatedVarNameMap;
 class VerilatedVcd;
@@ -102,9 +104,9 @@ class VerilatedModule {
 private:
    const char*		m_namep;	///< Module name
    VerilatedModule();				///< N/A, always use named constructor below
-    VerilatedModule(const VerilatedModule& );	///< N/A, no copying modules
+    VerilatedModule(const VerilatedModule& );	///< N/A, no copy constructor
 public:
-    VerilatedModule(const char* namep);	///< Create module with given hierarchy name
+    explicit VerilatedModule(const char* namep);	///< Create module with given hierarchy name
    ~VerilatedModule();
    const char* name() const { return m_namep; }	///< Return name of module
 };
@@ -199,16 +201,16 @@ public:  // But internals only - called from VerilatedModule's
    inline VerilatedSyms* symsp() const { return m_symsp; }
    VerilatedVar* varFind(const char* namep) const;
    VerilatedVarNameMap* varsp() const { return m_varsp; }
-    void* exportFindError(int funcnum) const;
-    void* exportFindNullError(int funcnum) const;
    void scopeDump() const;
-    inline void* exportFind(int funcnum) const {
-	if (VL_UNLIKELY(!this)) return exportFindNullError(funcnum);
-	if (VL_LIKELY(funcnum < m_funcnumMax)) {
+    void* exportFindError(int funcnum) const;
+    static void* exportFindNullError(int funcnum);
+    static inline void* exportFind(const VerilatedScope* scopep, int funcnum) {
+	if (VL_UNLIKELY(!scopep)) return exportFindNullError(funcnum);
+	if (VL_LIKELY(funcnum < scopep->m_funcnumMax)) {
 	    // m_callbacksp must be declared, as Max'es are > 0
-	    return m_callbacksp[funcnum];
+	    return scopep->m_callbacksp[funcnum];
 	} else {
-	    return exportFindError(funcnum);
+	    return scopep->exportFindError(funcnum);
 	}
    }
 };
@@ -286,7 +288,9 @@ public:
    /// Record command line arguments, for retrieval by $test$plusargs/$value$plusargs
    static void commandArgs(int argc, const char** argv);
    static void commandArgs(int argc, char** argv) { commandArgs(argc,(const char**)argv); }
+    static void commandArgsAdd(int argc, const char** argv);
    static CommandArgValues* getCommandArgs() {return &s_args;}
+    /// Match plusargs with a given prefix. Returns static char* valid only for a single call
    static const char* commandArgsPlusMatch(const char* prefixp);

    /// Produce name & version for (at least) VPI
@@ -308,6 +312,7 @@ public:
    static const char* catName(const char* n1, const char* n2); // Returns new'ed data
    // Internal: Find scope
    static const VerilatedScope* scopeFind(const char* namep);
+    static const VerilatedScopeNameMap* scopeNameMap();
    // Internal: Get and set DPI context
    static const VerilatedScope* dpiScope() { return t_dpiScopep; }
    static void dpiScope(const VerilatedScope* scopep) { t_dpiScopep=scopep; }
@@ -357,6 +362,7 @@ extern IData VL_FOPEN_WI(int fnwords, WDataInP ofilename, IData mode);
 extern IData VL_FOPEN_QI(QData ofilename, IData mode);
 inline IData VL_FOPEN_II(IData ofilename, IData mode) { return VL_FOPEN_QI(ofilename,mode); }

+
 extern void VL_FCLOSE_I(IData fdi);

 extern void VL_READMEM_W(bool hex, int width, int depth, int array_lsb, int fnwords,
@@ -2,7 +2,7 @@
 ######################################################################
 # DESCRIPTION: Makefile commands for all verilated target files
 #
-# Copyright 2003-2015 by Wilson Snyder. Verilator is free software; you can
+# Copyright 2003-2017 by Wilson Snyder. Verilator is free software; you can
 # redistribute it and/or modify it under the terms of either the GNU Lesser
 # General Public License Version 3 or the Perl Artistic License Version 2.0.
 ######################################################################
@@ -43,8 +43,9 @@ VK_CPPFLAGS_ALWAYS += \
 		-I$(VERILATOR_ROOT)/include \
 		-I$(VERILATOR_ROOT)/include/vltstd \
 		-DVL_PRINTF=printf \
-		-DVM_TRACE=$(VM_TRACE) \
 		-DVM_COVERAGE=$(VM_COVERAGE) \
+		-DVM_SC=$(VM_SC) \
+		-DVM_TRACE=$(VM_TRACE) \
 		$(CFG_CXXFLAGS_NO_UNUSED) \

 ifeq ($(CFG_WITH_CCWARN),yes)	# Local... Else don't burden users
@@ -120,26 +121,13 @@ ifeq ($(VM_SP),1)
 	 $(SP_PREPROC) -M sp_preproc.d --tree $(VM_PREFIX).sp_tree \
 		--preproc $(VK_CLASSES_SP)
 else
- ifeq ($(VM_COVERAGE),1)
-  CPPFLAGS += -I$(SYSTEMPERL_INCLUDE)
-  VPATH    +=   $(SYSTEMPERL_INCLUDE)
- endif
  preproc:
 endif

-#######################################################################
-##### SystemC w/o SystemPerl builds
-
-ifeq ($(VM_SC),1)
-  LIBS   += -lm -lstdc++
-endif
-
 #######################################################################
 ##### C/H builds

-ifeq ($(VM_PCLI),1)
-  LIBS   += -lm -lstdc++
-endif
+LIBS   += -lm -lstdc++

 #######################################################################
 # Overall Objects Linking
@@ -175,16 +163,24 @@ $(VM_PREFIX)__ALL.a: $(VK_OBJS)
 ######################################################################
 ### Compile rules

-#Default rule embedded in make:  (Not defined so user makefiles can override it)
-#.cpp.o:
-#	$(CXX) $(CXXFLAGS) $(CPPFLAGS) -c -o $@ $<
-
+ifneq ($(VM_DEFAULT_RULES),0)
 $(VM_PREFIX)__ALLsup.o: $(VM_PREFIX)__ALLsup.cpp
 	$(OBJCACHE) $(CXX) $(CXXFLAGS) $(CPPFLAGS) $(OPT_SLOW) -c -o $@ $<

 $(VM_PREFIX)__ALLcls.o: $(VM_PREFIX)__ALLcls.cpp
 	$(OBJCACHE) $(CXX) $(CXXFLAGS) $(CPPFLAGS) $(OPT_FAST) -c -o $@ $<

+$(VM_PREFIX)%__Slow.o: $(VM_PREFIX)%__Slow.cpp
+	$(OBJCACHE) $(CXX) $(CXXFLAGS) $(CPPFLAGS) $(OPT_SLOW) -c -o $@ $<
+
+$(VM_PREFIX)%.o: $(VM_PREFIX)%.cpp
+	$(OBJCACHE) $(CXX) $(CXXFLAGS) $(CPPFLAGS) $(OPT_FAST) -c -o $@ $<
+endif
+
+#Default rule embedded in make:
+#.cpp.o:
+#	$(CXX) $(CXXFLAGS) $(CPPFLAGS) -c -o $@ $<
+
 ######################################################################
 ### Debugging

@@ -4,7 +4,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder. This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder. This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License.
 // Version 2.0.
@@ -1,7 +1,7 @@
 // -*- mode: C++; c-file-style: "cc-mode" -*-
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder. This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder. This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License.
 // Version 2.0.
@@ -3,7 +3,7 @@
 //
 // THIS MODULE IS PUBLICLY LICENSED
 //
-// Copyright 2001-2015 by Wilson Snyder.  This program is free software;
+// Copyright 2001-2017 by Wilson Snyder.  This program is free software;
 // you can redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License Version 2.0.
 //
@@ -75,6 +75,7 @@ public:
    virtual vluint64_t count() const { return *m_countp; }
    virtual void zero() const { *m_countp = 0; }
    // CONSTRUCTORS
+    // cppcheck-suppress noExplicitConstructor
    VerilatedCoverItemSpec(T* countp) : m_countp(countp) { zero(); }
    virtual ~VerilatedCoverItemSpec() {}
 };
@@ -261,8 +262,8 @@ public:
 	assert(m_insertp);
 	// First two key/vals are filename
 	ckeyps[0]="filename";	valps[0]=m_insertFilenamep;
-	VlCovCvtToCStr linestrp (m_insertLineno);
-	ckeyps[1]="lineno";	valps[1]=linestrp;
+	string linestr = vlCovCvtToStr(m_insertLineno);
+	ckeyps[1]="lineno";	valps[1]=linestr.c_str();
 	// Default page if not specified
 	const char* fnstartp = m_insertFilenamep;
 	while (const char* foundp = strchr(fnstartp,'/')) fnstartp=foundp+1;
@@ -440,8 +441,10 @@ void VerilatedCov::_insertp (A(0),A(1),A(2),A(3),A(4),A(5),A(6),A(7),A(8),A(9),
 // Backward compatibility for Verilator
 void VerilatedCov::_insertp (A(0), A(1),  K(2),int val2,  K(3),int val3,
 			     K(4),const string& val4,  A(5),A(6)) {
+    string val2str = vlCovCvtToStr(val2);
+    string val3str = vlCovCvtToStr(val3);
    _insertp(C(0),C(1),
-	     key2,VlCovCvtToCStr(val2),  key3,VlCovCvtToCStr(val3),  key4, val4.c_str(),
+	     key2,val2str.c_str(),  key3,val3str.c_str(),  key4, val4.c_str(),
 	     C(5),C(6),N(7),N(8),N(9),
 	     N(10),N(11),N(12),N(13),N(14),N(15),N(16),N(17),N(18),N(19),
 	     N(20),N(21),N(22),N(23),N(24),N(25),N(26),N(27),N(28),N(29));
@@ -3,7 +3,7 @@
 //
 // THIS MODULE IS PUBLICLY LICENSED
 //
-// Copyright 2001-2015 by Wilson Snyder.  This program is free software;
+// Copyright 2001-2017 by Wilson Snyder.  This program is free software;
 // you can redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License Version 2.0.
 //
@@ -78,19 +78,6 @@ template< class T> std::string vlCovCvtToStr (const T& t) {
    ostringstream os; os<<t; return os.str();
 }

-/// Usage: something(VlCovCvtToCStr(i))
-/// Note the pointer will only be valid for as long as the object remains
-/// in scope!
-struct VlCovCvtToCStr {
-    string m_str;
-    // Casters
-    template< class T> VlCovCvtToCStr (const T& t) {
-	ostringstream os; os<<t; m_str=os.str();
-    }
-    ~VlCovCvtToCStr() {}
-    operator const char* () const { return m_str.c_str(); };
-};
-
 //=============================================================================
 //  VerilatedCov
 ///  Verilator coverage global class
@@ -3,7 +3,7 @@
 //
 // THIS MODULE IS PUBLICLY LICENSED
 //
-// Copyright 2001-2015 by Wilson Snyder.  This program is free software;
+// Copyright 2001-2017 by Wilson Snyder.  This program is free software;
 // you can redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License Version 2.0.
 //
@@ -1,7 +1,7 @@
 // -*- mode: C++; c-file-style: "cc-mode" -*-
 //*************************************************************************
 //
-// Copyright 2009-2015 by Wilson Snyder. This program is free software; you can
+// Copyright 2009-2017 by Wilson Snyder. This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License.
 // Version 2.0.
@@ -1,7 +1,7 @@
 // -*- mode: C++; c-file-style: "cc-mode" -*-
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder. This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder. This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License.
 // Version 2.0.
@@ -1,7 +1,7 @@
 // -*- mode: C++; c-file-style: "cc-mode" -*-
 //*************************************************************************
 //
-// Copyright 2010-2015 by Wilson Snyder. This program is free software; you can
+// Copyright 2010-2017 by Wilson Snyder. This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License.
 // Version 2.0.
@@ -60,8 +60,12 @@ inline string VL_REPLICATEN_NNI(int obits,int lbits,int rbits, const string& lhs
    return VL_REPLICATEN_NNQ(obits,lbits,rbits,lhs,rep);
 }

+extern IData VL_FOPEN_NI(const string& filename, IData mode);
+extern void VL_READMEM_N(bool hex, int width, int depth, int array_lsb, int fnwords,
+                         const string& ofilename, void* memp, IData start, IData end);
 extern IData VL_SSCANF_INX(int lbits, const string& ld, const char* formatp, ...);
 extern void VL_SFORMAT_X(int obits_ignored, string &output, const char* formatp, ...);
 extern string VL_SFORMATF_NX(const char* formatp, ...);
+extern IData VL_VALUEPLUSARGS_IN(int rbits, const char* prefixp, char fmt, string& ldr);

 #endif // Guard
@@ -1,7 +1,7 @@
 // -*- mode: C++; c-file-style: "cc-mode" -*-
 //*************************************************************************
 //
-// Copyright 2009-2015 by Wilson Snyder. This program is free software; you can
+// Copyright 2009-2017 by Wilson Snyder. This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License.
 // Version 2.0.
@@ -49,7 +49,6 @@ class VerilatedImp {
    // TYPES
    typedef vector<string> ArgVec;
    typedef map<pair<const void*,void*>,void*> UserMap;
-    typedef map<const char*, const VerilatedScope*, VerilatedCStrCmp>  ScopeNameMap;
    typedef map<const char*, int, VerilatedCStrCmp>  ExportNameMap;

    // MEMBERS
@@ -60,7 +59,7 @@ class VerilatedImp {
    ArgVec		m_argVec;	///< Argument list (NOT save-restored, may want different results)
    bool		m_argVecLoaded;	///< Ever loaded argument list
    UserMap	 	m_userMap;	///< Map of <(scope,userkey), userData>
-    ScopeNameMap	m_nameMap;	///< Map of <scope_name, scope pointer>
+    VerilatedScopeNameMap	m_nameMap;	///< Map of <scope_name, scope pointer>
    // Slow - somewhat static:
    ExportNameMap	m_exportMap;	///< Map of <export_func_proto, func number>
    int			m_exportNext;	///< Next export funcnum
@@ -93,7 +92,11 @@ public: // But only for verilated*.cpp

    // METHODS - arguments
    static void commandArgs(int argc, const char** argv) {
-	s_s.m_argVec.clear();
+	s_s.m_argVec.clear();  // Always clear
+	commandArgsAdd(argc, argv);
+    }
+    static void commandArgsAdd(int argc, const char** argv) {
+	if (!s_s.m_argVecLoaded) s_s.m_argVec.clear();
 	for (int i=0; i<argc; i++) s_s.m_argVec.push_back(argv[i]);
 	s_s.m_argVecLoaded = true; // Can't just test later for empty vector, no arguments is ok
    }
@@ -154,30 +157,33 @@ public: // But only for verilated*.cpp
    // METHODS - scope name
    static void scopeInsert(const VerilatedScope* scopep) {
 	// Slow ok - called once/scope at construction
-	ScopeNameMap::iterator it=s_s.m_nameMap.find(scopep->name());
+	VerilatedScopeNameMap::iterator it=s_s.m_nameMap.find(scopep->name());
 	if (it == s_s.m_nameMap.end()) {
 	    s_s.m_nameMap.insert(it, make_pair(scopep->name(),scopep));
 	}
    }
    static inline const VerilatedScope* scopeFind(const char* namep) {
-	ScopeNameMap::iterator it=s_s.m_nameMap.find(namep);
+	VerilatedScopeNameMap::iterator it=s_s.m_nameMap.find(namep);
 	if (VL_LIKELY(it != s_s.m_nameMap.end())) return it->second;
 	else return NULL;
    }
    static void scopeErase(const VerilatedScope* scopep) {
 	// Slow ok - called once/scope at destruction
 	userEraseScope(scopep);
-	ScopeNameMap::iterator it=s_s.m_nameMap.find(scopep->name());
+	VerilatedScopeNameMap::iterator it=s_s.m_nameMap.find(scopep->name());
 	if (it != s_s.m_nameMap.end()) s_s.m_nameMap.erase(it);
    }
    static void scopesDump() {
 	VL_PRINTF("  scopesDump:\n");
-	for (ScopeNameMap::iterator it=s_s.m_nameMap.begin(); it!=s_s.m_nameMap.end(); ++it) {
+	for (VerilatedScopeNameMap::iterator it=s_s.m_nameMap.begin(); it!=s_s.m_nameMap.end(); ++it) {
 	    const VerilatedScope* scopep = it->second;
 	    scopep->scopeDump();
 	}
 	VL_PRINTF("\n");
    }
+    static const VerilatedScopeNameMap* scopeNameMap() {
+        return &s_s.m_nameMap;
+    }

 public: // But only for verilated*.cpp
    // METHODS - export names
@@ -3,7 +3,7 @@
 //
 // THIS MODULE IS PUBLICLY LICENSED
 //
-// Copyright 2001-2015 by Wilson Snyder.  This program is free software;
+// Copyright 2001-2017 by Wilson Snyder.  This program is free software;
 // you can redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License Version 2.0.
 //
@@ -201,7 +201,7 @@ void VerilatedRestore::fill() {
    if (VL_UNLIKELY(!isOpen())) return;
    // Move remaining characters down to start of buffer.  (No memcpy, overlaps allowed)
    vluint8_t* rp = m_bufp;
-    for (vluint8_t* sp=m_cp; rp < m_endp;) *rp++ = *sp++;  // Overlaps
+    for (vluint8_t* sp=m_cp; sp < m_endp;) *rp++ = *sp++;  // Overlaps
    m_endp = m_bufp + (m_endp - m_cp);
    m_cp = m_bufp; // Reset buffer
    // Read into buffer starting at m_endp 
@@ -3,7 +3,7 @@
 //
 // THIS MODULE IS PUBLICLY LICENSED
 //
-// Copyright 2012-2015 by Wilson Snyder.  This program is free software;
+// Copyright 2012-2017 by Wilson Snyder.  This program is free software;
 // you can redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License Version 2.0.
 //
@@ -48,6 +48,8 @@ protected:
 	m_bufp = new vluint8_t [bufferSize()];
 	m_cp = m_bufp;
    }
+private:
+    VerilatedSerialBase(const VerilatedSerialBase& );	///< N/A, no copy constructor
 public:
    // CREATORS
    virtual ~VerilatedSerialBase() {
@@ -223,7 +225,7 @@ inline VerilatedSerialize&   operator<<(VerilatedSerialize& os,   string& rhs) {
    return os.write(rhs.data(), len);
 }
 inline VerilatedDeserialize& operator>>(VerilatedDeserialize& os, string& rhs) {
-    vluint32_t len;
+    vluint32_t len=0;
    os>>len;
    rhs.resize(len);
    return os.read((void*)rhs.data(), len);
@@ -1,7 +1,7 @@
 // -*- mode: C++; c-file-style: "cc-mode" -*-
 //*************************************************************************
 //
-// Copyright 2009-2015 by Wilson Snyder. This program is free software; you can
+// Copyright 2009-2017 by Wilson Snyder. This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License.
 // Version 2.0.
@@ -1,7 +1,7 @@
 // -*- mode: C++; c-file-style: "cc-mode" -*-
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder. This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder. This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License.
 // Version 2.0.
@@ -32,16 +32,6 @@

 #include <map>

-//======================================================================
-// Types
-
-struct VerilatedCStrCmp {
-    /// Ordering maps keyed by const char*'s
-    bool operator() (const char *a, const char *b) const {
-	return std::strcmp(a, b) < 0;
-    }
-};
-
 //===========================================================================
 /// Verilator range

@@ -93,6 +83,20 @@ public:
 //======================================================================
 /// Types

+struct VerilatedCStrCmp {
+    /// Ordering maps keyed by const char*'s
+    bool operator() (const char *a, const char *b) const {
+	return std::strcmp(a, b) < 0;
+    }
+};
+
+class VerilatedScopeNameMap
+    : public map<const char*, const VerilatedScope*, VerilatedCStrCmp> {
+public:
+    VerilatedScopeNameMap() {}
+    ~VerilatedScopeNameMap() {}
+};
+
 class VerilatedVarNameMap : public map<const char*, VerilatedVar, VerilatedCStrCmp> {
 public:
    VerilatedVarNameMap() {}
@@ -3,7 +3,7 @@
 //
 // THIS MODULE IS PUBLICLY LICENSED
 //
-// Copyright 2001-2015 by Wilson Snyder.  This program is free software;
+// Copyright 2001-2017 by Wilson Snyder.  This program is free software;
 // you can redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License Version 2.0.
 //
@@ -378,7 +378,7 @@ string VerilatedVcd::doubleToTimescale (double value) {
    else if (value>=1e-12) { suffixp="ps"; value *= 1e12; }
    else if (value>=1e-15) { suffixp="fs"; value *= 1e15; }
    else if (value>=1e-18) { suffixp="as"; value *= 1e18; }
-    char valuestr[100]; sprintf(valuestr,"%d%s",(int)(value), suffixp);
+    char valuestr[100]; sprintf(valuestr,"%3.0f%s", value, suffixp);
    return valuestr;  // Gets converted to string, so no ref to stack
 }

@@ -3,7 +3,7 @@
 //
 // THIS MODULE IS PUBLICLY LICENSED
 //
-// Copyright 2001-2015 by Wilson Snyder.  This program is free software;
+// Copyright 2001-2017 by Wilson Snyder.  This program is free software;
 // you can redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License Version 2.0.
 //
@@ -144,13 +144,15 @@ private:
 	return out + ((char)((code)%94+33));
    }

+    VerilatedVcd(const VerilatedVcd& );	///< N/A, no copy constructor
+
 protected:
    // METHODS
    void evcd(bool flag) { m_evcd = flag; }

 public:
    // CREATORS
-    VerilatedVcd(VerilatedVcdFile* filep=NULL);
+    explicit VerilatedVcd(VerilatedVcdFile* filep=NULL);
    ~VerilatedVcd();

    // ACCESSORS
@@ -399,7 +401,7 @@ class VerilatedVcdC {
    VerilatedVcd		m_sptrace;	///< Trace file being created
 public:
    // CONSTRUCTORS
-    VerilatedVcdC(VerilatedVcdFile* filep=NULL) : m_sptrace(filep) {}
+    explicit VerilatedVcdC(VerilatedVcdFile* filep=NULL) : m_sptrace(filep) {}
    ~VerilatedVcdC() {}
    // ACCESSORS
    /// Is file open?
@@ -3,7 +3,7 @@
 //
 // THIS MODULE IS PUBLICLY LICENSED
 //
-// Copyright 2001-2015 by Wilson Snyder.  This program is free software;
+// Copyright 2001-2017 by Wilson Snyder.  This program is free software;
 // you can redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License Version 2.0.
 //
@@ -30,6 +30,7 @@
 //--------------------------------------------------
 #if (SYSTEMC_VERSION>=20050714)
    // SystemC 2.1.v1
+// cppcheck-suppress unusedFunction
 void VerilatedVcdSc::write_comment (const std::string &) {}
 void VerilatedVcdSc::trace (const unsigned int &, const std::string &, const char **) {}

@@ -74,6 +75,7 @@ void VerilatedVcdSc::trace (const unsigned int &, const std::string &, const cha
 //--------------------------------------------------
 #elif (SYSTEMC_VERSION>20011000)
    // SystemC 2.0.1
+// cppcheck-suppress unusedFunction
 void VerilatedVcdSc::write_comment (const sc_string &) {}
 void VerilatedVcdSc::trace (const unsigned int &, const sc_string &, const char **) {}

@@ -116,6 +118,7 @@ void VerilatedVcdSc::trace (const unsigned int &, const sc_string &, const char
 //--------------------------------------------------
 #else
    // SystemC 1.2.1beta
+// cppcheck-suppress unusedFunction
 void VerilatedVcdSc::write_comment (const sc_string &) {}
 void VerilatedVcdSc::trace (const unsigned int &, const sc_string &, const char **) {}

@@ -3,7 +3,7 @@
 //
 // THIS MODULE IS PUBLICLY LICENSED
 //
-// Copyright 2001-2015 by Wilson Snyder.  This program is free software;
+// Copyright 2001-2017 by Wilson Snyder.  This program is free software;
 // you can redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License Version 2.0.
 //
@@ -1,7 +1,7 @@
 // -*- mode: C++; c-file-style: "cc-mode" -*-
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder. This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder. This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License.
 // Version 2.0.
@@ -95,6 +95,12 @@
 // This is not necessarily the same as #UL, depending on what the IData typedef is.
 #define VL_UL(c) ((IData)(c##UL))	///< Add appropriate suffix to 32-bit constant

+#ifdef VL_CPPCHECK
+# define VL_DANGLING(v)
+#else
+# define VL_DANGLING(v) do { (v) = NULL; } while(0)	///< After e.g. delete, set variable to NULL to indicate must not use later
+#endif
+
 //=========================================================================
 // C++-2011

@@ -207,19 +213,15 @@ typedef unsigned long long	vluint64_t;	///< 64-bit unsigned type
 # endif
 #endif

-#ifdef _WIN32
-# define VL_VSNPRINTF vl_vsnprintf
-inline int vl_vsnprintf(char* str, size_t size, const char* format, va_list ap) {
-    int count = -1;
-    if (size != 0) {
-        count = _vsnprintf_s(str, size, _TRUNCATE, format, ap);
-    }
-    if (count == -1) {
-        count = _vscprintf(format, ap);
-    }
-    return count;
-}
+#if defined(_WIN32) && defined(_MSC_VER)
+# if (_MSC_VER < 1900)
+#  define VL_SNPRINTF _snprintf
+# else
+#  define VL_SNPRINTF snprintf
+# endif
+# define VL_VSNPRINTF vsnprintf
 #else
+# define VL_SNPRINTF snprintf
 # define VL_VSNPRINTF vsnprintf
 #endif

@@ -785,7 +785,7 @@ in C<src/Makefile_obj.in> and reconfigure.

 The latest version is available from L<http://www.veripool.org/>.

-Copyright 2008-2015 by Wilson Snyder.  Verilator is free software; you can
+Copyright 2008-2017 by Wilson Snyder.  Verilator is free software; you can
 redistribute it and/or modify it under the terms of either the GNU Lesser
 General Public License Version 3 or the Perl Artistic License Version 2.0.

@@ -1,7 +1,7 @@
 #!/usr/bin/perl -w
 ######################################################################
 #
-# Copyright 2007-2015 by Wilson Snyder.  This package is free software; you
+# Copyright 2007-2017 by Wilson Snyder.  This package is free software; you
 # can redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
@@ -1,7 +1,7 @@
 #!/usr/bin/perl -w
 ######################################################################
 #
-# Copyright 2007-2015 by Wilson Snyder.  This package is free software; you
+# Copyright 2007-2017 by Wilson Snyder.  This package is free software; you
 # can redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
@@ -143,7 +143,7 @@ Displays this message and program version and exits.

 =head1 DISTRIBUTION

-Copyright 2005-2015 by Wilson Snyder.  Verilator is free software; you can
+Copyright 2005-2017 by Wilson Snyder.  Verilator is free software; you can
 redistribute it and/or modify it under the terms of either the GNU Lesser
 General Public License Version 3 or the Perl Artistic License Version 2.0.

@@ -184,7 +184,7 @@ Displays this message and program version and exits.

 =head1 DISTRIBUTION

-Copyright 2005-2015 by Wilson Snyder.  Verilator is free software; you can
+Copyright 2005-2017 by Wilson Snyder.  Verilator is free software; you can
 redistribute it and/or modify it under the terms of either the GNU Lesser
 General Public License Version 3 or the Perl Artistic License Version 2.0.

@@ -1,7 +1,7 @@
 #!/usr/bin/perl -w
 ######################################################################
 #
-# Copyright 2007-2015 by Wilson Snyder.  This package is free software; you
+# Copyright 2007-2017 by Wilson Snyder.  This package is free software; you
 # can redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
@@ -115,7 +115,8 @@ sub write_verilog {

 sub cleanenv {
    foreach my $var (keys %ENV) {
-	if ($var eq "VERILATOR_ROOT") {
+	if ($var eq "VERILATOR_ROOT"
+	    || $var eq "VERILATOR_INCLUDE") {
 	    print "unset $var # Was '$ENV{$var}'\n";
 	    delete $ENV{$var}
 	}
@@ -183,7 +184,7 @@ Runs a specific test stage (see the script).

 =head1 DISTRIBUTION

-Copyright 2009-2015 by Wilson Snyder.  This package is free software; you
+Copyright 2009-2017 by Wilson Snyder.  This package is free software; you
 can redistribute it and/or modify it under the terms of either the GNU
 Lesser General Public License Version 3 or the Perl Artistic License
 Version 2.0.
@@ -28,7 +28,7 @@ invoke_atsim - Invoke tool under "modules" command

 =head1 DISTRIBUTION

-Copyright 2005-2015 by Wilson Snyder.  This package is free software; you
+Copyright 2005-2017 by Wilson Snyder.  This package is free software; you
 can redistribute it and/or modify it under the terms of either the GNU
 Lesser General Public License Version 3 or the Perl Artistic License
 Version 2.0.
@@ -28,7 +28,7 @@ invoke_iccr - Invoke tool under "modules" command

 =head1 DISTRIBUTION

-Copyright 2007-2015 by Wilson Snyder.  This package is free software; you
+Copyright 2007-2017 by Wilson Snyder.  This package is free software; you
 can redistribute it and/or modify it under the terms of either the GNU
 Lesser General Public License Version 3 or the Perl Artistic License
 Version 2.0.
@@ -28,7 +28,7 @@ invoke_ncverilog - Invoke tool under "modules" command

 =head1 DISTRIBUTION

-Copyright 2005-2015 by Wilson Snyder.  This package is free software; you
+Copyright 2005-2017 by Wilson Snyder.  This package is free software; you
 can redistribute it and/or modify it under the terms of either the GNU
 Lesser General Public License Version 3 or the Perl Artistic License
 Version 2.0.
@@ -28,7 +28,7 @@ invoke_vcs - Invoke tool under "modules" command

 =head1 DISTRIBUTION

-Copyright 2005-2015 by Wilson Snyder.  This package is free software; you
+Copyright 2005-2017 by Wilson Snyder.  This package is free software; you
 can redistribute it and/or modify it under the terms of either the GNU
 Lesser General Public License Version 3 or the Perl Artistic License
 Version 2.0.
@@ -331,7 +331,7 @@ Displays this message and program version and exits.

 =head1 DISTRIBUTION

-Copyright 2005-2015 by Wilson Snyder.  Verilator is free software; you can
+Copyright 2005-2017 by Wilson Snyder.  Verilator is free software; you can
 redistribute it and/or modify it under the terms of either the GNU Lesser
 General Public License Version 3 or the Perl Artistic License Version 2.0.

