Merge branch 'package-imports-rework'

Makefile.in

@@ -118,9 +118,9 @@ O = main.o async.o design_dump.o discipline.o dup_expr.o elaborate.o \
     pform_disciplines.o pform_dump.o pform_package.o pform_pclass.o \
     pform_class_type.o pform_string_type.o pform_struct_type.o pform_types.o \
     symbol_search.o sync.o sys_funcs.o verinum.o verireal.o target.o \
-    Attrib.o HName.o Module.o PClass.o PDelays.o PEvent.o PExpr.o PGate.o \
+    Attrib.o HName.o Module.o PClass.o PDelays.o PEvent.o PExpr.o PFunction.o \
-    PGenerate.o PModport.o PPackage.o PScope.o PSpec.o PTask.o PUdp.o \
+    PGate.o PGenerate.o PModport.o PNamedItem.o PPackage.o PScope.o PSpec.o \
-    PFunction.o PWire.o Statement.o AStatement.o $M $(FF) $(TT)
+    PTask.o PUdp.o PWire.o Statement.o AStatement.o $M $(FF) $(TT)
 
 all: dep config.h _pli_types.h version_tag.h ivl@EXEEXT@ version.exe iverilog-vpi.man
 	$(foreach dir,$(SUBDIRS),$(MAKE) -C $(dir) $@ && ) true

Module.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998-2017 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 1998-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -122,3 +122,13 @@ const list<PGate*>& Module::get_gates() const
 {
       return gates_;
 }
+
+PNamedItem::SymbolType Module::symbol_type() const
+{
+      if (program_block)
+            return PROGRAM;
+      if (is_interface)
+            return INTERFACE;
+
+      return MODULE;
+}

Module.h

@@ -1,7 +1,7 @@
 #ifndef IVL_Module_H
 #define IVL_Module_H
 /*
- * Copyright (c) 1998-2017 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 1998-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -28,7 +28,7 @@
 # include  "HName.h"
 # include  "named.h"
 # include  "PScope.h"
-# include  "LineInfo.h"
+# include  "PNamedItem.h"
 # include  "netlist.h"
 # include  "pform_types.h"
 class PExpr;
@@ -54,7 +54,7 @@ class NetScope;
  * these containers as well.
  */
 
-class Module : public PScopeExtra, public LineInfo {
+class Module : public PScopeExtra, public PNamedItem {
 
 	/* The module ports are in general a vector of port_t
 	   objects. Each port has a name and an ordered list of
@@ -97,7 +97,7 @@ class Module : public PScopeExtra, public LineInfo {
 	/* specparams are simpler than other parameters, in that they
 	   can have a range, but not an explicit type. The restrictions
 	   are enforced by the parser. */
-      map<perm_string,param_expr_t>specparams;
+      map<perm_string,param_expr_t*>specparams;
 
 	/* The module also has defparam assignments which don't create
 	   new parameters within the module, but may be used to set
@@ -160,6 +160,8 @@ class Module : public PScopeExtra, public LineInfo {
 
       bool elaborate_sig(Design*, NetScope*scope) const;
 
+      SymbolType symbol_type() const;
+
     private:
       void dump_specparams_(ostream&out, unsigned indent) const;
       list<PGate*> gates_;

PClass.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2012-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -28,3 +28,8 @@ PClass::PClass(perm_string name, LexicalScope*parent)
 PClass::~PClass()
 {
 }
+
+PNamedItem::SymbolType PClass::symbol_type() const
+{
+      return CLASS;
+}

PClass.h

@@ -1,7 +1,7 @@
 #ifndef IVL_PClass_H
 #define IVL_PClass_H
 /*
- * Copyright (c) 2012-2014 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2012-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -20,7 +20,7 @@
  */
 
 # include  "PScope.h"
-# include  "LineInfo.h"
+# include  "PNamedItem.h"
 # include  "StringHeap.h"
 # include  <iostream>
 
@@ -32,7 +32,7 @@ class PChainConstructor;
  * collected.
  */
 
-class PClass : public PScopeExtra, public LineInfo {
+class PClass : public PScopeExtra, public PNamedItem {
 
     public:
       explicit PClass (perm_string name, LexicalScope*parent);
@@ -40,6 +40,8 @@ class PClass : public PScopeExtra, public LineInfo {
 
       void dump(std::ostream&out, unsigned indent) const;
 
+      SymbolType symbol_type() const;
+
     public:
       class_type_t*type;
 };

PEvent.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2004 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2004-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -35,3 +35,7 @@ perm_string  PEvent::name() const
       return name_;
 }
 
+PNamedItem::SymbolType PEvent::symbol_type() const
+{
+      return EVENT;
+}

PEvent.h

@@ -1,7 +1,7 @@
 #ifndef IVL_PEvent_H
 #define IVL_PEvent_H
 /*
- * Copyright (c) 2000-2014 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2000-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-# include  "LineInfo.h"
+# include  "PNamedItem.h"
 # include  "StringHeap.h"
 # include  <string>
 
@@ -31,7 +31,7 @@ class NetScope;
  * are declared in Verilog as ``event foo;'' The name passed to the
  * constructor is the "foo" part of the declaration.
  */
-class PEvent : public LineInfo {
+class PEvent : public PNamedItem {
 
     public:
 	// The name is a perm-allocated string. It is the simple name
@@ -43,6 +43,8 @@ class PEvent : public LineInfo {
 
       void elaborate_scope(Design*des, NetScope*scope) const;
 
+      SymbolType symbol_type() const;
+
     private:
       perm_string name_;
 

PExpr.h

@@ -1,7 +1,7 @@
 #ifndef IVL_PExpr_H
 #define IVL_PExpr_H
 /*
- * Copyright (c) 1998-2016 Stephen Williams <steve@icarus.com>
+ * Copyright (c) 1998-2019 Stephen Williams <steve@icarus.com>
  * Copyright CERN 2013 / Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
@@ -379,6 +379,8 @@ class PEIdent : public PExpr {
 
       virtual bool is_collapsible_net(Design*des, NetScope*scope) const;
 
+      const PPackage* package() const { return package_; }
+
       const pform_name_t& path() const { return path_; }
 
     private:

PFunction.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999-2013 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 1999-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -83,3 +83,8 @@ PChainConstructor* PFunction::extract_chain_constructor()
 
       return res;
 }
+
+PNamedItem::SymbolType PFunction::symbol_type() const
+{
+      return FUNCTION;
+}

PGate.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999-2013 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 1999-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -117,6 +117,11 @@ unsigned PGate::delay_count() const
       return delay_.delay_count();
 }
 
+PNamedItem::SymbolType PGate::symbol_type() const
+{
+      return INSTANCE;
+}
+
 PGAssign::PGAssign(list<PExpr*>*pins)
 : PGate(perm_string(), pins)
 {

PGate.h

@@ -1,7 +1,7 @@
 #ifndef IVL_PGate_H
 #define IVL_PGate_H
 /*
- * Copyright (c) 1998-2014 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 1998-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -22,7 +22,7 @@
 # include  "svector.h"
 # include  "StringHeap.h"
 # include  "named.h"
-# include  "LineInfo.h"
+# include  "PNamedItem.h"
 # include  "PDelays.h"
 # include  "netlist.h"
 # include  <map>
@@ -47,7 +47,7 @@ class Module;
  * single strength pair. There is a strength of the 0 drive, and a
  * strength of the 1 drive.
  */
-class PGate : public LineInfo {
+class PGate : public PNamedItem {
 
     public:
       explicit PGate(perm_string name, list<PExpr*>*pins,
@@ -88,6 +88,8 @@ class PGate : public LineInfo {
       virtual void elaborate_scope(Design*des, NetScope*sc) const;
       virtual bool elaborate_sig(Design*des, NetScope*scope) const;
 
