Fix hang on recursive substitution `defines, bug443.

Changes

@@ -18,6 +18,9 @@ indicates the contributor was also the author of the fix; Thanks!
 
 ****  Fix hang when functions inside begin block. [David Welch]
 
+****  Fix hang on recursive substitution `defines, bug443. [Alex Solomatnikov]
+
+
 * Verilator 3.831 2012/01/20
 
 **    Support SystemC 2.3.0 prerelease.  This requires setting the new

src/V3PreLex.h

@@ -34,6 +34,7 @@
 
 //======================================================================
 
+class V3PreLex;
 class V3PreProcImp;
 
 // Token codes
@@ -126,16 +127,23 @@ void yy_delete_buffer( YY_BUFFER_STATE b );
 class VPreStream {
 public:
     FileLine*		m_curFilelinep;	// Current processing point (see also m_tokFilelinep)
+    V3PreLex*		m_lexp;		// Lexer, for resource tracking
     deque<string>	m_buffers;	// Buffer of characters to process
     int			m_ignNewlines;	// Ignore multiline newlines
     bool		m_eof;		// "EOF" buffer
     bool		m_file;		// Buffer is start of new file
     int			m_termState;	// Termination fsm
-    VPreStream(FileLine* fl)
-	: m_curFilelinep(fl), m_ignNewlines(0),
+    VPreStream(FileLine* fl, V3PreLex* lexp)
+	: m_curFilelinep(fl), m_lexp(lexp),
+	  m_ignNewlines(0),
 	  m_eof(false), m_file(false), m_termState(0) {
+	lexStreamDepthAdd(1);
     }
-    ~VPreStream() {}
+    ~VPreStream() {
+	lexStreamDepthAdd(-1);
+    }
+private:
+    void lexStreamDepthAdd(int delta);
 };
 
 //======================================================================
@@ -145,6 +153,7 @@ class V3PreLex {
   public:	// Used only by V3PreLex.cpp and V3PreProc.cpp
     V3PreProcImp*	m_preimpp;	// Preprocessor lexor belongs to
     stack<VPreStream*>	m_streampStack;	// Stack of processing files
+    int			m_streamDepth;	// Depth of stream processing
     YY_BUFFER_STATE	m_bufferState;	// Flex state
     FileLine*		m_tokFilelinep;	// Starting position of current token
 
@@ -166,6 +175,7 @@ class V3PreLex {
     // CONSTRUCTORS
     V3PreLex(V3PreProcImp* preimpp, FileLine* filelinep) {
 	m_preimpp = preimpp;
+	m_streamDepth = 0;
 	m_keepComments = 0;
 	m_keepWhitespace = 1;
 	m_pedantic = false;
@@ -207,6 +217,9 @@ class V3PreLex {
     void dumpSummary();
     void dumpStack();
     void unused();
+    // Called by VPreStream
+    void streamDepthAdd(int delta) { m_streamDepth += delta; }
+    int streamDepth() const { return m_streamDepth; }
     /// Utility
     static int debug();
     static void debug(int level);
@@ -219,4 +232,6 @@ private:
     void scanSwitchStream(VPreStream* streamp);
 };
 
+inline void VPreStream::lexStreamDepthAdd(int delta) { m_lexp->streamDepthAdd(delta); }
+
 #endif // Guard

src/V3PreLex.l

@@ -432,7 +432,7 @@ string V3PreLex::endOfStream(bool& againr) {
 void V3PreLex::initFirstBuffer(FileLine* filelinep) {
     // Called from constructor to make first buffer
     // yy_create_buffer also sets yy_fill_buffer=1 so reads from YY_INPUT
-    VPreStream* streamp = new VPreStream(filelinep);
+    VPreStream* streamp = new VPreStream(filelinep, this);
     streamp->m_eof = true;
     m_streampStack.push(streamp);
     //
@@ -443,10 +443,16 @@ void V3PreLex::initFirstBuffer(FileLine* filelinep) {
 