@@ -1,6 +1,6 @@
 # DESCRIPTION: Verilator: GDB startup file with useful defines
 #
-# Copyright 2012-2015 by Wilson Snyder. This program is free software; you can
+# Copyright 2012-2017 by Wilson Snyder. This program is free software; you can
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
@@ -7,7 +7,7 @@
 #
 #*****************************************************************************
 #
-# Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+# Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
@@ -46,6 +46,8 @@ obj_opt:
 obj_dbg:
 	mkdir $@

+.SUFFIXES:
+
 .PHONY: ../verilator_bin ../verilator_bin_dbg ../verilator_coverage_bin_dbg

 opt: ../verilator_bin
@@ -7,7 +7,7 @@
 #
 #*****************************************************************************
 #
-# Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+# Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
@@ -99,6 +99,8 @@ CPPFLAGS += -MP # Only works on recent GCC versions
 ifeq ($(CFG_WITH_CCWARN),yes)	# Local... Else don't burden users
 CPPFLAGS += -W -Wall $(CFG_CXXFLAGS_SRC) -Werror
 #CPPFLAGS += -pedantic-errors
+else
+CPPFLAGS += $(CFG_CXXFLAGS_SRC)
 endif
 CPPFLAGSWALL   = $(CPPFLAGS)
 CPPFLAGSPARSER = $(CPPFLAGS) $(CFG_CXXFLAGS_PARSER)
@@ -164,6 +166,7 @@ RAW_OBJS = \
 	V3Begin.o \
 	V3Branch.o \
 	V3Broken.o \
+	V3CCtors.o \
 	V3Case.o \
 	V3Cast.o \
 	V3Cdc.o \
@@ -299,7 +302,7 @@ serial:: V3Ast__gen_classes.h V3ParseBison.c

 serial_vlcov:: vlcovgen.d

-vlcovgen.d: $(VLCOVGEN) $(srcdir)/include/verilated_cov_key.h
+vlcovgen.d: $(VLCOVGEN) $(srcdir)/../include/verilated_cov_key.h
 	$(PERL) $(VLCOVGEN) --srcdir $(srcdir)
 	touch $@

@@ -327,6 +330,8 @@ V3PreLex_pregen.yy.cpp:	V3PreLex.l $(HEADERS)
 V3PreLex.yy.cpp: V3PreLex_pregen.yy.cpp $(FLEXFIX)
 	$(PERL) $(FLEXFIX) V3PreLex <$< >$@

+.SUFFIXES:
+
 ######################################################################
 ######################################################################

@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -73,7 +73,7 @@ private:
 	m_scopep->addActivep(nodep);
    }
    // VISITORS
-    virtual void visit(AstScope* nodep, AstNUser*) {
+    virtual void visit(AstScope* nodep) {
 	m_scopep = nodep;
 	m_iActivep = NULL;
 	m_cActivep = NULL;
@@ -81,15 +81,15 @@ private:
 	nodep->iterateChildren(*this);
 	// Don't clear scopep, the namer persists beyond this visit
    }
-    virtual void visit(AstSenTree* nodep, AstNUser*) {
+    virtual void visit(AstSenTree* nodep) {
 	// Simplify sensitivity list
-	V3Const::constifyExpensiveEdit(nodep); nodep=NULL;
+	V3Const::constifyExpensiveEdit(nodep); VL_DANGLING(nodep);
    }
    // Empty visitors, speed things up
-    virtual void visit(AstNodeStmt* nodep, AstNUser*) { }
+    virtual void visit(AstNodeStmt* nodep) { }
    //--------------------
    // Default
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	// Default: Just iterate
 	nodep->iterateChildren(*this);
    }
@@ -169,7 +169,7 @@ private:
    AstNode*	m_alwaysp;	// Always we're under
    AstNode*	m_assignp;	// In assign
    // VISITORS
-    virtual void visit(AstAssignDly* nodep, AstNUser*) {
+    virtual void visit(AstAssignDly* nodep) {
 	if (m_check != CT_SEQ) {
 	    // Convert to a non-delayed assignment
 	    UINFO(5,"    ASSIGNDLY "<<nodep<<endl);
@@ -184,10 +184,10 @@ private:
 					   nodep->lhsp()->unlinkFrBack(),
 					   nodep->rhsp()->unlinkFrBack());
 	    nodep->replaceWith(newp);
-	    nodep->deleteTree(); nodep = NULL;
+	    nodep->deleteTree(); VL_DANGLING(nodep);
 	}
    }
-    virtual void visit(AstAssign* nodep, AstNUser*) {
+    virtual void visit(AstAssign* nodep) {
 	if (m_check == CT_SEQ) {
 	    AstNode* las = m_assignp;
 	    m_assignp = nodep;
@@ -195,7 +195,7 @@ private:
 	    m_assignp = las;
 	}
    }
-    virtual void visit(AstVarRef* nodep, AstNUser*) {
+    virtual void visit(AstVarRef* nodep) {
 	AstVar* varp=nodep->varp();
 	if (m_check == CT_SEQ
 	    && m_assignp
@@ -214,7 +214,7 @@ private:
 	}
    }
    //--------------------
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }
 public:
@@ -244,7 +244,7 @@ private:
    bool	m_itemSequent;	// Found a SenItem sequential

    // VISITORS
-    virtual void visit(AstScope* nodep, AstNUser*) {
+    virtual void visit(AstScope* nodep) {
 	// Create required actives and add to scope
 	UINFO(4," SCOPE   "<<nodep<<endl);
 	// Clear last scope's names, and collect this scope's existing names
@@ -252,10 +252,10 @@ private:
 	m_scopeFinalp = NULL;
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstActive* nodep, AstNUser*) {
+    virtual void visit(AstActive* nodep) {
 	// Actives are being formed, so we can ignore any already made
    }
-    virtual void visit(AstInitial* nodep, AstNUser*) {
+    virtual void visit(AstInitial* nodep) {
 	// Relink to IACTIVE, unless already under it
 	UINFO(4,"    INITIAL "<<nodep<<endl);
 	ActiveDlyVisitor dlyvisitor (nodep, ActiveDlyVisitor::CT_INITIAL);
@@ -263,32 +263,32 @@ private:
 	nodep->unlinkFrBack();
 	wantactivep->addStmtsp(nodep);
    }
-    virtual void visit(AstAssignAlias* nodep, AstNUser*) {
+    virtual void visit(AstAssignAlias* nodep) {
 	// Relink to CACTIVE, unless already under it
 	UINFO(4,"    ASSIGNW "<<nodep<<endl);
 	AstActive* wantactivep = m_namer.getCActive(nodep->fileline());
 	nodep->unlinkFrBack();
 	wantactivep->addStmtsp(nodep);
    }
-    virtual void visit(AstAssignW* nodep, AstNUser*) {
+    virtual void visit(AstAssignW* nodep) {
 	// Relink to CACTIVE, unless already under it
 	UINFO(4,"    ASSIGNW "<<nodep<<endl);
 	AstActive* wantactivep = m_namer.getCActive(nodep->fileline());
 	nodep->unlinkFrBack();
 	wantactivep->addStmtsp(nodep);
    }
-    virtual void visit(AstCoverToggle* nodep, AstNUser*) {
+    virtual void visit(AstCoverToggle* nodep) {
 	// Relink to CACTIVE, unless already under it
 	UINFO(4,"    COVERTOGGLE "<<nodep<<endl);
 	AstActive* wantactivep = m_namer.getCActive(nodep->fileline());
 	nodep->unlinkFrBack();
 	wantactivep->addStmtsp(nodep);
    }
-    virtual void visit(AstFinal* nodep, AstNUser*) {
+    virtual void visit(AstFinal* nodep) {
 	// Relink to CFUNC for the final
 	UINFO(4,"    FINAL "<<nodep<<endl);
 	if (!nodep->bodysp()) { // Empty, Kill it.
-	    nodep->unlinkFrBack()->deleteTree(); nodep=NULL;
+	    nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
 	    return;
 	}
 	ActiveDlyVisitor dlyvisitor (nodep, ActiveDlyVisitor::CT_INITIAL);
@@ -304,7 +304,7 @@ private:
 	nodep->unlinkFrBack();
 	m_scopeFinalp->addStmtsp(new AstComment(nodep->fileline(), nodep->typeName()));
 	m_scopeFinalp->addStmtsp(nodep->bodysp()->unlinkFrBackWithNext());
-	nodep->deleteTree(); nodep = NULL;
+	nodep->deleteTree(); VL_DANGLING(nodep);
    }

    // METHODS
@@ -316,7 +316,7 @@ private:
 	    && oldsensesp->sensesp()->castSenItem()->isNever()) {
 	    // Never executing.  Kill it.
 	    if (oldsensesp->sensesp()->nextp()) nodep->v3fatalSrc("Never senitem should be alone, else the never should be eliminated.");
-	    nodep->unlinkFrBack()->deleteTree(); nodep=NULL;
+	    nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
 	    return;
 	}

@@ -329,7 +329,9 @@ private:

 	if (!combo && !sequent) combo=true;	// If no list, Verilog 2000: always @ (*)
 	if (combo && sequent) {
-	    nodep->v3error("Unsupported: Mixed edge (pos/negedge) and activity (no edge) sensitive activity list");
+	    if (!v3Global.opt.bboxUnsup()) {
+		nodep->v3error("Unsupported: Mixed edge (pos/negedge) and activity (no edge) sensitive activity list");
+	    }
 	    sequent = false;
 	}

@@ -351,7 +353,7 @@ private:

 	// Delete sensitivity list
 	if (oldsensesp) {
-	    oldsensesp->unlinkFrBackWithNext()->deleteTree(); oldsensesp=NULL;
+	    oldsensesp->unlinkFrBackWithNext()->deleteTree(); VL_DANGLING(oldsensesp);
 	}

 	// Move node to new active
@@ -370,25 +372,25 @@ private:
 	    ActiveDlyVisitor dlyvisitor (nodep, ActiveDlyVisitor::CT_SEQ);
 	}
    }
-    virtual void visit(AstAlways* nodep, AstNUser*) {
+    virtual void visit(AstAlways* nodep) {
 	// Move always to appropriate ACTIVE based on its sense list
 	UINFO(4,"    ALW   "<<nodep<<endl);
 	//if (debug()>=9) nodep->dumpTree(cout,"  Alw: ");

 	if (!nodep->bodysp()) {
 	    // Empty always.  Kill it.
-	    nodep->unlinkFrBack()->deleteTree(); nodep=NULL;
+	    nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
 	    return;
 	}
 	visitAlways(nodep, nodep->sensesp(), nodep->keyword());
    }
-    virtual void visit(AstAlwaysPublic* nodep, AstNUser*) {
+    virtual void visit(AstAlwaysPublic* nodep) {
 	// Move always to appropriate ACTIVE based on its sense list
 	UINFO(4,"    ALWPub   "<<nodep<<endl);
 	//if (debug()>=9) nodep->dumpTree(cout,"  Alw: ");
 	visitAlways(nodep, nodep->sensesp(), VAlwaysKwd::ALWAYS);
    }
-    virtual void visit(AstSenGate* nodep, AstNUser*) {
+    virtual void visit(AstSenGate* nodep) {
 	AstSenItem* subitemp = nodep->sensesp();
 	if (subitemp->edgeType() != AstEdgeType::ET_ANYEDGE
 	    && subitemp->edgeType() != AstEdgeType::ET_POSEDGE
@@ -397,12 +399,12 @@ private:
 	}
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstSenItem* nodep, AstNUser*) {
+    virtual void visit(AstSenItem* nodep) {
 	if (nodep->edgeType() == AstEdgeType::ET_ANYEDGE) {
 	    m_itemCombo = true;
 	    // Delete the sensitivity
 	    // We'll add it as a generic COMBO SenItem in a moment.
-	    nodep->unlinkFrBack()->deleteTree(); nodep=NULL;
+	    nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
 	} else if (nodep->varrefp()) {
 	    // V3LinkResolve should have cleaned most of these up
 	    if (!nodep->varrefp()->width1()) nodep->v3error("Unsupported: Non-single bit wide signal pos/negedge sensitivity: "
@@ -413,15 +415,15 @@ private:
    }

    // Empty visitors, speed things up
-    virtual void visit(AstNodeMath* nodep, AstNUser*) {}
-    virtual void visit(AstVarScope* nodep, AstNUser*) {}
+    virtual void visit(AstNodeMath* nodep) {}
+    virtual void visit(AstVarScope* nodep) {}
    //--------------------
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }
 public:
    // CONSTUCTORS
-    ActiveVisitor(AstNetlist* nodep) {
+    explicit ActiveVisitor(AstNetlist* nodep) {
 	m_scopeFinalp = NULL;
 	m_itemCombo = false;
 	m_itemSequent = false;
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -65,19 +65,19 @@ private:
    }

    // VISITORS
-    virtual void visit(AstTopScope* nodep, AstNUser*) {
+    virtual void visit(AstTopScope* nodep) {
 	m_topscopep = nodep;
 	m_finder.main(m_topscopep);
 	nodep->iterateChildren(*this);
 	m_topscopep = NULL;
    }
-    virtual void visit(AstNodeModule* nodep, AstNUser*) {
+    virtual void visit(AstNodeModule* nodep) {
 	// Create required actives and add to module
 	// We can start ordering at a module, or a scope
 	UINFO(4," MOD   "<<nodep<<endl);
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstActive* nodep, AstNUser*) {
+    virtual void visit(AstActive* nodep) {
 	UINFO(4,"   ACTIVE "<<nodep<<endl);
 	V3Const::constifyExpensiveEdit(nodep); // Remove duplicate clocks and such; sensesp() may change!
 	AstSenTree* sensesp = nodep->sensesp();
@@ -87,7 +87,7 @@ private:
 	    && sensesp->sensesp()->castSenItem()->isNever()) {
 	    // Never executing.  Kill it.
 	    if (sensesp->sensesp()->nextp()) nodep->v3fatalSrc("Never senitem should be alone, else the never should be eliminated.");
-	    nodep->unlinkFrBack()->deleteTree(); nodep=NULL;
+	    nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
 	    return;
 	}
 	// Copy combo tree to settlement tree with duplicated statements
@@ -120,34 +120,34 @@ private:
 	// No need to do statements under it, they're already moved.
 	//nodep->iterateChildren(*this);
    }
-    virtual void visit(AstInitial* nodep, AstNUser*) {
+    virtual void visit(AstInitial* nodep) {
 	nodep->v3fatalSrc("Node should have been under ACTIVE");
    }
-    virtual void visit(AstAssignAlias* nodep, AstNUser*) {
+    virtual void visit(AstAssignAlias* nodep) {
 	nodep->v3fatalSrc("Node should have been under ACTIVE");
    }
-    virtual void visit(AstAssignW* nodep, AstNUser*) {
+    virtual void visit(AstAssignW* nodep) {
 	nodep->v3fatalSrc("Node should have been under ACTIVE");
    }
-    virtual void visit(AstAlways* nodep, AstNUser*) {
+    virtual void visit(AstAlways* nodep) {
 	nodep->v3fatalSrc("Node should have been under ACTIVE");
    }
-    virtual void visit(AstAlwaysPublic* nodep, AstNUser*) {
+    virtual void visit(AstAlwaysPublic* nodep) {
 	nodep->v3fatalSrc("Node should have been under ACTIVE");
    }
-    virtual void visit(AstFinal* nodep, AstNUser*) {
+    virtual void visit(AstFinal* nodep) {
 	nodep->v3fatalSrc("Node should have been deleted");
    }
    // Empty visitors, speed things up
-    virtual void visit(AstNodeMath* nodep, AstNUser*) {}
-    virtual void visit(AstVarScope* nodep, AstNUser*) {}
+    virtual void visit(AstNodeMath* nodep) {}
+    virtual void visit(AstVarScope* nodep) {}
    //--------------------
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }
 public:
    // CONSTUCTORS
-    ActiveTopVisitor(AstNetlist* nodep) {
+    explicit ActiveTopVisitor(AstNetlist* nodep) {
 	m_topscopep = NULL;
 	nodep->accept(*this);
    }
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2005-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2005-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -138,7 +138,7 @@ private:
 	    nodep->replaceWith(newp);
 	}
 	// Bye
-	pushDeletep(nodep); nodep=NULL;
+	pushDeletep(nodep); VL_DANGLING(nodep);
    }

    void newVAssertion(AstVAssert* nodep, AstNode* propp) {
@@ -160,10 +160,10 @@ private:
 	// Install it
 	nodep->replaceWith(newp);
 	// Bye
-	pushDeletep(nodep); nodep=NULL;
+	pushDeletep(nodep); VL_DANGLING(nodep);
    }
    
-    virtual void visit(AstIf* nodep, AstNUser*) {
+    virtual void visit(AstIf* nodep) {
 	if (nodep->user1SetOnce()) return;
 	if (nodep->uniquePragma() || nodep->unique0Pragma()) {
 	    AstNodeIf* ifp = nodep;
@@ -205,8 +205,8 @@ private:
 	    // Note: if this ends with an 'else', then we don't need to validate that one of the
 	    // predicates evaluates to true.
 	    AstNode* ohot = ((allow_none || hasDefaultElse)
-			     ? (new AstOneHot0(nodep->fileline(), propp))->castNode()
-			     : (new AstOneHot (nodep->fileline(), propp))->castNode());
+			     ? static_cast<AstNode*>(new AstOneHot0(nodep->fileline(), propp))
+			     : static_cast<AstNode*>(new AstOneHot (nodep->fileline(), propp)));
 	    AstIf* checkifp = new AstIf (nodep->fileline(),
 					 new AstLogNot (nodep->fileline(), ohot),
 					 newFireAssert(nodep, "'unique if' statement violated"),
@@ -220,7 +220,7 @@ private:
    }

    // VISITORS  //========== Case assertions
-    virtual void visit(AstCase* nodep, AstNUser*) {
+    virtual void visit(AstCase* nodep) {
 	nodep->iterateChildren(*this);
 	if (!nodep->user1SetOnce()) {
 	    bool has_default=false;
@@ -245,17 +245,34 @@ private:
 		    AstNode* propp = NULL;
 		    for (AstCaseItem* itemp = nodep->itemsp(); itemp; itemp=itemp->nextp()->castCaseItem()) {
 			for (AstNode* icondp = itemp->condsp(); icondp!=NULL; icondp=icondp->nextp()) {
-			    AstNode* onep = new AstEq(icondp->fileline(),
-						      nodep->exprp()->cloneTree(false),
-						      icondp->cloneTree(false));
+			    AstNode* onep;
+			    AstConst* iconstp = icondp->castConst();
+			    if (iconstp && iconstp->num().isFourState()
+				&& (nodep->casex() || nodep->casez() || nodep->caseInside())) {
+				V3Number nummask (itemp->fileline(), iconstp->width());
+				nummask.opBitsNonX(iconstp->num());
+				V3Number numval  (itemp->fileline(), iconstp->width());
+				numval.opBitsOne(iconstp->num());
+				AstNode* and1p = new AstAnd(itemp->fileline(), nodep->exprp()->cloneTree(false),
+							    new AstConst(itemp->fileline(), nummask));
+				AstNode* and2p = new AstAnd(itemp->fileline(),
+							    new AstConst(itemp->fileline(), numval),
+							    new AstConst(itemp->fileline(), nummask));
+				onep = AstEq::newTyped(itemp->fileline(), and1p, and2p);
+
+			    } else {
+				onep = AstEq::newTyped(icondp->fileline(),
+						       nodep->exprp()->cloneTree(false),
+						       icondp->cloneTree(false));
+			    }
 			    if (propp) propp = new AstConcat(icondp->fileline(), onep, propp);
 			    else propp = onep;
 			}
 		    }
 		    bool allow_none = has_default || nodep->unique0Pragma();
 		    AstNode* ohot = (allow_none
-				     ? (new AstOneHot0(nodep->fileline(), propp))->castNode()
-				     : (new AstOneHot (nodep->fileline(), propp))->castNode());
+				     ? static_cast<AstNode*>(new AstOneHot0(nodep->fileline(), propp))
+				     : static_cast<AstNode*>(new AstOneHot (nodep->fileline(), propp)));
 		    AstIf* ifp = new AstIf (nodep->fileline(),
 					    new AstLogNot (nodep->fileline(), ohot),
 					    newFireAssert(nodep, "synthesis parallel_case, but multiple matches found"),
@@ -268,7 +285,7 @@ private:
    }

    // VISITORS  //========== Statements
-    virtual void visit(AstDisplay* nodep, AstNUser*) {
+    virtual void visit(AstDisplay* nodep) {
 	nodep->iterateChildren(*this);
 	// Replace the special types with standard text
 	if (nodep->displayType()==AstDisplayType::DT_INFO) {
@@ -281,27 +298,27 @@ private:
 	}
    }

-    virtual void visit(AstPslCover* nodep, AstNUser*) {
+    virtual void visit(AstPslCover* nodep) {
 	nodep->iterateChildren(*this);
 	if (m_beginp && nodep->name() == "") nodep->name(m_beginp->name());
 	newPslAssertion(nodep, nodep->propp(), nodep->sentreep(),
-			nodep->stmtsp(), nodep->name()); nodep=NULL;
+			nodep->stmtsp(), nodep->name()); VL_DANGLING(nodep);
 	++m_statAsCover;
    }
-    virtual void visit(AstVAssert* nodep, AstNUser*) {
+    virtual void visit(AstVAssert* nodep) {
 	nodep->iterateChildren(*this);
-	newVAssertion(nodep, nodep->propp()); nodep=NULL;
+	newVAssertion(nodep, nodep->propp()); VL_DANGLING(nodep);
 	++m_statAsSV;
    }

-    virtual void visit(AstNodeModule* nodep, AstNUser*) {
+    virtual void visit(AstNodeModule* nodep) {
 	m_modp = nodep;
 	//
 	nodep->iterateChildren(*this);
 	// Reset defaults
 	m_modp = NULL;
    }
-    virtual void visit(AstBegin* nodep, AstNUser*) {
+    virtual void visit(AstBegin* nodep) {
 	// This code is needed rather than a visitor in V3Begin,
 	// because V3Assert is called before V3Begin
 	AstBegin* lastp = m_beginp;
@@ -312,12 +329,12 @@ private:
 	m_beginp = lastp;
    }

-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }
 public:
    // CONSTRUCTORS
-    AssertVisitor(AstNetlist* nodep) {
+    explicit AssertVisitor(AstNetlist* nodep) {
 	m_beginp = NULL;
 	m_modp = NULL;
 	// Process
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2005-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2005-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2005-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2005-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -73,7 +73,7 @@ private:
    }

    // VISITORS  //========== Statements
-    virtual void visit(AstClocking* nodep, AstNUser*) {
+    virtual void visit(AstClocking* nodep) {
 	UINFO(8,"   CLOCKING"<<nodep<<endl);
 	// Store the new default clock, reset on new module
 	m_seniDefaultp = nodep->sensesp();
@@ -83,17 +83,17 @@ private:
 	} else {
 	    nodep->unlinkFrBack();
 	}
-	pushDeletep(nodep); nodep=NULL;
+	pushDeletep(nodep); VL_DANGLING(nodep);
    }

-    virtual void visit(AstPslCover* nodep, AstNUser*) {
+    virtual void visit(AstPslCover* nodep) {
 	if (nodep->sentreep()) return;  // Already processed
 	clearAssertInfo();
 	nodep->iterateChildren(*this);
 	nodep->sentreep(newSenTree(nodep));
 	clearAssertInfo();
    }
-    virtual void visit(AstPslClocked* nodep, AstNUser*) {
+    virtual void visit(AstPslClocked* nodep) {
 	nodep->iterateChildren(*this);
 	if (m_senip) {
 	    nodep->v3error("Unsupported: Only one PSL clock allowed per assertion");
@@ -109,20 +109,20 @@ private:
 	// Unlink and just keep a pointer to it, convert to sentree as needed
 	m_senip = nodep->sensesp();
 	nodep->replaceWith(blockp);
-	pushDeletep(nodep); nodep=NULL;
+	pushDeletep(nodep); VL_DANGLING(nodep);
    }
-    virtual void visit(AstNodeModule* nodep, AstNUser*) {
+    virtual void visit(AstNodeModule* nodep) {
 	nodep->iterateChildren(*this);
 	// Reset defaults
 	m_seniDefaultp = NULL;
    }
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }

 public:
    // CONSTRUCTORS
-    AssertPreVisitor(AstNetlist* nodep) {
+    explicit AssertPreVisitor(AstNetlist* nodep) {
 	m_seniDefaultp = NULL;
 	clearAssertInfo();
 	// Process
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2005-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2005-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -28,6 +28,7 @@
 #include "V3File.h"
 #include "V3Global.h"
 #include "V3Broken.h"
+#include "V3String.h"

 //======================================================================
 // Statics
@@ -79,30 +80,30 @@ void AstNode::init() {
    // Attributes
    m_didWidth = false;
    m_doingWidth = false;
-    m_user1p = NULL;
+    m_user1u = VNUser(0);
    m_user1Cnt = 0;
-    m_user2p = NULL;
+    m_user2u = VNUser(0);
    m_user2Cnt = 0;
-    m_user3p = NULL;
+    m_user3u = VNUser(0);
    m_user3Cnt = 0;
-    m_user4p = NULL;
+    m_user4u = VNUser(0);
    m_user4Cnt = 0;
-    m_user5p = NULL;
+    m_user5u = VNUser(0);
    m_user5Cnt = 0;
 }

 string AstNode::encodeName(const string& namein) {
    // Encode signal name raw from parser, then not called again on same signal
-    const char* start = namein.c_str();
    string out;
-    for (const char* pos = start; *pos; pos++) {
-	if ((pos==start) ? isalpha(pos[0])  // digits can't lead identifiers
+    for (string::const_iterator pos = namein.begin(); pos!=namein.end(); ++pos) {
+	if ((pos==namein.begin()) ? isalpha(pos[0])  // digits can't lead identifiers
 	    : isalnum(pos[0])) {
 	    out += pos[0];
 	} else if (pos[0]=='_') {
 	    if (pos[1]=='_') {
 		out += "_"; out += "__05F";  // hex(_) = 0x5F
-		pos++;
+		++pos;
+		if (pos==namein.end()) break;
 	    } else {
 		out += pos[0];
 	    }
@@ -115,6 +116,10 @@ string AstNode::encodeName(const string& namein) {
 	    out += hex;
 	}
    }
+    // Shorten names
+    // TODO long term use VName in place of "string name"
+    VName vname(out);
+    out = vname.hashedName();
    return out;
 }

@@ -161,44 +166,53 @@ string AstNode::vcdName(const string& namein) {
 }

 string AstNode::prettyName(const string& namein) {
+    // This function is somewhat hot, so we short-circuit some compares
    string pretty;
    pretty = "";
+    pretty.reserve(namein.length());
    for (const char* pos = namein.c_str(); *pos; ) {
-	if (0==strncmp(pos,"__BRA__",7)) {
-	    pretty += "[";
-	    pos += 7;
-	}
-	else if (0==strncmp(pos,"__KET__",7)) {
-	    pretty += "]";
-	    pos += 7;
-	}
-	else if (0==strncmp(pos,"__DOT__",7)) {
-	    pretty += ".";
-	    pos += 7;
-	}
-	else if (0==strncmp(pos,"->",2)) {
+	if (pos[0]=='-' && pos[1]=='>') { // ->
 	    pretty += ".";
 	    pos += 2;
+	    continue;
 	}
-	else if (0==strncmp(pos,"__PVT__",7)) {
-	    pretty += "";
-	    pos += 7;
-	}
-	else if (pos[0]=='_' && pos[1]=='_' && pos[2]=='0'
-		 && isxdigit(pos[3]) && isxdigit(pos[4])) {
-	    char value = 0;
-	    value += 16*(isdigit(pos[3]) ? (pos[3]-'0') : (tolower(pos[3])-'a'+10));
-	    value +=    (isdigit(pos[4]) ? (pos[4]-'0') : (tolower(pos[4])-'a'+10));
-	    pretty += value;
-	    pos += 5;
-	}
-	else {
-	    pretty += pos[0];
-	    pos++;
+	if (pos[0]=='_' && pos[1]=='_') { // Short-circuit
+	    if (0==strncmp(pos,"__BRA__",7)) {
+		pretty += "[";
+		pos += 7;
+		continue;
+	    }
+	    if (0==strncmp(pos,"__KET__",7)) {
+		pretty += "]";
+		pos += 7;
+		continue;
+	    }
+	    if (0==strncmp(pos,"__DOT__",7)) {
+		pretty += ".";
+		pos += 7;
+		continue;
+	    }
+	    if (0==strncmp(pos,"__PVT__",7)) {
+		pretty += "";
+		pos += 7;
+		continue;
+	    }
+	    if (pos[0]=='_' && pos[1]=='_' && pos[2]=='0'
+		     && isxdigit(pos[3]) && isxdigit(pos[4])) {
+		char value = 0;
+		value += 16*(isdigit(pos[3]) ? (pos[3]-'0') : (tolower(pos[3])-'a'+10));
+		value +=    (isdigit(pos[4]) ? (pos[4]-'0') : (tolower(pos[4])-'a'+10));
+		pretty += value;
+		pos += 5;
+		continue;
+	    }
 	}
+	// Default
+	pretty += pos[0];
+	++pos;
    }
-    if (pretty.substr(0,4) == "TOP.") pretty.replace(0,4,"");
-    if (pretty.substr(0,5) == "TOP->") pretty.replace(0,5,"");
+    if (pretty[0]=='T' && pretty.substr(0,4) == "TOP.") pretty.replace(0,4,"");
+    if (pretty[0]=='T' && pretty.substr(0,5) == "TOP->") pretty.replace(0,5,"");
    return pretty;
 }

@@ -230,20 +244,20 @@ inline void AstNode::debugTreeChange(const char* prefix, int lineno, bool next)
 #endif
 }

-AstNode* AstNode::addNext(AstNode* newp) {
+AstNode* AstNode::addNext(AstNode* nodep, AstNode* newp) {
    // Add to m_nextp, returns this
-    UASSERT(newp,"Null item passed to addNext\n");
-    this->debugTreeChange("-addNextThs: ", __LINE__, false);
+    UDEBUGONLY(if (!newp) nodep->v3fatalSrc("Null item passed to addNext"););
+    nodep->debugTreeChange("-addNextThs: ", __LINE__, false);
    newp->debugTreeChange("-addNextNew: ", __LINE__, true);
-    if (this == NULL) {
+    if (!nodep) {  // verilog.y and lots of other places assume this
 	return (newp);
    } else {
 	// Find end of old list
-	AstNode* oldtailp = this;
+	AstNode* oldtailp = nodep;
 	if (oldtailp->m_nextp) {
 	    if (oldtailp->m_headtailp) {
 		oldtailp = oldtailp->m_headtailp;  // This=beginning of list, jump to end
-		UASSERT(!oldtailp->m_nextp, "Node had next, but headtail says it shouldn't");
+		UDEBUGONLY(if (oldtailp->m_nextp) nodep->v3fatalSrc("Node had next, but headtail says it shouldn't"););
 	    } else {
 		// Though inefficent, we are occasionally passed a addNext in the middle of a list.
 		while (oldtailp->m_nextp != NULL) oldtailp = oldtailp->m_nextp;
@@ -262,21 +276,21 @@ AstNode* AstNode::addNext(AstNode* newp) {
 	newp->editCountInc();
 	if (oldtailp->m_iterpp) *(oldtailp->m_iterpp) = newp;	// Iterate on new item
    }
-    this->debugTreeChange("-addNextOut:", __LINE__, true);
-    return this;
+    nodep->debugTreeChange("-addNextOut:", __LINE__, true);
+    return nodep;
 }

-AstNode* AstNode::addNextNull(AstNode* newp) {
-    if (!newp) return this;
-    return addNext(newp);
+AstNode* AstNode::addNextNull(AstNode* nodep, AstNode* newp) {
+    if (!newp) return nodep;
+    return addNext(nodep, newp);
 }

 void AstNode::addNextHere(AstNode* newp) {
    // Add to m_nextp on exact node passed, not at the end.
    //  This could be at head, tail, or both (single)
    //  New  could be head of single node, or list
+    UDEBUGONLY(UASSERT(dynamic_cast<AstNode*>(this),"this should not be NULL"););
    UASSERT(newp,"Null item passed to addNext");
-    UASSERT(this,"Null base node");
    UASSERT(newp->backp()==NULL,"New node (back) already assigned?");
    this->debugTreeChange("-addHereThs: ", __LINE__, false);
    newp->debugTreeChange("-addHereNew: ", __LINE__, true);
@@ -600,12 +614,12 @@ void AstNode::swapWith (AstNode* bp) {
 // Clone

 AstNode* AstNode::cloneTreeIter() {
-    if (!this) return NULL;
+    // private: Clone single node and children
    AstNode* newp = this->clone();
-    newp->op1p(this->m_op1p->cloneTreeIterList());
-    newp->op2p(this->m_op2p->cloneTreeIterList());
-    newp->op3p(this->m_op3p->cloneTreeIterList());
-    newp->op4p(this->m_op4p->cloneTreeIterList());
+    if (this->m_op1p) newp->op1p(this->m_op1p->cloneTreeIterList());
+    if (this->m_op2p) newp->op2p(this->m_op2p->cloneTreeIterList());
+    if (this->m_op3p) newp->op3p(this->m_op3p->cloneTreeIterList());
+    if (this->m_op4p) newp->op4p(this->m_op4p->cloneTreeIterList());
    newp->m_iterpp = NULL;
    newp->clonep(this);		// Save pointers to/from both to simplify relinking.
    this->clonep(newp);		// Save pointers to/from both to simplify relinking.
@@ -613,10 +627,10 @@ AstNode* AstNode::cloneTreeIter() {
 }

 AstNode* AstNode::cloneTreeIterList() {
-    // Clone list of nodes, set m_headtailp
-    if (!this) return NULL;
+    // private: Clone list of nodes, set m_headtailp
    AstNode* newheadp = NULL;
    AstNode* newtailp = NULL;
+    // Audited to make sure this is never NULL
    for (AstNode* oldp = this; oldp; oldp=oldp->m_nextp) {
 	AstNode* newp = oldp->cloneTreeIter();
 	newp->m_headtailp = NULL;
@@ -631,7 +645,7 @@ AstNode* AstNode::cloneTreeIterList() {
 }

 AstNode* AstNode::cloneTree(bool cloneNextLink) {
-    if (!this) return NULL;
+    if (!this) return NULL;  // verilog.y relies on this
    this->debugTreeChange("-cloneThs: ", __LINE__, cloneNextLink);
    cloneClearTree();
    AstNode* newp;
@@ -652,7 +666,7 @@ AstNode* AstNode::cloneTree(bool cloneNextLink) {
 // Delete

 void AstNode::deleteNode() {
-    if (!this) return;
+    // private: Delete single node. Publicly call deleteTree() instead.
    UASSERT(m_backp==NULL,"Delete called on node with backlink still set\n");
    editCountInc();
    // Change links of old node so we coredump if used
@@ -672,14 +686,15 @@ AstNode::~AstNode() {
 }

 void AstNode::deleteTreeIter() {
-    if (!this) return;
+    // private: Delete list of nodes. Publicly call deleteTree() instead.
+    // Audited to make sure this is never NULL
    for (AstNode* nodep=this, *nnextp; nodep; nodep=nnextp) {
 	nnextp = nodep->m_nextp;
 	// MUST be depth first!
-	nodep->m_op1p->deleteTreeIter();
-	nodep->m_op2p->deleteTreeIter();
-	nodep->m_op3p->deleteTreeIter();
-	nodep->m_op4p->deleteTreeIter();
+	if (nodep->m_op1p) nodep->m_op1p->deleteTreeIter();
+	if (nodep->m_op2p) nodep->m_op2p->deleteTreeIter();
+	if (nodep->m_op3p) nodep->m_op3p->deleteTreeIter();
+	if (nodep->m_op4p) nodep->m_op4p->deleteTreeIter();
 	nodep->m_nextp = NULL;
 	nodep->m_backp = NULL;
 	nodep->deleteNode();
@@ -689,7 +704,6 @@ void AstNode::deleteTreeIter() {
 void AstNode::deleteTree() {
    // deleteTree always deletes the next link, because you must have called
    // unlinkFromBack or unlinkFromBackWithNext as appropriate before calling this.
-    if (!this) return;
    UASSERT(m_backp==NULL,"Delete called on node with backlink still set\n");
    this->debugTreeChange("-delTree:  ", __LINE__, true);
    this->editCountInc();
@@ -718,53 +732,48 @@ void AstNode::operator delete(void* objp, size_t size) {
 //======================================================================
 // Iterators

-void AstNode::iterateChildren(AstNVisitor& v, AstNUser* vup) {
+void AstNode::iterateChildren(AstNVisitor& v) {
    // This is a very hot function
-    if (!this) return;
    ASTNODE_PREFETCH(m_op1p);
    ASTNODE_PREFETCH(m_op2p);
    ASTNODE_PREFETCH(m_op3p);
    ASTNODE_PREFETCH(m_op4p);
-    // if () not needed since iterateAndNext accepts null this, but faster with it.
-    if (m_op1p) m_op1p->iterateAndNext(v, vup);
-    if (m_op2p) m_op2p->iterateAndNext(v, vup);
-    if (m_op3p) m_op3p->iterateAndNext(v, vup);
-    if (m_op4p) m_op4p->iterateAndNext(v, vup);
+    if (m_op1p) m_op1p->iterateAndNext(v);
+    if (m_op2p) m_op2p->iterateAndNext(v);
+    if (m_op3p) m_op3p->iterateAndNext(v);
+    if (m_op4p) m_op4p->iterateAndNext(v);
 }

-void AstNode::iterateChildrenConst(AstNVisitor& v, AstNUser* vup) {
+void AstNode::iterateChildrenConst(AstNVisitor& v) {
    // This is a very hot function
-    if (!this) return;
    ASTNODE_PREFETCH(m_op1p);
    ASTNODE_PREFETCH(m_op2p);
    ASTNODE_PREFETCH(m_op3p);
    ASTNODE_PREFETCH(m_op4p);
-    // if () not needed since iterateAndNext accepts null this, but faster with it.
-    if (m_op1p) m_op1p->iterateAndNextConst(v, vup);
-    if (m_op2p) m_op2p->iterateAndNextConst(v, vup);
-    if (m_op3p) m_op3p->iterateAndNextConst(v, vup);
-    if (m_op4p) m_op4p->iterateAndNextConst(v, vup);
+    if (m_op1p) m_op1p->iterateAndNextConst(v);
+    if (m_op2p) m_op2p->iterateAndNextConst(v);
+    if (m_op3p) m_op3p->iterateAndNextConst(v);
+    if (m_op4p) m_op4p->iterateAndNextConst(v);
 }

-void AstNode::iterateAndNext(AstNVisitor& v, AstNUser* vup) {
+void AstNode::iterateAndNext(AstNVisitor& v) {
    // This is a very hot function
    // IMPORTANT: If you replace a node that's the target of this iterator,
    // then the NEW node will be iterated on next, it isn't skipped!
-    // if (!this) return;  // Part of for()
    // Future versions of this function may require the node to have a back to be iterated;
    // there's no lower level reason yet though the back must exist.
    AstNode* nodep=this;
 #ifdef VL_DEBUG  // Otherwise too hot of a function for debug
    if (VL_UNLIKELY(nodep && !nodep->m_backp)) nodep->v3fatalSrc("iterateAndNext node has no back");
 #endif
-    while (nodep) {
+    while (nodep) {   // effectively: if (!this) return;  // Callers rely on this
 	AstNode* niterp = nodep;  // This address may get stomped via m_iterpp if the node is edited
 	ASTNODE_PREFETCH(nodep->m_nextp);
 	// Desirable check, but many places where multiple iterations are OK
 	//if (VL_UNLIKELY(niterp->m_iterpp)) niterp->v3fatalSrc("IterateAndNext under iterateAndNext may miss edits");
 	// cppcheck-suppress nullPointer
 	niterp->m_iterpp = &niterp;
-	niterp->accept(v, vup);
+	niterp->accept(v);
 	// accept may do a replaceNode and change niterp on us...
 	//if (niterp != nodep) UINFO(1,"iterateAndNext edited "<<(void*)nodep<<" now into "<<(void*)niterp<<endl);  // niterp maybe NULL, so need cast
 	if (!niterp) return;  // Perhaps node deleted inside accept
@@ -777,38 +786,37 @@ void AstNode::iterateAndNext(AstNVisitor& v, AstNUser* vup) {
    }
 }