+      SymbolType symbol_type() const;
+
     protected:
       const vector<PExpr*>& get_pins() const { return pins_; }
 

PGenerate.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2006-2011 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2006-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -112,3 +112,8 @@ ostream& operator << (ostream&out, PGenerate::scheme_t type)
       }
       return out;
 }
+
+PNamedItem::SymbolType PGenerate::symbol_type() const
+{
+      return GENBLOCK;
+}

PGenerate.h

@@ -1,7 +1,7 @@
 #ifndef IVL_PGenerate_H
 #define IVL_PGenerate_H
 /*
- * Copyright (c) 2006-2014 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2006-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-# include  "LineInfo.h"
+# include  "PNamedItem.h"
 # include  "StringHeap.h"
 # include  "HName.h"
 # include  "PScope.h"
@@ -50,7 +50,7 @@ class PWire;
  *    The parent points to the GS_CASE that contains this item.
  *    the loop_test is compared with the parent->loop_test expression.
  */
-class PGenerate : public LineInfo, public LexicalScope {
+class PGenerate : public PNamedItem, public LexicalScope {
 
     public:
       explicit PGenerate(LexicalScope*parent, unsigned id_number);
@@ -107,6 +107,8 @@ class PGenerate : public LineInfo, public LexicalScope {
 
       void dump(ostream&out, unsigned indent) const;
 
+      SymbolType symbol_type() const;
+
     private:
       bool generate_scope_loop_(Design*des, NetScope*container);
       bool generate_scope_condit_(Design*des, NetScope*container, bool else_flag);

PModport.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2015-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -29,3 +29,8 @@ PModport::PModport(perm_string n)
 PModport::~PModport()
 {
 }
+
+PNamedItem::SymbolType PModport::symbol_type() const
+{
+      return MODPORT;
+}

PModport.h

@@ -1,7 +1,7 @@
 #ifndef IVL_PModport_H
 #define IVL_PModport_H
 /*
- * Copyright (c) 2015 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2015-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-# include  "LineInfo.h"
+# include  "PNamedItem.h"
 # include  "PScope.h"
 # include  "StringHeap.h"
 # include  "netlist.h"
@@ -28,7 +28,7 @@
 /*
  * The PModport class represents a parsed SystemVerilog modport list.
  */
-class PModport : public LineInfo {
+class PModport : public PNamedItem {
 
     public:
 	// The name is a perm-allocated string. It is the simple name
@@ -41,6 +41,8 @@ class PModport : public LineInfo {
       typedef pair <NetNet::PortType,PExpr*> simple_port_t;
       map<perm_string,simple_port_t> simple_ports;
 
+      SymbolType symbol_type() const;
+
     private:
       perm_string name_;
 

PNamedItem.cc

@@ -0,0 +1,116 @@
+/*
+ * Copyright (c) 2019 Martin Whitaker (icarus@martin-whitaker.me.uk)
+ *
+ *    This source code is free software; you can redistribute it
+ *    and/or modify it in source code form under the terms of the GNU
+ *    General Public License as published by the Free Software
+ *    Foundation; either version 2 of the License, or (at your option)
+ *    any later version.
+ *
+ *    This program 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.
+ *
+ *    You should have received a copy of the GNU General Public License
+ *    along with this program; if not, write to the Free Software
+ *    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+# include  "PNamedItem.h"
+# include  <ostream>
+
+PNamedItem::PNamedItem()
+{
+}
+
+PNamedItem::~PNamedItem()
+{
+}
+
+PNamedItem::SymbolType PNamedItem::symbol_type() const
+{
+      return ANY;
+}
+
+std::ostream& operator << (std::ostream&o, PNamedItem::SymbolType st)
+{
+      switch (st) {
+          case PNamedItem::ANY:
+            o << "a symbol";
+            break;
+          case PNamedItem::PARAM:
+            o << "a parameter";
+            break;
+          case PNamedItem::NET:
+            o << "a net";
+            break;
+          case PNamedItem::VAR:
+            o << "a variable";
+            break;
+          case PNamedItem::GENVAR:
+            o << "a genvar";
+            break;
+          case PNamedItem::EVENT:
+            o << "an event";
+            break;
+          case PNamedItem::TYPE:
+            o << "a type";
+            break;
+          case PNamedItem::ENUM:
+            o << "an enum type or value";
+            break;
+          case PNamedItem::CLASS:
+            o << "a class";
+            break;
+          case PNamedItem::FUNCTION:
+            o << "a function";
+            break;
+          case PNamedItem::TASK:
+            o << "a task";
+            break;
+          case PNamedItem::BLOCK:
+            o << "a named block";
+            break;
+          case PNamedItem::GENBLOCK:
+            o << "a generate block";
+            break;
+          case PNamedItem::MODPORT:
+            o << "a modport";
+            break;
+          case PNamedItem::PACKAGE:
+            o << "a package";
+            break;
+          case PNamedItem::MODULE:
+            o << "a module";
+            break;
+          case PNamedItem::PROGRAM:
+            o << "a program";
+            break;
+          case PNamedItem::INTERFACE:
+            o << "an interface";
+            break;
+          case PNamedItem::PRIMITIVE:
+            o << "a primitive";
+            break;
+          case PNamedItem::INSTANCE:
+            o << "an instance name";
+            break;
+          default:
+            break;
+      }
+      return o;
+}
+
+PGenvar::PGenvar()
+{
+}
+
+PGenvar::~PGenvar()
+{
+}
+
+PNamedItem::SymbolType PGenvar::symbol_type() const
+{
+      return GENVAR;
+}

PNamedItem.h

@@ -0,0 +1,57 @@
+#ifndef IVL_PNamedItem_H
+#define IVL_PNamedItem_H
+/*
+ * Copyright (c) 2019 Martin Whitaker (icarus@martin-whitaker.me.uk)
+ *
+ *    This source code is free software; you can redistribute it
+ *    and/or modify it in source code form under the terms of the GNU
+ *    General Public License as published by the Free Software
+ *    Foundation; either version 2 of the License, or (at your option)
+ *    any later version.
+ *
+ *    This program 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.
+ *
+ *    You should have received a copy of the GNU General Public License
+ *    along with this program; if not, write to the Free Software
+ *    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+# include  "LineInfo.h"
+
+/*
+ * The PNamedItem class is the base class for all items that can be added
+ * to a scope's local symbol map.
+ */
+class PNamedItem : virtual public LineInfo {
+
+    public:
+      enum SymbolType { ANY, PARAM, NET, VAR, GENVAR, EVENT, TYPE, ENUM,
+                        CLASS, FUNCTION, TASK, BLOCK, GENBLOCK, MODPORT,
+                        PACKAGE, MODULE, PROGRAM, INTERFACE, PRIMITIVE,
+                        INSTANCE };
+
+      explicit PNamedItem();
+      virtual ~PNamedItem();
+
+      virtual SymbolType symbol_type() const;
+};
+
+extern std::ostream& operator << (std::ostream&, PNamedItem::SymbolType);
+
+/*
+ * The PGenvar class represents a genvar. This is only used to represent
+ * genvar in a scope's local symbol map.
+ */
+class PGenvar : public PNamedItem {
+
+    public:
+      explicit PGenvar();
+      virtual ~PGenvar();
+
+      SymbolType symbol_type() const;
+};
+
+#endif /* IVL_PNamedItem_H */