 void V3PreLex::scanNewFile(FileLine* filelinep) {
     // Called on new open file.  scanBytesBack will be called next.
-    VPreStream* streamp = new VPreStream(filelinep);
-    m_tokFilelinep = curFilelinep();
-    streamp->m_file = true;
-    scanSwitchStream(streamp);
+    if (streamDepth() > V3PreProc::DEFINE_RECURSION_LEVEL_MAX) {
+	// The recursive `include in VPreProcImp should trigger first
+	yyerrorf("Recursive `define or other nested inclusion");
+	curStreamp()->m_eof = true;  // Fake it to stop recursion
+    } else {
+	VPreStream* streamp = new VPreStream(filelinep, this);
+	m_tokFilelinep = curFilelinep();
+	streamp->m_file = true;
+	scanSwitchStream(streamp);
+    }
 }
 
 void V3PreLex::scanBytes(const string& str) {
@@ -455,9 +461,16 @@ void V3PreLex::scanBytes(const string& str) {
     // to take effect immediately, in the middle of the current buffer
     // Also we don't use scan_bytes that would set yy_fill_buffer
     // which would force Flex to bypass our YY_INPUT routine.
-    VPreStream* streamp = new VPreStream(curFilelinep());
-    streamp->m_buffers.push_front(str);
-    scanSwitchStream(streamp);
+    if (streamDepth() > V3PreProc::DEFINE_RECURSION_LEVEL_MAX) {
+	// More streams if recursive `define with complex insertion
+	// More buffers mostly if something internal goes funky
+	yyerrorf("Recursive `define or other nested inclusion");
+	curStreamp()->m_eof = true;  // Fake it to stop recursion
+    } else {
+	VPreStream* streamp = new VPreStream(curFilelinep(), this);
+	streamp->m_buffers.push_front(str);
+	scanSwitchStream(streamp);
+    }
 }
 
 void V3PreLex::scanSwitchStream(VPreStream* streamp) {

src/V3PreProc.cpp

@@ -112,7 +112,7 @@ struct V3PreProcImp : public V3PreProc {
     typedef std::map<string,V3Define> DefinesMap;
     typedef V3InFilter::StrList StrList;
 
-    // debug() -> see V3PreShellImp::debug
+    // debug() -> see V3PreShellImp::debug; use --debugi-V3PreShell
 
     // Defines list
     DefinesMap	m_defines;	///< Map of defines

src/V3PreProc.h

@@ -50,6 +50,8 @@ public:
     enum MiscConsts {
 	DEFINE_RECURSION_LEVEL_MAX = 1000,	// How many `def substitutions before an error
 	INCLUDE_DEPTH_MAX = 500,		// How many `includes deep before an error
+	STREAM_DEPTH_LEVEL_MAX = 2000,		// How many streams deep (sometimes `def deep) before an error
+	//					// Set more than DEFINE_RECURSION_LEVEL_MAX or INCLUDE_DEPTH_MAX
 	NEWLINES_VS_TICKLINE = 20		// Use `line in place of this many newlines
     };
 

test_regress/t/t_pp_circdef_bad.pl

@@ -0,0 +1,23 @@
+#!/usr/bin/perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2003 by Wilson Snyder. This program is free software; you can
+# redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+
+$Self->{vlt} or $Self->skip("Verilator only test");
+
+compile (
+	 v_flags2 => ["--lint-only"],
+	 fails=>1,
+	 expect=>
+'%Error: t/t_pp_circdef_bad.v:\d+: Recursive `define or other nested inclusion
+.*
+%Error: Exiting due to.*',
+    );
+
+ok(1);
+1;
+

test_regress/t/t_pp_circdef_bad.v

@@ -0,0 +1,13 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed into the Public Domain, for any use,
+// without warranty, 2011 by Wilson Snyder.
+//
+// bug445
+
+`define WIDTH  12
+`define SEL_NUM_BITS `WIDTH-`SEL_NUM_BITS +: `SEL_NUM_BITS
+`define SEL_BITS     `WIDTH-`SEL_NUM_BITS +: `SEL_NUM_BITS
+`define ADDR_BITS    0 +: `WIDTH-`SEL_NUM_BITS
+
+typedef logic [`SEL_NUM_BITS-1:0]  d_t;