-void AstNode::iterateListBackwards(AstNVisitor& v, AstNUser* vup) {
-    if (!this) return;
+void AstNode::iterateListBackwards(AstNVisitor& v) {
+    UDEBUGONLY(UASSERT(dynamic_cast<AstNode*>(this),"this should not be NULL"););
    AstNode* nodep=this;
    while (nodep->m_nextp) nodep=nodep->m_nextp;
    while (nodep) {
 	// Edits not supported: nodep->m_iterpp = &nodep;
-	nodep->accept(v, vup);
+	nodep->accept(v);
 	if (nodep->backp()->m_nextp == nodep) nodep=nodep->backp();
 	else nodep = NULL;  // else: backp points up the tree.
    }
 }

-void AstNode::iterateChildrenBackwards(AstNVisitor& v, AstNUser* vup) {
-    if (!this) return;
-    this->op1p()->iterateListBackwards(v,vup);
-    this->op2p()->iterateListBackwards(v,vup);
-    this->op3p()->iterateListBackwards(v,vup);
-    this->op4p()->iterateListBackwards(v,vup);
+void AstNode::iterateChildrenBackwards(AstNVisitor& v) {
+    if (m_op1p) m_op1p->iterateListBackwards(v);
+    if (m_op2p) m_op2p->iterateListBackwards(v);
+    if (m_op3p) m_op3p->iterateListBackwards(v);
+    if (m_op4p) m_op4p->iterateListBackwards(v);
 }

-void AstNode::iterateAndNextConst(AstNVisitor& v, AstNUser* vup) {
+void AstNode::iterateAndNextConst(AstNVisitor& v) {
    // Keep following the current list even if edits change it
-    if (!this) return;
-    for (AstNode* nodep=this; nodep; ) {
+    if (!this) return;  // A few cases could be cleaned up, but want symmetry with iterateAndNext
+    for (AstNode* nodep=this; nodep; ) {   // effectively: if (!this) return;  // Callers rely on this
 	AstNode* nnextp = nodep->m_nextp;
 	ASTNODE_PREFETCH(nnextp);
-	nodep->accept(v, vup);
+	nodep->accept(v);
 	nodep = nnextp;
    }
 }

-AstNode* AstNode::acceptSubtreeReturnEdits(AstNVisitor& v, AstNUser* vup) {
+AstNode* AstNode::iterateSubtreeReturnEdits(AstNVisitor& v) {
    // Some visitors perform tree edits (such as V3Const), and may even
    // replace/delete the exact nodep that the visitor is called with.  If
    // this happens, the parent will lose the handle to the node that was
@@ -818,15 +826,15 @@ AstNode* AstNode::acceptSubtreeReturnEdits(AstNVisitor& v, AstNUser* vup) {
    AstNode* nodep = this;  // Note "this" may point to bogus point later in this function
    if (nodep->castNetlist()) {
 	// Calling on top level; we know the netlist won't get replaced
-	nodep->accept(v, vup);
+	nodep->accept(v);
    } else if (!nodep->backp()) {
 	// Calling on standalone tree; insert a shim node so we can keep track, then delete it on completion
 	AstBegin* tempp = new AstBegin(nodep->fileline(),"[EditWrapper]",nodep);
 	{
-	    tempp->stmtsp()->accept(v, vup);  nodep=NULL; // nodep to null as may be replaced
+	    tempp->stmtsp()->accept(v); VL_DANGLING(nodep); // nodep to null as may be replaced
 	}
 	nodep = tempp->stmtsp()->unlinkFrBackWithNext();
-	tempp->deleteTree(); tempp=NULL;
+	tempp->deleteTree(); VL_DANGLING(tempp);
    } else {
 	// Use back to determine who's pointing at us (IE assume new node grafts into same place as old one)
 	AstNode** nextnodepp = NULL;
@@ -837,7 +845,7 @@ AstNode* AstNode::acceptSubtreeReturnEdits(AstNVisitor& v, AstNUser* vup) {
 	else if (this->m_backp->m_nextp == this) nextnodepp = &(this->m_backp->m_nextp);
 	if (!nextnodepp) this->v3fatalSrc("Node's back doesn't point to forward to node itself");
 	{
-	    nodep->accept(v, vup); nodep=NULL; // nodep to null as may be replaced
+	    nodep->accept(v); VL_DANGLING(nodep); // nodep to null as may be replaced
 	}
 	nodep = *nextnodepp;  // Grab new node from point where old was connected
    }
@@ -847,37 +855,47 @@ AstNode* AstNode::acceptSubtreeReturnEdits(AstNVisitor& v, AstNUser* vup) {
 //======================================================================

 void AstNode::cloneRelinkTree() {
-    if (!this) return;
+    // private: Cleanup clone() operation on whole tree. Publicly call cloneTree() instead.
    for (AstNode* nodep=this; nodep; nodep=nodep->m_nextp) {
 	if (m_dtypep && m_dtypep->clonep()) {
-	    m_dtypep = m_dtypep->clonep()->castNodeDType();
+	    m_dtypep = m_dtypep->clonep();
 	}
 	nodep->cloneRelink();
-	nodep->m_op1p->cloneRelinkTree();
-	nodep->m_op2p->cloneRelinkTree();
-	nodep->m_op3p->cloneRelinkTree();
-	nodep->m_op4p->cloneRelinkTree();
+	if (nodep->m_op1p) nodep->m_op1p->cloneRelinkTree();
+	if (nodep->m_op2p) nodep->m_op2p->cloneRelinkTree();
+	if (nodep->m_op3p) nodep->m_op3p->cloneRelinkTree();
+	if (nodep->m_op4p) nodep->m_op4p->cloneRelinkTree();
    }
 }

 //======================================================================
 // Comparison

-bool AstNode::sameTreeIter(AstNode* node2p, bool ignNext, bool gateOnly) {
-    // Return true if the two trees are identical
-    if (this==NULL && node2p==NULL) return true;
-    if (this==NULL || node2p==NULL) return false;
-    if (this->type() != node2p->type()
-	|| this->dtypep() != node2p->dtypep()
-	|| !this->same(node2p)
-	|| (gateOnly && !this->isGateOptimizable())) {
+bool AstNode::gateTreeIter() {
+    // private: Return true if the two trees are identical
+    if (!isGateOptimizable()) return false;
+    if (m_op1p && !m_op1p->gateTreeIter()) return false;
+    if (m_op2p && !m_op2p->gateTreeIter()) return false;
+    if (m_op3p && !m_op3p->gateTreeIter()) return false;
+    if (m_op4p && !m_op4p->gateTreeIter()) return false;
+    return true;
+}
+
+bool AstNode::sameTreeIter(AstNode* node1p, AstNode* node2p, bool ignNext, bool gateOnly) {
+    // private: Return true if the two trees are identical
+    if (!node1p && !node2p) return true;
+    if (!node1p || !node2p) return false;
+    if (node1p->type() != node2p->type()
+	|| node1p->dtypep() != node2p->dtypep()
+	|| !node1p->same(node2p)
+	|| (gateOnly && !node1p->isGateOptimizable())) {
 	return false;
    }
-    return (this->op1p()->sameTreeIter(node2p->op1p(),false,gateOnly)
-	    && this->op2p()->sameTreeIter(node2p->op2p(),false,gateOnly)
-	    && this->op3p()->sameTreeIter(node2p->op3p(),false,gateOnly)
-	    && this->op4p()->sameTreeIter(node2p->op4p(),false,gateOnly)
-	    && (ignNext || this->nextp()->sameTreeIter(node2p->nextp(),false,gateOnly))
+    return (sameTreeIter(node1p->m_op1p, node2p->m_op1p,false,gateOnly)
+	    && sameTreeIter(node1p->m_op2p, node2p->m_op2p,false,gateOnly)
+	    && sameTreeIter(node1p->m_op3p, node2p->m_op3p,false,gateOnly)
+	    && sameTreeIter(node1p->m_op4p, node2p->m_op4p,false,gateOnly)
+	    && (ignNext || sameTreeIter(node1p->m_nextp, node2p->m_nextp,false,gateOnly))
 	);
 }

@@ -901,6 +919,7 @@ V3Hash::V3Hash(const string& name) {
 // Debugging

 void AstNode::checkTreeIter(AstNode* backp) {
+    // private: Check a tree and children
    if (backp != this->backp()) {
 	this->v3fatalSrc("Back node inconsistent");
    }
@@ -909,15 +928,15 @@ void AstNode::checkTreeIter(AstNode* backp) {
 	if (op1p()||op2p()||op3p()||op4p())
 	    this->v3fatalSrc("Terminal operation with non-terminals");
    }
-    if (op1p()) op1p()->checkTreeIterList(this);
-    if (op2p()) op2p()->checkTreeIterList(this);
-    if (op3p()) op3p()->checkTreeIterList(this);
-    if (op4p()) op4p()->checkTreeIterList(this);
+    if (m_op1p) m_op1p->checkTreeIterList(this);
+    if (m_op2p) m_op2p->checkTreeIterList(this);
+    if (m_op3p) m_op3p->checkTreeIterList(this);
+    if (m_op4p) m_op4p->checkTreeIterList(this);
 }

 void AstNode::checkTreeIterList(AstNode* backp) {
-    // Check a (possible) list of nodes, this is always the head of the list
-    if (!this) v3fatalSrc("Null nodep");
+    // private: Check a (possible) list of nodes, this is always the head of the list
+    // Audited to make sure this is never NULL
    AstNode* headp = this;
    AstNode* tailp = this;
    for (AstNode* nodep=headp; nodep; nodep=nodep->nextp()) {
@@ -931,7 +950,6 @@ void AstNode::checkTreeIterList(AstNode* backp) {
 }

 void AstNode::checkTree() {
-    if (!this) return;
    if (!debug()) return;
    if (this->backp()) {
 	// Linked tree- check only the passed node
@@ -942,17 +960,17 @@ void AstNode::checkTree() {
 }

 void AstNode::dumpGdb() {  // For GDB only
-    if (!this) { cout<<"This=NULL"<<endl; return; }
+    if (!dynamic_cast<const AstNode*>(this)) { cout<<"This=NULL"<<endl; return; }
    dumpGdbHeader();
    cout<<"  "; dump(cout); cout<<endl;
 }
 void AstNode::dumpGdbHeader() const {  // For GDB only
-    if (!this) { cout<<"This=NULL"<<endl; return; }
+    if (!dynamic_cast<const AstNode*>(this)) { cout<<"This=NULL"<<endl; return; }
    dumpPtrs(cout);
    cout<<"  Fileline = "<<fileline()<<endl;
 }
 void AstNode::dumpTreeGdb() {  // For GDB only
-    if (!this) { cout<<"This=NULL"<<endl; return; }
+    if (!dynamic_cast<const AstNode*>(this)) { cout<<"This=NULL"<<endl; return; }
    dumpGdbHeader();
    dumpTree(cout);
 }
@@ -992,7 +1010,6 @@ void AstNode::dumpPtrs(ostream& os) const {
 }

 void AstNode::dumpTree(ostream& os, const string& indent, int maxDepth) {
-    if (!this) return;
    os<<indent<<" "<<this<<endl;
    if (debug()>8) { os<<indent<<"     "; dumpPtrs(os); }
    if (maxDepth==1) {
@@ -1006,7 +1023,7 @@ void AstNode::dumpTree(ostream& os, const string& indent, int maxDepth) {
 }

 void AstNode::dumpTreeAndNext(ostream& os, const string& indent, int maxDepth) {
-    if (!this) return;
+    // Audited to make sure this is never NULL
    for (AstNode* nodep=this; nodep; nodep=nodep->nextp()) {
 	nodep->dumpTree(os, indent, maxDepth);
    }
@@ -1016,7 +1033,7 @@ void AstNode::dumpTreeFile(const string& filename, bool append, bool doDump) {
    if (doDump) {
 	{   // Write log & close
 	    UINFO(2,"Dumping "<<filename<<endl);
-	    const auto_ptr<ofstream> logsp (V3File::new_ofstream(filename, append));
+	    const VL_UNIQUE_PTR<ofstream> logsp (V3File::new_ofstream(filename, append));
 	    if (logsp->fail()) v3fatalSrc("Can't write "<<filename);
 	    *logsp<<"Verilator Tree Dump (format 0x3900) from <e"<<dec<<editCountLast()<<">";
 	    *logsp<<" to <e"<<dec<<editCountGbl()<<">"<<endl;
@@ -1041,7 +1058,13 @@ void AstNode::dumpTreeFile(const string& filename, bool append, bool doDump) {
 }

 void AstNode::v3errorEnd(ostringstream& str) const {
-    if (this && m_fileline) {
+    if (!dynamic_cast<const AstNode*>(this)) {
+	// No known cases cause this, but better than a core dump
+	if (debug()) UINFO(0, "-node: NULL. Please report this along with a --gdbbt backtrace as a Verilator bug.\n");
+	V3Error::v3errorEnd(str);
+    } else if (!m_fileline) {
+	V3Error::v3errorEnd(str);
+    } else {
 	ostringstream nsstr;
 	nsstr<<str.str();
 	if (debug()) {
@@ -1049,14 +1072,11 @@ void AstNode::v3errorEnd(ostringstream& str) const {
 	    nsstr<<"-node: "; ((AstNode*)this)->dump(nsstr); nsstr<<endl;
 	}
 	m_fileline->v3errorEnd(nsstr);
-    } else {
-	V3Error::v3errorEnd(str);
    }
 }

 string AstNode::warnMore() const {
-    if (this) return this->fileline()->warnMore();
-    else return V3Error::warnMore();
+    return fileline()->warnMore();
 }

 //======================================================================
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -53,6 +53,7 @@ public:
    enum en m_e;
    // cppcheck-suppress uninitVar  // responsiblity of each subclass
    inline AstType () {}
+    // cppcheck-suppress noExplicitConstructor
    inline AstType (en _e) : m_e(_e) {}
    explicit inline AstType (int _e) : m_e(static_cast<en>(_e)) {}
    operator en () const { return m_e; }
@@ -87,7 +88,9 @@ public:
 	return names[m_e];
    };
    inline AstNumeric () : m_e(UNSIGNED) {}
+    // cppcheck-suppress noExplicitConstructor
    inline AstNumeric (en _e) : m_e(_e) {}
+    // cppcheck-suppress noExplicitConstructor
    inline AstNumeric (VSignedState signst) {
 	if (signst==signedst_UNSIGNED) m_e=UNSIGNED;
 	else if (signst==signedst_SIGNED) m_e=SIGNED;
@@ -121,6 +124,7 @@ public:
    };
    enum en m_e;
    inline AstPragmaType () : m_e(ILLEGAL) {}
+    // cppcheck-suppress noExplicitConstructor
    inline AstPragmaType (en _e) : m_e(_e) {}
    explicit inline AstPragmaType (int _e) : m_e(static_cast<en>(_e)) {}
    operator en () const { return m_e; }
@@ -144,6 +148,7 @@ public:
    };
    enum en m_e;
    inline AstCFuncType () : m_e(FT_NORMAL) {}
+    // cppcheck-suppress noExplicitConstructor
    inline AstCFuncType (en _e) : m_e(_e) {}
    explicit inline AstCFuncType (int _e) : m_e(static_cast<en>(_e)) {}
    operator en () const { return m_e; }
@@ -212,6 +217,7 @@ public:
 	return names[m_e];
    };
    inline AstEdgeType () : m_e(ET_ILLEGAL) {}
+    // cppcheck-suppress noExplicitConstructor
    inline AstEdgeType (en _e) : m_e(_e) {}
    explicit inline AstEdgeType (int _e) : m_e(static_cast<en>(_e)) {}
    operator en () const { return m_e; }
@@ -239,6 +245,7 @@ public:
 	//
 	DT_PUBLIC,			// V3LinkParse moves to AstTypedef::attrPublic
 	//
+	ENUM_BASE,			// V3LinkResolve creates for AstPreSel, V3LinkParam removes
 	ENUM_FIRST,			// V3Width processes
 	ENUM_LAST,			// V3Width processes
 	ENUM_NUM,			// V3Width processes
@@ -268,7 +275,7 @@ public:
 	    "DIM_BITS", "DIM_DIMENSIONS", "DIM_HIGH", "DIM_INCREMENT", "DIM_LEFT",
 	    "DIM_LOW", "DIM_RIGHT", "DIM_SIZE", "DIM_UNPK_DIMENSIONS",
 	    "DT_PUBLIC",
-	    "ENUM_FIRST", "ENUM_LAST", "ENUM_NUM", "ENUM_NEXT", "ENUM_PREV", "ENUM_NAME",
+	    "ENUM_BASE", "ENUM_FIRST", "ENUM_LAST", "ENUM_NUM", "ENUM_NEXT", "ENUM_PREV", "ENUM_NAME",
 	    "MEMBER_BASE",
 	    "VAR_BASE", "VAR_CLOCK", "VAR_CLOCK_ENABLE", "VAR_PUBLIC",
 	    "VAR_PUBLIC_FLAT", "VAR_PUBLIC_FLAT_RD","VAR_PUBLIC_FLAT_RW",
@@ -278,6 +285,7 @@ public:
 	return names[m_e];
    };
    inline AstAttrType () : m_e(ILLEGAL) {}
+    // cppcheck-suppress noExplicitConstructor
    inline AstAttrType (en _e) : m_e(_e) {}
    explicit inline AstAttrType (int _e) : m_e(static_cast<en>(_e)) {}
    operator en () const { return m_e; }
@@ -337,6 +345,7 @@ public:
 	UASSERT(0==strcmp(AstBasicDTypeKwd(_ENUM_MAX).dpiType()," MAX"),"Enum array mismatch");
    }
    inline AstBasicDTypeKwd () : m_e(UNKNOWN) {}
+    // cppcheck-suppress noExplicitConstructor
    inline AstBasicDTypeKwd (en _e) : m_e(_e) {}
    explicit inline AstBasicDTypeKwd (int _e) : m_e(static_cast<en>(_e)) {}
    operator en () const { return m_e; }
@@ -418,6 +427,7 @@ public:
 	SUPPLY0,
 	SUPPLY1,
 	WIRE,
+	WREAL,
 	IMPLICITWIRE,
 	TRIWIRE,
 	TRI0,
@@ -431,6 +441,7 @@ public:
    };
    enum en m_e;
    inline AstVarType () : m_e(UNKNOWN) {}
+    // cppcheck-suppress noExplicitConstructor
    inline AstVarType (en _e) : m_e(_e) {}
    explicit inline AstVarType (int _e) : m_e(static_cast<en>(_e)) {}
    operator en () const { return m_e; }
@@ -438,13 +449,13 @@ public:
 	static const char* names[] = {
 	    "?","GPARAM","LPARAM","GENVAR",
 	    "VAR","INPUT","OUTPUT","INOUT",
-	    "SUPPLY0","SUPPLY1","WIRE","IMPLICITWIRE",
+	    "SUPPLY0","SUPPLY1","WIRE","WREAL","IMPLICITWIRE",
 	    "TRIWIRE","TRI0","TRI1",
 	    "PORT",
 	    "BLOCKTEMP","MODULETEMP","STMTTEMP","XTEMP",
 	    "IFACEREF"};
 	return names[m_e]; }
-    bool isSignal() const  { return (m_e==WIRE || m_e==IMPLICITWIRE
+    bool isSignal() const  { return (m_e==WIRE || m_e==WREAL || m_e==IMPLICITWIRE
 				     || m_e==TRIWIRE
 				     || m_e==TRI0 || m_e==TRI1
 				     || m_e==SUPPLY0 || m_e==SUPPLY1
@@ -468,6 +479,7 @@ public:
    enum en m_e;
    // CONSTRUCTOR - note defaults to *UNKNOWN*
    inline AstBranchPred () : m_e(BP_UNKNOWN) {}
+    // cppcheck-suppress noExplicitConstructor
    inline AstBranchPred (en _e) : m_e(_e) {}
    explicit inline AstBranchPred (int _e) : m_e(static_cast<en>(_e)) {}
    operator en () const { return m_e; }
@@ -499,9 +511,11 @@ public:
    enum en m_e;
    // CONSTRUCTOR - note defaults to *UNKNOWN*
    inline AstVarAttrClocker () : m_e(CLOCKER_UNKNOWN) {}
+    // cppcheck-suppress noExplicitConstructor
    inline AstVarAttrClocker (en _e) : m_e(_e) {}
    explicit inline AstVarAttrClocker (int _e) : m_e(static_cast<en>(_e)) {}
    operator en () const { return m_e; }
+    bool unknown() const { return m_e==CLOCKER_UNKNOWN; }
    AstVarAttrClocker invert() const {
 	if (m_e==CLOCKER_YES) return CLOCKER_NO;
 	else if (m_e==CLOCKER_NO) return CLOCKER_YES;
@@ -529,6 +543,7 @@ public:
    };
    enum en m_e;
    inline VAlwaysKwd () : m_e(ALWAYS) {}
+    // cppcheck-suppress noExplicitConstructor
    inline VAlwaysKwd (en _e) : m_e(_e) {}
    explicit inline VAlwaysKwd (int _e) : m_e(static_cast<en>(_e)) {}
    operator en () const { return m_e; }
@@ -553,6 +568,7 @@ public:
    };
    enum en m_e;
    inline VCaseType () : m_e(CT_CASE) {}
+    // cppcheck-suppress noExplicitConstructor
    inline VCaseType (en _e) : m_e(_e) {}
    explicit inline VCaseType (int _e) : m_e(static_cast<en>(_e)) {}
    operator en () const { return m_e; }
@@ -575,6 +591,7 @@ public:
    };
    enum en m_e;
    inline AstDisplayType () : m_e(DT_DISPLAY) {}
+    // cppcheck-suppress noExplicitConstructor
    inline AstDisplayType (en _e) : m_e(_e) {}
    explicit inline AstDisplayType (int _e) : m_e(static_cast<en>(_e)) {}
    operator en () const { return m_e; }
@@ -599,6 +616,7 @@ public:
    };
    enum en m_e;
    inline AstParseRefExp() : m_e(PX_NONE) {}
+    // cppcheck-suppress noExplicitConstructor
    inline AstParseRefExp (en _e) : m_e(_e) {}
    explicit inline AstParseRefExp (int _e) : m_e(static_cast<en>(_e)) {}
    operator en () const { return m_e; }
@@ -698,7 +716,7 @@ struct VBasicTypeKey {
 };

 //######################################################################
-// AstNUser - Generic pointer base class for AST User nodes.
+// AstNUser - Generic base class for AST User nodes.
 //	    - Also used to allow parameter passing up/down iterate calls

 class WidthVP;
@@ -707,26 +725,30 @@ class OrderBlockNU;
 class OrderVarNU;
 class V3GraphVertex;
 class VSymEnt;
-struct AstNUser {
-    AstNUser*	p() { return this; }	// So can take address of temporary: iterate(...,AstNUser(args).p())
+
+class VNUser {
+    union {
+	void* up;
+	int ui;
+    } m_u;
+public:
+    VNUser() {}
+    VNUser(int i) { m_u.up = 0; m_u.ui = i; }
+    VNUser(void* p) { m_u.up = p; }
+    ~VNUser() {}
    // Casters
-    WidthVP*	c() { return ((WidthVP*)this); }
-    LinkVP*	castLinkVP() { return ((LinkVP*)this); }
-    VSymEnt*	castSymEnt() { return ((VSymEnt*)this); }
-    AstNode*	castNode() { return ((AstNode*)this); }
-    OrderBlockNU* castOrderBlock() { return ((OrderBlockNU*)this); }
-    OrderVarNU*	castOrderVar() { return ((OrderVarNU*)this); }
-    V3GraphVertex* castGraphVertex() { return ((V3GraphVertex*)this); }
-    inline int	castInt() {
-	union { AstNUser* up; int ui; } u;
-	u.up = this;
-	return u.ui;
-    }
-    static inline AstNUser* fromInt (int i) {
-	union { AstNUser* up; int ui; } u;
-	u.up=0; u.ui=i;
-	return u.up;
+    WidthVP*	c() { return ((WidthVP*)m_u.up); }
+    LinkVP*	toLinkVP() { return ((LinkVP*)m_u.up); }
+    VSymEnt*	toSymEnt() { return ((VSymEnt*)m_u.up); }
+    AstNode*	toNodep() { return ((AstNode*)m_u.up); }
+    OrderBlockNU* toOrderBlock() { return ((OrderBlockNU*)m_u.up); }
+    OrderVarNU*	toOrderVar() { return ((OrderVarNU*)m_u.up); }
+    V3GraphVertex* toGraphVertex() { return ((V3GraphVertex*)m_u.up); }
+    inline int	toInt() {
+	return m_u.ui;
    }
+    static inline VNUser fromZero () { return VNUser(0); }
+    static inline VNUser fromInt (int i) { return VNUser(i); }
 };

 //######################################################################
@@ -845,7 +867,8 @@ public:
    }
 #include "V3Ast__gen_visitor.h"	// From ./astgen
    // Things like:
-    //  virtual void visit(type*) = 0;
+    //  virtual void visit(AstBreak* nodep) { visit((AstNodeStmt*)(nodep)); }
+    //  virtual void visit(AstNodeStmt* nodep) { visit((AstNode*)(nodep)); }
 };

 //######################################################################
@@ -896,16 +919,19 @@ public:
    // CREATORS
    class Illegal {};		// for creator type-overload selection
    class FullValue {};		// for creator type-overload selection
-    V3Hash(Illegal) { m_both=0; }
+    explicit V3Hash(Illegal) { m_both=0; }
    // Saving and restoring inside a userp
-    V3Hash(AstNUser* up) { m_both=up->castInt(); }
+    explicit V3Hash(VNUser u) { m_both=u.toInt(); }
    V3Hash operator+= (const V3Hash& rh) {
 	setBoth(depth()+rh.depth(), (hshval()*31+rh.hshval()));
 	return *this; };
    // Creating from raw data (sameHash functions)
    V3Hash() { setBoth(1,0); }
+    // cppcheck-suppress noExplicitConstructor
    V3Hash(uint32_t val) { setBoth(1,val); }
+    // cppcheck-suppress noExplicitConstructor
    V3Hash(const void* vp) { setBoth(1,cvtToHash(vp)); }
+    // cppcheck-suppress noExplicitConstructor
    V3Hash(const string& name);
    V3Hash(V3Hash h1, V3Hash h2) {
 	setBoth(1,h1.hshval()*31+h2.hshval()); }
@@ -954,15 +980,15 @@ class AstNode {
    //		// Space for more bools here

    // This member ordering both allows 64 bit alignment and puts associated data together
-    AstNUser*	m_user1p;	// Pointer to any information the user iteration routine wants
+    VNUser	m_user1u;	// Contains any information the user iteration routine wants
    uint32_t	m_user1Cnt;	// Mark of when userp was set
    uint32_t	m_user2Cnt;	// Mark of when userp was set
-    AstNUser*	m_user2p;	// Pointer to any information the user iteration routine wants
-    AstNUser*	m_user3p;	// Pointer to any information the user iteration routine wants
+    VNUser	m_user2u;	// Contains any information the user iteration routine wants
+    VNUser	m_user3u;	// Contains any information the user iteration routine wants
    uint32_t	m_user3Cnt;	// Mark of when userp was set
    uint32_t	m_user4Cnt;	// Mark of when userp was set
-    AstNUser*	m_user4p;	// Pointer to any information the user iteration routine wants
-    AstNUser*	m_user5p;	// Pointer to any information the user iteration routine wants
+    VNUser	m_user4u;	// Contains any information the user iteration routine wants
+    VNUser	m_user5u;	// Contains any information the user iteration routine wants
    uint32_t	m_user5Cnt;	// Mark of when userp was set

    // METHODS
@@ -972,14 +998,17 @@ class AstNode {
    void	op4p(AstNode* nodep) { m_op4p = nodep; if (nodep) nodep->m_backp = this; }

    void	init();	// initialize value of AstNode
-    void	iterateListBackwards(AstNVisitor& v, AstNUser* vup=NULL);
+    void	iterateListBackwards(AstNVisitor& v);
+private:
    AstNode*	cloneTreeIter();
    AstNode*	cloneTreeIterList();
    void	checkTreeIter(AstNode* backp);
    void	checkTreeIterList(AstNode* backp);
-    bool	sameTreeIter(AstNode* node2p, bool ignNext, bool gateOnly);
+    bool	gateTreeIter();
+    bool	sameTreeIter(AstNode* node1p, AstNode* node2p, bool ignNext, bool gateOnly);
    void	deleteTreeIter();
    void	deleteNode();
+public:
    static void	relinkOneLink(AstNode*& pointpr, AstNode* newp);
    // cppcheck-suppress functionConst
    void	debugTreeChange(const char* prefix, int lineno, bool next);
@@ -987,7 +1016,7 @@ class AstNode {
 protected:
    // CONSTUCTORS
    AstNode() {init(); }
-    AstNode(FileLine* fileline) {init(); m_fileline = fileline; }
+    explicit AstNode(FileLine* fileline) {init(); m_fileline = fileline; }
    virtual AstNode* clone() = 0;	// Generally, cloneTree is what you want instead
    virtual void cloneRelink() {}
    void 	cloneRelinkTree();
@@ -1087,57 +1116,75 @@ public:
    bool	isSigned() const;
    bool	isString() const;

-    AstNUser*	user1p() const {
+    VNUser	user1u() const {
 	// Slows things down measurably, so disabled by default
 	//UASSERT_STATIC(AstUser1InUse::s_userBusy, "userp set w/o busy");
-	return ((m_user1Cnt==AstUser1InUse::s_userCntGbl)?m_user1p:NULL);
+	return ((m_user1Cnt==AstUser1InUse::s_userCntGbl) ? m_user1u : VNUser(0));
    }
-    void	user1p(void* userp) { m_user1p=(AstNUser*)(userp); m_user1Cnt=AstUser1InUse::s_userCntGbl; }
-    int		user1() const { return user1p()->castInt(); }
-    void	user1(int val) { user1p(AstNUser::fromInt(val)); }
-    int		user1Inc() { int v=user1(); user1(v+1); return v; }
+    AstNode*	user1p() const { return user1u().toNodep(); }
+    void	user1u(const VNUser& user) { m_user1u=user; m_user1Cnt=AstUser1InUse::s_userCntGbl; }
+    void	user1p(void* userp) { user1u(VNUser(userp)); }
+    int		user1() const { return user1u().toInt(); }
+    void	user1(int val) { user1u(VNUser(val)); }
+    int		user1Inc(int val=1) { int v=user1(); user1(v+val); return v; }
    int		user1SetOnce() { int v=user1(); if (!v) user1(1); return v; } // Better for cache than user1Inc()
    static void	user1ClearTree() { AstUser1InUse::clear(); }  // Clear userp()'s across the entire tree

-    AstNUser*	user2p() const {
-	//UASSERT_STATIC(AstUser2InUse::s_userBusy, "user2p set w/o busy");
-	return ((m_user2Cnt==AstUser2InUse::s_userCntGbl)?m_user2p:NULL); }
-    void	user2p(void* userp) { m_user2p=(AstNUser*)(userp); m_user2Cnt=AstUser2InUse::s_userCntGbl; }
-    int		user2() const { return user2p()->castInt(); }
-    void	user2(int val) { user2p(AstNUser::fromInt(val)); }
-    int		user2Inc() { int v=user2(); user2(v+1); return v; }
-    int		user2SetOnce() { int v=user2(); if (!v) user2(1); return v; }
-    static void	user2ClearTree() { AstUser2InUse::clear(); }
+    VNUser	user2u() const {
+	// Slows things down measurably, so disabled by default
+	//UASSERT_STATIC(AstUser2InUse::s_userBusy, "userp set w/o busy");
+	return ((m_user2Cnt==AstUser2InUse::s_userCntGbl) ? m_user2u : VNUser(0));
+    }
+    AstNode*	user2p() const { return user2u().toNodep(); }
+    void	user2u(const VNUser& user) { m_user2u=user; m_user2Cnt=AstUser2InUse::s_userCntGbl; }
+    void	user2p(void* userp) { user2u(VNUser(userp)); }
+    int		user2() const { return user2u().toInt(); }
+    void	user2(int val) { user2u(VNUser(val)); }
+    int		user2Inc(int val=1) { int v=user2(); user2(v+val); return v; }
+    int		user2SetOnce() { int v=user2(); if (!v) user2(1); return v; } // Better for cache than user2Inc()
+    static void	user2ClearTree() { AstUser2InUse::clear(); }  // Clear userp()'s across the entire tree

-    AstNUser*	user3p() const {
-	//UASSERT_STATIC(AstUser3InUse::s_userBusy, "user3p set w/o busy");
-	return ((m_user3Cnt==AstUser3InUse::s_userCntGbl)?m_user3p:NULL); }
-    void	user3p(void* userp) { m_user3p=(AstNUser*)(userp); m_user3Cnt=AstUser3InUse::s_userCntGbl; }
-    int		user3() const { return user3p()->castInt(); }
-    void	user3(int val) { user3p(AstNUser::fromInt(val)); }
-    int		user3Inc() { int v=user3(); user3(v+1); return v; }
-    int		user3SetOnce() { int v=user3(); if (!v) user3(1); return v; }
-    static void	user3ClearTree() { AstUser3InUse::clear(); }
+    VNUser	user3u() const {
+	// Slows things down measurably, so disabled by default
+	//UASSERT_STATIC(AstUser3InUse::s_userBusy, "userp set w/o busy");
+	return ((m_user3Cnt==AstUser3InUse::s_userCntGbl) ? m_user3u : VNUser(0));
+    }
+    AstNode*	user3p() const { return user3u().toNodep(); }
+    void	user3u(const VNUser& user) { m_user3u=user; m_user3Cnt=AstUser3InUse::s_userCntGbl; }
+    void	user3p(void* userp) { user3u(VNUser(userp)); }
+    int		user3() const { return user3u().toInt(); }
+    void	user3(int val) { user3u(VNUser(val)); }
+    int		user3Inc(int val=1) { int v=user3(); user3(v+val); return v; }
+    int		user3SetOnce() { int v=user3(); if (!v) user3(1); return v; } // Better for cache than user3Inc()
+    static void	user3ClearTree() { AstUser3InUse::clear(); }  // Clear userp()'s across the entire tree

-    AstNUser*	user4p() const {
-	//UASSERT_STATIC(AstUser4InUse::s_userBusy, "user4p set w/o busy");
-	return ((m_user4Cnt==AstUser4InUse::s_userCntGbl)?m_user4p:NULL); }
-    void	user4p(void* userp) { m_user4p=(AstNUser*)(userp); m_user4Cnt=AstUser4InUse::s_userCntGbl; }
-    int		user4() const { return user4p()->castInt(); }
-    void	user4(int val) { user4p(AstNUser::fromInt(val)); }
-    int		user4Inc() { int v=user4(); user4(v+1); return v; }
-    int		user4SetOnce() { int v=user4(); if (!v) user4(1); return v; }
-    static void	user4ClearTree() { AstUser4InUse::clear(); }
+    VNUser	user4u() const {
+	// Slows things down measurably, so disabled by default
+	//UASSERT_STATIC(AstUser4InUse::s_userBusy, "userp set w/o busy");
+	return ((m_user4Cnt==AstUser4InUse::s_userCntGbl) ? m_user4u : VNUser(0));
+    }
+    AstNode*	user4p() const { return user4u().toNodep(); }
+    void	user4u(const VNUser& user) { m_user4u=user; m_user4Cnt=AstUser4InUse::s_userCntGbl; }
+    void	user4p(void* userp) { user4u(VNUser(userp)); }
+    int		user4() const { return user4u().toInt(); }
+    void	user4(int val) { user4u(VNUser(val)); }
+    int		user4Inc(int val=1) { int v=user4(); user4(v+val); return v; }
+    int		user4SetOnce() { int v=user4(); if (!v) user4(1); return v; } // Better for cache than user4Inc()
+    static void	user4ClearTree() { AstUser4InUse::clear(); }  // Clear userp()'s across the entire tree