PScope.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008-2017 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2008-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -33,6 +33,11 @@ PWire* LexicalScope::wires_find(perm_string name)
 	    return (*cur).second;
 }
 
+PNamedItem::SymbolType LexicalScope::param_expr_t::symbol_type() const
+{
+      return PARAM;
+}
+
 PScope::PScope(perm_string n, LexicalScope*parent)
 : LexicalScope(parent), name_(n)
 {

PScope.h

@@ -1,7 +1,7 @@
 #ifndef IVL_PScope_H
 #define IVL_PScope_H
 /*
- * Copyright (c) 2008-2017 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2008-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-# include  "LineInfo.h"
+# include  "PNamedItem.h"
 # include  "StringHeap.h"
 # include  "pform_types.h"
 # include  "ivl_target.h"
@@ -61,6 +61,24 @@ class LexicalScope {
 
       lifetime_t default_lifetime;
 
+	// Symbols that are defined or declared in this scope.
+      std::map<perm_string,PNamedItem*>local_symbols;
+
+	// Symbols that are explicitly imported. Bind the imported name
+	// to the package from which the name is imported.
+      std::map<perm_string,PPackage*>explicit_imports;
+
+	// Packages that are wildcard imported. When identifiers from
+	// these packages are referenced, they will be added to the
+	// explicit imports (IEEE 1800-2012 26.3).
+      std::set<PPackage*>potential_imports;
+
+	// A task or function call may reference a task or function defined
+	// later in the scope. So here we stash the potential imports for
+	// task and function calls. They will be added to the explicit
+	// imports if we don't find a local definition.
+      std::map<perm_string,PPackage*>possible_imports;
+
       struct range_t {
 	      // True if this is an exclude
 	    bool exclude_flag;
@@ -79,7 +97,7 @@ class LexicalScope {
 	/* The scope has parameters that are evaluated when the scope
 	   is elaborated. During parsing, I put the parameters into
 	   this map. */
-      struct param_expr_t : public LineInfo {
+      struct param_expr_t : public PNamedItem {
 	    param_expr_t() : type(IVL_VT_NO_TYPE), msb(0), lsb(0), signed_flag(false), expr(0), range(0) { }
 	      // Type information
 	    ivl_variable_type_t type;
@@ -90,9 +108,11 @@ class LexicalScope {
 	    PExpr*expr;
 	      // If there are range constraints, list them here
 	    range_t*range;
+
+	    SymbolType symbol_type() const;
       };
-      map<perm_string,param_expr_t>parameters;
+      map<perm_string,param_expr_t*>parameters;
-      map<perm_string,param_expr_t>localparams;
+      map<perm_string,param_expr_t*>localparams;
 
 	// Defined types in the scope.
       map<perm_string,data_type_t*>typedefs;
@@ -100,10 +120,6 @@ class LexicalScope {
 	// Named events in the scope.
       map<perm_string,PEvent*>events;
 
-	// Symbols that are imported. Bind the imported name to the
-	// package from which the name is imported.
-      std::map<perm_string,PPackage*>imports;
-
 	// Nets and variables (wires) in the scope
       map<perm_string,PWire*>wires;
       PWire* wires_find(perm_string name);

PTask.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999-2008,2010 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 1999-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -73,3 +73,8 @@ void PTask::set_statement(Statement*s)
       assert(statement_ == 0);
       statement_ = s;
 }
+
+PNamedItem::SymbolType PTask::symbol_type() const
+{
+      return TASK;
+}

PTask.h

@@ -1,7 +1,7 @@
 #ifndef IVL_PTask_H
 #define IVL_PTask_H
 /*
- * Copyright (c) 1999-2014 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 1999-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -19,8 +19,8 @@
  *    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-# include  "LineInfo.h"
 # include  "PScope.h"
+# include  "PNamedItem.h"
 # include  "StringHeap.h"
 # include  <string>
 # include  <vector>
@@ -35,7 +35,7 @@ class Statement;
 class PExpr;
 
 
-class PTaskFunc : public PScope, public LineInfo {
+class PTaskFunc : public PScope, public PNamedItem {
 
     public:
       PTaskFunc(perm_string name, LexicalScope*parent);
@@ -99,6 +99,8 @@ class PTask  : public PTaskFunc {
 
       void dump(ostream&, unsigned) const;
 
+      SymbolType symbol_type() const;
+
     private:
       Statement*statement_;
       bool is_auto_;
@@ -148,6 +150,8 @@ class PFunction : public PTaskFunc {
 
       void dump(ostream&, unsigned) const;
 
+      SymbolType symbol_type() const;
+
     private:
       data_type_t* return_type_;
       Statement *statement_;

PWire.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999-2012 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 1999-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -283,3 +283,15 @@ ivl_discipline_t PWire::get_discipline(void) const
 {
       return discipline_;
 }
+
+PNamedItem::SymbolType PWire::symbol_type() const
+{
+      switch (type_) {
+          case NetNet::IMPLICIT_REG:
+          case NetNet::INTEGER:
+          case NetNet::REG:
+            return VAR;
+          default:
+            return NET;
+    }
+}

PWire.h

@@ -1,7 +1,7 @@
 #ifndef IVL_PWire_H
 #define IVL_PWire_H
 /*
- * Copyright (c) 1998-2014 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 1998-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -20,7 +20,7 @@
  */
 
 # include  "netlist.h"
-# include  "LineInfo.h"
+# include  "PNamedItem.h"
 # include  <list>
 # include  <map>
 # include  "StringHeap.h"
@@ -51,7 +51,7 @@ enum PWSRType {SR_PORT, SR_NET, SR_BOTH};
  * from that perspective, sub-scopes within the module are a part of
  * the wire name.
  */
-class PWire : public LineInfo {
+class PWire : public PNamedItem {
 
     public:
       PWire(perm_string name,
@@ -93,6 +93,8 @@ class PWire : public LineInfo {
 
       NetNet* elaborate_sig(Design*, NetScope*scope) const;
 
+      SymbolType symbol_type() const;
+
     private:
       perm_string name_;
       NetNet::Type type_;

Statement.cc

@@ -158,6 +158,11 @@ void PBlock::push_statement_front(Statement*that)
       list_[0] = that;
 }
 
+PNamedItem::SymbolType PBlock::symbol_type() const
+{
+      return BLOCK;
+}
+
 PCallTask::PCallTask(const pform_name_t&n, const list<PExpr*>&p)
 : package_(0), path_(n), parms_(p.size())
 {
@@ -411,8 +416,8 @@ PReturn::~PReturn()
       delete expr_;
 }
 
-PTrigger::PTrigger(const pform_name_t&e)
+PTrigger::PTrigger(PPackage*pkg, const pform_name_t&e)
-: event_(e)
+: package_(pkg), event_(e)
 {
 }
 

Statement.h

@@ -75,7 +75,7 @@ class PProcess : public LineInfo {
  * fact, the Statement class is abstract and represents all the
  * possible kinds of statements that exist in Verilog.
  */
-class Statement : public LineInfo {
+class Statement : virtual public LineInfo {
 
     public:
       Statement() { }
@@ -170,7 +170,7 @@ class PAssignNB  : public PAssign_ {
  * statements before constructing this object, so it knows a priori
  * what is contained.
  */
-class PBlock  : public PScope, public Statement {
+class PBlock  : public PScope, public Statement, public PNamedItem {
 
     public:
       enum BL_TYPE { BL_SEQ, BL_PAR, BL_JOIN_NONE, BL_JOIN_ANY };
@@ -205,6 +205,8 @@ class PBlock  : public PScope, public Statement {
       virtual void elaborate_scope(Design*des, NetScope*scope) const;
       virtual void elaborate_sig(Design*des, NetScope*scope) const;
 