-    AstNUser*	user5p() const {
-	//UASSERT_STATIC(AstUser5InUse::s_userBusy, "user5p set w/o busy");
-	return ((m_user5Cnt==AstUser5InUse::s_userCntGbl)?m_user5p:NULL); }
-    void	user5p(void* userp) { m_user5p=(AstNUser*)(userp); m_user5Cnt=AstUser5InUse::s_userCntGbl; }
-    int		user5() const { return user5p()->castInt(); }
-    void	user5(int val) { user5p(AstNUser::fromInt(val)); }
-    int		user5Inc() { int v=user5(); user5(v+1); return v; }
-    int		user5SetOnce() { int v=user5(); if (!v) user5(1); return v; }
-    static void	user5ClearTree() { AstUser5InUse::clear(); }
+    VNUser	user5u() const {
+	// Slows things down measurably, so disabled by default
+	//UASSERT_STATIC(AstUser5InUse::s_userBusy, "userp set w/o busy");
+	return ((m_user5Cnt==AstUser5InUse::s_userCntGbl) ? m_user5u : VNUser(0));
+    }
+    AstNode*	user5p() const { return user5u().toNodep(); }
+    void	user5u(const VNUser& user) { m_user5u=user; m_user5Cnt=AstUser5InUse::s_userCntGbl; }
+    void	user5p(void* userp) { user5u(VNUser(userp)); }
+    int		user5() const { return user5u().toInt(); }
+    void	user5(int val) { user5u(VNUser(val)); }
+    int		user5Inc(int val=1) { int v=user5(); user5(v+val); return v; }
+    int		user5SetOnce() { int v=user5(); if (!v) user5(1); return v; } // Better for cache than user5Inc()
+    static void	user5ClearTree() { AstUser5InUse::clear(); }  // Clear userp()'s across the entire tree

    vluint64_t	editCount() const { return m_editCount; }
    void	editCountInc() { m_editCount = ++s_editCntGbl; }  // Preincrement, so can "watch AstNode::s_editCntGbl=##"
@@ -1189,8 +1236,10 @@ public:
    void	dumpGdbHeader() const;

    // METHODS - Tree modifications
-    AstNode*	addNext(AstNode* newp);		// Returns this, adds to end of list
-    AstNode*	addNextNull(AstNode* newp);	// Returns this, adds to end of list, NULL is OK
+    static AstNode* addNext(AstNode* nodep, AstNode* newp);	// Returns nodep, adds newp to end of nodep's list
+    static AstNode* addNextNull(AstNode* nodep, AstNode* newp);	// Returns nodep, adds newp (maybe NULL) to end of nodep's list
+    inline AstNode* addNext(AstNode* newp) { return addNext(this, newp); }
+    inline AstNode* addNextNull(AstNode* newp) { return addNextNull(this, newp); }
    void	addNextHere(AstNode* newp);	// Adds after speced node
    void	addPrev(AstNode* newp) { replaceWith(newp); newp->addNext(this); }
    void	addHereThisAsNext(AstNode* newp); // Adds at old place of this, this becomes next
@@ -1206,6 +1255,7 @@ public:

    // METHODS - Iterate on a tree
    AstNode*	cloneTree(bool cloneNextLink);
+    bool	gateTree() { return gateTreeIter(); }  // Is tree gateOptimizable?
    bool	sameTree(AstNode* node2p);	// Does tree of this == node2p?
    bool	sameGateTree(AstNode* node2p);	// Does tree of this == node2p?, not allowing non-isGateOptimizable
    void	deleteTree();	// Always deletes the next link
@@ -1238,18 +1288,16 @@ public:
    virtual const char* broken() const { return NULL; }

    // INVOKERS
-    virtual void accept(AstNVisitor& v, AstNUser* vup=NULL) = 0;
-    void	iterate(AstNVisitor& v, AstNUser* vup=NULL) { this->accept(v,vup); } 	  // Does this; excludes following this->next
-    void	iterateAndNext(AstNVisitor& v, AstNUser* vup=NULL);
-    void	iterateAndNextConst(AstNVisitor& v, AstNUser* vup=NULL);
-    void	iterateAndNextIgnoreEdit(AstNVisitor& v, AstNUser* vup=NULL) { iterateAndNextConst(v, vup); }
-    void	iterateChildren(AstNVisitor& v, AstNUser* vup=NULL);  // Excludes following this->next
-    void	iterateChildrenBackwards(AstNVisitor& v, AstNUser* vup=NULL);  // Excludes following this->next
-    void	iterateChildrenConst(AstNVisitor& v, AstNUser* vup=NULL);  // Excludes following this->next
-    AstNode*	acceptSubtreeReturnEdits(AstNVisitor& v, AstNUser* vup=NULL);  // Return edited nodep; see comments in V3Ast.cpp
+    virtual void accept(AstNVisitor& v) = 0;
+    void	iterate(AstNVisitor& v) { this->accept(v); } 	  // Does this; excludes following this->next
+    void	iterateAndNext(AstNVisitor& v);
+    void	iterateAndNextConst(AstNVisitor& v);
+    void	iterateChildren(AstNVisitor& v);  // Excludes following this->next
+    void	iterateChildrenBackwards(AstNVisitor& v);  // Excludes following this->next
+    void	iterateChildrenConst(AstNVisitor& v);  // Excludes following this->next
+    AstNode*	iterateSubtreeReturnEdits(AstNVisitor& v);  // Return edited nodep; see comments in V3Ast.cpp

    // CONVERSION
-    AstNode*	castNode() { return this; }
 #include "V3Ast__gen_interface.h"	// From ./astgen
    // Things like:
    //  AstAlways*	castAlways();
@@ -1264,12 +1312,13 @@ inline void AstNRelinker::relink(AstNode* newp) { newp->AstNode::relink(this); }

 #define ASTNODE_BASE_FUNCS(name)	\
    virtual ~Ast ##name() {} \
-    Ast ##name * cloneTree(bool cloneNext) { return AstNode::cloneTree(cloneNext)->cast ##name(); }
+    Ast ##name * cloneTree(bool cloneNext) { return static_cast<Ast ##name *>(AstNode::cloneTree(cloneNext)); } \
+    Ast ##name * clonep() const { return static_cast<Ast ##name *>(AstNode::clonep()); }

 class AstNodeMath : public AstNode {
    // Math -- anything that's part of an expression tree
 public:
-    AstNodeMath(FileLine* fl)
+    explicit AstNodeMath(FileLine* fl)
 	: AstNode(fl) {}
    ASTNODE_BASE_FUNCS(NodeMath)
    // METHODS
@@ -1286,13 +1335,13 @@ public:
 class AstNodeTermop : public AstNodeMath {
    // Terminal operator -- a operator with no "inputs"
 public:
-    AstNodeTermop(FileLine* fl)
+    explicit AstNodeTermop(FileLine* fl)
 	: AstNodeMath(fl) {}
    ASTNODE_BASE_FUNCS(NodeTermop)
    // Know no children, and hot function, so skip iterator for speed
    // See checkTreeIter also that asserts no children
    // cppcheck-suppress functionConst
-    void iterateChildren(AstNVisitor& v, AstNUser* vup=NULL) { }
+    void iterateChildren(AstNVisitor& v) { }
 };

 class AstNodeUniop : public AstNodeMath {
@@ -1303,7 +1352,7 @@ public:
 	dtypeFrom(lhsp);
 	setOp1p(lhsp); }
    ASTNODE_BASE_FUNCS(NodeUniop)
-    AstNode*	lhsp() 	const { return op1p()->castNode(); }
+    AstNode*	lhsp() 	const { return op1p(); }
    void	lhsp(AstNode* nodep)  { return setOp1p(nodep); }
    // METHODS
    virtual void numberOperate(V3Number& out, const V3Number& lhs) = 0; // Set out to evaluation of a AstConst'ed lhs
@@ -1324,8 +1373,10 @@ public:
 	: AstNodeMath(fl) {
 	setOp1p(lhs); setOp2p(rhs); }
    ASTNODE_BASE_FUNCS(NodeBiop)
-    AstNode*	lhsp() 	const { return op1p()->castNode(); }
-    AstNode*	rhsp() 	const { return op2p()->castNode(); }
+    virtual AstNode* cloneType(AstNode* lhsp, AstNode* rhsp)=0;	// Clone single node, just get same type back.
+    // ACCESSORS
+    AstNode*	lhsp() 	const { return op1p(); }
+    AstNode*	rhsp() 	const { return op2p(); }
    void	lhsp(AstNode* nodep)  { return setOp1p(nodep); }
    void	rhsp(AstNode* nodep)  { return setOp2p(nodep); }
    // METHODS
@@ -1349,9 +1400,9 @@ public:
 	: AstNodeMath(fl) {
 	setOp1p(lhs); setOp2p(rhs); setOp3p(ths); }
    ASTNODE_BASE_FUNCS(NodeTriop)
-    AstNode*	lhsp() 	const { return op1p()->castNode(); }
-    AstNode*	rhsp() 	const { return op2p()->castNode(); }
-    AstNode*	thsp() 	const { return op3p()->castNode(); }
+    AstNode*	lhsp() 	const { return op1p(); }
+    AstNode*	rhsp() 	const { return op2p(); }
+    AstNode*	thsp() 	const { return op3p(); }
    void	lhsp(AstNode* nodep)  { return setOp1p(nodep); }
    void	rhsp(AstNode* nodep)  { return setOp2p(nodep); }
    void	thsp(AstNode* nodep)  { return setOp3p(nodep); }
@@ -1393,9 +1444,9 @@ public:
    ASTNODE_BASE_FUNCS(NodeCond)
    virtual void numberOperate(V3Number& out, const V3Number& lhs, const V3Number& rhs, const V3Number& ths) {
 	if (lhs.isNeqZero()) out.opAssign(rhs); else out.opAssign(ths); }
-    AstNode*	condp() 	const { return op1p()->castNode(); }	// op1 = Condition
-    AstNode*	expr1p() 	const { return op2p()->castNode(); }	// op2 = If true...
-    AstNode*	expr2p() 	const { return op3p()->castNode(); }	// op3 = If false...
+    AstNode*	condp() 	const { return op1p(); }	// op1 = Condition
+    AstNode*	expr1p() 	const { return op2p(); }	// op2 = If true...
+    AstNode*	expr2p() 	const { return op3p(); }	// op3 = If false...
    virtual string emitVerilog() { return "%k(%l %f? %r %k: %t)"; }
    virtual string emitC() { return "VL_COND_%nq%lq%rq%tq(%nw,%lw,%rw,%tw, %P, %li, %ri, %ti)"; }
    virtual bool cleanOut() { return false; } // clean if e1 & e2 clean
@@ -1413,10 +1464,10 @@ public:
 	: AstNode(fl) {
 	setOp1p(lhs); setOp2p(rhs); setNOp3p(ths); }
    ASTNODE_BASE_FUNCS(NodePreSel)
-    AstNode*	lhsp() 	const { return op1p()->castNode(); }
+    AstNode*	lhsp() 	const { return op1p(); }
    AstNode*	fromp() const { return lhsp(); }
-    AstNode*	rhsp() 	const { return op2p()->castNode(); }
-    AstNode*	thsp() 	const { return op3p()->castNode(); }
+    AstNode*	rhsp() 	const { return op2p(); }
+    AstNode*	thsp() 	const { return op3p(); }
    AstAttrOf*	attrp() const { return op4p()->castAttrOf(); }
    void	lhsp(AstNode* nodep)  { return setOp1p(nodep); }
    void	rhsp(AstNode* nodep)  { return setOp2p(nodep); }
@@ -1430,7 +1481,7 @@ public:
 class AstNodeStmt : public AstNode {
    // Statement -- anything that's directly under a function
 public:
-    AstNodeStmt(FileLine* fl)
+    explicit AstNodeStmt(FileLine* fl)
 	: AstNode(fl) {}
    ASTNODE_BASE_FUNCS(NodeStmt)
    // METHODS
@@ -1448,8 +1499,8 @@ public:
    ASTNODE_BASE_FUNCS(NodeAssign)
    virtual AstNode*	cloneType(AstNode* lhsp, AstNode* rhsp)=0;	// Clone single node, just get same type back.
    // So iteration hits the RHS which is "earlier" in execution order, it's op1, not op2
-    AstNode* rhsp()		const { return op1p()->castNode(); }	// op1 = Assign from
-    AstNode* lhsp()		const { return op2p()->castNode(); }	// op2 = Assign to
+    AstNode* rhsp()		const { return op1p(); }	// op1 = Assign from
+    AstNode* lhsp()		const { return op2p(); }	// op2 = Assign to
    void rhsp(AstNode* np) { setOp1p(np); }
    void lhsp(AstNode* np) { setOp2p(np); }
    virtual bool hasDType() const { return true; }
@@ -1468,10 +1519,10 @@ public:
 	addNOp1p(initsp); setOp2p(condp); addNOp3p(incsp); addNOp4p(bodysp);
    }
    ASTNODE_BASE_FUNCS(NodeFor)
-    AstNode*	initsp()	const { return op1p()->castNode(); }	// op1= initial statements
-    AstNode*	condp()		const { return op2p()->castNode(); }	// op2= condition to continue
-    AstNode*	incsp()		const { return op3p()->castNode(); }	// op3= increment statements
-    AstNode*	bodysp()	const { return op4p()->castNode(); }	// op4= body of loop
+    AstNode*	initsp()	const { return op1p(); }	// op1= initial statements
+    AstNode*	condp()		const { return op2p(); }	// op2= condition to continue
+    AstNode*	incsp()		const { return op3p(); }	// op3= increment statements
+    AstNode*	bodysp()	const { return op4p(); }	// op4= body of loop
    virtual bool isGateOptimizable() const { return false; }
    virtual int  instrCount() const { return instrCountBranch(); }
    virtual V3Hash sameHash() const { return V3Hash(); }
@@ -1510,9 +1561,9 @@ public:
    }
    ASTNODE_BASE_FUNCS(NodeCase)
    virtual int   instrCount()	const { return instrCountBranch(); }
-    AstNode*	  exprp()	const { return op1p()->castNode(); }	// op1 = case condition <expression>
+    AstNode*	  exprp()	const { return op1p(); }	// op1 = case condition <expression>
    AstCaseItem*  itemsp()	const { return op2p()->castCaseItem(); }  // op2 = list of case expressions
-    AstNode*	  notParallelp() const { return op3p()->castNode(); }	// op3 = assertion code for non-full case's
+    AstNode*	  notParallelp() const { return op3p(); }	// op3 = assertion code for non-full case's
    void addItemsp(AstNode* nodep) { addOp2p(nodep); }
    void addNotParallelp(AstNode* nodep) { setOp3p(nodep); }
 };
@@ -1520,7 +1571,7 @@ public:
 class AstNodeSenItem : public AstNode {
    // An AstSenItem or AstSenGate
 public:
-    AstNodeSenItem(FileLine* fl) : AstNode(fl) {}
+    explicit AstNodeSenItem(FileLine* fl) : AstNode(fl) {}
    ASTNODE_BASE_FUNCS(NodeSenItem)
    virtual bool isClocked() const = 0;
    virtual bool isCombo() const = 0;
@@ -1574,7 +1625,7 @@ public:
    // Know no children, and hot function, so skip iterator for speed
    // See checkTreeIter also that asserts no children
    // cppcheck-suppress functionConst
-    void iterateChildren(AstNVisitor& v, AstNUser* vup=NULL) { }
+    void iterateChildren(AstNVisitor& v) { }
 };

 class AstNodeText : public AstNode {
@@ -1607,7 +1658,7 @@ private:
    static int	s_uniqueNum;	// Unique number assigned to each dtype during creation for IEEE matching
 public:
    // CONSTRUCTORS
-    AstNodeDType(FileLine* fl) : AstNode(fl) {
+    explicit AstNodeDType(FileLine* fl) : AstNode(fl) {
 	m_width=0; m_widthMin=0; m_generic=false;
    }
    ASTNODE_BASE_FUNCS(NodeDType)
@@ -1696,7 +1747,7 @@ private:
    AstNodeDType*	m_refDTypep;	// Elements of this type (after widthing)
    AstNode*	rangenp() const { return op2p(); }	// op2 = Array(s) of variable
 public:
-    AstNodeArrayDType(FileLine* fl) : AstNodeDType(fl) {
+    explicit AstNodeArrayDType(FileLine* fl) : AstNodeDType(fl) {
 	m_refDTypep = NULL;
    }
    ASTNODE_BASE_FUNCS(NodeArrayDType)
@@ -1705,7 +1756,7 @@ public:
    virtual const char* broken() const { BROKEN_RTN(!((m_refDTypep && !childDTypep() && m_refDTypep->brokeExists())
 						     || (!m_refDTypep && childDTypep()))); return NULL; }
    virtual void cloneRelink() { if (m_refDTypep && m_refDTypep->clonep()) {
-	m_refDTypep = m_refDTypep->clonep()->castNodeDType();
+	m_refDTypep = m_refDTypep->clonep();
    }}
    virtual bool same(AstNode* samep) const {
 	AstNodeArrayDType* sp = samep->castNodeArrayDType();
@@ -1741,9 +1792,9 @@ public:
    AstNodeSel(FileLine* fl, AstNode* fromp, AstNode* bitp)
 	:AstNodeBiop(fl, fromp, bitp) {}
    ASTNODE_BASE_FUNCS(NodeSel)
-    AstNode* fromp() const { return op1p()->castNode(); }	// op1 = Extracting what (NULL=TBD during parsing)
+    AstNode* fromp() const { return op1p(); }	// op1 = Extracting what (NULL=TBD during parsing)
    void fromp(AstNode* nodep) { setOp1p(nodep); }
-    AstNode* bitp() const { return op2p()->castNode(); }	// op2 = Msb selection expression
+    AstNode* bitp() const { return op2p(); }	// op2 = Msb selection expression
    void bitp(AstNode* nodep) { setOp2p(nodep); }
    int	     bitConst()	const;
    virtual bool hasDType() const { return true; }
@@ -1789,16 +1840,17 @@ public:
    virtual void dump(ostream& str=cout);
    virtual string name()	const { return m_name; }		// * = Var name
    virtual bool maybePointedTo() const { return true; }
+    virtual bool isGateOptimizable() const { return !((m_dpiExport || m_dpiImport) && !m_pure); }
    // {AstFunc only} op1 = Range output variable
    virtual void name(const string& name) 	{ m_name = name; }
    string cname() const { return m_cname; }
    void cname(const string& cname) { m_cname = cname; }
    // op1 = Output variable (functions only, NULL for tasks)
-    AstNode*	fvarp() 	const { return op1p()->castNode(); }
+    AstNode*	fvarp() 	const { return op1p(); }
    void 	addFvarp(AstNode* nodep) { addNOp1p(nodep); }
    bool	isFunction() const { return fvarp()!=NULL; }
    // op3 = Statements/Ports/Vars
-    AstNode*	stmtsp() 	const { return op3p()->castNode(); }	// op3 = List of statements
+    AstNode*	stmtsp() 	const { return op3p(); }	// op3 = List of statements
    void	addStmtsp(AstNode* nodep) { addNOp3p(nodep); }
    // op4 = scope name
    AstScopeName* scopeNamep() const { return op4p()->castScopeName(); }
@@ -1843,10 +1895,11 @@ public:
    ASTNODE_BASE_FUNCS(NodeFTaskRef)
    virtual const char* broken() const { BROKEN_RTN(m_taskp && !m_taskp->brokeExists()); return NULL; }
    virtual void cloneRelink() { if (m_taskp && m_taskp->clonep()) {
-	m_taskp = m_taskp->clonep()->castNodeFTask();
+	m_taskp = m_taskp->clonep();
    }}
    virtual void dump(ostream& str=cout);
    virtual string name()	const { return m_name; }		// * = Var name
+    virtual bool isGateOptimizable() const { return m_taskp && m_taskp->isGateOptimizable(); }
    string	dotted()	const { return m_dotted; }		// * = Scope name or ""
    string	prettyDotted() const { return prettyName(dotted()); }
    string	inlinedDots() const { return m_inlinedDots; }
@@ -1860,7 +1913,7 @@ public:
    // op1 = namep
    AstNode*	namep()		const { return op1p(); }
    // op2 = Pin interconnection list
-    AstNode*	pinsp() 	const { return op2p()->castNode(); }
+    AstNode*	pinsp() 	const { return op2p(); }
    void addPinsp(AstNode* nodep) { addOp2p(nodep); }
    // op3 = scope tracking
    AstScopeName* scopeNamep() const { return op3p()->castScopeName(); }
@@ -1892,7 +1945,7 @@ public:
    virtual void dump(ostream& str);
    virtual bool maybePointedTo() const { return true; }
    virtual string name()	const { return m_name; }
-    AstNode*	stmtsp() 	const { return op2p()->castNode(); }	// op2 = List of statements
+    AstNode*	stmtsp() 	const { return op2p(); }	// op2 = List of statements
    AstActive*  activesp()	const { return op3p()->castActive(); }	// op3 = List of i/sblocks
    // METHODS
    void addInlinesp(AstNode* nodep) { addOp1p(nodep); }
@@ -1942,8 +1995,8 @@ inline bool AstNode::isNeqZero()  { return (this->castConst() && this->castConst
 inline bool AstNode::isOne()      { return (this->castConst() && this->castConst()->num().isEqOne()); }
 inline bool AstNode::isAllOnes()  { return (this->castConst() && this->castConst()->isEqAllOnes()); }
 inline bool AstNode::isAllOnesV() { return (this->castConst() && this->castConst()->isEqAllOnesV()); }
-inline bool AstNode::sameTree(AstNode* node2p) { return sameTreeIter(node2p, true, false); }
-inline bool AstNode::sameGateTree(AstNode* node2p) { return sameTreeIter(node2p, true, true); }
+inline bool AstNode::sameTree(AstNode* node2p) { return sameTreeIter(this, node2p, true, false); }
+inline bool AstNode::sameGateTree(AstNode* node2p) { return sameTreeIter(this, node2p, true, true); }

 inline void AstNodeVarRef::init() { if (m_varp) dtypep(m_varp->dtypep()); }

@@ -1954,8 +2007,8 @@ inline int AstNodeArrayDType::elementsConst() const { return rangep()->elementsC
 inline VNumRange AstNodeArrayDType::declRange() const { return VNumRange(msb(), lsb(), rangep()->littleEndian()); }

 inline void AstIfaceRefDType::cloneRelink() {
-    if (m_cellp && m_cellp->clonep()) m_cellp = m_cellp->clonep()->castCell();
-    if (m_ifacep && m_ifacep->clonep()) m_ifacep = m_ifacep->clonep()->castIface();
-    if (m_modportp && m_modportp->clonep()) m_modportp = m_modportp->clonep()->castModport(); }
+    if (m_cellp && m_cellp->clonep()) m_cellp = m_cellp->clonep();
+    if (m_ifacep && m_ifacep->clonep()) m_ifacep = m_ifacep->clonep();
+    if (m_modportp && m_modportp->clonep()) m_modportp = m_modportp->clonep(); }

 #endif // Guard
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -53,7 +53,7 @@ const char* AstNodeVarRef::broken() const {
 }

 void AstNodeVarRef::cloneRelink() {
-    if (m_varp && m_varp->clonep()) { m_varp = m_varp->clonep()->castVar(); }
+    if (m_varp && m_varp->clonep()) { m_varp = m_varp->clonep(); }
 }

 int AstNodeSel::bitConst() const {
@@ -195,6 +195,8 @@ string AstVar::verilogKwd() const {
 	return "tri";
    } else if (varType()==AstVarType::WIRE) {
 	return "wire";
+    } else if (varType()==AstVarType::WREAL) {
+	return "wreal";
    } else {
 	return dtypep()->name();
    }
@@ -386,6 +388,7 @@ AstNodeDType* AstNodeDType::dtypeDimensionp(int dimension) {
    // TODO this function should be removed in favor of recursing the dtype(),
    // as that allows for more complicated data types.
    int dim = 0;
+    UDEBUGONLY(UASSERT(dynamic_cast<AstNode*>(this),"this should not be NULL"););
    for (AstNodeDType* dtypep=this; dtypep; ) {
 	dtypep = dtypep->skipRefp();  // Skip AstRefDType/AstTypedef, or return same node
 	if (AstNodeArrayDType* adtypep = dtypep->castNodeArrayDType()) {
@@ -420,6 +423,7 @@ AstNodeDType* AstNodeDType::dtypeDimensionp(int dimension) {

 uint32_t AstNodeDType::arrayUnpackedElements() {
    uint32_t entries=1;
+    UDEBUGONLY(UASSERT(dynamic_cast<AstNode*>(this),"this should not be NULL"););
    for (AstNodeDType* dtypep=this; dtypep; ) {
 	dtypep = dtypep->skipRefp();  // Skip AstRefDType/AstTypedef, or return same node
 	if (AstUnpackArrayDType* adtypep = dtypep->castUnpackArrayDType()) {
@@ -438,6 +442,7 @@ pair<uint32_t,uint32_t> AstNodeDType::dimensions(bool includeBasic) {
    // How many array dimensions (packed,unpacked) does this Var have?
    uint32_t packed = 0;
    uint32_t unpacked = 0;
+    UDEBUGONLY(UASSERT(dynamic_cast<AstNode*>(this),"this should not be NULL"););
    for (AstNodeDType* dtypep=this; dtypep; ) {
 	dtypep = dtypep->skipRefp();  // Skip AstRefDType/AstTypedef, or return same node
 	if (AstNodeArrayDType* adtypep = dtypep->castNodeArrayDType()) {
@@ -492,9 +497,9 @@ const char* AstScope::broken() const {
 }

 void AstScope::cloneRelink() {
-    if (m_aboveScopep && m_aboveScopep->clonep()) m_aboveScopep->clonep()->castScope();
-    if (m_aboveCellp && m_aboveCellp->clonep()) m_aboveCellp->clonep()->castCell();
-    if (m_modp && ((AstNode*)m_modp)->clonep()) ((AstNode*)m_modp)->clonep()->castNodeModule();
+    if (m_aboveScopep && m_aboveScopep->clonep()) m_aboveScopep->clonep();
+    if (m_aboveCellp && m_aboveCellp->clonep()) m_aboveCellp->clonep();
+    if (m_modp && ((AstNode*)m_modp)->clonep()) ((AstNode*)m_modp)->clonep();
 }

 string AstScope::nameDotless() const {
@@ -506,9 +511,9 @@ string AstScope::nameDotless() const {
    return out;
 }

-string AstScopeName::scopePrettyName() const {
+string AstScopeName::scopePrettyNameFormatter(AstText* scopeTextp) const {
    string out;
-    for (AstText* textp=scopeAttrp(); textp; textp=textp->nextp()->castText()) {
+    for (AstText* textp=scopeTextp; textp; textp=textp->nextp()->castText()) {
 	out += textp->text();
    }
    // TOP will be replaced by top->name()
@@ -518,27 +523,9 @@ string AstScopeName::scopePrettyName() const {
    return AstNode::prettyName(out);
 }

-string AstScopeName::scopeSymName() const {
+string AstScopeName::scopeNameFormatter(AstText* scopeTextp) const {
    string out;
-    for (AstText* textp=scopeAttrp(); textp; textp=textp->nextp()->castText()) {
-	out += textp->text();
-    }
-    if (out.substr(0,10) == "__DOT__TOP") out.replace(0,10,"");
-    if (out.substr(0,7) == "__DOT__") out.replace(0,7,"");
-    if (out.substr(0,1) == ".") out.replace(0,1,"");
-    string::size_type pos;
-    while ((pos=out.find(".")) != string::npos) {
-	out.replace(pos, 1, "__");
-    }
-    while ((pos=out.find("__DOT__")) != string::npos) {
-	out.replace(pos, 7, "__");
-    }
-    return out;
-}
-
-string AstScopeName::scopeDpiName() const {
-    string out;
-    for (AstText* textp=scopeEntrp(); textp; textp=textp->nextp()->castText()) {
+    for (AstText* textp=scopeTextp; textp; textp=textp->nextp()->castText()) {
 	out += textp->text();
    }
    if (out.substr(0,10) == "__DOT__TOP") out.replace(0,10,"");
@@ -992,6 +979,7 @@ void AstVar::dump(ostream& str) {
    if (attrFileDescr()) str<<" [aFD]";
    if (isFuncReturn()) str<<" [FUNCRTN]";
    else if (isFuncLocal()) str<<" [FUNC]";
+    if (!attrClocker().unknown()) str<<" ["<<attrClocker().ascii()<<"] ";
    str<<" "<<varType();
 }
 void AstSenTree::dump(ostream& str) {
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -56,7 +56,7 @@ public:
 	m_anyFuncInBegin = false;
    }
    ~BeginState() {}
-    void userMarkChanged(AstNodeFTask* nodep) {
+    void userMarkChanged(AstNode* nodep) {
 	nodep->user1(true);
 	m_anyFuncInBegin = true;
    }
@@ -84,13 +84,13 @@ private:
    }

    // VISITORS
-    virtual void visit(AstNodeModule* nodep, AstNUser*) {
+    virtual void visit(AstNodeModule* nodep) {
 	m_modp = nodep;
 	m_repeatNum = 0;
 	nodep->iterateChildren(*this);
 	m_modp = NULL;
    }
-    virtual void visit(AstNodeFTask* nodep, AstNUser*) {
+    virtual void visit(AstNodeFTask* nodep) {
 	UINFO(8,"  "<<nodep<<endl);
 	// Rename it
 	if (m_unnamedScope != "") {
@@ -113,7 +113,7 @@ private:
 	m_namedScope = oldScope;
 	m_unnamedScope = oldUnnamed;
    }
-    virtual void visit(AstBegin* nodep, AstNUser*) {
+    virtual void visit(AstBegin* nodep) {
 	// Begin blocks were only useful in variable creation, change names and delete
 	UINFO(8,"  "<<nodep<<endl);
 	string oldScope = m_namedScope;
@@ -160,21 +160,23 @@ private:
 	} else {
 	    nodep->unlinkFrBack();
 	}
-	pushDeletep(nodep); nodep=NULL;
+	pushDeletep(nodep); VL_DANGLING(nodep);
    }
-    virtual void visit(AstVar* nodep, AstNUser*) {
+    virtual void visit(AstVar* nodep) {
 	if (m_unnamedScope != "") {
 	    // Rename it
 	    nodep->name(m_unnamedScope+"__DOT__"+nodep->name());
+	    m_statep->userMarkChanged(nodep);
 	    // Move to module
 	    nodep->unlinkFrBack();
 	    if (m_ftaskp) m_ftaskp->addStmtsp(nodep);   // Begins under funcs just move into the func
 	    else m_modp->addStmtp(nodep);
 	}
    }
-    virtual void visit(AstCell* nodep, AstNUser*) {
+    virtual void visit(AstCell* nodep) {
 	UINFO(8,"   CELL "<<nodep<<endl);
 	if (m_namedScope != "") {
+	    m_statep->userMarkChanged(nodep);
 	    // Rename it
 	    nodep->name(m_namedScope+"__DOT__"+nodep->name());
 	    UINFO(8,"     rename to "<<nodep->name()<<endl);
@@ -182,8 +184,16 @@ private:
 	    nodep->unlinkFrBack();
 	    m_modp->addStmtp(nodep);
 	}
+	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstScopeName* nodep, AstNUser*) {
+    virtual void visit(AstVarXRef* nodep) {
+	UINFO(9, "   VARXREF "<<nodep<<endl);
+	if (m_namedScope != "" && nodep->inlinedDots() == "") {
+	    nodep->inlinedDots(m_namedScope);
+	    UINFO(9, "    rescope to "<<nodep<<endl);
+	}
+    }
+    virtual void visit(AstScopeName* nodep) {
 	// If there's a %m in the display text, we add a special node that will contain the name()
 	// Similar code in V3Inline
 	if (nodep->user1SetOnce()) return;  // Don't double-add text's
@@ -196,13 +206,13 @@ private:
 	}
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstCoverDecl* nodep, AstNUser*) {
+    virtual void visit(AstCoverDecl* nodep) {
 	// Don't need to fix path in coverage statements, they're not under
 	// any BEGINs, but V3Coverage adds them all under the module itself.
 	nodep->iterateChildren(*this);
    }
    // VISITORS - LINT CHECK
-    virtual void visit(AstIf* nodep, AstNUser*) { // Note not AstNodeIf; other types don't get covered
+    virtual void visit(AstIf* nodep) { // Note not AstNodeIf; other types don't get covered
 	// Check IFDEPTH warning - could be in other transform files if desire
 	int prevIfDepth = m_ifDepth;
 	if (m_ifDepth == -1 || v3Global.opt.ifDepth()<1) { // Turned off
@@ -215,8 +225,8 @@ private:
 	}
 	nodep->iterateChildren(*this);
 	m_ifDepth = prevIfDepth;
-     }
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    }
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }
 public:
@@ -242,15 +252,30 @@ private:
    //   AstNodeFTask::user1p		// Node replaced, rename it

    // VISITORS
-    virtual void visit(AstNodeFTaskRef* nodep, AstNUser*) {
+    virtual void visit(AstNodeFTaskRef* nodep) {
 	if (nodep->taskp()->user1()) { // It was converted
 	    UINFO(9, "    relinkFTask "<<nodep<<endl);
 	    nodep->name(nodep->taskp()->name());
 	}
 	nodep->iterateChildren(*this);
    }
+    virtual void visit(AstVarRef* nodep) {
+	if (nodep->varp()->user1()) { // It was converted
+	    UINFO(9, "    relinVarRef "<<nodep<<endl);
+	    nodep->name(nodep->varp()->name());
+	}
+	nodep->iterateChildren(*this);
+    }
+    virtual void visit(AstIfaceRefDType* nodep) {
+	// May have changed cell names
+	// TypeTable is always after all modules, so names are stable
+	UINFO(8,"   IFACEREFDTYPE "<<nodep<<endl);
+	if (nodep->cellp()) nodep->cellName(nodep->cellp()->name());
+	UINFO(8,"       rename to "<<nodep<<endl);
+	nodep->iterateChildren(*this);
+    }
    //--------------------
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }
 public:
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -75,7 +75,7 @@ private:
    }

    // VISITORS
-    virtual void visit(AstNodeIf* nodep, AstNUser*) {
+    virtual void visit(AstNodeIf* nodep) {
 	UINFO(4," IF: "<<nodep<<endl);
 	int lastLikely = m_likely;
 	int lastUnlikely = m_unlikely;
@@ -101,17 +101,17 @@ private:
 	m_likely = lastLikely;
 	m_unlikely = lastUnlikely;
    }
-    virtual void visit(AstCCall* nodep, AstNUser*) {
+    virtual void visit(AstCCall* nodep) {
 	checkUnlikely(nodep);
 	nodep->funcp()->user1Inc();
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstCFunc* nodep, AstNUser*) {
+    virtual void visit(AstCFunc* nodep) {
 	checkUnlikely(nodep);
 	m_cfuncsp.push_back(nodep);
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	checkUnlikely(nodep);
 	nodep->iterateChildren(*this);
    }
@@ -128,7 +128,7 @@ private:

 public:
    // CONSTUCTORS
-    BranchVisitor(AstNetlist* nodep) {
+    explicit BranchVisitor(AstNetlist* nodep) {
 	reset();
 	nodep->iterateChildren(*this);
 	calc_tasks();
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -186,14 +186,18 @@ private:
    // NODE STATE
    //  Nothing!	// This may be called deep inside other routines
    //			// so userp and friends may not be used
-    // VISITORS
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    // METHODS
+    void processAndIterate(AstNode* nodep) {
 	BrokenTable::addInTree(nodep, nodep->maybePointedTo());
 	nodep->iterateChildrenConst(*this);
    }
+    // VISITORS
+    virtual void visit(AstNode* nodep) {
+	processAndIterate(nodep);
+    }
 public:
    // CONSTUCTORS
-    BrokenMarkVisitor(AstNetlist* nodep) {
+    explicit BrokenMarkVisitor(AstNetlist* nodep) {
 	nodep->accept(*this);
    }
    virtual ~BrokenMarkVisitor() {}
@@ -210,7 +214,7 @@ private:
 	    nodep->v3fatalSrc("Width != WidthMin");
 	}
    }
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    void processAndIterate(AstNode* nodep) {
 	BrokenTable::setUnder(nodep,true);
 	if (const char* whyp=nodep->broken()) {
 	    nodep->v3fatalSrc("Broken link in node (or something without maybePointedTo): "<<whyp);
@@ -232,9 +236,12 @@ private:
 	nodep->iterateChildrenConst(*this);
 	BrokenTable::setUnder(nodep,false);
    }
+    virtual void visit(AstNode* nodep) {
+	processAndIterate(nodep);
+    }
 public:
    // CONSTUCTORS
-    BrokenCheckVisitor(AstNetlist* nodep) {
+    explicit BrokenCheckVisitor(AstNetlist* nodep) {
 	nodep->accept(*this);
    }
    virtual ~BrokenCheckVisitor() {}
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -0,0 +1,117 @@
+// -*- mode: C++; c-file-style: "cc-mode" -*-
+//*************************************************************************
+// DESCRIPTION: Verilator: Generate C language constructors and AstCReset nodes.
+//
+// Code available from: http://www.veripool.org/verilator
+//
+//*************************************************************************
+//
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
+// redistribute it and/or modify it under the terms of either the GNU
+// Lesser General Public License Version 3 or the Perl Artistic License
+// Version 2.0.
+//
+// Verilator is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+//*************************************************************************
+// V3CCtors's Transformations:
+//	Iterates over all modules and
+// 	for all AstVar, create a creates a AstCReset node in an _ctor_var_reset AstCFunc.
+//	for all AstCoverDecl, move the declaration into a _configure_coverage AstCFunc.
+//	For each variable that needs reset, add a AstCReset node.
+//
+//	This transformation honors outputSplitCFuncs.
+//*************************************************************************
+#include "config_build.h"
+#include "verilatedos.h"
+#include <cstdio>
+#include <cstdarg>
+#include <unistd.h>
+#include <cmath>
+#include <map>
+#include <vector>
+#include <algorithm>
+
+#include "V3Global.h"
+#include "V3EmitCBase.h"
+#include "V3CCtors.h"
+
+class V3CCtorsVisitor {
+private:
+    string 		m_basename;
+    string 		m_argsp;
+    string 		m_callargsp;
+    AstNodeModule*	m_modp;		// Current module
+    AstCFunc*		m_tlFuncp;	// Top level function being built
+    AstCFunc*		m_funcp;	// Current function
+    int			m_numStmts;	// Number of statements output
+    int			m_funcNum;	// Function number being built
+
+public:
+    void add(AstNode* nodep) {
+	if (v3Global.opt.outputSplitCFuncs()
+	    && v3Global.opt.outputSplitCFuncs() < m_numStmts) {
+	    m_funcp = NULL;
+	}
+	if (!m_funcp) {
+	    m_funcp = new AstCFunc(m_modp->fileline(), m_basename + "_" + cvtToStr(++m_funcNum), NULL, "void");
+	    m_funcp->isStatic(false);
+	    m_funcp->declPrivate(true);
+	    m_funcp->slow(true);
+	    m_funcp->argTypes(m_argsp);
+	    m_modp->addStmtp(m_funcp);
+
+	    // Add a top call to it
+	    AstCCall* callp = new AstCCall(m_modp->fileline(), m_funcp);
+	    callp->argTypes(m_callargsp);
+
+	    m_tlFuncp->addStmtsp(callp);
+	    m_numStmts = 0;
+	}
+	m_funcp->addStmtsp(nodep);
+	m_numStmts += 1;
+    }
+
+    V3CCtorsVisitor(AstNodeModule* nodep, string basename, string argsp="", string callargsp="") {
+	m_basename = basename;
+	m_argsp = argsp;
+	m_callargsp = callargsp;
+	m_modp = nodep;
+	m_numStmts = 0;
+	m_funcNum = 0;
+	m_tlFuncp = new AstCFunc(nodep->fileline(), basename, NULL, "void");
+	m_tlFuncp->declPrivate(true);
+	m_tlFuncp->isStatic(false);
+	m_tlFuncp->slow(true);
+	m_tlFuncp->argTypes(m_argsp);
+	m_funcp = m_tlFuncp;
+	m_modp->addStmtp(m_tlFuncp);
+    }
+};
+
+//######################################################################
+
+void V3CCtors::cctorsAll() {
+    UINFO(2,__FUNCTION__<<": "<<endl);
+    for (AstNodeModule* modp = v3Global.rootp()->modulesp(); modp; modp=modp->nextp()->castNodeModule()) {
+	// Process each module in turn
+	V3CCtorsVisitor var_reset (modp, "_ctor_var_reset");
+	V3CCtorsVisitor configure_coverage (modp, "_configure_coverage",
+						   EmitCBaseVisitor::symClassVar()+ ", bool first", "vlSymsp, first");
+
+	for (AstNode* np = modp->stmtsp(); np; np = np->nextp()) {
+	    AstVar* varp = np->castVar();
+	    if (varp) var_reset.add(new AstCReset(varp->fileline(), new AstVarRef(varp->fileline(), varp, true)));
+	    AstCoverDecl* coverp = np->castCoverDecl();
+	    if (coverp) {
+		AstNode* backp = coverp->backp();
+		coverp->unlinkFrBack();
+		configure_coverage.add(coverp);
+		np = backp;
+	    }
+	}
+    }
+}
@@ -0,0 +1,36 @@
+// -*- mode: C++; c-file-style: "cc-mode" -*-
+//*************************************************************************
+// DESCRIPTION: Verilator: Emit CFunc's for class construction and configuration
+//
+// Code available from: http://www.veripool.org/verilator
+//
+//*************************************************************************
+//
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
+// redistribute it and/or modify it under the terms of either the GNU
+// Lesser General Public License Version 3 or the Perl Artistic License
+// Version 2.0.
+//
+// Verilator is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+//*************************************************************************
+
+#ifndef _V3CCTORS_H_
+#define _V3CCTORS_H_ 1
+#include "config_build.h"
+#include "verilatedos.h"
+#include "V3Error.h"
+#include "V3Ast.h"
+
+//============================================================================
+
+class V3CCtors {
+public:
+    static void cctorsAll();
+};
+
+
+#endif // Guard
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -65,7 +65,7 @@ private:
 	return level;
    }

-    virtual void visit(AstNodeCase* nodep, AstNUser*) {
+    virtual void visit(AstNodeCase* nodep) {
 	if (nodep->castCase() && nodep->castCase()->casex()) {
 	    nodep->v3warn(CASEX,"Suggest casez (with ?'s) in place of casex (with X's)");
 	}
@@ -90,7 +90,7 @@ private:
 	    m_caseExprp = NULL;
 	}
    }
-    virtual void visit(AstConst* nodep, AstNUser*) {
+    virtual void visit(AstConst* nodep) {
 	// See also neverItem
 	if (m_caseExprp && nodep->num().isFourState()) {
 	    if (m_caseExprp->castGenCase()) {
@@ -107,12 +107,12 @@ private:
 	    }
 	}
    }
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }
 public:
    // CONSTUCTORS
-    CaseLintVisitor(AstNodeCase* nodep) {
+    explicit CaseLintVisitor(AstNodeCase* nodep) {
 	m_caseExprp = NULL;
 	nodep->accept(*this);
    }
@@ -246,7 +246,7 @@ private:
 		if (m_valueItem[a] != m_valueItem[b]) { same=false; break; }
 	    }
 	    if (same) {
-		tree1p->deleteTree(); tree1p=NULL;
+		tree1p->deleteTree(); VL_DANGLING(tree1p);
 		return tree0p;
 	    }

@@ -295,8 +295,8 @@ private:

 	if (ifrootp) nodep->replaceWith(ifrootp);
 	else nodep->unlinkFrBack();
-	nodep->deleteTree(); nodep=NULL;
-	cexprp->deleteTree(); cexprp=NULL;
+	nodep->deleteTree(); VL_DANGLING(nodep);
+	cexprp->deleteTree(); VL_DANGLING(cexprp);
 	if (debug()>=9) ifrootp->dumpTree(cout,"    _simp: ");
    }

@@ -327,7 +327,7 @@ private:
 		    AstConst* iconstp = icondp->castConst();
 		    if (iconstp && neverItem(nodep, iconstp)) {
 			// X in casez can't ever be executed
-			icondp->deleteTree(); icondp=NULL; iconstp=NULL;
+			icondp->deleteTree(); VL_DANGLING(icondp); VL_DANGLING(iconstp);
 			// For simplicity, make expression that is not equal, and let later
 			// optimizations remove it
 			condp = new AstConst(itemp->fileline(), AstConst::LogicFalse());
@@ -351,7 +351,7 @@ private:
 			AstNode* and2p = new AstAnd(itemp->fileline(),
 						    new AstConst(itemp->fileline(), numval),
 						    new AstConst(itemp->fileline(), nummask));
-			icondp->deleteTree(); icondp=NULL; iconstp=NULL;
+			icondp->deleteTree(); VL_DANGLING(icondp); VL_DANGLING(iconstp);
 			condp = AstEq::newTyped(itemp->fileline(), and1p, and2p);
 		    } else {
 			// Not a caseX mask, we can simply build CASEEQ(cexpr icond)
@@ -369,7 +369,7 @@ private:
 		itemp->condsp(ifexprp);
 	    }
 	}
-	cexprp->deleteTree(); cexprp=NULL;
+	cexprp->deleteTree(); VL_DANGLING(cexprp);
 	if (!hadDefault) {
 	    // If there was no default, add a empty one, this greatly simplifies below code
 	    // and constant propagation will just eliminate it for us later.
@@ -408,10 +408,9 @@ private:
 		}
 	    }
 	    {   // Make the new lower IF and attach in the tree
-		AstNode* itemexprp = ifexprp;  ifexprp=NULL;
+		AstNode* itemexprp = ifexprp; VL_DANGLING(ifexprp);
 		if (depth == (CASE_ENCODER_GROUP_DEPTH)) { // End of group - can skip the condition
-		    itemexprp->deleteTree(); itemexprp=NULL;
-		    // cppcheck-suppress redundantAssignment
+		    itemexprp->deleteTree(); VL_DANGLING(itemexprp);
 		    itemexprp = new AstConst(itemp->fileline(), AstConst::LogicTrue());
 		}
 		AstIf* newp = new AstIf(itemp->fileline(), itemexprp, istmtsp, NULL);
@@ -427,7 +426,7 @@ private:
 	if (debug()>=9) grouprootp->dumpTree(cout,"     _new: ");
 	if (grouprootp) nodep->replaceWith(grouprootp);
 	else nodep->unlinkFrBack();
-	nodep->deleteTree(); nodep=NULL;
+	nodep->deleteTree(); VL_DANGLING(nodep);
    }

    void replaceCaseParallel(AstCase* nodep, bool noOverlapsAllCovered) {
@@ -452,7 +451,7 @@ private:
    }

    // VISITORS
-    virtual void visit(AstCase* nodep, AstNUser*) {
+    virtual void visit(AstCase* nodep) {
 	V3Case::caseLint(nodep);
 	nodep->iterateChildren(*this);
 	if (debug()>=9) nodep->dumpTree(cout," case_old: ");
@@ -460,22 +459,21 @@ private:
 	    // It's a simple priority encoder or complete statement
 	    // we can make a tree of statements to avoid extra comparisons
 	    ++m_statCaseFast;
-	    replaceCaseFast(nodep); nodep=NULL;
+	    replaceCaseFast(nodep); VL_DANGLING(nodep);
 	} else {
 	    ++m_statCaseSlow;
-	    // cppcheck-supporess uselessAssignmentPtrArg
-	    replaceCaseComplicated(nodep); nodep=NULL;
+	    replaceCaseComplicated(nodep); VL_DANGLING(nodep);
 	}
    }
    //--------------------
    // Default: Just iterate
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }

 public:
    // CONSTUCTORS
-    CaseVisitor(AstNetlist* nodep) {
+    explicit CaseVisitor(AstNetlist* nodep) {
 	m_caseNoOverlapsAllCovered = false;
 	nodep->accept(*this);
    }
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2004-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2004-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -107,19 +107,19 @@ private:
    }

    // VISITORS
-    virtual void visit(AstNodeUniop* nodep, AstNUser*) {
+    virtual void visit(AstNodeUniop* nodep) {
 	nodep->iterateChildren(*this);
 	nodep->user1(nodep->lhsp()->user1());
 	if (nodep->sizeMattersLhs()) insureCast(nodep->lhsp());
    }
-    virtual void visit(AstNodeBiop* nodep, AstNUser*) {
+    virtual void visit(AstNodeBiop* nodep) {
 	nodep->iterateChildren(*this);
 	nodep->user1(nodep->lhsp()->user1()
 		    | nodep->rhsp()->user1());
 	if (nodep->sizeMattersLhs()) insureCast(nodep->lhsp());
 	if (nodep->sizeMattersRhs()) insureCast(nodep->rhsp());
    }
-    virtual void visit(AstNodeTriop* nodep, AstNUser*) {
+    virtual void visit(AstNodeTriop* nodep) {
 	nodep->iterateChildren(*this);
 	nodep->user1(nodep->lhsp()->user1()
 		    | nodep->rhsp()->user1()
@@ -128,12 +128,12 @@ private:
 	if (nodep->sizeMattersRhs()) insureCast(nodep->rhsp());
 	if (nodep->sizeMattersThs()) insureCast(nodep->thsp());
    }
-    virtual void visit(AstCCast* nodep, AstNUser*) {
+    virtual void visit(AstCCast* nodep) {
 	nodep->iterateChildren(*this);
 	insureLower32Cast(nodep);
 	nodep->user1(1);
    }
-    virtual void visit(AstNegate* nodep, AstNUser*) {
+    virtual void visit(AstNegate* nodep) {
 	nodep->iterateChildren(*this);
 	nodep->user1(nodep->lhsp()->user1());
 	if (nodep->lhsp()->widthMin()==1) {
@@ -145,7 +145,7 @@ private:
 	    insureCast(nodep->lhsp());
 	}
    }
-    virtual void visit(AstVarRef* nodep, AstNUser*) {
+    virtual void visit(AstVarRef* nodep) {
 	if (!nodep->lvalue()
 	    && !nodep->backp()->castCCast()
 	    && nodep->backp()->castNodeMath()
@@ -158,7 +158,7 @@ private:
 	}
 	nodep->user1(1);
    }
-    virtual void visit(AstConst* nodep, AstNUser*) {
+    virtual void visit(AstConst* nodep) {
 	// Constants are of unknown size if smaller than 33 bits, becase
 	// we're too lazy to wrap every constant in the universe in
 	// ((IData)#).
@@ -166,17 +166,17 @@ private:
    }

    // NOPs
-    virtual void visit(AstVar* nodep, AstNUser*) {}
+    virtual void visit(AstVar* nodep) {}

    //--------------------
    // Default: Just iterate
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }

 public:
    // CONSTUCTORS
-    CastVisitor(AstNetlist* nodep) {
+    explicit CastVisitor(AstNetlist* nodep) {
 	nodep->accept(*this);
    }
    virtual ~CastVisitor() {}
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2004-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2004-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -138,7 +138,7 @@ private:
    ofstream*		m_ofp;		// Output file
    string		m_prefix;

-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	*m_ofp<<m_prefix;
 	if (nodep->user3()) *m_ofp<<" %%";
 	else *m_ofp<<"  ";
@@ -172,7 +172,7 @@ private:
    int		m_maxLineno;
    size_t	m_maxFilenameLen;

-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
 	// Keeping line+filename lengths separate is much faster than calling ascii().length()
 	if (nodep->fileline()->lineno() >= m_maxLineno) {
@@ -184,7 +184,7 @@ private:
    }
 public:
    // CONSTUCTORS
-    CdcWidthVisitor(AstNode* nodep) {
+    explicit CdcWidthVisitor(AstNode* nodep) {
 	m_maxLineno = 0;
 	m_maxFilenameLen = 0;
 	nodep->accept(*this);
@@ -496,7 +496,7 @@ private:
 	}

 	string filename = v3Global.opt.makeDir()+"/"+v3Global.opt.prefix()+"__cdc_edges.txt";
-	const auto_ptr<ofstream> ofp (V3File::new_ofstream(filename));
+	const VL_UNIQUE_PTR<ofstream> ofp (V3File::new_ofstream(filename));
 	if (ofp->fail()) v3fatalSrc("Can't write "<<filename);
 	*ofp<<"Edge Report for "<<v3Global.opt.prefix()<<endl;

@@ -604,19 +604,19 @@ private:
    }

    // VISITORS
-    virtual void visit(AstNodeModule* nodep, AstNUser*) {
+    virtual void visit(AstNodeModule* nodep) {
 	m_modp = nodep;
 	nodep->iterateChildren(*this);
 	m_modp = NULL;
    }
-    virtual void visit(AstScope* nodep, AstNUser*) {
+    virtual void visit(AstScope* nodep) {
 	UINFO(4," SCOPE "<<nodep<<endl);
 	m_scopep = nodep;
 	m_logicVertexp = NULL;
 	nodep->iterateChildren(*this);
 	m_scopep = NULL;
    }
-    virtual void visit(AstActive* nodep, AstNUser*) {
+    virtual void visit(AstActive* nodep) {
 	// Create required blocks and add to module
 	UINFO(4,"  BLOCK  "<<nodep<<endl);
 	AstNode::user2ClearTree();
@@ -627,7 +627,7 @@ private:
 	m_domainp = NULL;
 	AstNode::user2ClearTree();
    }
-    virtual void visit(AstNodeVarRef* nodep, AstNUser*) {
+    virtual void visit(AstNodeVarRef* nodep) {
 	if (m_scopep) {
 	    if (!m_logicVertexp) nodep->v3fatalSrc("Var ref not under a logic block\n");
 	    AstVarScope* varscp = nodep->varScopep();
@@ -655,78 +655,78 @@ private:
 	    }
 	}
    }
-    virtual void visit(AstAssignDly* nodep, AstNUser*) {
+    virtual void visit(AstAssignDly* nodep) {
 	m_inDly = true;
 	nodep->iterateChildren(*this);
 	m_inDly = false;
    }
-    virtual void visit(AstSenItem* nodep, AstNUser*) {
+    virtual void visit(AstSenItem* nodep) {
 	// Note we look at only AstSenItems, not AstSenGate's
 	// The gating term of a AstSenGate is normal logic
 	m_inSenItem = true;
 	nodep->iterateChildren(*this);
 	m_inSenItem = false;
    }
-    virtual void visit(AstAlways* nodep, AstNUser*) {
+    virtual void visit(AstAlways* nodep) {
 	iterateNewStmt(nodep);
    }
-    virtual void visit(AstAlwaysPublic* nodep, AstNUser*) {
+    virtual void visit(AstAlwaysPublic* nodep) {
 	// CDC doesn't care about public variables
    }
-    virtual void visit(AstCFunc* nodep, AstNUser*) {
+    virtual void visit(AstCFunc* nodep) {
 	iterateNewStmt(nodep);
    }
-    virtual void visit(AstSenGate* nodep, AstNUser*) {
+    virtual void visit(AstSenGate* nodep) {
 	// First handle the clock part will be handled in a minute by visit AstSenItem
 	// The logic gating term is delt with as logic
 	iterateNewStmt(nodep);
    }
-    virtual void visit(AstAssignAlias* nodep, AstNUser*) {
+    virtual void visit(AstAssignAlias* nodep) {
 	iterateNewStmt(nodep);
    }
-    virtual void visit(AstAssignW* nodep, AstNUser*) {
+    virtual void visit(AstAssignW* nodep) {
 	iterateNewStmt(nodep);
    }

    // Math that shouldn't cause us to clear hazard
-    virtual void visit(AstConst* nodep, AstNUser*) { }
-    virtual void visit(AstReplicate* nodep, AstNUser*) {
+    virtual void visit(AstConst* nodep) { }
+    virtual void visit(AstReplicate* nodep) {
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstConcat* nodep, AstNUser*) {
+    virtual void visit(AstConcat* nodep) {
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstNot* nodep, AstNUser*) {
+    virtual void visit(AstNot* nodep) {
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstSel* nodep, AstNUser*) {
+    virtual void visit(AstSel* nodep) {
 	if (!nodep->lsbp()->castConst()) setNodeHazard(nodep);
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstNodeSel* nodep, AstNUser*) {
+    virtual void visit(AstNodeSel* nodep) {
 	if (!nodep->bitp()->castConst()) setNodeHazard(nodep);
 	nodep->iterateChildren(*this);
    }

    // Ignores
-    virtual void visit(AstInitial* nodep, AstNUser*) { }
-    virtual void visit(AstTraceInc* nodep, AstNUser*) { }
-    virtual void visit(AstCoverToggle* nodep, AstNUser*) { }
-    virtual void visit(AstNodeDType* nodep, AstNUser*) { }
+    virtual void visit(AstInitial* nodep) { }
+    virtual void visit(AstTraceInc* nodep) { }
+    virtual void visit(AstCoverToggle* nodep) { }
+    virtual void visit(AstNodeDType* nodep) { }

    //--------------------
    // Default
-    virtual void visit(AstNodeMath* nodep, AstNUser*) {
+    virtual void visit(AstNodeMath* nodep) {
 	setNodeHazard(nodep);
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }

 public:
    // CONSTUCTORS
-    CdcVisitor(AstNode* nodep) {
+    explicit CdcVisitor(AstNode* nodep) {
 	m_logicVertexp = NULL;
 	m_scopep = NULL;
 	m_modp = NULL;
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -51,12 +51,54 @@ public:
    AstNodeModule*	m_topModp;	// Top module
    AstScope*		m_scopetopp;	// Scope under TOPSCOPE
    AstCFunc*		m_chgFuncp;	// Change function we're building
+    AstCFunc*		m_tlChgFuncp;	// Top level change function we're building
+    int			m_numStmts;     // Number of statements added to m_chgFuncp
+    int 		m_funcNum;	// Number of change functions emitted
+
    ChangedState() {
 	m_topModp = NULL;
 	m_chgFuncp = NULL;
 	m_scopetopp = NULL;
+	m_tlChgFuncp = NULL;
+	m_numStmts = 0;
+	m_funcNum = 0;
    }
    ~ChangedState() {}
+
+    void maybeCreateChgFuncp() {
+	// Don't create an extra function call if splitting is disabled
+	if (!v3Global.opt.outputSplitCFuncs()) {
+	    m_chgFuncp = m_tlChgFuncp;
+	    return;
+	}
+	if (!m_chgFuncp || v3Global.opt.outputSplitCFuncs() < m_numStmts) {
+	    m_chgFuncp = new AstCFunc(m_scopetopp->fileline(), "_change_request_" + cvtToStr(++m_funcNum), m_scopetopp, "QData");
+	    m_chgFuncp->argTypes(EmitCBaseVisitor::symClassVar());
+	    m_chgFuncp->symProlog(true);
+	    m_chgFuncp->declPrivate(true);
+	    m_scopetopp->addActivep(m_chgFuncp);
+
+	    // Add a top call to it
+	    AstCCall* callp = new AstCCall(m_scopetopp->fileline(), m_chgFuncp);
+	    callp->argTypes("vlSymsp");
+
+	    if (!m_tlChgFuncp->stmtsp()) {
+		m_tlChgFuncp->addStmtsp(new AstCReturn(m_scopetopp->fileline(), callp));
+	    } else {
+		AstCReturn* returnp = m_tlChgFuncp->stmtsp()->castCReturn();
+		if (!returnp) m_scopetopp->v3fatalSrc("Lost CReturn in top change function");
+		// This is currently using AstLogOr which will shortcut the evaluation if
+		// any function returns true. This is likely what we want and is similar to the logic already in use
+		// inside V3EmitC, however, it also means that verbose logging may miss to print change detect variables.
+		AstNode* newp = new AstCReturn(m_scopetopp->fileline(),
+					       new AstLogOr(m_scopetopp->fileline(), callp,
+							    returnp->lhsp()->unlinkFrBack()));
+		returnp->replaceWith(newp);
+		returnp->deleteTree(); VL_DANGLING(returnp);
+	    }
+	    m_numStmts = 0;
+	}
+    }
 };

 //######################################################################
@@ -87,6 +129,8 @@ private:
 			   <<"... Could recompile with DETECTARRAY_MAX_INDEXES increased"<<endl);
 	    return;
 	}
+	m_statep->maybeCreateChgFuncp();
+
 	AstChangeDet* changep = new AstChangeDet (m_vscp->fileline(),
 						  m_varEqnp->cloneTree(true),
 						  m_newRvEqnp->cloneTree(true), false);
@@ -95,15 +139,17 @@ private:
 					  m_newLvEqnp->cloneTree(true),
 					  m_varEqnp->cloneTree(true));
 	m_statep->m_chgFuncp->addFinalsp(initp);
+	EmitCBaseCounterVisitor visitor(initp);
+	m_statep->m_numStmts += visitor.count();
    }

-    virtual void visit(AstBasicDType* nodep, AstNUser*) {
+    virtual void visit(AstBasicDType* nodep) {
 	newChangeDet();
    }
-    virtual void visit(AstPackArrayDType* nodep, AstNUser*) {
+    virtual void visit(AstPackArrayDType* nodep) {
 	newChangeDet();
    }
-    virtual void visit(AstUnpackArrayDType* nodep, AstNUser*) {
+    virtual void visit(AstUnpackArrayDType* nodep) {
 	for (int index=0; index < nodep->elementsConst(); ++index) {
 	    AstNode* origVEp = m_varEqnp;
 	    AstNode* origNLEp = m_newLvEqnp;
@@ -124,7 +170,7 @@ private:
 	    m_newRvEqnp = origNREp;
 	}
    }
-    virtual void visit(AstNodeClassDType* nodep, AstNUser*) {
+    virtual void visit(AstNodeClassDType* nodep) {
 	if (nodep->packedUnsup()) {
 	    newChangeDet();
 	} else {
@@ -132,7 +178,7 @@ private:
 	    m_vscp->v3warn(E_DETECTARRAY, "Unsupported: Can't detect changes on complex variable (probably with UNOPTFLAT warning suppressed): "<<m_vscp->varp()->prettyName());
 	}
    }
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
 	if (debug()) nodep->dumpTree(cout,"-DETECTARRAY-general-");
 	m_vscp->v3warn(E_DETECTARRAY, "Unsupported: Can't detect changes on complex variable (probably with UNOPTFLAT warning suppressed): "<<m_vscp->varp()->prettyName());
@@ -193,14 +239,15 @@ private:
    }

    // VISITORS
-    virtual void visit(AstNodeModule* nodep, AstNUser*) {
+    virtual void visit(AstNodeModule* nodep) {
 	UINFO(4," MOD   "<<nodep<<endl);
 	if (nodep->isTop()) {
 	    m_statep->m_topModp = nodep;
 	}
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstTopScope* nodep, AstNUser*) {
+
+    virtual void visit(AstTopScope* nodep) {
 	UINFO(4," TS "<<nodep<<endl);
 	// Clearing
 	AstNode::user1ClearTree();
@@ -208,18 +255,21 @@ private:
 	AstScope* scopep = nodep->scopep();
 	if (!scopep) nodep->v3fatalSrc("No scope found on top level, perhaps you have no statements?\n");
 	m_statep->m_scopetopp = scopep;
-	// Create change detection function
-	m_statep->m_chgFuncp = new AstCFunc(nodep->fileline(), "_change_request", scopep, "QData");
-	m_statep->m_chgFuncp->argTypes(EmitCBaseVisitor::symClassVar());
-	m_statep->m_chgFuncp->symProlog(true);
-	m_statep->m_chgFuncp->declPrivate(true);
-	m_statep->m_scopetopp->addActivep(m_statep->m_chgFuncp);
-	// We need at least one change detect so we know to emit the correct code
+
+	// Create a wrapper change detection function that calls each change detection function
+	m_statep->m_tlChgFuncp = new AstCFunc(nodep->fileline(), "_change_request", scopep, "QData");
+	m_statep->m_tlChgFuncp->argTypes(EmitCBaseVisitor::symClassVar());
+	m_statep->m_tlChgFuncp->symProlog(true);
+	m_statep->m_tlChgFuncp->declPrivate(true);
+	m_statep->m_scopetopp->addActivep(m_statep->m_tlChgFuncp);
+	// Each change detection function needs at least one AstChangeDet
+	// to ensure that V3EmitC outputs the necessary code.
+	m_statep->maybeCreateChgFuncp();
 	m_statep->m_chgFuncp->addStmtsp(new AstChangeDet(nodep->fileline(), NULL, NULL, false));
-	//
+
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstVarScope* nodep, AstNUser*) {
+    virtual void visit(AstVarScope* nodep) {
 	if (nodep->isCircular()) {
 	    UINFO(8,"  CIRC "<<nodep<<endl);
 	    if (!nodep->user1SetOnce()) {
@@ -227,12 +277,12 @@ private:
 	    }
 	}
    }
-    virtual void visit(AstNodeMath* nodep, AstNUser*) {
+    virtual void visit(AstNodeMath* nodep) {
 	// Short-circuit 
    }
    //--------------------
    // Default: Just iterate
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }

@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -78,7 +78,7 @@ private:
 	if (old_dtypep->width() != width) {
 	    // Since any given dtype's cppWidth() is the same, we can just
 	    // remember one convertion for each, and reuse it
-	    if (AstNodeDType* new_dtypep = old_dtypep->user3p()->castNode()->castNodeDType()) {
+	    if (AstNodeDType* new_dtypep = old_dtypep->user3p()->castNodeDType()) {
 		nodep->dtypep(new_dtypep);
 	    } else {
 		nodep->dtypeChgWidth(width, nodep->widthMin());
@@ -173,12 +173,12 @@ private:
    }

    // VISITORS
-    virtual void visit(AstNodeModule* nodep, AstNUser*) {
+    virtual void visit(AstNodeModule* nodep) {
 	m_modp = nodep;
 	nodep->iterateChildren(*this);
 	m_modp = NULL;
    }
-    virtual void visit(AstNodeUniop* nodep, AstNUser*) {
+    virtual void visit(AstNodeUniop* nodep) {
 	nodep->iterateChildren(*this);
 	computeCppWidth(nodep);
 	if (nodep->cleanLhs()) {
@@ -186,45 +186,45 @@ private:
 	}
 	setClean (nodep, nodep->cleanOut());
    }
-    virtual void visit(AstNodeBiop* nodep, AstNUser*) {
+    virtual void visit(AstNodeBiop* nodep) {
 	operandBiop(nodep);
 	setClean (nodep, nodep->cleanOut());
    }
-    virtual void visit(AstAnd* nodep, AstNUser*) {
+    virtual void visit(AstAnd* nodep) {
 	operandBiop(nodep);
 	setClean (nodep, isClean(nodep->lhsp()) || isClean(nodep->rhsp()));
    }
-    virtual void visit(AstXor* nodep, AstNUser*) {
+    virtual void visit(AstXor* nodep) {
 	operandBiop(nodep);
 	setClean (nodep, isClean(nodep->lhsp()) && isClean(nodep->rhsp()));
    }
-    virtual void visit(AstOr* nodep, AstNUser*) {
+    virtual void visit(AstOr* nodep) {
 	operandBiop(nodep);
 	setClean (nodep, isClean(nodep->lhsp()) && isClean(nodep->rhsp()));
    }
-    virtual void visit(AstNodeMath* nodep, AstNUser*) {
+    virtual void visit(AstNodeMath* nodep) {
 	nodep->iterateChildren(*this);
 	computeCppWidth(nodep);
        setClean (nodep, nodep->cleanOut());
    }
-    virtual void visit(AstNodeAssign* nodep, AstNUser*) {
+    virtual void visit(AstNodeAssign* nodep) {
 	nodep->iterateChildren(*this);
 	computeCppWidth(nodep);
 	if (nodep->cleanRhs()) {
 	    insureClean(nodep->rhsp());
 	}
    }
-    virtual void visit(AstText* nodep, AstNUser*) {
+    virtual void visit(AstText* nodep) {
 	setClean (nodep, true);
    }
-    virtual void visit(AstScopeName* nodep, AstNUser*) {
+    virtual void visit(AstScopeName* nodep) {
 	setClean (nodep, true);
    }
-    virtual void visit(AstSel* nodep, AstNUser*) {
+    virtual void visit(AstSel* nodep) {
 	operandTriop(nodep);
        setClean (nodep, nodep->cleanOut());
    }
-    virtual void visit(AstUCFunc* nodep, AstNUser*) {
+    virtual void visit(AstUCFunc* nodep) {
 	nodep->iterateChildren(*this);
 	computeCppWidth(nodep);
        setClean (nodep, false);
@@ -234,53 +234,58 @@ private:
 	}
 	insureCleanAndNext (nodep->bodysp());
    }
-    virtual void visit(AstTraceInc* nodep, AstNUser*) {
+    virtual void visit(AstTraceInc* nodep) {
 	nodep->iterateChildren(*this);
 	insureCleanAndNext (nodep->valuep());
    }
-    virtual void visit(AstTypedef* nodep, AstNUser*) {
+    virtual void visit(AstTypedef* nodep) {
+	// No cleaning, or would loose pointer to enum
+	nodep->iterateChildren(*this);
+    }
+    virtual void visit(AstParamTypeDType* nodep) {
 	// No cleaning, or would loose pointer to enum
 	nodep->iterateChildren(*this);
    }

    // Control flow operators
-    virtual void visit(AstNodeCond* nodep, AstNUser*) {
+    virtual void visit(AstNodeCond* nodep) {
 	nodep->iterateChildren(*this);
 	insureClean(nodep->condp());
 	setClean(nodep, isClean(nodep->expr1p()) && isClean(nodep->expr2p()));
    }
-    virtual void visit(AstWhile* nodep, AstNUser*) {
+    virtual void visit(AstWhile* nodep) {
 	nodep->iterateChildren(*this);
 	insureClean(nodep->condp());
    }
-    virtual void visit(AstNodeIf* nodep, AstNUser*) {
+    virtual void visit(AstNodeIf* nodep) {
 	nodep->iterateChildren(*this);
 	insureClean(nodep->condp());
    }
-    virtual void visit(AstSFormatF* nodep, AstNUser*) {
+    virtual void visit(AstSFormatF* nodep) {
 	nodep->iterateChildren(*this);
 	insureCleanAndNext (nodep->exprsp());
 	setClean(nodep, true);  // generates a string, so not relevant
    }
-    virtual void visit(AstUCStmt* nodep, AstNUser*) {
+    virtual void visit(AstUCStmt* nodep) {
 	nodep->iterateChildren(*this);
 	insureCleanAndNext (nodep->bodysp());
    }
-    virtual void visit(AstCCall* nodep, AstNUser*) {
+    virtual void visit(AstCCall* nodep) {
 	nodep->iterateChildren(*this);
 	insureCleanAndNext (nodep->argsp());
+	setClean (nodep, true);
    }