+      SymbolType symbol_type() const;
+
     private:
       BL_TYPE bl_type_;
       std::vector<Statement*>list_;
@@ -561,13 +563,14 @@ class PReturn  : public Statement {
 class PTrigger  : public Statement {
 
     public:
-      explicit PTrigger(const pform_name_t&ev);
+      explicit PTrigger(PPackage*pkg, const pform_name_t&ev);
       ~PTrigger();
 
       virtual NetProc* elaborate(Design*des, NetScope*scope) const;
       virtual void dump(ostream&out, unsigned ind) const;
 
     private:
+      PPackage*package_;
       pform_name_t event_;
 };
 

elab_scope.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000-2017 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2000-2019 Stephen Williams (steve@icarus.com)
  * Copyright CERN 2013 / Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
@@ -63,7 +63,7 @@ void set_scope_timescale(Design*des, NetScope*scope, PScope*pscope)
       des->set_precision(pscope->time_precision);
 }
 
-typedef map<perm_string,LexicalScope::param_expr_t>::const_iterator mparm_it_t;
+typedef map<perm_string,LexicalScope::param_expr_t*>::const_iterator mparm_it_t;
 
 static void collect_parm_item_(Design*des, NetScope*scope, perm_string name,
 			       const LexicalScope::param_expr_t&cur,
@@ -110,59 +110,32 @@ static void collect_parm_item_(Design*des, NetScope*scope, perm_string name,
 }
 
 static void collect_scope_parameters_(Design*des, NetScope*scope,
-      const map<perm_string,LexicalScope::param_expr_t>&parameters)
+      const map<perm_string,LexicalScope::param_expr_t*>&parameters)
 {
       for (mparm_it_t cur = parameters.begin()
 		 ; cur != parameters.end() ;  ++ cur ) {
 
-	      // A parameter can not have the same name as a genvar.
+	    collect_parm_item_(des, scope, cur->first, *(cur->second), false, false);
-	    if (scope->find_genvar((*cur).first)) {
-		  cerr << cur->second.get_fileline()
-		       << ": error: parameter and genvar in '"
-		       << scope->fullname() << "' have the same name '"
-		       << (*cur).first << "'." << endl;
-		  des->errors += 1;
-	    }
-
-	    collect_parm_item_(des, scope, (*cur).first, (*cur).second, false, false);
       }
 }
 
 static void collect_scope_localparams_(Design*des, NetScope*scope,
-      const map<perm_string,LexicalScope::param_expr_t>&localparams)
+      const map<perm_string,LexicalScope::param_expr_t*>&localparams)
 {
       for (mparm_it_t cur = localparams.begin()
 		 ; cur != localparams.end() ;  ++ cur ) {
 
-	      // A localparam can not have the same name as a genvar.
+	    collect_parm_item_(des, scope, cur->first, *(cur->second), false, true);
-	    if (scope->find_genvar((*cur).first)) {
-		  cerr << cur->second.get_fileline()
-		       << ": error: localparam and genvar in '"
-		       << scope->fullname() << "' have the same name '"
-		       << (*cur).first << "'." << endl;
-		  des->errors += 1;
-	    }
-
-	    collect_parm_item_(des, scope, (*cur).first, (*cur).second, false, true);
       }
 }
 
 static void collect_scope_specparams_(Design*des, NetScope*scope,
-      const map<perm_string,LexicalScope::param_expr_t>&specparams)
+      const map<perm_string,LexicalScope::param_expr_t*>&specparams)
 {
       for (mparm_it_t cur = specparams.begin()
 		 ; cur != specparams.end() ;  ++ cur ) {
 
-	      // A specparam can not have the same name as a genvar.
+	    collect_parm_item_(des, scope, cur->first, *(cur->second), true, false);
-	    if (scope->find_genvar((*cur).first)) {
-		  cerr << cur->second.get_fileline()
-		       << ": error: specparam and genvar in '"
-		       << scope->fullname() << "' have the same name '"
-		       << (*cur).first << "'." << endl;
-		  des->errors += 1;
-	    }
-
-	    collect_parm_item_(des, scope, (*cur).first, (*cur).second, true, false);
       }
 }
 
@@ -556,6 +529,7 @@ static void elaborate_scope_class(Design*des, NetScope*scope, PClass*pclass)
 	      // Task methods are always automatic...
 	    method_scope->is_auto(true);
 	    method_scope->set_line(cur->second);
+	    method_scope->add_imports(&cur->second->explicit_imports);
 
 	    if (debug_scopes) {
 		  cerr << cur->second->get_fileline() << ": elaborate_scope_class: "
@@ -574,6 +548,7 @@ static void elaborate_scope_class(Design*des, NetScope*scope, PClass*pclass)
 	      // Function methods are always automatic...
 	    method_scope->is_auto(true);
 	    method_scope->set_line(cur->second);
+	    method_scope->add_imports(&cur->second->explicit_imports);
 
 	    if (debug_scopes) {
 		  cerr << cur->second->get_fileline() << ": elaborate_scope_class: "
@@ -644,6 +619,7 @@ static void elaborate_scope_task(Design*des, NetScope*scope, PTask*task)
       NetScope*task_scope = new NetScope(scope, use_name, NetScope::TASK);
       task_scope->is_auto(task->is_auto());
       task_scope->set_line(task);
+      task_scope->add_imports(&task->explicit_imports);
 
       if (debug_scopes) {
 	    cerr << task->get_fileline() << ": elaborate_scope_task: "
@@ -661,39 +637,6 @@ static void elaborate_scope_tasks(Design*des, NetScope*scope,
       for (tasks_it_t cur = tasks.begin()
 		 ; cur != tasks.end() ;  ++ cur ) {
 
-	    hname_t use_name( (*cur).first );
-	      // A task can not have the same name as another scope object.
-	    const NetScope *child = scope->child(use_name);
-	    if (child) {
-		  cerr << cur->second->get_fileline() << ": error: task and ";
-		  child->print_type(cerr);
-		  cerr << " in '" << scope->fullname()
-		       << "' have the same name '" << use_name << "'." << endl;
-		  des->errors += 1;
-		  continue;
-	    }
-
-	      // A task can not have the same name as a genvar.
-	    if (scope->find_genvar((*cur).first)) {
-		  cerr << cur->second->get_fileline()
-		       << ": error: task and genvar in '"
-		       << scope->fullname() << "' have the same name '"
-		       << (*cur).first << "'." << endl;
-		  des->errors += 1;
-	    }
-
-	      // A task can not have the same name as a parameter.
-	    const NetExpr *ex_msb, *ex_lsb;
-	    const NetExpr *parm = scope->get_parameter(des, (*cur).first,
-                                                       ex_msb, ex_lsb);
-	    if (parm) {
-		  cerr << cur->second->get_fileline()
-		       << ": error: task and parameter in '"
-		       << scope->fullname() << "' have the same name '"
-		       << (*cur).first << "'." << endl;
-		  des->errors += 1;
-	    }
-
 	    elaborate_scope_task(des, scope, cur->second);
       }
 