    //--------------------
    // Default: Just iterate
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
 	computeCppWidth(nodep);
    }

 public:
    // CONSTUCTORS
-    CleanVisitor(AstNetlist* nodep) {
+    explicit CleanVisitor(AstNetlist* nodep) {
 	nodep->accept(*this);
    }
    virtual ~CleanVisitor() {}
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2008-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2008-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -66,7 +66,7 @@ class GaterVarVertex;
 class GaterVertex : public V3GraphVertex {
    static uint32_t s_rankNum;
 public:
-    GaterVertex(V3Graph* graphp)
+    explicit GaterVertex(V3Graph* graphp)
 	: V3GraphVertex(graphp) {
 	s_rankNum++; rank(s_rankNum);
    }
@@ -79,7 +79,7 @@ uint32_t GaterVertex::s_rankNum = 0;

 class GaterHeadVertex : public GaterVertex {
 public:
-    GaterHeadVertex(V3Graph* graphp)
+    explicit GaterHeadVertex(V3Graph* graphp)
 	: GaterVertex(graphp) {}
    virtual ~GaterHeadVertex() {}
    virtual int typeNum() const { return __LINE__; }  // C++ typeof() equivelent
@@ -89,7 +89,7 @@ public:

 class GaterPliVertex : public GaterVertex {
 public:
-    GaterPliVertex(V3Graph* graphp)
+    explicit GaterPliVertex(V3Graph* graphp)
 	: GaterVertex(graphp) {}
    virtual ~GaterPliVertex() {}
    virtual int typeNum() const { return __LINE__; }  // C++ typeof() equivelent
@@ -199,25 +199,25 @@ private:
 	if (m_isSimple) nodep->iterateChildren(*this);
    }
    // VISITORS
-    virtual void visit(AstOr* nodep, AstNUser*) {	okIterate(nodep); }
-    virtual void visit(AstAnd* nodep, AstNUser*) {	okIterate(nodep); }
-    virtual void visit(AstNot* nodep, AstNUser*) {	okIterate(nodep); }
-    virtual void visit(AstLogOr* nodep, AstNUser*) {	okIterate(nodep); }
-    virtual void visit(AstLogAnd* nodep, AstNUser*) {	okIterate(nodep); }
-    virtual void visit(AstLogNot* nodep, AstNUser*) {	okIterate(nodep); }
-    virtual void visit(AstVarRef* nodep, AstNUser*) {	okIterate(nodep); }
+    virtual void visit(AstOr* nodep) {	okIterate(nodep); }
+    virtual void visit(AstAnd* nodep) {	okIterate(nodep); }
+    virtual void visit(AstNot* nodep) {	okIterate(nodep); }
+    virtual void visit(AstLogOr* nodep) {	okIterate(nodep); }
+    virtual void visit(AstLogAnd* nodep) {	okIterate(nodep); }
+    virtual void visit(AstLogNot* nodep) {	okIterate(nodep); }
+    virtual void visit(AstVarRef* nodep) {	okIterate(nodep); }

    // Other possibilities are equals, etc
    // But, we don't want to get too complicated or it will take too much
    // effort to calculate the gater

-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	m_isSimple = false;
 	//nodep->iterateChildren(*this);
    }
 public:
    // CONSTUCTORS
-    GaterCondVisitor(AstNode* nodep) {
+    explicit GaterCondVisitor(AstNode* nodep) {
 	m_isSimple = true;
 	nodep->accept(*this);
    }
@@ -248,10 +248,10 @@ class GaterBodyVisitor : public GaterBaseVisitor {
    uint32_t	m_state;	// Parsing state

    // VISITORS
-    virtual void visit(AstVarRef* nodep, AstNUser*) {
+    virtual void visit(AstVarRef* nodep) {
 	if (nodep->lvalue()) {
 	    AstVarScope* vscp = nodep->varScopep();
-	    if (vscp->user2p()->castNode() == m_exprp) {
+	    if (vscp->user2p() == m_exprp) {
 		// This variable's block needs to move to the new always
 		if (m_original) {
 		    UINFO(9,"  VARREF delete in old: "<<nodep<<endl);
@@ -272,11 +272,11 @@ class GaterBodyVisitor : public GaterBaseVisitor {
 	}
    }

-    //virtual void visit(AstNodeIf* nodep, AstNUser*) { ... }
+    //virtual void visit(AstNodeIf* nodep) { ... }
    // Not needed, it's the same handling as any other statement.  Cool, huh?
    // (We may get empty IFs but the constant propagater will rip them up for us)

-    virtual void visit(AstNodeStmt* nodep, AstNUser*) {
+    virtual void visit(AstNodeStmt* nodep) {
 	uint32_t oldstate = m_state;
 	// Find if children want to delete this or not.
 	// Note children may bicker, and want to both keep and delete (branches on a if)
@@ -296,7 +296,7 @@ class GaterBodyVisitor : public GaterBaseVisitor {
 	}

 	if ((childstate & STATE_DELETE) && !(childstate & STATE_KEEP)) {
-	    nodep->unlinkFrBack()->deleteTree(); nodep=NULL;
+	    nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
 	    // Pass upwards we did delete
 	    m_state |= STATE_DELETE;
 	} else {
@@ -304,7 +304,7 @@ class GaterBodyVisitor : public GaterBaseVisitor {
 	    m_state |= STATE_KEEP;
 	}
    }
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }
 public:
@@ -427,7 +427,7 @@ class GaterVisitor : public GaterBaseVisitor {
 	    for (V3GraphEdge* nextp,* edgep = m_pliVertexp->outBeginp(); edgep; edgep = nextp) {
 		nextp = edgep->outNextp();  // We may edit the list
 		if (GaterVarVertex* vVxp = dynamic_cast<GaterVarVertex*>(edgep->top())) {
-		    vVxp->unlinkDelete(&m_graph); vVxp=NULL; edgep=NULL;
+		    vVxp->unlinkDelete(&m_graph); VL_DANGLING(vVxp); VL_DANGLING(edgep);
 		} else {
 		    m_graph.dump();
 		    v3fatalSrc("PLI vertex points to non-signal");
@@ -463,7 +463,7 @@ class GaterVisitor : public GaterBaseVisitor {
 		V3GraphVertex* toVxp = edgep->top();
 		//UINFO(9," to "<<toVxp->user()<<" "<<toVxp<<endl);
 		if ((toVxp->user() & VU_IF) && (toVxp->user() & VU_ELSE)) {
-		    edgep->unlinkDelete(); edgep = NULL;
+		    edgep->unlinkDelete(); VL_DANGLING(edgep);
 		    if (!(toVxp->user() & VU_MADE)) {   // Make an edge only once
 			toVxp->user(toVxp->user() | VU_MADE);
 			GaterEdge* inedgep = static_cast<GaterEdge*>(vertexp->inBeginp());
@@ -487,7 +487,7 @@ class GaterVisitor : public GaterBaseVisitor {
 		if (toVxp->user() && toVxp->user() < depth) {
 		    // A recursion "above" us marked it,
 		    // Remove this edge, it's redundant with the upper edge
-		    edgep->unlinkDelete(); edgep=NULL;
+		    edgep->unlinkDelete(); VL_DANGLING(edgep);
 		} else {
 		    GaterEdge* cedgep = static_cast<GaterEdge*>(edgep);
 		    if (cedgep->ifelseBoth()) {
@@ -515,7 +515,7 @@ class GaterVisitor : public GaterBaseVisitor {
 	    if (GaterIfVertex* toVxp = dynamic_cast<GaterIfVertex*>(edgep->top())) {
 		if (!toVxp->outBeginp()) {
 		    if (!nextp || nextp->top() != edgep->top()) {  // Else next would disappear; we'll do it next loop
-			toVxp->unlinkDelete(&m_graph); toVxp=NULL; edgep=NULL;
+			toVxp->unlinkDelete(&m_graph); VL_DANGLING(toVxp); VL_DANGLING(edgep);
 		    }
 		}
 	    }
@@ -529,7 +529,7 @@ class GaterVisitor : public GaterBaseVisitor {
 	    nextp = edgep->outNextp();  // We may edit the list
 	    if (GaterVarVertex* toVxp = dynamic_cast<GaterVarVertex*>(edgep->top())) {
 		if (!nextp || nextp->top() != edgep->top()) {  // Else next would disappear; we'll do it next loop
-		    toVxp->unlinkDelete(&m_graph); toVxp=NULL; edgep=NULL;
+		    toVxp->unlinkDelete(&m_graph); VL_DANGLING(toVxp); VL_DANGLING(edgep);
 		}
 	    }
 	}
@@ -701,7 +701,7 @@ class GaterVisitor : public GaterBaseVisitor {
    }

    // VISITORS
-    virtual void visit(AstAlways* nodep, AstNUser*) {
+    virtual void visit(AstAlways* nodep) {
 	if (debug()>=9) cout<<endl<<endl<<endl;
 	UINFO(5, "Gater: ALWAYS: "<<nodep<<endl);
 	if (nodep->user4SetOnce()) return;
@@ -751,7 +751,7 @@ class GaterVisitor : public GaterBaseVisitor {
 	}
 	UINFO(5, "  Gater done"<<endl);
    }
-    virtual void visit(AstVarRef* nodep, AstNUser*) {
+    virtual void visit(AstVarRef* nodep) {
 	if (nodep->lvalue()) {
 	    AstVarScope* vscp = nodep->varScopep();
 	    if (nodep->varp()->isSigPublic()) {
@@ -778,7 +778,7 @@ class GaterVisitor : public GaterBaseVisitor {
 	    }
 	}
    }
-    virtual void visit(AstNodeIf* nodep, AstNUser*) {
+    virtual void visit(AstNodeIf* nodep) {
 	m_ifDepth++;
 	bool allowGater = m_directlyUnderAlw && m_ifDepth <= IF_DEPTH_MAX;
 	if (allowGater) {
@@ -819,12 +819,12 @@ class GaterVisitor : public GaterBaseVisitor {
 	m_ifDepth--;
    }

-    virtual void visit(AstAssignDly* nodep, AstNUser*) {
+    virtual void visit(AstAssignDly* nodep) {
 	// iterateChildrenAlw will detect this is a statement for us
 	iterateChildrenAlw(nodep, false);
    }

-    virtual void visit(AstNodeAssign* nodep, AstNUser*) {
+    virtual void visit(AstNodeAssign* nodep) {
 	// Note NOT AssignDly; handled above, We'll just mark this block as
 	// not optimizable.
 	//
@@ -836,7 +836,7 @@ class GaterVisitor : public GaterBaseVisitor {
 	// No reason to iterate.
    }

-    virtual void visit(AstSenItem* nodep, AstNUser*) {
+    virtual void visit(AstSenItem* nodep) {
 	if (!nodep->isClocked()) {
 	    nonOptimizable(nodep, "Non-clocked sensitivity");
 	}
@@ -844,7 +844,7 @@ class GaterVisitor : public GaterBaseVisitor {
    }

    //--------------------
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	if (m_nonopt=="") {  // Else accelerate
 	    iterateChildrenAlw(nodep, false);
 	}
@@ -878,7 +878,7 @@ class GaterVisitor : public GaterBaseVisitor {

 public:
    // CONSTUCTORS
-    GaterVisitor(AstNode* nodep) {
+    explicit GaterVisitor(AstNode* nodep) {
 	// AstAlways visitor does the real work, so most zeroing needs to be in clear()
 	clear();
 	nodep->accept(*this);
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -108,6 +108,12 @@ private:
 	// HIGHEDGE:  var
 	// LOWEDGE:  ~var
 	AstNode* newp = NULL;
+	if (nodep->edgeType()==AstEdgeType::ET_ILLEGAL) {
+	    if (!v3Global.opt.bboxUnsup()) {
+		nodep->v3error("Unsupported: Complicated event expression in sensitive activity list");
+	    }
+	    return NULL;
+	}
 	AstVarScope* clkvscp = nodep->varrefp()->varScopep();
 	if (nodep->edgeType()==AstEdgeType::ET_POSEDGE) {
 	    AstVarScope* lastVscp = getCreateLastClk(clkvscp);
@@ -182,7 +188,7 @@ private:
    }

    // VISITORS
-    virtual void visit(AstTopScope* nodep, AstNUser*) {
+    virtual void visit(AstTopScope* nodep) {
 	UINFO(4," TOPSCOPE   "<<nodep<<endl);
 	m_topScopep=nodep;
 	m_scopep = nodep->scopep();
@@ -243,14 +249,14 @@ private:
 	m_topScopep=NULL;
 	m_scopep = NULL;
    }
-    virtual void visit(AstNodeModule* nodep, AstNUser*) {
+    virtual void visit(AstNodeModule* nodep) {
 	//UINFO(4," MOD   "<<nodep<<endl);
 	m_modp = nodep;
 	m_stableNum = 0;
 	nodep->iterateChildren(*this);
 	m_modp= NULL;
    }
-    virtual void visit(AstScope* nodep, AstNUser*) {
+    virtual void visit(AstScope* nodep) {
 	//UINFO(4," SCOPE   "<<nodep<<endl);
 	m_scopep = nodep;
 	nodep->iterateChildren(*this);
@@ -261,25 +267,25 @@ private:
 	}
 	m_scopep = NULL;
    }
-    virtual void visit(AstAlways* nodep, AstNUser*) {
+    virtual void visit(AstAlways* nodep) {
 	AstNode* cmtp = new AstComment(nodep->fileline(), nodep->typeName());
 	nodep->replaceWith(cmtp);
 	if (AstNode* stmtsp = nodep->bodysp()) {
 	    stmtsp->unlinkFrBackWithNext();
 	    cmtp->addNextHere(stmtsp);
 	}
-	nodep->deleteTree(); nodep = NULL;
+	nodep->deleteTree(); VL_DANGLING(nodep);
    }
-    virtual void visit(AstAlwaysPost* nodep, AstNUser*) {
+    virtual void visit(AstAlwaysPost* nodep) {
 	AstNode* cmtp = new AstComment(nodep->fileline(), nodep->typeName());
 	nodep->replaceWith(cmtp);
 	if (AstNode* stmtsp = nodep->bodysp()) {
 	    stmtsp->unlinkFrBackWithNext();
 	    cmtp->addNextHere(stmtsp);
 	}
-	nodep->deleteTree(); nodep = NULL;
+	nodep->deleteTree(); VL_DANGLING(nodep);
    }
-    virtual void visit(AstCoverToggle* nodep, AstNUser*) {
+    virtual void visit(AstCoverToggle* nodep) {
 	//nodep->dumpTree(cout,"ct:");
 	//COVERTOGGLE(INC, ORIG, CHANGE) ->
 	//   IF(ORIG ^ CHANGE) { INC; CHANGE = ORIG; }
@@ -297,18 +303,18 @@ private:
 	newp->addIfsp(new AstAssign(nodep->fileline(),
 				    changep->cloneTree(false),
 				    origp->cloneTree(false)));
-	nodep->replaceWith(newp); nodep->deleteTree(); nodep=NULL;
+	nodep->replaceWith(newp); nodep->deleteTree(); VL_DANGLING(nodep);
    }
-    virtual void visit(AstInitial* nodep, AstNUser*) {
+    virtual void visit(AstInitial* nodep) {
 	AstNode* cmtp = new AstComment(nodep->fileline(), nodep->typeName());
 	nodep->replaceWith(cmtp);
 	if (AstNode* stmtsp = nodep->bodysp()) {
 	    stmtsp->unlinkFrBackWithNext();
 	    cmtp->addNextHere(stmtsp);
 	}
-	nodep->deleteTree(); nodep = NULL;
+	nodep->deleteTree(); VL_DANGLING(nodep);
    }
-    virtual void visit(AstCFunc* nodep, AstNUser*) {
+    virtual void visit(AstCFunc* nodep) {
 	nodep->iterateChildren(*this);
 	// Link to global function
 	if (nodep->formCallTree()) {
@@ -318,7 +324,7 @@ private:
 	    m_finalFuncp->addStmtsp(callp);
 	}
    }
-    virtual void visit(AstSenTree* nodep, AstNUser*) {
+    virtual void visit(AstSenTree* nodep) {
 	// Delete it later; Actives still pointing to it
 	nodep->unlinkFrBack();
 	pushDeletep(nodep);
@@ -335,14 +341,14 @@ private:
 	if (m_untilp) m_untilp->addBodysp(stmtsp);  // In a until loop, add to body
 	else m_initFuncp->addStmtsp(stmtsp);  // else add to top level function
    }
-    virtual void visit(AstActive* nodep, AstNUser*) {
+    virtual void visit(AstActive* nodep) {
 	// Careful if adding variables here, ACTIVES can be under other ACTIVES
 	// Need to save and restore any member state in AstUntilStable block
 	if (!m_topScopep || !nodep->stmtsp()) {
 	    // Not at the top or empty block...
 	    // Only empty blocks should be leftover on the non-top.  Killem.
 	    if (nodep->stmtsp()) nodep->v3fatalSrc("Non-empty lower active");
-	    nodep->unlinkFrBack()->deleteTree(); nodep=NULL;
+	    nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
 	} else {
 	    UINFO(4,"  ACTIVE  "<<nodep<<endl);
 	    AstNode* stmtsp = nodep->stmtsp()->unlinkFrBackWithNext();
@@ -374,19 +380,19 @@ private:
 		// Move statements to function
 		addToEvalLoop(stmtsp);
 	    }
-	    nodep->unlinkFrBack()->deleteTree(); nodep = NULL;
+	    nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
 	}
    }

    //--------------------
    // Default: Just iterate
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }

 public:
    // CONSTUCTORS
-    ClockVisitor(AstNetlist* nodep) {
+    explicit ClockVisitor(AstNetlist* nodep) {
 	m_modp=NULL; m_activep=NULL;
 	m_evalFuncp = NULL;
 	m_topScopep=NULL;
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -111,7 +111,7 @@ public:
 		    callp->unlinkFrBack();
 		}
 		callp->user3(true);	// Dead now
-		pushDeletep(callp); callp=NULL;
+		pushDeletep(callp); VL_DANGLING(callp);
 		m_callMmap.erase(eqit);	// Fix the table
 	    }
 	}
@@ -134,13 +134,13 @@ public:
    }
 private:
    // VISITORS
-    virtual void visit(AstCCall* nodep, AstNUser*) {
+    virtual void visit(AstCCall* nodep) {
 	addCall(nodep);
    }
    // Speed things up
-    virtual void visit(AstNodeAssign* nodep, AstNUser*) {}
-    virtual void visit(AstNodeMath* nodep, AstNUser*) {}
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNodeAssign* nodep) {}
+    virtual void visit(AstNodeMath* nodep) {}
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }
 public:
@@ -163,13 +163,13 @@ private:
    // OUTPUT:
    //  AstNode::user3()	-> bool. True to indicate duplicated
    // VISITORS
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->user3(true);
 	nodep->iterateChildren(*this);
    }
 public:
    // CONSTRUCTORS
-    CombMarkVisitor(AstNode* nodep) {
+    explicit CombMarkVisitor(AstNode* nodep) {
 	nodep->accept(*this);
    }
    virtual ~CombMarkVisitor() {}
@@ -230,7 +230,7 @@ private:
 		CombMarkVisitor visitor(oldfuncp);
 		m_call.replaceFunc(oldfuncp, NULL);
 		oldfuncp->unlinkFrBack();
-		pushDeletep(oldfuncp); oldfuncp=NULL;
+		pushDeletep(oldfuncp); VL_DANGLING(oldfuncp);
 	    }
 	}
    }
@@ -262,7 +262,7 @@ private:
 	CombMarkVisitor visitor(oldfuncp);
 	m_call.replaceFunc(oldfuncp, newfuncp);
 	oldfuncp->unlinkFrBack();
-	pushDeletep(oldfuncp); oldfuncp=NULL;
+	pushDeletep(oldfuncp); VL_DANGLING(oldfuncp);
    }
    void replaceOnlyCallFunc(AstCCall* nodep) {
 	if (AstCFunc* oldfuncp = nodep->backp()->castCFunc()) {
@@ -274,7 +274,7 @@ private:
 		UINFO(9,"     Function only has call "<<oldfuncp<<endl);
 		m_call.deleteCall(nodep);
 		CombMarkVisitor visitor(oldfuncp);
-		replaceFuncWFunc(oldfuncp, nodep->funcp());  nodep=NULL;
+		replaceFuncWFunc(oldfuncp, nodep->funcp()); VL_DANGLING(nodep);
 	    }
 	}
    }
@@ -384,12 +384,12 @@ private:
 	m_call.addCall(call2p);
 	// If either new statement makes a func with only a single call, replace
 	// the above callers to call it directly
-	replaceOnlyCallFunc(call1p); call1p=NULL;
-	replaceOnlyCallFunc(call2p); call2p=NULL;
+	replaceOnlyCallFunc(call1p); VL_DANGLING(call1p);
+	replaceOnlyCallFunc(call2p); VL_DANGLING(call2p);
    }

    // VISITORS
-    virtual void visit(AstNetlist* nodep, AstNUser*) {
+    virtual void visit(AstNetlist* nodep) {
 	// Track all callers of each function
 	m_call.main(nodep);
 	//
@@ -398,7 +398,7 @@ private:
 	// Required so that a module instantiating another can benefit from collapsing.
 	nodep->iterateChildrenBackwards(*this);
    }
-    virtual void visit(AstNodeModule* nodep, AstNUser*) {
+    virtual void visit(AstNodeModule* nodep) {
 	UINFO(4," MOD   "<<nodep<<endl);
 	m_modp = nodep;
 	m_modNFuncs = 0;
@@ -426,7 +426,7 @@ private:
 	}
 	m_modp = NULL;
    }
-    virtual void visit(AstCFunc* nodep, AstNUser*) {
+    virtual void visit(AstCFunc* nodep) {
 	m_funcp = nodep;
 	if (!nodep->dontCombine()) {
 	    if (m_state == STATE_HASH) {
@@ -437,7 +437,7 @@ private:
 	}
 	m_funcp = NULL;
    }
-    virtual void visit(AstNodeStmt* nodep, AstNUser*) {
+    virtual void visit(AstNodeStmt* nodep) {
 	if (m_state == STATE_HASH && m_funcp) {
 	    hashStatement(nodep);
 	}
@@ -448,16 +448,16 @@ private:

    //--------------------
    // Default: Just iterate
-    virtual void visit(AstVar*, AstNUser*) {}
-    virtual void visit(AstTraceDecl*, AstNUser*) {}
-    virtual void visit(AstTraceInc*, AstNUser*) {}
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstVar*) {}
+    virtual void visit(AstTraceDecl*) {}
+    virtual void visit(AstTraceInc*) {}
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }

 public:
    // CONSTUCTORS
-    CombineVisitor(AstNetlist* nodep) {
+    explicit CombineVisitor(AstNetlist* nodep) {
 	m_modp=NULL;
 	m_funcp = NULL;
 	m_state = STATE_IDLE;
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2010-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2010-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -144,12 +144,12 @@ V3ConfigIgnores V3ConfigIgnores::s_singleton;
 //######################################################################
 // V3Config

-void V3Config::addIgnore(V3ErrorCode code, string filename, int min, int max) {
+void V3Config::addIgnore(V3ErrorCode code, bool on, string filename, int min, int max) {
    if (filename=="*") {
-	FileLine::globalWarnOff(code,true);
+	FileLine::globalWarnOff(code,!on);
    } else {
-	V3ConfigIgnores::singleton().addIgnore(code, filename, min, false);
-	if (max) V3ConfigIgnores::singleton().addIgnore(code, filename, max, true);
+	V3ConfigIgnores::singleton().addIgnore(code, filename, min, on);
+	if (max) V3ConfigIgnores::singleton().addIgnore(code, filename, max, !on);
    }
 }

@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2010-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2010-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -30,7 +30,7 @@

 class V3Config {
 public:
-    static void addIgnore(V3ErrorCode code, string filename, int min, int max);
+    static void addIgnore(V3ErrorCode code, bool on, string filename, int min, int max);
    static void applyIgnores(FileLine* filelinep);
 };

@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -33,6 +33,7 @@
 #include <algorithm>

 #include "V3Global.h"
+#include "V3String.h"
 #include "V3Const.h"
 #include "V3Ast.h"
 #include "V3Width.h"
@@ -46,15 +47,15 @@ class ConstVarMarkVisitor : public AstNVisitor {
    // AstVar::user4p		-> bool, Var marked, 0=not set yet
 private:
    // VISITORS
-    virtual void visit(AstVarRef* nodep, AstNUser*) {
+    virtual void visit(AstVarRef* nodep) {
 	if (nodep->varp()) nodep->varp()->user4(1);
    }
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }
 public:
    // CONSTUCTORS
-    ConstVarMarkVisitor(AstNode* nodep) {
+    explicit ConstVarMarkVisitor(AstNode* nodep) {
 	AstNode::user4ClearTree();  // Check marked InUse before we're called
 	nodep->accept(*this);
    }
@@ -68,17 +69,17 @@ class ConstVarFindVisitor : public AstNVisitor {
    bool m_found;
 private:
    // VISITORS
-    virtual void visit(AstVarRef* nodep, AstNUser*) {
+    virtual void visit(AstVarRef* nodep) {
 	if (nodep->varp() && nodep->varp()->user4()) m_found = true;
    }
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }
 public:
    // CONSTUCTORS
-    ConstVarFindVisitor(AstNode* nodep) {
+    explicit ConstVarFindVisitor(AstNode* nodep) {
 	m_found = false;
-	nodep->iterateAndNext(*this, NULL);
+	nodep->iterateAndNext(*this);
    }
    virtual ~ConstVarFindVisitor() {}
    // METHODS
@@ -214,7 +215,7 @@ private:
 	if (!operandsSame(ap, bp)) return false;
 	// Do it
 	cp->unlinkFrBack();
-	andp->unlinkFrBack()->deleteTree(); andp=NULL; notp=NULL;
+	andp->unlinkFrBack()->deleteTree(); VL_DANGLING(andp); VL_DANGLING(notp);
 	// Replace whichever branch is now dangling
 	if (nodep->rhsp()) nodep->lhsp(cp);
 	else nodep->rhsp(cp);
@@ -319,7 +320,7 @@ private:
 	      && nodep->lsbConst()==0
 	      && (int)nodep->widthConst()==extendp->lhsp()->width()
 		)) return false;
-	replaceWChild(nodep, extendp->lhsp()); nodep=NULL;
+	replaceWChild(nodep, extendp->lhsp()); VL_DANGLING(nodep);
 	return true;
    }
    bool operandSelBiLower(AstSel* nodep) {
@@ -338,7 +339,7 @@ private:
 	bip->lhsp(new AstSel(nodep->fileline(), bilhsp, 0, nodep->widthConst()));
 	bip->rhsp(new AstSel(nodep->fileline(), birhsp, 0, nodep->widthConst()));
 	if (debug()>=9) bip->dumpTree(cout,"SEL(BI)-ou:");
-	replaceWChild(nodep, bip); nodep=NULL;
+	replaceWChild(nodep, bip); VL_DANGLING(nodep);
 	return true;
    }

@@ -364,7 +365,7 @@ private:
 	V3Number num (constp->fileline(), subsize);
 	num.opAssign(constp->num());
 	nodep->lhsp(new AstConst(constp->fileline(), num));
-	constp->deleteTree();  constp=NULL;
+	constp->deleteTree(); VL_DANGLING(constp);
 	if (debug()>=9) nodep->dumpTree(cout,"BI(EXTEND)-ou:");
 	return true;
    }
@@ -450,6 +451,8 @@ private:
 	if (!ifvarp || !elsevarp) return false;
 	if (ifvarp->isWide()) return false;  // Would need temporaries, so not worth it
 	if (!ifvarp->sameGateTree(elsevarp)) return false;
+	if (!ifp->rhsp()->gateTree()) return false;
+	if (!elsep->rhsp()->gateTree()) return false;
 	return true;
    }
    bool operandIfIf(AstNodeIf* nodep) {
@@ -559,58 +562,58 @@ private:
 	if (debug()>5) oldp->dumpTree(cout,"  const_old: ");
 	if (debug()>5) newp->dumpTree(cout,"       _new: ");
 	oldp->replaceWith(newp);
-	oldp->deleteTree(); oldp=NULL;
+	oldp->deleteTree(); VL_DANGLING(oldp);
    }
    void replaceNum (AstNode* nodep, uint32_t val) {
 	V3Number num (nodep->fileline(), nodep->width(), val);
-	replaceNum(nodep, num); nodep=NULL;
+	replaceNum(nodep, num); VL_DANGLING(nodep);
    }
    void replaceNumSigned(AstNodeBiop* nodep, uint32_t val) {
 	// We allow both sides to be constant, as one may have come from parameter propagation, etc.
 	if (m_warn && !(nodep->lhsp()->castConst() && nodep->rhsp()->castConst())) {
 	    nodep->v3warn(UNSIGNED,"Comparison is constant due to unsigned arithmetic");
 	}
-	replaceNum(nodep, val); nodep=NULL;
+	replaceNum(nodep, val); VL_DANGLING(nodep);
    }
    void replaceNumLimited(AstNodeBiop* nodep, uint32_t val) {
 	// Avoids gcc warning about same
 	if (m_warn) nodep->v3warn(CMPCONST,"Comparison is constant due to limited range");
-	replaceNum(nodep, val); nodep=NULL;
+	replaceNum(nodep, val); VL_DANGLING(nodep);
    }
    void replaceZero(AstNode* nodep) {
-	replaceNum(nodep, 0); nodep=NULL;
+	replaceNum(nodep, 0); VL_DANGLING(nodep);
    }
    void replaceZeroChkPure(AstNode* nodep, AstNode* checkp) {
 	// For example, "0 * n" -> 0 if n has no side effects
 	// Else strength reduce it to 0 & n.
 	// If ever change the operation note AstAnd rule specially ignores this created pattern
 	if (isTPure(checkp)) {
-	    replaceNum(nodep, 0); nodep=NULL;
+	    replaceNum(nodep, 0); VL_DANGLING(nodep);
 	} else {
 	    AstNode* newp = new AstAnd(nodep->fileline(),
 				       new AstConst(nodep->fileline(), 0),
 				       checkp->unlinkFrBack());
 	    newp->dtypeFrom(nodep);
 	    nodep->replaceWith(newp);
-	    nodep->deleteTree(); nodep=NULL;
+	    nodep->deleteTree(); VL_DANGLING(nodep);
 	}
    }
    void replaceAllOnes (AstNode* nodep) {
 	V3Number ones (nodep->fileline(), nodep->width(), 0);
 	ones.setMask(nodep->width());
-	replaceNum(nodep, ones); nodep=NULL;
+	replaceNum(nodep, ones); VL_DANGLING(nodep);
    }
    void replaceConst(AstNodeUniop* nodep) {
 	V3Number num (nodep->fileline(), nodep->width());
 	nodep->numberOperate(num, nodep->lhsp()->castConst()->num());
 	UINFO(4,"UNICONST -> "<<num<<endl);
-	replaceNum(nodep, num); nodep=NULL;
+	replaceNum(nodep, num); VL_DANGLING(nodep);
    }
    void replaceConst(AstNodeBiop* nodep) {
 	V3Number num (nodep->fileline(), nodep->width());
 	nodep->numberOperate(num, nodep->lhsp()->castConst()->num(), nodep->rhsp()->castConst()->num());
 	UINFO(4,"BICONST -> "<<num<<endl);
-	replaceNum(nodep, num); nodep=NULL;
+	replaceNum(nodep, num); VL_DANGLING(nodep);
    }
    void replaceConst(AstNodeTriop* nodep) {
 	V3Number num (nodep->fileline(), nodep->width());
@@ -618,7 +621,7 @@ private:
 			     nodep->rhsp()->castConst()->num(),
 			     nodep->thsp()->castConst()->num());
 	UINFO(4,"TRICONST -> "<<num<<endl);
-	replaceNum(nodep, num); nodep=NULL;
+	replaceNum(nodep, num); VL_DANGLING(nodep);
    }

    void replaceConstString (AstNode* oldp, const string& num) {
@@ -628,7 +631,7 @@ private:
 	if (debug()>5) oldp->dumpTree(cout,"  const_old: ");
 	if (debug()>5) newp->dumpTree(cout,"       _new: ");
 	oldp->replaceWith(newp);
-	oldp->deleteTree(); oldp=NULL;
+	oldp->deleteTree(); VL_DANGLING(oldp);
    }
    //----------------------------------------
    // Replacement functions.
@@ -641,7 +644,7 @@ private:
 	// This may adversly affect the operation of the node being replaced.
 	childp->dtypeFrom(nodep);
 	nodep->replaceWith(childp);
-	nodep->deleteTree(); nodep=NULL;
+	nodep->deleteTree(); VL_DANGLING(nodep);
    }

    //! Replace a ternary node with its RHS after iterating
@@ -775,9 +778,9 @@ private:
 	UINFO(5, "merged two adjacent sel "<<lselp <<" and "<<rselp<< " to one "<<newselp<<endl);

 	nodep->replaceWith(newselp);
-	lselp->deleteTree(); lselp = NULL;
-	rselp->deleteTree(); rselp = NULL;
-	nodep->deleteTree(); nodep = NULL;
+	lselp->deleteTree(); VL_DANGLING(lselp);
+	rselp->deleteTree(); VL_DANGLING(rselp);
+	nodep->deleteTree(); VL_DANGLING(nodep);
    }
    void replaceConcatMerge(AstConcat* nodep) {
 	AstNodeBiop* lp = nodep->lhsp()->castNodeBiop();
@@ -794,8 +797,8 @@ private:
 	    lp->rhsp()->replaceWith(newrp);
 	    lp->dtypeChgWidthSigned(newlp->width(), newlp->width(), AstNumeric::fromBool(true));
 	    UINFO(5, "merged "<< nodep <<endl);
-	    rp->unlinkFrBack()->deleteTree(); rp = NULL;
-	    nodep->replaceWith(lp->unlinkFrBack()); nodep->deleteTree(); nodep = NULL;
+	    rp->unlinkFrBack()->deleteTree(); VL_DANGLING(rp);
+	    nodep->replaceWith(lp->unlinkFrBack()); nodep->deleteTree(); VL_DANGLING(nodep);
 	    lp->lhsp()->accept(*this);
 	    lp->rhsp()->accept(*this);
 	} else nodep->v3fatalSrc("tried to merge two Concat which are not adjacent");
@@ -805,10 +808,10 @@ private:
 	// like a AstExtend{$rhsp}, but we need to set the width correctly from base node
 	arg0p->unlinkFrBack();
 	AstNode* newp = (nodep->castExtendS()
-			 ? (new AstExtendS(nodep->fileline(), arg0p))->castNode()
-			 : (new AstExtend (nodep->fileline(), arg0p))->castNode());
+			 ? static_cast<AstNode*>(new AstExtendS(nodep->fileline(), arg0p))
+			 : static_cast<AstNode*>(new AstExtend (nodep->fileline(), arg0p)));
 	newp->dtypeFrom(nodep);
-	nodep->replaceWith(newp); nodep->deleteTree(); nodep=NULL;
+	nodep->replaceWith(newp); nodep->deleteTree(); VL_DANGLING(nodep);
    }
    void replacePowShift (AstNodeBiop* nodep) {  // Pow or PowS
 	UINFO(5,"POW(2,b)->SHIFTL(1,b) "<<nodep<<endl);
@@ -818,7 +821,7 @@ private:
 					rhsp);
 	newp->dtypeFrom(nodep);
 	newp->lhsp()->dtypeFrom(nodep);
-	nodep->replaceWith(newp); nodep->deleteTree(); nodep=NULL;
+	nodep->replaceWith(newp); nodep->deleteTree(); VL_DANGLING(nodep);
    }
    void replaceMulShift (AstMul* nodep) {  // Mul, but not MulS as not simple shift
 	UINFO(5,"MUL(2^n,b)->SHIFTL(b,n) "<<nodep<<endl);
@@ -827,7 +830,7 @@ private:
 	AstShiftL* newp = new AstShiftL(nodep->fileline(),
 					opp, new AstConst(nodep->fileline(), amount));
 	newp->dtypeFrom(nodep);
-	nodep->replaceWith(newp); nodep->deleteTree(); nodep=NULL;
+	nodep->replaceWith(newp); nodep->deleteTree(); VL_DANGLING(nodep);
    }
    void replaceDivShift (AstDiv* nodep) {  // Mul, but not MulS as not simple shift
 	UINFO(5,"DIV(b,2^n)->SHIFTR(b,n) "<<nodep<<endl);
@@ -836,7 +839,7 @@ private:
 	AstShiftR* newp = new AstShiftR(nodep->fileline(),
 					opp, new AstConst(nodep->fileline(), amount));
 	newp->dtypeFrom(nodep);
-	nodep->replaceWith(newp); nodep->deleteTree(); nodep=NULL;
+	nodep->replaceWith(newp); nodep->deleteTree(); VL_DANGLING(nodep);
    }
    void replaceShiftOp (AstNodeBiop* nodep) {
 	UINFO(5,"SHIFT(AND(a,b),CONST)->AND(SHIFT(a,CONST),SHIFT(b,CONST)) "<<nodep<<endl);
@@ -867,8 +870,8 @@ private:
 	    int shift1 = shift1p->castConst()->toUInt();
 	    int shift2 = shift2p->castConst()->toUInt();
 	    int newshift = shift1+shift2;
-	    shift1p->deleteTree(); shift1p=NULL;
-	    shift2p->deleteTree(); shift2p=NULL;
+	    shift1p->deleteTree(); VL_DANGLING(shift1p);
+	    shift2p->deleteTree(); VL_DANGLING(shift2p);
 	    nodep->lhsp(ap);
 	    nodep->rhsp(new AstConst(nodep->fileline(), newshift));
 	    nodep->accept(*this);	// Further reduce, either node may have more reductions.
@@ -877,8 +880,8 @@ private:
 	    int shift1 = shift1p->castConst()->toUInt(); if (lhsp->castShiftR())  shift1=-shift1;
 	    int shift2 = shift2p->castConst()->toUInt(); if (nodep->castShiftR()) shift2=-shift2;
 	    int newshift = shift1+shift2;
-	    shift1p->deleteTree(); shift1p=NULL;
-	    shift2p->deleteTree(); shift2p=NULL;
+	    shift1p->deleteTree(); VL_DANGLING(shift1p);
+	    shift2p->deleteTree(); VL_DANGLING(shift2p);
 	    AstNode* newp;
 	    V3Number mask1 (nodep->fileline(), nodep->width());
 	    V3Number ones (nodep->fileline(), nodep->width());
@@ -906,11 +909,11 @@ private:
 			       newp,
 			       new AstConst (nodep->fileline(), mask));
 	    newp->dtypeFrom(nodep);
-	    nodep->replaceWith(newp); nodep->deleteTree(); nodep=NULL;
+	    nodep->replaceWith(newp); nodep->deleteTree(); VL_DANGLING(nodep);
 	    //newp->dumpTree(cout, "  repShiftShift_new: ");
 	    newp->accept(*this);	// Further reduce, either node may have more reductions.
 	}
-	lhsp->deleteTree(); lhsp=NULL;
+	lhsp->deleteTree(); VL_DANGLING(lhsp);
    }

    bool replaceAssignMultiSel(AstNodeAssign* nodep) {
@@ -983,7 +986,7 @@ private:
 		nodep->v3error("Wire inputs its own output, creating circular logic (wire x=x)");
 		return false;  // Don't delete the assign, or V3Gate will freak out
 	    } else {
-		nodep->unlinkFrBack()->deleteTree(); nodep=NULL;
+		nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
 		return true;
 	    }
 	}
@@ -1034,10 +1037,8 @@ private:
 		AstNodeAssign* asn2ap=nodep->cloneType(lc2p, sel2p)->castNodeAssign();
 		asn1ap->dtypeFrom(sel1p);
 		asn2ap->dtypeFrom(sel2p);
-		// cppcheck-suppress nullPointer  // addNext deals with it
-		newp = newp->addNext(asn1ap);
-		// cppcheck-suppress nullPointer  // addNext deals with it
-		newp = newp->addNext(asn2ap);
+		newp = AstNode::addNext(newp, asn1ap);
+		newp = AstNode::addNext(newp, asn2ap);
 	    } else {
 		if (!m_modp) nodep->v3fatalSrc("Not under module");
 		// We could create just one temp variable, but we'll get better optimization
@@ -1067,20 +1068,16 @@ private:
 		asn2ap->dtypeFrom(temp2p);
 		asn2bp->dtypeFrom(temp2p);
 		// This order matters
-		// cppcheck-suppress nullPointer  // addNext deals with it
-		newp = newp->addNext(asn1ap);
-		// cppcheck-suppress nullPointer  // addNext deals with it
-		newp = newp->addNext(asn2ap);
-		// cppcheck-suppress nullPointer  // addNext deals with it
-		newp = newp->addNext(asn1bp);
-		// cppcheck-suppress nullPointer  // addNext deals with it
-		newp = newp->addNext(asn2bp);
+		newp = AstNode::addNext(newp, asn1ap);
+		newp = AstNode::addNext(newp, asn2ap);
+		newp = AstNode::addNext(newp, asn1bp);
+		newp = AstNode::addNext(newp, asn2bp);
 	    }
 	    if (debug()>=9 && newp) newp->dumpTreeAndNext(cout,"     _new: ");
 	    nodep->addNextHere(newp);
 	    // Cleanup
-	    nodep->unlinkFrBack()->deleteTree(); nodep=NULL;
-	    conp->deleteTree(); conp=NULL;
+	    nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
+	    conp->deleteTree(); VL_DANGLING(conp);
 	    // Further reduce, either node may have more reductions.
 	    return true;
 	}
@@ -1093,8 +1090,8 @@ private:
 	    AstNode* streamp = nodep->rhsp()->castStreamR()->unlinkFrBack();
 	    nodep->rhsp(srcp);
 	    // Cleanup
-	    sizep->deleteTree(); sizep=NULL;
-	    streamp->deleteTree(); streamp=NULL;
+	    sizep->deleteTree(); VL_DANGLING(sizep);
+	    streamp->deleteTree(); VL_DANGLING(streamp);
 	    // Further reduce, any of the nodes may have more reductions.
 	    return true;
 	}
@@ -1137,8 +1134,8 @@ private:
 	    nodep->lhsp(dstp);
 	    nodep->rhsp(srcp);
 	    // Cleanup
-	    sizep->deleteTree(); sizep=NULL;
-	    streamp->deleteTree(); streamp=NULL;
+	    sizep->deleteTree(); VL_DANGLING(sizep);
+	    streamp->deleteTree(); VL_DANGLING(streamp);
 	    // Further reduce, any of the nodes may have more reductions.
 	    return true;
 	}
@@ -1171,7 +1168,7 @@ private:
 				  fromp);
 	newp->dtypeSetLogicSized(nodep->width(), nodep->width(), AstNumeric::UNSIGNED);  // widthMin no longer applicable if different C-expanded width
 	nodep->replaceWith(newp);
-	nodep->deleteTree(); nodep=NULL;
+	nodep->deleteTree(); VL_DANGLING(nodep);
 	if (debug()>=9) newp->dumpTree(cout,"       _new: ");
    }

@@ -1185,36 +1182,36 @@ private:
 			   <<nodep->prettyTypeName()<<endl
 			   <<errorp->warnMore()<<"... Location of non-constant "
 			   <<errorp->prettyTypeName()<<": "<<simvis.whyNotMessage());
-	    replaceZero(nodep); nodep=NULL;
+	    replaceZero(nodep); VL_DANGLING(nodep);
 	} else {
 	    // Fetch the result
 	    V3Number* outnump = simvis.fetchNumberNull(nodep);
 	    if (!outnump) nodep->v3fatalSrc("No number returned from simulation");
 	    // Replace it
-	    replaceNum(nodep,*outnump); nodep=NULL;
+	    replaceNum(nodep,*outnump); VL_DANGLING(nodep);
 	}
    }

    //----------------------------------------

    // VISITORS
-    virtual void visit(AstNetlist* nodep, AstNUser*) {
+    virtual void visit(AstNetlist* nodep) {
 	// Iterate modules backwards, in bottom-up order.  That's faster
 	nodep->iterateChildrenBackwards(*this);
    }
-    virtual void visit(AstNodeModule* nodep, AstNUser*) {
+    virtual void visit(AstNodeModule* nodep) {
 	m_modp = nodep;
 	nodep->iterateChildren(*this);
 	m_modp = NULL;
    }
-    virtual void visit(AstCFunc* nodep, AstNUser*) {
+    virtual void visit(AstCFunc* nodep) {
 	// No ASSIGNW removals under funcs, we've long eliminated INITIALs
 	// (We should perhaps rename the assignw's to just assigns)
 	m_wremove = false;
 	nodep->iterateChildren(*this);
 	m_wremove = true;
    }
-    virtual void visit(AstScope* nodep, AstNUser*) {
+    virtual void visit(AstScope* nodep) {
 	// No ASSIGNW removals under scope, we've long eliminated INITIALs
 	m_scopep = nodep;
 	m_wremove = false;
@@ -1271,7 +1268,7 @@ private:
 	    // If bp was a concat, then we have this exact same form again!
 	    // Recurse rather then calling node->iterate to prevent 2^n recursion!
 	    if (operandConcatMove(abConcp)) moveConcat(abConcp);
-	    bcConcp->deleteTree(); bcConcp=NULL;
+	    bcConcp->deleteTree(); VL_DANGLING(bcConcp);
 	} else {
 	    AstConcat* abConcp = nodep->lhsp()->castConcat(); abConcp->unlinkFrBack();
 	    AstNode* ap = abConcp->lhsp()->unlinkFrBack();
@@ -1282,21 +1279,21 @@ private:
 	    nodep->lhsp(ap);
 	    nodep->rhsp(bcConcp);
 	    if (operandConcatMove(bcConcp)) moveConcat(bcConcp);
-	    abConcp->deleteTree(); abConcp=NULL;
+	    abConcp->deleteTree(); VL_DANGLING(abConcp);
 	}
    }

    // Special cases
-    virtual void visit(AstConst* nodep, AstNUser*) {}	// Already constant
+    virtual void visit(AstConst* nodep) {}	// Already constant

-    virtual void visit(AstCell* nodep, AstNUser*) {
+    virtual void visit(AstCell* nodep) {
 	if (m_params) {
 	    nodep->paramsp()->iterateAndNext(*this);
 	} else {
 	    nodep->iterateChildren(*this);
 	}
    }
-    virtual void visit(AstPin* nodep, AstNUser*) {
+    virtual void visit(AstPin* nodep) {
 	nodep->iterateChildren(*this);
    }

@@ -1313,8 +1310,8 @@ private:
 	if (lsb1p->castConst() && lsb2p->castConst()) {
 	    newlsbp = new AstConst(lsb1p->fileline(),
 				   lsb1p->castConst()->toUInt() + lsb2p->castConst()->toUInt());
-	    lsb1p->deleteTree(); lsb1p=NULL;
-	    lsb2p->deleteTree(); lsb2p=NULL;
+	    lsb1p->deleteTree(); VL_DANGLING(lsb1p);
+	    lsb2p->deleteTree(); VL_DANGLING(lsb2p);
 	} else {
 	    // Width is important, we need the width of the fromp's
 	    // expression, not the potentially smaller lsb1p's width
@@ -1328,7 +1325,7 @@ private:
 				  newlsbp,
 				  widthp);
 	nodep->replaceWith(newp);
-	nodep->deleteTree(); nodep=NULL;
+	nodep->deleteTree(); VL_DANGLING(nodep);
    }

    void replaceSelConcat(AstSel* nodep) {
@@ -1368,7 +1365,7 @@ private:
 			    conRhsp->width()-nodep->lsbConst()));
 	    nodep->replaceWith(newp);
 	}
-	nodep->deleteTree(); nodep=NULL;
+	nodep->deleteTree(); VL_DANGLING(nodep);
    }

    void replaceSelReplicate(AstSel* nodep) {
@@ -1382,7 +1379,7 @@ private:
 				  new AstConst(lsbp->fileline(), lsbp->toUInt() % fromp->width()),
 				  widthp);
 	newp->dtypeFrom(nodep);
-	nodep->replaceWith(newp); nodep->deleteTree(); nodep=NULL;
+	nodep->replaceWith(newp); nodep->deleteTree(); VL_DANGLING(nodep);
    }

    void replaceSelIntoBiop(AstSel* nodep) {
@@ -1400,7 +1397,7 @@ private:
 	fromp->rhsp(new AstSel(nodep->fileline(),
 			       birhsp, lsbp, widthp));
 	fromp->dtypeFrom(nodep);
-	nodep->replaceWith(fromp); nodep->deleteTree(); nodep=NULL;
+	nodep->replaceWith(fromp); nodep->deleteTree(); VL_DANGLING(nodep);
    }
    void replaceSelIntoUniop(AstSel* nodep) {
 	// SEL(NOT(a),1,bit) => NOT(SEL(a,bit))
@@ -1414,17 +1411,17 @@ private:
 	fromp->lhsp(new AstSel(nodep->fileline(),
 			       bilhsp, lsbp, widthp));
 	fromp->dtypeFrom(nodep);
-	nodep->replaceWith(fromp); nodep->deleteTree(); nodep=NULL;
+	nodep->replaceWith(fromp); nodep->deleteTree(); VL_DANGLING(nodep);
    }

-    virtual void visit(AstAttrOf* nodep, AstNUser*) {
+    virtual void visit(AstAttrOf* nodep) {
 	AstAttrOf* oldAttr = m_attrp;
 	m_attrp = nodep;
 	nodep->iterateChildren(*this);
 	m_attrp = oldAttr;
    }

-    virtual void visit(AstArraySel* nodep, AstNUser*) {
+    virtual void visit(AstArraySel* nodep) {
 	nodep->bitp()->iterateAndNext(*this);
 	if (nodep->bitp()->castConst()
 	    && nodep->fromp()->castVarRef()
@@ -1438,12 +1435,17 @@ private:
 	    if (!m_selp) {
 		nodep->v3error("Illegal assignment of constant to unpacked array");
 	    } else {
-		nodep->replaceWith(nodep->fromp()->unlinkFrBack());
+		AstNode* fromp = nodep->fromp()->unlinkFrBack();
+		nodep->replaceWith(fromp);
+		if (fromp->dtypep()->skipRefp()->castNodeArrayDType()) {
+		    // Strip off array to find what array references
+		    fromp->dtypeFrom(fromp->dtypep()->skipRefp()->castNodeArrayDType()->subDTypep());
+		}
 	    }
 	}
 	m_selp = NULL;
    }
-    virtual void visit(AstVarRef* nodep, AstNUser*) {
+    virtual void visit(AstNodeVarRef* nodep) {
 	nodep->iterateChildren(*this);
 	if (!nodep->varp()) nodep->v3fatalSrc("Not linked");
 	bool did=false;
@@ -1463,17 +1465,29 @@ private:
 		if (operandConst(valuep)) {
 		    const V3Number& num = valuep->castConst()->num();
 		    //UINFO(2,"constVisit "<<(void*)valuep<<" "<<num<<endl);
-		    replaceNum(nodep, num); nodep=NULL;
+		    replaceNum(nodep, num); VL_DANGLING(nodep);
 		    did=true;
 		}
 		else if (m_selp && valuep->castInitArray()) {
-		    int bit = m_selp->bitConst();
-		    AstNode* itemp = valuep->castInitArray()->initsp();
-		    for (int n=0; n<bit && itemp; ++n, itemp=itemp->nextp()) {}
+		    AstInitArray* initarp = valuep->castInitArray();
+		    uint32_t bit = m_selp->bitConst();
+		    int pos = 0;
+		    AstNode* itemp = initarp->initsp();
+		    for (; itemp; ++pos, itemp=itemp->nextp()) {
+			uint32_t index = initarp->posIndex(pos);
+			if (index == bit) break;
+			if (index > bit) {
+			    if (initarp->defaultp()) {
+				itemp = initarp->defaultp();
+			    } else {
+				initarp->v3fatalSrc("Not enough values in array initalizement");
+			    }
+			}
+		    }
 		    if (itemp->castConst()) {
 			const V3Number& num = itemp->castConst()->num();
 			//UINFO(2,"constVisit "<<(void*)valuep<<" "<<num<<endl);
-			replaceNum(nodep, num); nodep=NULL;
+			replaceNum(nodep, num); VL_DANGLING(nodep);
 			did=true;
 		    }
 		}
@@ -1483,7 +1497,7 @@ private:
 	    nodep->v3error("Expecting expression to be constant, but variable isn't const: "<<nodep->varp()->prettyName());
 	}
    }
-    virtual void visit(AstEnumItemRef* nodep, AstNUser*) {
+    virtual void visit(AstEnumItemRef* nodep) {
 	nodep->iterateChildren(*this);
 	if (!nodep->itemp()) nodep->v3fatalSrc("Not linked");
 	bool did=false;
@@ -1492,7 +1506,7 @@ private:
 	    nodep->itemp()->valuep()->iterateAndNext(*this);
 	    if (AstConst* valuep = nodep->itemp()->valuep()->castConst()) {
 		const V3Number& num = valuep->num();
-		replaceNum(nodep, num); nodep=NULL;
+		replaceNum(nodep, num); VL_DANGLING(nodep);
 		did=true;
 	    }
 	}
@@ -1501,7 +1515,7 @@ private:
 	}
    }

-    // virtual void visit(AstCvtPackString* nodep, AstNUser*) {
+    // virtual void visit(AstCvtPackString* nodep) {
    // Not constant propagated (for today) because AstMath::isOpaque is set
    // Someday if lower is constant, convert to quoted "string".

@@ -1509,7 +1523,7 @@ private:
 	// Only one if it's not in a list
 	return (!nodep->nextp() && nodep->backp()->nextp() != nodep);
    }
-    virtual void visit(AstSenItem* nodep, AstNUser*) {
+    virtual void visit(AstSenItem* nodep) {
 	nodep->iterateChildren(*this);
 	if (m_doNConst
 	    && (nodep->sensp()->castConst()
@@ -1519,13 +1533,13 @@ private:
 	    if (nodep->isClocked()) {  // A constant can never get a pos/negexge
 		if (onlySenItemInSenTree(nodep)) {
 		    nodep->replaceWith(new AstSenItem(nodep->fileline(), AstSenItem::Never()));
-		    nodep->deleteTree(); nodep=NULL;
+		    nodep->deleteTree(); VL_DANGLING(nodep);
 		} else {
-		    nodep->unlinkFrBack()->deleteTree(); nodep=NULL;
+		    nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
 		}
 	    } else {  // Otherwise it may compute a result that needs to settle out
 		nodep->replaceWith(new AstSenItem(nodep->fileline(), AstSenItem::Combo()));
-		nodep->deleteTree(); nodep=NULL;
+		nodep->deleteTree(); VL_DANGLING(nodep);
 	    }
 	} else if (m_doNConst && nodep->sensp()->castNot()) {
 	    // V3Gate may propagate NOTs into clocks... Just deal with it
@@ -1541,30 +1555,31 @@ private:
 	    AstNodeVarRef* senvarp = lastSensp->unlinkFrBack()->castNodeVarRef();
 	    if (!senvarp) sensp->v3fatalSrc("Non-varref sensitivity variable");
 	    sensp->replaceWith(senvarp);
-	    sensp->deleteTree(); sensp=NULL;
+	    sensp->deleteTree(); VL_DANGLING(sensp);
 	} else if (!m_doNConst  // Deal with later when doNConst missing
 		   && (nodep->sensp()->castEnumItemRef()
 		       || nodep->sensp()->castConst())) {
+	} else if (nodep->isIllegal()) {  // Deal with later
 	} else {
 	    if (nodep->hasVar() && !nodep->varrefp()) nodep->v3fatalSrc("Null sensitivity variable");
 	}
    }
-    virtual void visit(AstSenGate* nodep, AstNUser*) {
+    virtual void visit(AstSenGate* nodep) {
 	nodep->iterateChildren(*this);
 	if (AstConst* constp = nodep->rhsp()->castConst()) {
 	    if (constp->isZero()) {
 		UINFO(4,"SENGATE(...,0)->NEVER"<<endl);
 		if (onlySenItemInSenTree(nodep)) {
 		    nodep->replaceWith(new AstSenItem(nodep->fileline(), AstSenItem::Never()));
-		    nodep->deleteTree(); nodep=NULL;
+		    nodep->deleteTree(); VL_DANGLING(nodep);
 		} else {
-		    nodep->unlinkFrBack()->deleteTree(); nodep=NULL;
+		    nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
 		}
 	    } else {
 		UINFO(4,"SENGATE(SENITEM,0)->ALWAYS SENITEM"<<endl);
 		AstNode* senitemp = nodep->sensesp()->unlinkFrBack();
 		nodep->replaceWith(senitemp);
-		nodep->deleteTree(); nodep=NULL;
+		nodep->deleteTree(); VL_DANGLING(nodep);
 	    }
 	}
    }
@@ -1595,7 +1610,7 @@ private:
 	}
    };

-    virtual void visit(AstSenTree* nodep, AstNUser*) {
+    virtual void visit(AstSenTree* nodep) {
 	nodep->iterateChildren(*this);
 	if (m_doExpensive) {
 	    //cout<<endl; nodep->dumpTree(cout,"ssin: ");
@@ -1630,7 +1645,7 @@ private:
 				    // Found, push this item up to the top
 				    itemp->unlinkFrBack();
 				    nodep->addSensesp(itemp);
-				    gatep->unlinkFrBack()->deleteTree(); gatep=NULL; senp=NULL;
+				    gatep->unlinkFrBack()->deleteTree(); VL_DANGLING(gatep); VL_DANGLING(senp);
 				}
 			    }
 			}
@@ -1686,7 +1701,7 @@ private:
 				&& ritemp->edgeType()==AstEdgeType::ET_NEGEDGE)
 				litemp->edgeType(AstEdgeType::ET_BOTHEDGE);
 			    // Remove redundant node
-			    ritemp->unlinkFrBack()->deleteTree(); ritemp=NULL; cmpp=NULL;
+			    ritemp->unlinkFrBack()->deleteTree(); VL_DANGLING(ritemp); VL_DANGLING(cmpp);
 			    // Try to collapse again
 			    nextp=litemp;
 			}
@@ -1699,17 +1714,17 @@ private:

    //-----
    // Zero elimination
-    virtual void visit(AstNodeAssign* nodep, AstNUser*) {
+    virtual void visit(AstNodeAssign* nodep) {
 	nodep->iterateChildren(*this);
 	if (m_doNConst && replaceNodeAssign(nodep)) return;
    }
-    virtual void visit(AstAssignAlias* nodep, AstNUser*) {
+    virtual void visit(AstAssignAlias* nodep) {
 	// Don't perform any optimizations, keep the alias around
    }
-    virtual void visit(AstAssignVarScope* nodep, AstNUser*) {
+    virtual void visit(AstAssignVarScope* nodep) {
 	// Don't perform any optimizations, the node won't be linked yet
    }
-    virtual void visit(AstAssignW* nodep, AstNUser*) {
+    virtual void visit(AstAssignW* nodep) {
 	nodep->iterateChildren(*this);
 	if (m_doNConst && replaceNodeAssign(nodep)) return;
 	AstNodeVarRef* varrefp = nodep->lhsp()->castVarRef();  // Not VarXRef, as different refs may set different values to each hierarchy
@@ -1729,14 +1744,14 @@ private:
 				 new AstAssign(nodep->fileline(),
 					       varrefp, exprp));
 	    m_modp->addStmtp(newinitp);
-	    nodep->unlinkFrBack()->deleteTree();  nodep=NULL;
+	    nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
 	    // Set the initial value right in the variable so we can constant propagate
 	    AstNode* initvaluep = exprp->cloneTree(false);
 	    varrefp->varp()->valuep(initvaluep);
 	}
    }

-    virtual void visit(AstNodeIf* nodep, AstNUser*) {
+    virtual void visit(AstNodeIf* nodep) {
 	nodep->iterateChildren(*this);
 	if (m_doNConst) {
 	    if (AstConst* constp = nodep->condp()->castConst()) {
@@ -1754,12 +1769,12 @@ private:
 		} else {
 		    nodep->unlinkFrBack();
 		}
-		nodep->deleteTree(); nodep=NULL;
+		nodep->deleteTree(); VL_DANGLING(nodep);
 	    }
 	    else if (!afterComment(nodep->ifsp()) && !afterComment(nodep->elsesp())) {
 		// Empty block, remove it
 		// Note if we support more C++ then there might be side effects in the condition itself
-		nodep->unlinkFrBack()->deleteTree(); nodep=NULL;
+		nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
 	    }
 	    else if (!afterComment(nodep->ifsp())) {
 		UINFO(4,"IF({x}) NULL {...} => IF(NOT{x}}: "<<nodep<<endl);
@@ -1781,7 +1796,7 @@ private:
 		AstIf* ifp = new AstIf(nodep->fileline(), condp, elsesp, ifsp);
 		ifp->branchPred(nodep->branchPred().invert());
 		nodep->replaceWith(ifp);
-		nodep->deleteTree(); nodep=NULL;
+		nodep->deleteTree(); VL_DANGLING(nodep);
 	    }
 	    else if (ifSameAssign(nodep)) {
 		UINFO(4,"IF({a}) ASSIGN({b},{c}) else ASSIGN({b},{d}) => ASSIGN({b}, {a}?{c}:{d})"<<endl);
@@ -1794,7 +1809,7 @@ private:
 		ifp->rhsp(new AstCond(truep->fileline(),
 				      condp, truep, falsep));
 		nodep->replaceWith(ifp);
-		nodep->deleteTree(); nodep=NULL;
+		nodep->deleteTree(); VL_DANGLING(nodep);
 	    }
 	    else if (0	// Disabled, as vpm assertions are faster without due to short-circuiting
 		     && operandIfIf(nodep)) {
@@ -1806,7 +1821,7 @@ private:
 		nodep->condp(new AstLogAnd(lowerIfp->fileline(),
 					   condp, lowerCondp));
 		lowerIfp->replaceWith(lowerIfsp);
-		lowerIfp->deleteTree(); lowerIfp=NULL;
+		lowerIfp->deleteTree(); VL_DANGLING(lowerIfp);
 	    }
 	    else if (operandBoolShift(nodep->condp())) {
 		replaceBoolShift(nodep->condp());
@@ -1814,7 +1829,7 @@ private:
 	}
    }

-    virtual void visit(AstSFormatF* nodep, AstNUser*) {
+    virtual void visit(AstSFormatF* nodep) {
 	// Substitute constants into displays.  The main point of this is to
 	// simplify assertion methodologies which call functions with display's.
 	// This eliminates a pile of wide temps, and makes the C a whole lot more readable.
@@ -1825,7 +1840,7 @@ private:
 	}
 	if (m_doNConst && anyconst) {
 	    //UINFO(9,"  Display in  "<<nodep->text()<<endl);
-	    string dispout = "";
+	    string newFormat = "";
 	    string fmt = "";
 	    bool inPct = false;
 	    AstNode* argp = nodep->exprsp();
@@ -1843,84 +1858,82 @@ private:
 		    switch (tolower(ch)) {
 		    case '%': break;  // %% - just output a %
 		    case 'm': break;  // %m - auto insert "name"
+		    case 'l': break;  // %l - auto insert "library"
 		    default:  // Most operators, just move to next argument
 			if (argp) {
 			    AstNode* nextp=argp->nextp();
 			    if (argp && argp->castConst()) { // Convert it
-				string out = argp->castConst()->num().displayed(fmt);
+				string out = argp->castConst()->num().displayed(nodep->fileline(), fmt);
 				UINFO(9,"     DispConst: "<<fmt<<" -> "<<out<<"  for "<<argp<<endl);
-				{   // fmt = out w/ replace % with %% as it must be literal.
-				    fmt = "";
-				    for (string::iterator pos = out.begin(); pos != out.end(); ++pos) {
-					if (*pos == '%') fmt += '%';
-					fmt += *pos;
-				    }
-				}
+				// fmt = out w/ replace % with %% as it must be literal.
+				fmt = VString::quotePercent(out);
 				argp->unlinkFrBack()->deleteTree();
 			    }
 			    argp=nextp;
 			}
 			break;
 		    } // switch
-		    dispout += fmt;
+		    newFormat += fmt;
 		} else {
-		    dispout += ch;
+		    newFormat += ch;
 		}
 	    }
-	    nodep->text(dispout);
-	    //UINFO(9,"  Display out "<<nodep->text()<<endl);
+	    if (newFormat != nodep->text()) {
+		nodep->text(newFormat);
+		UINFO(9,"  Display out "<<nodep<<endl);
+	    }
 	}
 	if (!nodep->exprsp()
 	    && nodep->name().find("%") == string::npos
 	    && !nodep->hidden()) {
 	    // Just a simple constant string - the formatting is pointless
-	    replaceConstString(nodep, nodep->name()); nodep=NULL;
+	    replaceConstString(nodep, nodep->name()); VL_DANGLING(nodep);
 	}
    }

-    virtual void visit(AstFuncRef* nodep, AstNUser*) {
+    virtual void visit(AstFuncRef* nodep) {
 	nodep->iterateChildren(*this);
 	if (m_params) {  // Only parameters force us to do constant function call propagation
 	    replaceWithSimulation(nodep);
 	}
    }
-    virtual void visit(AstArg* nodep, AstNUser*) {
+    virtual void visit(AstArg* nodep) {
 	// replaceWithSimulation on the Arg's parent FuncRef replaces these
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstWhile* nodep, AstNUser*) {
+    virtual void visit(AstWhile* nodep) {
 	nodep->iterateChildren(*this);
 	if (m_doNConst) {
 	    if (nodep->condp()->isZero()) {
 		UINFO(4,"WHILE(0) => nop "<<nodep<<endl);
 		if (nodep->precondsp()) nodep->replaceWith(nodep->precondsp());
 		else nodep->unlinkFrBack();
-		nodep->deleteTree(); nodep=NULL;
+		nodep->deleteTree(); VL_DANGLING(nodep);
 	    }
 	    else if (operandBoolShift(nodep->condp())) {
 		replaceBoolShift(nodep->condp());
 	    }
 	}
    }
-    virtual void visit(AstInitArray* nodep, AstNUser*) {
+    virtual void visit(AstInitArray* nodep) {
 	// Constant if all children are constant
 	nodep->iterateChildren(*this);
    }

    // These are converted by V3Param.  Don't constify as we don't want the from() VARREF to disappear, if any
    // If output of a presel didn't get consted, chances are V3Param didn't visit properly
-    virtual void visit(AstNodePreSel* nodep, AstNUser*) {}
+    virtual void visit(AstNodePreSel* nodep) {}

    // Ignored, can eliminate early
-    virtual void visit(AstSysIgnore* nodep, AstNUser*) {
+    virtual void visit(AstSysIgnore* nodep) {
 	nodep->iterateChildren(*this);
 	if (m_doNConst) {
-	    nodep->unlinkFrBack()->deleteTree(); nodep=NULL;
+	    nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
 	}
    }

    // Simplify
-    virtual void visit(AstBasicDType* nodep, AstNUser*) {
+    virtual void visit(AstBasicDType* nodep) {
 	nodep->iterateChildren(*this);
 	nodep->cvtRangeConst();
    }
@@ -1928,12 +1941,12 @@ private:
    //-----
    // Jump elimination

-    virtual void visit(AstJumpGo* nodep, AstNUser*) {
+    virtual void visit(AstJumpGo* nodep) {
 	nodep->iterateChildren(*this);
 	if (m_doExpensive) { nodep->labelp()->user4(true); }
    }

-    virtual void visit(AstJumpLabel* nodep, AstNUser*) {
+    virtual void visit(AstJumpLabel* nodep) {
 	// Because JumpLabels disable many optimizations,
 	// remove JumpLabels that are not pointed to by any AstJumpGos
 	// Note this assumes all AstJumpGos are underneath the given label; V3Broken asserts this
@@ -1945,7 +1958,7 @@ private:
 	    if (nodep->stmtsp()) underp = nodep->stmtsp()->unlinkFrBackWithNext();
 	    if (underp) nodep->replaceWith(underp);
 	    else nodep->unlinkFrBack();
-	    nodep->deleteTree(); nodep=NULL;
+	    nodep->deleteTree(); VL_DANGLING(nodep);
 	}
    }

@@ -2262,11 +2275,15 @@ private:
    // Note we can't convert EqCase/NeqCase to Eq/Neq here because that would break 3'b1x1==3'b101

    //-----
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	// Default: Just iterate
 	if (m_required) {
-	    nodep->v3error("Expecting expression to be constant, but can't convert a "
-			   <<nodep->prettyTypeName()<<" to constant.");
+	    if (nodep->castNodeDType() || nodep->castRange()) {
+		// Ignore dtypes for parameter type pins
+	    } else {
+		nodep->v3error("Expecting expression to be constant, but can't convert a "
+			       <<nodep->prettyTypeName()<<" to constant.");
+	    }
 	} else {
 	    // Calculate the width of this operation
 	    if (m_params && !nodep->width()) {
@@ -2289,7 +2306,7 @@ public:
    };

    // CONSTUCTORS
-    ConstVisitor(ProcMode pmode) {
+    explicit ConstVisitor(ProcMode pmode) {
 	m_params = false;
 	m_required = false;
 	m_doExpensive = false;
@@ -2318,7 +2335,7 @@ public:
    virtual ~ConstVisitor() {}
    AstNode* mainAcceptEdit(AstNode* nodep) {
 	// Operate starting at a random place
-	return nodep->acceptSubtreeReturnEdits(*this);
+	return nodep->iterateSubtreeReturnEdits(*this);
    }
 };

@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -83,11 +83,11 @@ private:
    const char* varIgnoreToggle(AstVar* nodep) {
 	// Return true if this shouldn't be traced
 	// See also similar rule in V3TraceDecl::varIgnoreTrace
-	string prettyName = nodep->prettyName();
 	if (!nodep->isToggleCoverable())
 	    return "Not relevant signal type";
 	if (!v3Global.opt.coverageUnderscore()) {
-	    if (prettyName.c_str()[0] == '_')
+	    string prettyName = nodep->prettyName();
+	    if (prettyName[0] == '_')
 	        return "Leading underscore";
 	    if (prettyName.find("._") != string::npos)
 	        return "Inlined leading underscore";
@@ -128,7 +128,7 @@ private:
    }

    // VISITORS - BOTH
-    virtual void visit(AstNodeModule* nodep, AstNUser*) {
+    virtual void visit(AstNodeModule* nodep) {
 	m_modp = nodep;
 	m_inModOff = nodep->isTop();   // Ignore coverage on top module; it's a shell we created
 	m_fileps.clear();
@@ -138,7 +138,7 @@ private:
    }