@@ -706,6 +649,7 @@ static void elaborate_scope_func(Design*des, NetScope*scope, PFunction*task)
       NetScope*task_scope = new NetScope(scope, use_name, NetScope::FUNC);
       task_scope->is_auto(task->is_auto());
       task_scope->set_line(task);
+      task_scope->add_imports(&task->explicit_imports);
 
       if (debug_scopes) {
 	    cerr << task->get_fileline() << ": elaborate_scope_func: "
@@ -723,40 +667,6 @@ static void elaborate_scope_funcs(Design*des, NetScope*scope,
       for (funcs_it_t cur = funcs.begin()
 		 ; cur != funcs.end() ;  ++ cur ) {
 
-	    hname_t use_name( (*cur).first );
-	      // A function can not have the same name as another scope object.
-	    const NetScope *child = scope->child(use_name);
-	    if (child) {
-		  cerr << cur->second->get_fileline()
-		       << ": error: function and ";
-		  child->print_type(cerr);
-		  cerr << " in '" << scope->fullname()
-		       << "' have the same name '" << use_name << "'." << endl;
-		  des->errors += 1;
-		  continue;
-	    }
-
-	      // A function can not have the same name as a genvar.
-	    if (scope->find_genvar((*cur).first)) {
-		  cerr << cur->second->get_fileline()
-		       << ": error: function and genvar in '"
-		       << scope->fullname() << "' have the same name '"
-		       << (*cur).first << "'." << endl;
-		  des->errors += 1;
-	    }
-
-	      // A function can not have the same name as a parameter.
-	    const NetExpr *ex_msb, *ex_lsb;
-	    const NetExpr *parm = scope->get_parameter(des, (*cur).first,
-                                                       ex_msb, ex_lsb);
-	    if (parm) {
-		  cerr << cur->second->get_fileline()
-		       << ": error: function and parameter in '"
-		       << scope->fullname() << "' have the same name '"
-		       << (*cur).first << "'." << endl;
-		  des->errors += 1;
-	    }
-
 	    elaborate_scope_func(des, scope, cur->second);
       }
 
@@ -815,6 +725,7 @@ bool PPackage::elaborate_scope(Design*des, NetScope*scope)
       elaborate_scope_classes(des, scope, classes_lexical);
       elaborate_scope_funcs(des, scope, funcs);
       elaborate_scope_tasks(des, scope, tasks);
+      elaborate_scope_events_(des, scope, events);
       return true;
 }
 
@@ -1013,56 +924,6 @@ bool PGenerate::generate_scope_loop_(Design*des, NetScope*container)
 	    return false;
       }
 
-	// Check the generate block name.
-
-	// A generate "loop" can not have the same name as another
-	// scope object. Find any scope with this name, not just an
-	// exact match scope.
-      const NetScope *child = container->child_byname(scope_name);
-      if (child) {
-	    cerr << get_fileline() << ": error: generate \"loop\" and ";
-	    child->print_type(cerr);
-	    cerr << " in '" << container->fullname()
-	         << "' have the same name '" << scope_name << "'." << endl;
-	    des->errors += 1;
-	    return false;
-      }
-
-	// A generate "loop" can not have the same name as a genvar.
-      if (container->find_genvar(scope_name)) {
-	    cerr << get_fileline() << ": error: generate \"loop\" and "
-	            "genvar in '" << container->fullname()
-	         << "' have the same name '" << scope_name << "'." << endl;
-	    des->errors += 1;
-      }
-
-	// A generate "loop" can not have the same name as a named event.
-      const NetEvent *event = container->find_event(scope_name);
-      if (event) {
-	    cerr << get_fileline() << ": error: generate \"loop\" and "
-	            "named event in '" << container->fullname()
-	         << "' have the same name '" << scope_name << "'." << endl;
-	    des->errors += 1;
-      }
-
-	// A generate "loop" can not have the same name as a parameter.
-      const NetExpr*tmsb;
-      const NetExpr*tlsb;
-      const NetExpr*texpr = container->get_parameter(des, scope_name,
-                                                     tmsb, tlsb);
-      if (texpr != 0) {
-	    cerr << get_fileline() << ": error: generate \"loop\" and "
-	            "parameter in '" << container->fullname()
-	         << "' have the same name '" << scope_name << "'." << endl;
-	    des->errors += 1;
-      }
-
-	// These have all been checked so we just need to skip the actual
-	// generation for these name conflicts. Not skipping these two will
-	// cause the compiler to have problems (assert, inf. loop, etc.).
-      if (container->get_parameter(des, loop_index, tmsb, tlsb)) return false;
-      if (container->find_event(loop_index)) return false;
-
       genvar = init->value().as_long();
       delete init_ex;
 
@@ -1093,6 +954,7 @@ bool PGenerate::generate_scope_loop_(Design*des, NetScope*container)
 	    NetScope*scope = new NetScope(container, use_name,
 					  NetScope::GENBLOCK);
 	    scope->set_line(get_file(), get_lineno());
+	    scope->add_imports(&explicit_imports);
 
 	      // Set in the scope a localparam for the value of the
 	      // genvar within this instance of the generate
@@ -1169,45 +1031,6 @@ bool PGenerate::generate_scope_condit_(Design*des, NetScope*container, bool else
       }
 
       hname_t use_name (scope_name);
-	// A generate "if" can not have the same name as another scope object.
-      const NetScope *child = container->child(use_name);
-      if (child) {
-	    cerr << get_fileline() << ": error: generate \"if\" and ";
-	    child->print_type(cerr);
-	    cerr << " in '" << container->fullname()
-	         << "' have the same name '" << use_name << "'." << endl;
-	    des->errors += 1;
-	    return false;
-      }
-
-	// A generate "if" can not have the same name as a genvar.
-      if (container->find_genvar(scope_name)) {
-	    cerr << get_fileline() << ": error: generate \"if\" and "
-	            "genvar in '" << container->fullname()
-	         << "' have the same name '" << scope_name << "'." << endl;
-	    des->errors += 1;
-      }
-
-	// A generate "if" can not have the same name as a named event.
-      const NetEvent *event = container->find_event(scope_name);
-      if (event) {
-	    cerr << get_fileline() << ": error: generate \"if\" and "
-	            "named event in '" << container->fullname()
-	         << "' have the same name '" << use_name << "'." << endl;
-	    des->errors += 1;
-      }
-
-	// A generate "if" can not have the same name as a parameter.
-      const NetExpr *ex_msb, *ex_lsb;
-      const NetExpr *parm = container->get_parameter(des, scope_name,
-                                                     ex_msb, ex_lsb);
-      if (parm) {
-	    cerr << get_fileline() << ": error: generate \"if\" and "
-	            "parameter in '" << container->fullname()
-	         << "' have the same name '" << use_name << "'." << endl;
-	    des->errors += 1;
-      }
-
       if (debug_scopes)
 	    cerr << get_fileline() << ": debug: Generate condition "
 		 << (else_flag? "(else)" : "(if)")
@@ -1228,6 +1051,7 @@ bool PGenerate::generate_scope_condit_(Design*des, NetScope*container, bool else
 	// for myself. That is what I will pass to the subscope.
       NetScope*scope = new NetScope(container, use_name, NetScope::GENBLOCK);
       scope->set_line(get_file(), get_lineno());
+      scope->add_imports(&explicit_imports);
 
       elaborate_subscope_(des, scope);
 
@@ -1311,44 +1135,6 @@ bool PGenerate::generate_scope_case_(Design*des, NetScope*container)
 