    // VISITORS - TOGGLE COVERAGE
-    virtual void visit(AstNodeFTask* nodep, AstNUser*) {
+    virtual void visit(AstNodeFTask* nodep) {
 	bool oldtog = m_inToggleOff;
 	{
 	    m_inToggleOff = true;
@@ -146,7 +146,7 @@ private:
 	}
 	m_inToggleOff = oldtog;
    }
-    virtual void visit(AstVar* nodep, AstNUser*) {
+    virtual void visit(AstVar* nodep) {
 	nodep->iterateChildren(*this);
 	if (m_modp && !m_inModOff && !m_inToggleOff
 	    && nodep->fileline()->coverageOn() && v3Global.opt.coverageToggle()) {
@@ -279,7 +279,7 @@ private:
    }

    // VISITORS - LINE COVERAGE
-    virtual void visit(AstIf* nodep, AstNUser*) { // Note not AstNodeIf; other types don't get covered
+    virtual void visit(AstIf* nodep) { // Note not AstNodeIf; other types don't get covered
 	UINFO(4," IF: "<<nodep<<endl);
 	if (m_checkBlock) {
 	    // An else-if.  When we iterate the if, use "elsif" marking
@@ -312,7 +312,7 @@ private:
 	    m_checkBlock = true;  // Reset as a child may have cleared it
 	}
    }
-    virtual void visit(AstCaseItem* nodep, AstNUser*) {
+    virtual void visit(AstCaseItem* nodep) {
 	UINFO(4," CASEI: "<<nodep<<endl);
 	if (m_checkBlock && !m_inModOff
 	    && nodep->fileline()->coverageOn() && v3Global.opt.coverageLine()) {
@@ -324,7 +324,7 @@ private:
 	    m_checkBlock = true;  // Reset as a child may have cleared it
 	}
    }
-    virtual void visit(AstPslCover* nodep, AstNUser*) {
+    virtual void visit(AstPslCover* nodep) {
 	UINFO(4," PSLCOVER: "<<nodep<<endl);
 	m_checkBlock = true;  // Always do cover blocks, even if there's a $stop
 	nodep->iterateChildren(*this);
@@ -334,21 +334,21 @@ private:
 	}
 	m_checkBlock = true;  // Reset as a child may have cleared it
    }
-    virtual void visit(AstStop* nodep, AstNUser*) {
+    virtual void visit(AstStop* nodep) {
 	UINFO(4,"  STOP: "<<nodep<<endl);
 	m_checkBlock = false;
    }
-    virtual void visit(AstPragma* nodep, AstNUser*) {
+    virtual void visit(AstPragma* nodep) {
 	if (nodep->pragType() == AstPragmaType::COVERAGE_BLOCK_OFF) {
 	    // Skip all NEXT nodes under this block, and skip this if/case branch
 	    UINFO(4,"  OFF: "<<nodep<<endl);
 	    m_checkBlock = false;
-	    nodep->unlinkFrBack()->deleteTree(); nodep=NULL;
+	    nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
 	} else {
 	    if (m_checkBlock) nodep->iterateChildren(*this);
 	}
    }
-    virtual void visit(AstBegin* nodep, AstNUser*) {
+    virtual void visit(AstBegin* nodep) {
 	// Record the hierarchy of any named begins, so we can apply to user
 	// coverage points.  This is because there may be cov points inside
 	// generate blocks; each point should get separate consideration.
@@ -368,7 +368,7 @@ private:
    }

    // VISITORS - BOTH
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	// Default: Just iterate
 	if (m_checkBlock) {
 	    nodep->iterateChildren(*this);
@@ -378,7 +378,7 @@ private:

 public:
    // CONSTUCTORS
-    CoverageVisitor(AstNetlist* rootp) {
+    explicit CoverageVisitor(AstNetlist* rootp) {
 	// Operate on all modules
 	m_checkBlock = true;
 	m_beginHier = "";
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -93,7 +93,7 @@ private:
 		    UINFO(8,"   new "<<removep->incp()->declp()<<endl);
 		    // Mark the found node as a duplicate of the first node
 		    // (Not vice-versa as we have the iterator for the found node)
-		    removep->unlinkFrBack();  pushDeletep(removep); removep=NULL;
+		    removep->unlinkFrBack();  pushDeletep(removep); VL_DANGLING(removep);
 		    // Remove node from comparison so don't hit it again
 		    hashed.erase(dupit);
 		    ++m_statToggleJoins;
@@ -103,25 +103,25 @@ private:
    }

    // VISITORS
-    virtual void visit(AstNetlist* nodep, AstNUser*) {
+    virtual void visit(AstNetlist* nodep) {
 	// Find all Coverage's
 	nodep->iterateChildren(*this);
 	// Simplify
 	detectDuplicates();
    }
-    virtual void visit(AstCoverToggle* nodep, AstNUser*) {
+    virtual void visit(AstCoverToggle* nodep) {
 	m_toggleps.push_back(nodep);
 	nodep->iterateChildren(*this);
    }
    //--------------------
-    virtual void visit(AstNodeMath* nodep, AstNUser*) {}  // Accelerate
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNodeMath* nodep) {}  // Accelerate
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }

 public:
    // CONSTUCTORS
-    CoverageJoinVisitor(AstNetlist* nodep) {
+    explicit CoverageJoinVisitor(AstNetlist* nodep) {
 	nodep->accept(*this);
    }
    virtual ~CoverageJoinVisitor() {
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -25,7 +25,18 @@
 // dependencies easier to resolve.
 // NOTE: If redo this, consider using maybePointedTo()/broken() ish scheme
 // instead of needing as many visitors.
-//*************************************************************************
+//
+// The following nodes have package pointers and are cleaned up here:
+// AstRefDType, AstEnumItemRef, AstNodeVarRef, AstNodeFTask
+// These have packagep but will not exist at this stage
+// AstPackageImport, AstDot, AstPackageRef
+//
+// Note on packagep: After the V3Scope/V3LinkDotScoped stage, package links
+// are no longer used, but their presence prevents us from removing empty
+// packages. As the links as no longer used after V3Scope, we remove them
+// here after scoping to allow more dead node
+// removal.
+// *************************************************************************

 #include "config_build.h"
 #include "verilatedos.h"
@@ -47,18 +58,18 @@ private:
    // NODE STATE
    // ** Shared with DeadVisitor **
    // VISITORS
-    virtual void visit(AstCell* nodep, AstNUser*) {
+    virtual void visit(AstCell* nodep) {
 	nodep->iterateChildren(*this);
-	nodep->modp()->user1(nodep->modp()->user1() - 1);
+	nodep->modp()->user1Inc(-1);
    }
    //-----
-    virtual void visit(AstNodeMath* nodep, AstNUser*) {}  // Accelerate
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNodeMath* nodep) {}  // Accelerate
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }
 public:
    // CONSTRUCTORS
-    DeadModVisitor(AstNodeModule* nodep) {
+    explicit DeadModVisitor(AstNodeModule* nodep) {
 	nodep->accept(*this);
    }
    virtual ~DeadModVisitor() {}
@@ -71,10 +82,10 @@ class DeadVisitor : public AstNVisitor {
 private:
    // NODE STATE
    // Entire Netlist:
-    //  AstNodeModule::user1()	-> int. Count of number of cells referencing this module.
-    //  AstVar::user1()		-> int. Count of number of references
-    //  AstVarScope::user1()	-> int. Count of number of references
-    //  AstNodeDType::user1()	-> int. Count of number of references
+    //	AstNodeModule::user1()	-> int. Count of number of cells referencing this module.
+    //	AstVar::user1()		-> int. Count of number of references
+    //	AstVarScope::user1()	-> int. Count of number of references
+    //	AstNodeDType::user1()	-> int. Count of number of references
    AstUser1InUse	m_inuser1;

    // TYPES
@@ -82,11 +93,16 @@ private:

    // STATE
    AstNodeModule*		m_modp;		// Current module
-    vector<AstNode*>		m_varEtcsp;	// List of all encountered to avoid another loop through tree
+    vector<AstVar*>		m_varsp;	// List of all encountered to avoid another loop through tree
+    vector<AstNode*>		m_dtypesp;	// List of all encountered to avoid another loop through tree
    vector<AstVarScope*>	m_vscsp;	// List of all encountered to avoid another loop through tree
+    vector<AstScope*>		m_scopesp;	// List of all encountered to avoid another loop through tree
+    vector<AstCell*>		m_cellsp;	// List of all encountered to avoid another loop through tree
    AssignMap			m_assignMap;	// List of all simple assignments for each variable
    bool			m_elimUserVars;	// Allow removal of user's vars
    bool			m_elimDTypes;	// Allow removal of DTypes
+    bool			m_elimScopes;	// Allow removal of Scopes
+    bool			m_elimCells;	// Allow removal of Cells
    bool			m_sideEffect;	// Side effects discovered in assign RHS

    // METHODS
@@ -97,34 +113,56 @@ private:
    }

    void checkAll(AstNode* nodep) {
-	if (nodep != nodep->dtypep()) {  // NodeDTypes reference themselves
-	    if (AstNode* subnodep = nodep->dtypep()) subnodep->user1Inc();
+	if (nodep != nodep->dtypep()) {	 // NodeDTypes reference themselves
+	    if (AstNode* subnodep = nodep->dtypep()) {
+		subnodep->user1Inc();
+	    }
+	}
+	if (AstNode* subnodep = nodep->getChildDTypep()) {
+	    subnodep->user1Inc();
 	}
-	if (AstNode* subnodep = nodep->getChildDTypep()) subnodep->user1Inc();
    }
    void checkDType(AstNodeDType* nodep) {
 	if (!nodep->generic()  // Don't remove generic types
 	    && m_elimDTypes  // dtypes stick around until post-widthing
 	    && !nodep->castMemberDType() // Keep member names iff upper type exists
 	    ) {
-	    m_varEtcsp.push_back(nodep);
+	    m_dtypesp.push_back(nodep);
+	}
+	if (AstNode* subnodep = nodep->virtRefDTypep()) {
+	    subnodep->user1Inc();
 	}
-	if (AstNode* subnodep = nodep->virtRefDTypep()) subnodep->user1Inc();
    }

    // VISITORS
-    virtual void visit(AstNodeModule* nodep, AstNUser*) {
+    virtual void visit(AstNodeModule* nodep) {
 	m_modp = nodep;
 	nodep->iterateChildren(*this);
 	checkAll(nodep);
 	m_modp = NULL;
    }
-    virtual void visit(AstCell* nodep, AstNUser*) {
+    virtual void visit(AstCFunc* nodep) {
 	nodep->iterateChildren(*this);
 	checkAll(nodep);
+	if (nodep->scopep()) nodep->scopep()->user1Inc();
+    }
+    virtual void visit(AstScope* nodep) {
+	nodep->iterateChildren(*this);
+	checkAll(nodep);
+	if (nodep->aboveScopep()) nodep->aboveScopep()->user1Inc();
+
+	if (!nodep->isTop() && !nodep->varsp() && !nodep->blocksp() && !nodep->finalClksp()) {
+	    m_scopesp.push_back(nodep);
+	}
+    }
+    virtual void visit(AstCell* nodep) {
+	nodep->iterateChildren(*this);
+	checkAll(nodep);
+	m_cellsp.push_back(nodep);
 	nodep->modp()->user1Inc();
    }
-    virtual void visit(AstNodeVarRef* nodep, AstNUser*) {
+
+    virtual void visit(AstNodeVarRef* nodep) {
 	nodep->iterateChildren(*this);
 	checkAll(nodep);
 	if (nodep->varScopep()) {
@@ -135,60 +173,79 @@ private:
 	    nodep->varp()->user1Inc();
 	}
 	if (nodep->packagep()) {
-	    nodep->packagep()->user1Inc();
+	    if (m_elimCells) nodep->packagep(NULL);
+	    else nodep->packagep()->user1Inc();
 	}
    }
-    virtual void visit(AstNodeFTaskRef* nodep, AstNUser*) {
+    virtual void visit(AstNodeFTaskRef* nodep) {
 	nodep->iterateChildren(*this);
 	checkAll(nodep);
 	if (nodep->packagep()) {
-	    nodep->packagep()->user1Inc();
+	    if (m_elimCells) nodep->packagep(NULL);
+	    else nodep->packagep()->user1Inc();
 	}
    }
-    virtual void visit(AstRefDType* nodep, AstNUser*) {
+    virtual void visit(AstRefDType* nodep) {
 	nodep->iterateChildren(*this);
 	checkDType(nodep);
 	checkAll(nodep);
 	if (nodep->packagep()) {
-	    nodep->packagep()->user1Inc();
+	    if (m_elimCells) nodep->packagep(NULL);
+	    else nodep->packagep()->user1Inc();
 	}
    }
-    virtual void visit(AstNodeDType* nodep, AstNUser*) {
+    virtual void visit(AstNodeDType* nodep) {
 	nodep->iterateChildren(*this);
 	checkDType(nodep);
 	checkAll(nodep);
    }
-    virtual void visit(AstEnumItemRef* nodep, AstNUser*) {
+    virtual void visit(AstEnumItemRef* nodep) {
 	nodep->iterateChildren(*this);
 	checkAll(nodep);
 	if (nodep->packagep()) {
-	    nodep->packagep()->user1Inc();
+	    if (m_elimCells) nodep->packagep(NULL);
+	    else nodep->packagep()->user1Inc();
 	}
+	checkAll(nodep);
    }
-    virtual void visit(AstTypedef* nodep, AstNUser*) {
+    virtual void visit(AstModport* nodep) {
 	nodep->iterateChildren(*this);
+	if (m_elimCells) {
+	    if (!nodep->varsp()) {
+		pushDeletep(nodep->unlinkFrBack()); VL_DANGLING(nodep);
+		return;
+	    }
+	}
+	checkAll(nodep);
+    }
+    virtual void visit(AstTypedef* nodep) {
+	nodep->iterateChildren(*this);
+	if (m_elimCells && !nodep->attrPublic()) {
+	    pushDeletep(nodep->unlinkFrBack()); VL_DANGLING(nodep);
+	    return;
+	}
 	checkAll(nodep);
 	// Don't let packages with only public variables disappear
 	// Normal modules may disappear, e.g. if they are parameterized then removed
 	if (nodep->attrPublic() && m_modp && m_modp->castPackage()) m_modp->user1Inc();
    }
-    virtual void visit(AstVarScope* nodep, AstNUser*) {
+    virtual void visit(AstVarScope* nodep) {
 	nodep->iterateChildren(*this);
 	checkAll(nodep);
-	if (mightElim(nodep->varp())) {
+	if (nodep->scopep()) nodep->scopep()->user1Inc();
+	if (mightElimVar(nodep->varp())) {
 	    m_vscsp.push_back(nodep);
 	}
    }
-    virtual void visit(AstVar* nodep, AstNUser*) {
+    virtual void visit(AstVar* nodep) {
 	nodep->iterateChildren(*this);
 	checkAll(nodep);
 	if (nodep->isSigPublic() && m_modp && m_modp->castPackage()) m_modp->user1Inc();
-	if (mightElim(nodep)) {
-	    m_varEtcsp.push_back(nodep);
+	if (mightElimVar(nodep)) {
+	    m_varsp.push_back(nodep);
 	}
    }
-
-    virtual void visit(AstNodeAssign* nodep, AstNUser*) {
+    virtual void visit(AstNodeAssign* nodep) {
 	// See if simple assignments to variables may be eliminated because that variable is never used.
 	// Similar code in V3Life
 	m_sideEffect = false;
@@ -199,7 +256,7 @@ private:
 	if (varrefp && !m_sideEffect
 	    && varrefp->varScopep()) {	// For simplicity, we only remove post-scoping
 	    m_assignMap.insert(make_pair(varrefp->varScopep(), nodep));
-	    checkAll(varrefp);  // Must track reference to dtype()
+	    checkAll(varrefp);	// Must track reference to dtype()
 	} else {  // Track like any other statement
 	    nodep->lhsp()->iterateAndNext(*this);
 	}
@@ -207,7 +264,7 @@ private:
    }

    //-----
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	if (nodep->isOutputter()) m_sideEffect=true;
 	nodep->iterateChildren(*this);
 	checkAll(nodep);
@@ -229,19 +286,51 @@ private:
 		    // And its children may now be killable too; correct counts
 		    // Recurse, as cells may not be directly under the module but in a generate
 		    DeadModVisitor visitor(modp);
-		    modp->unlinkFrBack()->deleteTree(); modp=NULL;
+		    modp->unlinkFrBack()->deleteTree(); VL_DANGLING(modp);
 		    retry = true;
 		}
 	    }
 	}
    }
-    bool mightElim(AstVar* nodep) {
+    bool mightElimVar(AstVar* nodep) {
 	return (!nodep->isSigPublic()	// Can't elim publics!
 		&& !nodep->isIO()
 		&& (nodep->isTemp()
 		    || (nodep->isParam() && !nodep->isTrace())
 		    || m_elimUserVars));  // Post-Trace can kill most anything
    }
+
+    void deadCheckScope() {
+	for (bool retry=true; retry; ) {
+	    retry = false;
+	    for (vector<AstScope*>::iterator it = m_scopesp.begin(); it != m_scopesp.end();++it) {
+		AstScope* scp = *it;
+		if (!scp)
+		    continue;
+		if (scp->user1() == 0) {
+		    UINFO(4, "	Dead AstScope " << scp << endl);
+		    scp->aboveScopep()->user1Inc(-1);
+		    if (scp->dtypep()) {
+			scp->dtypep()->user1Inc(-1);
+		    }
+		    scp->unlinkFrBack()->deleteTree(); VL_DANGLING(scp);
+		    *it = NULL;
+		    retry = true;
+		}
+	    }
+	}
+    }
+
+    void deadCheckCells() {
+	for (vector<AstCell*>::iterator it = m_cellsp.begin(); it!=m_cellsp.end(); ++it) {
+	    AstCell* cellp = *it;
+	    if (cellp->user1() == 0 && !cellp->modp()->stmtsp()) {
+		cellp->modp()->user1Inc(-1);
+		cellp->unlinkFrBack()->deleteTree(); VL_DANGLING(cellp);
+	    }
+	}
+    }
+
    void deadCheckVar() {
 	// Delete any unused varscopes
 	for (vector<AstVarScope*>::iterator it = m_vscsp.begin(); it!=m_vscsp.end(); ++it) {
@@ -251,34 +340,76 @@ private:
 		pair <AssignMap::iterator,AssignMap::iterator> eqrange = m_assignMap.equal_range(vscp);
 		for (AssignMap::iterator it = eqrange.first; it != eqrange.second; ++it) {
 		    AstNodeAssign* assp = it->second;
-		    UINFO(4,"    Dead assign "<<assp<<endl);
-		    assp->unlinkFrBack()->deleteTree(); assp=NULL;
+		    UINFO(4,"	 Dead assign "<<assp<<endl);
+		    assp->dtypep()->user1Inc(-1);
+		    assp->unlinkFrBack()->deleteTree(); VL_DANGLING(assp);
 		}
-		vscp->unlinkFrBack()->deleteTree(); vscp=NULL;
+		if (vscp->scopep()) vscp->scopep()->user1Inc(-1);
+		vscp->dtypep()->user1Inc(-1);
+		vscp->unlinkFrBack()->deleteTree(); VL_DANGLING(vscp);
 	    }
 	}
-	for (vector<AstNode*>::iterator it = m_varEtcsp.begin(); it!=m_varEtcsp.end(); ++it) {
+	for (bool retry=true; retry; ) {
+	    retry = false;
+	    for (vector<AstVar *>::iterator it = m_varsp.begin(); it != m_varsp.end();++it) {
+		AstVar* varp = *it;
+		if (!varp)
+		    continue;
+		if (varp->user1() == 0) {
+		    UINFO(4, "	Dead " << varp << endl);
+		    if (varp->dtypep()) {
+			varp->dtypep()->user1Inc(-1);
+		    }
+		    varp->unlinkFrBack()->deleteTree(); VL_DANGLING(varp);
+		    *it = NULL;
+		    retry = true;
+		}
+	    }
+	}
+	for (vector<AstNode*>::iterator it = m_dtypesp.begin(); it != m_dtypesp.end();++it) {
 	    if ((*it)->user1() == 0) {
-		UINFO(4,"  Dead "<<(*it)<<endl);
-		(*it)->unlinkFrBack()->deleteTree(); (*it)=NULL;
+		AstNodeClassDType *classp;
+		// It's possible that there if a reference to each individual member, but
+		// not to the dtype itself.  Check and don't remove the parent dtype if
+		// members are still alive.
+		if ((classp = (*it)->castNodeClassDType())) {
+		    bool cont = true;
+		    for (AstMemberDType *memberp = classp->membersp(); memberp; memberp = memberp->nextp()->castMemberDType()) {
+			if (memberp->user1() != 0) {
+			    cont = false;
+			    break;
+			}
+		    }
+		    if (!cont)
+			continue;
+		}
+		(*it)->unlinkFrBack()->deleteTree(); VL_DANGLING(*it);
 	    }
 	}
    }

 public:
    // CONSTRUCTORS
-    DeadVisitor(AstNetlist* nodep, bool elimUserVars, bool elimDTypes) {
+    DeadVisitor(AstNetlist* nodep, bool elimUserVars, bool elimDTypes, bool elimScopes, bool elimCells) {
 	m_modp = NULL;
+	m_elimCells = elimCells;
 	m_elimUserVars = elimUserVars;
 	m_elimDTypes = elimDTypes;
+	m_elimScopes = elimScopes;
 	m_sideEffect = false;
 	// Prepare to remove some datatypes
 	nodep->typeTablep()->clearCache();
 	// Operate on whole netlist
 	nodep->accept(*this);
+
 	deadCheckVar();
+	// We only elimate scopes when in a flattened structure
+	// Otherwise we have no easy way to know if a scope is used
+	if (elimScopes) deadCheckScope();
+	if (elimCells) deadCheckCells();
 	// Modules after vars, because might be vars we delete inside a mod we delete
 	deadCheckMod();
+
 	// We may have removed some datatypes, cleanup
 	nodep->typeTablep()->repairCache();
    }
@@ -290,16 +421,30 @@ public:

 void V3Dead::deadifyModules(AstNetlist* nodep) {
    UINFO(2,__FUNCTION__<<": "<<endl);
-    DeadVisitor visitor (nodep, false, false);
+    DeadVisitor visitor (nodep, false, false, false, false);
    V3Global::dumpCheckGlobalTree("deadModules.tree", 0, v3Global.opt.dumpTreeLevel(__FILE__) >= 6);
 }
+
 void V3Dead::deadifyDTypes(AstNetlist* nodep) {
    UINFO(2,__FUNCTION__<<": "<<endl);
-    DeadVisitor visitor (nodep, false, true);
-    V3Global::dumpCheckGlobalTree("deadDType.tree", 0, v3Global.opt.dumpTreeLevel(__FILE__) >= 3);
+    DeadVisitor visitor (nodep, false, true, false, false);
+    V3Global::dumpCheckGlobalTree("deadDtypes.tree", 0, v3Global.opt.dumpTreeLevel(__FILE__) >= 3);
 }
+
+void V3Dead::deadifyDTypesScoped(AstNetlist* nodep) {
+    UINFO(2,__FUNCTION__<<": "<<endl);
+    DeadVisitor visitor (nodep, false, true, true, false);
+    V3Global::dumpCheckGlobalTree("deadDtypesScoped.tree", 0, v3Global.opt.dumpTreeLevel(__FILE__) >= 3);
+}
+
 void V3Dead::deadifyAll(AstNetlist* nodep) {
    UINFO(2,__FUNCTION__<<": "<<endl);
-    DeadVisitor visitor (nodep, true, true);
+    DeadVisitor visitor (nodep, true, true, false, true);
    V3Global::dumpCheckGlobalTree("deadAll.tree", 0, v3Global.opt.dumpTreeLevel(__FILE__) >= 3);
 }
+
+void V3Dead::deadifyAllScoped(AstNetlist* nodep) {
+    UINFO(2,__FUNCTION__<<": "<<endl);
+    DeadVisitor visitor (nodep, true, true, true, true);
+    V3Global::dumpCheckGlobalTree("deadAllScoped.tree", 0, v3Global.opt.dumpTreeLevel(__FILE__) >= 3);
+}
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -33,8 +33,10 @@ public:
    static void deadifyModules(AstNetlist* nodep);
    // Modules, Data types
    static void deadifyDTypes(AstNetlist* nodep);
+    static void deadifyDTypesScoped(AstNetlist* nodep);
    // Everything that's possible
    static void deadifyAll(AstNetlist* nodep);
+    static void deadifyAllScoped(AstNetlist* nodep);
 };

 #endif // Guard
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -268,7 +268,7 @@ private:
 	    // then we told this nodep->user3 we can use its Vdlyvset rather than making a new one.
 	    // This is good for code like:
 	    //    for (i=0; i<5; i++)  vector[i] <= something;
-	    setvscp = nodep->user3p()->castNode()->castVarScope();
+	    setvscp = nodep->user3p()->castVarScope();
 	    ++m_statSharedSet;
 	} else {  // Create new one
 	    string setvarname = (string("__Vdlyvset__")+oldvarp->shortName()+"__v"+cvtToStr(modVecNum));
@@ -303,9 +303,9 @@ private:
 	// Build "IF (changeit) ...
 	UINFO(9,"   For "<<setvscp<<endl);
 	UINFO(9,"     & "<<varrefp<<endl);
-	AstAlwaysPost* finalp = varrefp->varScopep()->user4p()->castNode()->castAlwaysPost();
+	AstAlwaysPost* finalp = varrefp->varScopep()->user4p()->castAlwaysPost();
 	if (finalp) {
-	    AstActive* oldactivep = finalp->user2p()->castNode()->castActive();
+	    AstActive* oldactivep = finalp->user2p()->castActive();
 	    checkActivePost(varrefp, oldactivep);
 	    if (setinitp) oldactivep->addStmtsp(setinitp);
 	} else { // first time we've dealt with this memory
@@ -318,10 +318,10 @@ private:
 	    if (setinitp) newactp->addStmtsp(setinitp);
 	}
 	AstIf* postLogicp;
-	if (finalp->user3p()->castNode() == setvscp) {
+	if (finalp->user3p() == setvscp) {
 	    // Optimize as above; if sharing Vdlyvset *ON SAME VARIABLE*,
 	    // we can share the IF statement too
-	    postLogicp = finalp->user4p()->castNode()->castIf();
+	    postLogicp = finalp->user4p()->castIf();
 	    if (!postLogicp) nodep->v3fatalSrc("Delayed assignment misoptimized; prev var found w/o associated IF");
 	} else {
 	    postLogicp = new AstIf (nodep->fileline(),
@@ -338,22 +338,22 @@ private:
    }

    // VISITORS
-    virtual void visit(AstNetlist* nodep, AstNUser*) {
+    virtual void visit(AstNetlist* nodep) {
 	//VV*****  We reset all userp() on the netlist
 	m_modVarMap.clear();
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstScope* nodep, AstNUser*) {
+    virtual void visit(AstScope* nodep) {
 	UINFO(4," MOD   "<<nodep<<endl);
 	AstNode::user3ClearTree();
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstCFunc* nodep, AstNUser*) {
+    virtual void visit(AstCFunc* nodep) {
 	m_cfuncp = nodep;
 	nodep->iterateChildren(*this);
 	m_cfuncp = NULL;
    }
-    virtual void visit(AstActive* nodep, AstNUser*) {
+    virtual void visit(AstActive* nodep) {
 	m_activep = nodep;
 	bool oldinit = m_inInitial;
 	m_inInitial = nodep->hasInitial();
@@ -361,7 +361,7 @@ private:
 	nodep->iterateChildren(*this);
 	m_inInitial = oldinit;
    }
-    virtual void visit(AstAssignDly* nodep, AstNUser*) {
+    virtual void visit(AstAssignDly* nodep) {
 	m_inDly = true;
 	m_nextDlyp = nodep->nextp()->castAssignDly();  // Next assignment in same block, maybe NULL.
 	if (m_cfuncp) nodep->v3error("Unsupported: Delayed assignment inside public function/task");
@@ -374,9 +374,9 @@ private:
 	    if (newlhsp) {
 		nodep->lhsp(newlhsp);
 	    } else {
-		nodep->unlinkFrBack()->deleteTree(); nodep=NULL;
+		nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
 	    }
-	    lhsp->deleteTree(); lhsp=NULL;
+	    lhsp->deleteTree(); VL_DANGLING(lhsp);
 	}
 	else {
 	    nodep->iterateChildren(*this);
@@ -385,7 +385,7 @@ private:
 	m_nextDlyp = NULL;
    }

-    virtual void visit(AstVarRef* nodep, AstNUser*) {
+    virtual void visit(AstVarRef* nodep) {
 	if (!nodep->user2Inc()) {  // Not done yet
 	    if (m_inDly && nodep->lvalue()) {
 		UINFO(4,"AssignDlyVar: "<<nodep<<endl);
@@ -394,9 +394,9 @@ private:
 		if (!m_activep->hasClocked()) nodep->v3error("Internal: Blocking <= assignment in non-clocked block, should have converted in V3Active");
 		AstVarScope* oldvscp = nodep->varScopep();
 		if (!oldvscp) nodep->v3fatalSrc("Var didn't get varscoped in V3Scope.cpp\n");
-		AstVarScope* dlyvscp = oldvscp->user1p()->castNode()->castVarScope();
+		AstVarScope* dlyvscp = oldvscp->user1p()->castVarScope();
 		if (dlyvscp) {  // Multiple use of delayed variable
-		    AstActive* oldactivep = dlyvscp->user2p()->castNode()->castActive();
+		    AstActive* oldactivep = dlyvscp->user2p()->castActive();
 		    checkActivePost(nodep, oldactivep);
 		}
 		if (!dlyvscp) {  // First use of this delayed variable
@@ -420,7 +420,7 @@ private:
 		}
 		AstVarRef* newrefp = new AstVarRef(nodep->fileline(), dlyvscp, true);
 		newrefp->user2(true);  // No reason to do it again
-		nodep->replaceWith(newrefp); nodep->deleteTree(); nodep=NULL;
+		nodep->replaceWith(newrefp); nodep->deleteTree(); VL_DANGLING(nodep);
 	    }
 	    else if (!m_inDly && nodep->lvalue()) {
 		//UINFO(9,"NBA "<<nodep<<endl);
@@ -432,10 +432,10 @@ private:
 	}
    }

-    virtual void visit(AstNodeFor* nodep, AstNUser*) {
+    virtual void visit(AstNodeFor* nodep) {
 	nodep->v3fatalSrc("For statements should have been converted to while statements in V3Begin\n");
    }
-    virtual void visit(AstWhile* nodep, AstNUser*) {
+    virtual void visit(AstWhile* nodep) {
 	bool oldloop = m_inLoop;
 	m_inLoop = true;
 	nodep->iterateChildren(*this);
@@ -444,13 +444,13 @@ private:

    //--------------------
    // Default: Just iterate
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }

 public:
    // CONSTUCTORS
-    DelayedVisitor(AstNetlist* nodep) {
+    explicit DelayedVisitor(AstNetlist* nodep) {
 	m_inDly = false;
 	m_activep=NULL;
 	m_cfuncp=NULL;
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -85,14 +85,14 @@ private:
    }

    // VISITORS
-    virtual void visit(AstNodeModule* nodep, AstNUser*) {
+    virtual void visit(AstNodeModule* nodep) {
 	UINFO(4," MOD   "<<nodep<<endl);
 	m_modp = nodep;
 	m_funcp = NULL;
 	nodep->iterateChildren(*this);
 	m_modp = NULL;
    }
-    virtual void visit(AstCFunc* nodep, AstNUser*) {
+    virtual void visit(AstCFunc* nodep) {
 	m_funcp = nodep;
 	m_depth = 0;
 	m_maxdepth = 0;
@@ -106,13 +106,13 @@ private:
 	nodep->iterateChildren(*this);
 	m_stmtp = NULL;
    }
-    virtual void visit(AstNodeStmt* nodep, AstNUser*) {
+    virtual void visit(AstNodeStmt* nodep) {
 	visitStmt(nodep);
    }
    // Operators
-    virtual void visit(AstNodeTermop* nodep, AstNUser*) {
+    virtual void visit(AstNodeTermop* nodep) {
    }
-    virtual void visit(AstNodeMath* nodep, AstNUser*) {
+    virtual void visit(AstNodeMath* nodep) {
 	// We have some operator defines that use 2 parens, so += 2.
 	m_depth += 2;
 	if (m_depth>m_maxdepth) m_maxdepth=m_depth;
@@ -139,25 +139,25 @@ private:
 	    m_funcp->isStatic(false);
 	}
    }
-    virtual void visit(AstUCFunc* nodep, AstNUser*) {
+    virtual void visit(AstUCFunc* nodep) {
 	needNonStaticFunc(nodep);
 	nodep->iterateChildren(*this);
    }
-    virtual void visit(AstUCStmt* nodep, AstNUser*) {
+    virtual void visit(AstUCStmt* nodep) {
 	needNonStaticFunc(nodep);
 	visitStmt(nodep);
    }

    //--------------------
    // Default: Just iterate
-    virtual void visit(AstVar* nodep, AstNUser*) {}	// Don't hit varrefs under vars
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstVar* nodep) {}	// Don't hit varrefs under vars
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }

 public:
    // CONSTUCTORS
-    DepthVisitor(AstNetlist* nodep) {
+    explicit DepthVisitor(AstNetlist* nodep) {
 	m_modp=NULL;
 	m_funcp=NULL;
 	m_stmtp=NULL;
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -6,7 +6,7 @@
 //
 //*************************************************************************
 //
-// Copyright 2003-2015 by Wilson Snyder.  This program is free software; you can
+// Copyright 2003-2017 by Wilson Snyder.  This program is free software; you can
 // redistribute it and/or modify it under the terms of either the GNU
 // Lesser General Public License Version 3 or the Perl Artistic License
 // Version 2.0.
@@ -76,14 +76,14 @@ private:
    }

    // VISITORS
-    virtual void visit(AstNodeModule* nodep, AstNUser*) {
+    virtual void visit(AstNodeModule* nodep) {
 	UINFO(4," MOD   "<<nodep<<endl);
 	m_modp = nodep;
 	m_deepNum = 0;
 	nodep->iterateChildren(*this);
 	m_modp = NULL;
    }
-    virtual void visit(AstCFunc* nodep, AstNUser*) {
+    virtual void visit(AstCFunc* nodep) {
 	// We recurse into this.
 	int lastDepth = m_depth;
 	AstCFunc* lastFuncp = m_funcp;
@@ -111,21 +111,21 @@ private:
 	}
 	m_depth--;
    }
-    virtual void visit(AstNodeStmt* nodep, AstNUser*) {
+    virtual void visit(AstNodeStmt* nodep) {
 	visitStmt(nodep);
    }

-    virtual void visit(AstNodeMath* nodep, AstNUser*) {}  // Accelerate
+    virtual void visit(AstNodeMath* nodep) {}  // Accelerate
    //--------------------
    // Default: Just iterate
-    virtual void visit(AstVar* nodep, AstNUser*) {}	// Don't hit varrefs under vars
-    virtual void visit(AstNode* nodep, AstNUser*) {
+    virtual void visit(AstVar* nodep) {}	// Don't hit varrefs under vars
+    virtual void visit(AstNode* nodep) {
 	nodep->iterateChildren(*this);
    }

 public:
    // CONSTUCTORS
-    DepthBlockVisitor(AstNetlist* nodep) {
+    explicit DepthBlockVisitor(AstNetlist* nodep) {
 	m_modp=NULL;
 	m_depth=0;
 	//
--- a/Show More
+++ b/Show More