 	// The name of the scope to generate, whatever that item is.
       hname_t use_name (item->scope_name);
-	// A generate "case" can not have the same name as another scope object.
-      const NetScope *child = container->child(use_name);
-      if (child) {
-	    cerr << get_fileline() << ": error: generate \"case\" and ";
-	    child->print_type(cerr);
-	    cerr << " in '" << container->fullname()
-	         << "' have the same name '" << use_name << "'." << endl;
-	    des->errors += 1;
-	    return false;
-      }
-
-	// A generate "case" can not have the same name as a genvar.
-      if (container->find_genvar(item->scope_name)) {
-	    cerr << get_fileline() << ": error: generate \"case\" and "
-	            "genvar in '" << container->fullname()
-	         << "' have the same name '" << use_name << "'." << endl;
-	    des->errors += 1;
-      }
-
-	// A generate "case" can not have the same name as a named event.
-      const NetEvent *event = container->find_event(item->scope_name);
-      if (event) {
-	    cerr << get_fileline() << ": error: generate \"case\" and "
-	            "named event in '" << container->fullname()
-	         << "' have the same name '" << use_name << "'." << endl;
-	    des->errors += 1;
-      }
-
-	// A generate "case" can not have the same name as a parameter.
-      const NetExpr *ex_msb, *ex_lsb;
-      const NetExpr *parm = container->get_parameter(des, item->scope_name,
-                                                     ex_msb, ex_lsb);
-      if (parm) {
-	    cerr << get_fileline() << ": error: generate \"case\" and "
-	            "parameter in '" << container->fullname()
-	         << "' have the same name '" << use_name << "'." << endl;
-	    des->errors += 1;
-      }
 
       item->probe_for_direct_nesting_();
       if (item->direct_nested_) {
@@ -1368,6 +1154,8 @@ bool PGenerate::generate_scope_case_(Design*des, NetScope*container)
       NetScope*scope = new NetScope(container, use_name,
 				    NetScope::GENBLOCK);
       scope->set_line(get_file(), get_lineno());
+      scope->add_imports(&explicit_imports);
+
       item->elaborate_subscope_(des, scope);
 
       return true;
@@ -1376,46 +1164,6 @@ bool PGenerate::generate_scope_case_(Design*des, NetScope*container)
 bool PGenerate::generate_scope_nblock_(Design*des, NetScope*container)
 {
       hname_t use_name (scope_name);
-	// A generate "block" can not have the same name as another scope
-	// object.
-      const NetScope *child = container->child(use_name);
-      if (child) {
-	    cerr << get_fileline() << ": error: generate \"block\" and ";
-	    child->print_type(cerr);
-	    cerr << " in '" << container->fullname()
-	         << "' have the same name '" << use_name << "'." << endl;
-	    des->errors += 1;
-	    return false;
-      }
-
-	// A generate "block" can not have the same name as a genvar.
-      if (container->find_genvar(scope_name)) {
-	    cerr << get_fileline() << ": error: generate \"block\" and "
-	            "genvar in '" << container->fullname()
-	         << "' have the same name '" << scope_name << "'." << endl;
-	    des->errors += 1;
-      }
-
-	// A generate "block" can not have the same name as a named event.
-      const NetEvent *event = container->find_event(scope_name);
-      if (event) {
-	    cerr << get_fileline() << ": error: generate \"block\" and "
-	            "named event in '" << container->fullname()
-	         << "' have the same name '" << use_name << "'." << endl;
-	    des->errors += 1;
-      }
-
-	// A generate "block" can not have the same name as a parameter.
-      const NetExpr *ex_msb, *ex_lsb;
-      const NetExpr *parm = container->get_parameter(des, scope_name,
-                                                     ex_msb, ex_lsb);
-      if (parm) {
-	    cerr << get_fileline() << ": error: generate \"block\" and "
-	            "parameter in '" << container->fullname()
-	         << "' have the same name '" << use_name << "'." << endl;
-	    des->errors += 1;
-      }
-
       if (debug_scopes)
 	    cerr << get_fileline() << ": debug: Generate named block "
 		 << ": Generate scope=" << use_name << endl;
@@ -1423,6 +1171,7 @@ bool PGenerate::generate_scope_nblock_(Design*des, NetScope*container)
       NetScope*scope = new NetScope(container, use_name,
 				    NetScope::GENBLOCK);
       scope->set_line(get_file(), get_lineno());
+      scope->add_imports(&explicit_imports);
 
       elaborate_subscope_(des, scope);
 
@@ -1554,36 +1303,6 @@ void PGModule::elaborate_scope_mod_(Design*des, Module*mod, NetScope*sc) const
 	// Missing module instance names have already been rejected.
       assert(get_name() != "");
 
-	// A module instance can not have the same name as another scope object.
-      const NetScope *child = sc->child(hname_t(get_name()));
-      if (child) {
-	    cerr << get_fileline() << ": error: module <" << mod->mod_name()
-	         << "> instance and ";
-	    child->print_type(cerr);
-	    cerr << " in '" << sc->fullname()
-	         << "' have the same name '" << get_name() << "'." << endl;
-	    des->errors += 1;
-	    return;
-      }
-
-	// A module instance can not have the same name as a genvar.
-      if (sc->find_genvar(get_name())) {
-	    cerr << get_fileline() << ": error: module <" << mod->mod_name()
-	         << "> instance and genvar in '" << sc->fullname()
-	         << "' have the same name '" << get_name() << "'." << endl;
-	    des->errors += 1;
-      }
-
-	// A module instance can not have the same name as a parameter.
-      const NetExpr *ex_msb, *ex_lsb;
-      const NetExpr *parm = sc->get_parameter(des, get_name(), ex_msb, ex_lsb);
-      if (parm) {
-	    cerr << get_fileline() << ": error: module <" << mod->mod_name()
-	         << "> instance and parameter in '" << sc->fullname()
-	         << "' have the same name '" << get_name() << "'." << endl;
-	    des->errors += 1;
-      }
-
 	// check for recursive instantiation by scanning the current
 	// scope and its parents. Look for a module instantiation of
 	// the same module, but farther up in the scope.
@@ -1728,6 +1447,7 @@ void PGModule::elaborate_scope_mod_instances_(Design*des, Module*mod, NetScope*s
 	    my_scope->set_line(get_file(), mod->get_file(),
 	                       get_lineno(), mod->get_lineno());
 	    my_scope->set_module_name(mod->mod_name());
+	    my_scope->add_imports(&mod->explicit_imports);
 
 	    for (unsigned adx = 0 ;  adx < attrib_list_n ;  adx += 1)
 	      my_scope->attribute(attrib_list[adx].key, attrib_list[adx].val);
@@ -1809,36 +1529,8 @@ void PGModule::elaborate_scope_mod_instances_(Design*des, Module*mod, NetScope*s
  * no hierarchy, but neither does the NetEvent, until it is stored in
  * the NetScope object.
  */
-void PEvent::elaborate_scope(Design*des, NetScope*scope) const
+void PEvent::elaborate_scope(Design*, NetScope*scope) const
 {
-	// A named event can not have the same name as another scope object.
-      const NetScope *child = scope->child(hname_t(name_));
-      if (child) {
-	    cerr << get_fileline() << ": error: named event and ";
-	    child->print_type(cerr);
-	    cerr << " in '" << scope->fullname()
-	         << "' have the same name '" << name_ << "'." << endl;
-	    des->errors += 1;
-      }
-
-	// A named event can not have the same name as a genvar.
-      if (scope->find_genvar(name_)) {
-	    cerr << get_fileline() << ": error: named event and "
-	         << "genvar in '" << scope->fullname()
-	         << "' have the same name '" << name_ << "'." << endl;
-	    des->errors += 1;
-      }
-
-	// A named event can not have the same name as a parameter.
-      const NetExpr *ex_msb, *ex_lsb;
-      const NetExpr *parm = scope->get_parameter(des, name_, ex_msb, ex_lsb);
-      if (parm) {
-	    cerr << get_fileline() << ": error: named event and "
-	         << "parameter in '" << scope->fullname()
-	         << "' have the same name '" << name_ << "'." << endl;
-	    des->errors += 1;
-      }
-
       NetEvent*ev = new NetEvent(name_);
       ev->set_line(*this);
       scope->add_event(ev);
@@ -1909,37 +1601,6 @@ void PBlock::elaborate_scope(Design*des, NetScope*scope) const
 
       if (pscope_name() != 0) {
 	    hname_t use_name(pscope_name());
-	      // A named block can not have the same name as another scope
-	      // object.
-	    const NetScope *child = scope->child(use_name);
-	    if (child) {
-		  cerr << get_fileline() << ": error: named block and ";
-		  child->print_type(cerr);
-		  cerr << " in '" << scope->fullname()
-		       << "' have the same name '" << use_name << "'." << endl;
-		  des->errors += 1;
-		  return;
-	    }
-
-	      // A named block can not have the same name as a genvar.
-	    if (scope->find_genvar(pscope_name())) {
-		  cerr << get_fileline() << ": error: named block and "
-		          "genvar in '" << scope->fullname()
-		       << "' have the same name '" << use_name << "'." << endl;
-		  des->errors += 1;
-	    }
-
-	      // A named block can not have the same name as a parameter.
-	    const NetExpr *ex_msb, *ex_lsb;
-	    const NetExpr *parm = scope->get_parameter(des, pscope_name(),
-                                                       ex_msb, ex_lsb);
-	    if (parm) {
-		  cerr << get_fileline() << ": error: named block and "
-		          "parameter in '" << scope->fullname()
-		       << "' have the same name '" << use_name << "'." << endl;
-		  des->errors += 1;
-	    }
-
 	    if (debug_scopes)
 		  cerr << get_fileline() << ": debug: "
 		       << "Elaborate block scope " << use_name
@@ -1952,6 +1613,7 @@ void PBlock::elaborate_scope(Design*des, NetScope*scope) const
 				    : NetScope::BEGIN_END);
 	    my_scope->set_line(get_file(), get_lineno());
             my_scope->is_auto(scope->is_auto());
+	    my_scope->add_imports(&explicit_imports);
 
 	      // Scan the parameters in the scope, and store the information
 	      // needed to evaluate the parameter expressions.

elab_sig.cc

@@ -942,44 +942,6 @@ NetNet* PWire::elaborate_sig(Design*des, NetScope*scope) const
 
       des->errors += error_cnt_;
 
-	// A signal can not have the same name as a scope object.
-      const NetScope *child = scope->child_byname(name_);
-      if (child) {
-	    cerr << get_fileline() << ": error: signal and ";
-	    child->print_type(cerr);
-	    cerr << " in '" << scope->fullname()
-	         << "' have the same name '" << name_ << "'." << endl;
-	    des->errors += 1;
-      }
-	// A signal can not have the same name as a genvar.
-      const LineInfo *genvar = scope->find_genvar(name_);
-      if (genvar) {
-	    cerr << get_fileline() << ": error: signal and genvar in '"
-	         << scope->fullname() << "' have the same name '" << name_
-	         << "'." << endl;
-	    des->errors += 1;
-      }
-	// A signal can not have the same name as a parameter. Note
-	// that we treat enumeration literals similar to parameters,
-	// so if the name matches an enumeration literal, it will be
-	// caught here.
-      const NetExpr *ex_msb, *ex_lsb;
-      const NetExpr *parm = scope->get_parameter(des, name_, ex_msb, ex_lsb);
-      if (parm) {
-	    cerr << get_fileline() << ": error: signal and parameter in '"
-	         << scope->fullname() << "' have the same name '" << name_
-	         << "'." << endl;
-	    des->errors += 1;
-      }
-	// A signal can not have the same name as a named event.
-      const NetEvent *event = scope->find_event(name_);
-      if (event) {
-	    cerr << get_fileline() << ": error: signal and named event in '"
-	         << scope->fullname() << "' have the same name '" << name_
-	         << "'." << endl;
-	    des->errors += 1;
-      }
-
       if (port_set_ || net_set_) {
 
 	    if (warn_implicit_dimensions
@@ -1214,7 +1176,7 @@ NetNet* PWire::elaborate_sig(Design*des, NetScope*scope) const
 
       } else if (enum_type_t*enum_type = dynamic_cast<enum_type_t*>(set_data_type_)) {
 	    list<named_pexpr_t>::const_iterator sample_name = enum_type->names->begin();
-	    const netenum_t*use_enum = scope->find_enumeration_for_name(sample_name->name);
+	    const netenum_t*use_enum = scope->find_enumeration_for_name(des, sample_name->name);
 
 	    if (debug_elaborate) {
 		  cerr << get_fileline() << ": debug: Create signal " << wtype

elaborate.cc

@@ -4322,7 +4322,13 @@ cerr << endl;
 		  const NetExpr*par = 0;
 		  NetEvent*     eve = 0;
 
-		  NetScope*found_in = symbol_search(this, des, scope,
+		  NetScope*use_scope = scope;
+		  if (id->package()) {
+			use_scope = des->find_package(id->package()->pscope_name());
+			ivl_assert(*this, use_scope);
+		  }
+
+		  NetScope*found_in = symbol_search(this, des, use_scope,
                                                     id->path(),
 						    sig, par, eve);
 
@@ -4368,8 +4374,9 @@ cerr << endl;
 
 	    NetExpr*tmp = elab_and_eval(des, scope, expr_[idx]->expr(), -1);
 	    if (tmp == 0) {
-		  expr_[idx]->dump(cerr);
+		  cerr << get_fileline() << ": error: "
-		  cerr << endl;
+			  "Failed to evaluate event expression '"
+		       << *expr_[idx] << "'." << endl;
 		  des->errors += 1;
 		  continue;
 	    }
@@ -5348,11 +5355,17 @@ NetProc* PTrigger::elaborate(Design*des, NetScope*scope) const
 {
       assert(scope);
 
+      NetScope*use_scope = scope;
+      if (package_) {
+	    use_scope = des->find_package(package_->pscope_name());
+	    ivl_assert(*this, use_scope);
+      }
+
       NetNet*       sig = 0;
       const NetExpr*par = 0;
       NetEvent*     eve = 0;
 
-      NetScope*found_in = symbol_search(this, des, scope, event_,
+      NetScope*found_in = symbol_search(this, des, use_scope, event_,
 					sig, par, eve);
 
       if (found_in == 0) {
@@ -6609,6 +6622,7 @@ Design* elaborate(list<perm_string>roots)
 		  PPackage*unit = pform_units[i];
 		  NetScope*scope = des->make_package_scope(unit->pscope_name(), 0, true);
 		  scope->set_line(unit);
+		  scope->add_imports(&unit->explicit_imports);
 		  set_scope_timescale(des, scope, unit);
 
 		  elaborator_work_item_t*es = new elaborate_package_t(des, scope, unit);
@@ -6633,6 +6647,7 @@ Design* elaborate(list<perm_string>roots)
 	    NetScope*unit_scope = unit_scopes[pac->second->parent_scope()];
 	    NetScope*scope = des->make_package_scope(pac->first, unit_scope, false);
 	    scope->set_line(pac->second);
+	    scope->add_imports(&pac->second->explicit_imports);
 	    set_scope_timescale(des, scope, pac->second);
 
 	    elaborator_work_item_t*es = new elaborate_package_t(des, scope, pac->second);
@@ -6674,6 +6689,7 @@ Design* elaborate(list<perm_string>roots)
 	      // Collect some basic properties of this scope from the
 	      // Module definition.
 	    scope->set_line(rmod);
+	    scope->add_imports(&rmod->explicit_imports);
 	    set_scope_timescale(des, scope, rmod);
 
 	      // Save this scope, along with its definition, in the

lexor.lex

@@ -4,7 +4,7 @@
 
 %{
 /*
- * Copyright (c) 1998-2017 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 1998-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -362,7 +362,7 @@ TU [munpf]
 	/* If this identifier names a previously declared type, then
 	   return this as a TYPE_IDENTIFIER instead. */
       if (rc == IDENTIFIER && gn_system_verilog()) {
-	    if (data_type_t*type = pform_test_type_identifier(yylval.text)) {
+	    if (data_type_t*type = pform_test_type_identifier(yylloc, yylval.text)) {
 		  yylval.type_identifier.text = yylval.text;
 		  yylval.type_identifier.type = type;
 		  rc = TYPE_IDENTIFIER;
@@ -383,7 +383,7 @@ TU [munpf]
 	    }
       }
       if (gn_system_verilog()) {
-	    if (data_type_t*type = pform_test_type_identifier(yylval.text)) {
+	    if (data_type_t*type = pform_test_type_identifier(yylloc, yylval.text)) {
 		  yylval.type_identifier.text = yylval.text;
 		  yylval.type_identifier.type = type;
 		  return TYPE_IDENTIFIER;

net_design.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000-2017 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2000-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -244,7 +244,13 @@ NetScope* Design::find_scope_(NetScope*scope, const std::list<hname_t>&path,
 		    /* Up references may match module name */
 
 	    } else {
-		  scope = scope->child( key );
+		  NetScope*found_scope = scope->child(key);
+		  if (found_scope == 0) {
+			found_scope = scope->find_import(this, key.peek_name());
+			if (found_scope)
+			      found_scope = found_scope->child(key);
+		  }
+		  scope = found_scope;
 		  if (scope == 0) break;
 	    }
 	    tmp.pop_front();
@@ -319,7 +325,13 @@ NetScope* Design::find_scope_(NetScope*scope, const hname_t&path,
 	      /* Up references may match module name */
 	    return scope;
       }
-      return scope->child( path );
+      NetScope*found_scope = scope->child(path);
+      if (found_scope == 0) {
+	    found_scope = scope->find_import(this, path.peek_name());
+	    if (found_scope)
+		  found_scope = found_scope->child(path);
+      }
+      return found_scope;
 }
 
 /*
@@ -864,6 +876,11 @@ NetNet* Design::find_signal(NetScope*scope, pform_name_t path)
 	    if (NetNet*net = scope->find_signal(key))
 		  return net;
 
+	    if (NetScope*import_scope = scope->find_import(this, key)) {
+		  scope = import_scope;
+		  continue;
+	    }
+
 	    if (scope->type() == NetScope::MODULE)
 		  break;
 

net_scope.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000-2017 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2000-2019 Stephen Williams (steve@icarus.com)
  * Copyright (c) 2016 CERN Michele Castellana (michele.castellana@cern.ch)
  *
  *    This source code is free software; you can redistribute it
@@ -25,6 +25,7 @@
 # include  "netclass.h"
 # include  "netenum.h"
 # include  "netvector.h"
+# include  "PPackage.h"
 # include  <cstring>
 # include  <cstdlib>
 # include  <sstream>
@@ -117,6 +118,7 @@ NetScope::NetScope(NetScope*up, const hname_t&n, NetScope::TYPE t, NetScope*in_u
 : type_(t), name_(n), nested_module_(nest), program_block_(program),
   is_interface_(interface), is_unit_(compilation_unit), unit_(in_unit), up_(up)
 {
+      imports_ = 0;
       events_ = 0;
       lcounter_ = 0;
       is_auto_ = false;
@@ -205,16 +207,38 @@ void NetScope::set_line(perm_string file, perm_string def_file,
       def_lineno_ = def_lineno;
 }
 
+void NetScope::add_imports(const map<perm_string,PPackage*>*imports)
+{
+      if (!imports->empty())
+	    imports_ = imports;
+}
+
+NetScope*NetScope::find_import(const Design*des, perm_string name)
+{
+      if (imports_ == 0)
+	    return 0;
+
+      map<perm_string,PPackage*>::const_iterator cur = imports_->find(name);
+      if (cur != imports_->end()) {
+            return des->find_package(cur->second->pscope_name());
+      } else
+            return 0;
+}
+
 /*
  * Look for the enumeration in the current scope and any parent scopes.
  */
-const netenum_t*NetScope::find_enumeration_for_name(perm_string name)
+const netenum_t*NetScope::find_enumeration_for_name(const Design*des, perm_string name)
 {
       NetScope *cur_scope = this;
       while (cur_scope) {
 	    NetEConstEnum*tmp = cur_scope->enum_names_[name];
 	    if (tmp) break;
-	    cur_scope = cur_scope->parent();
+	    NetScope*import_scope = cur_scope->find_import(des, name);
+	    if (import_scope)
+		cur_scope = import_scope;
+	    else
+		cur_scope = cur_scope->parent();
 	    if (cur_scope == 0)
 		  cur_scope = unit_;
       }

netlist.h

@@ -77,6 +77,7 @@ class NetEvWait;
 class PClass;
 class PExpr;
 class PFunction;
+class PPackage;
 class PTaskFunc;
 struct enum_type_t;
 class netclass_t;
@@ -942,9 +943,12 @@ class NetScope : public Definitions, public Attrib {
 	   if a unique name couldn't be generated. */
       bool auto_name(const char* prefix, char pad, const char* suffix);
 
+      void add_imports(const map<perm_string,PPackage*>*imports);
+      NetScope*find_import(const Design*des, perm_string name);
+
 	/* Routine to search for the enumeration given a name. It basically
 	 * does what enumeration_for_name() does but searched the hierarchy. */
-      const netenum_t*find_enumeration_for_name(perm_string name);
+      const netenum_t*find_enumeration_for_name(const Design*des, perm_string name);
 
 	/* Parameters exist within a scope, and these methods allow
 	   one to manipulate the set. In these cases, the name is the
@@ -1269,6 +1273,8 @@ class NetScope : public Definitions, public Attrib {
       signed char time_unit_, time_prec_;
       bool time_from_timescale_;
 
+      const map<perm_string,PPackage*>*imports_;
+
       NetEvent *events_;
 
       map<perm_string,LineInfo*> genvars_;

parse.y

@@ -819,12 +819,14 @@ class_declaration_endlabel_opt
 
 class_declaration_extends_opt /* IEEE1800-2005: A.1.2 */
   : K_extends TYPE_IDENTIFIER
-      { $$.type = $2.type;
+      { pform_set_type_referenced(@2, $2.text);
+	$$.type = $2.type;
 	$$.exprs= 0;
 	delete[]$2.text;
       }
   | K_extends TYPE_IDENTIFIER '(' expression_list_with_nuls ')'
-      { $$.type  = $2.type;
+      { pform_set_type_referenced(@2, $2.text);
+	$$.type  = $2.type;
 	$$.exprs = $4;
 	delete[]$2.text;
       }
@@ -1056,6 +1058,9 @@ data_declaration /* IEEE1800-2005: A.2.1.3 */
 	}
 	pform_makewire(@2, 0, str_strength, $3, NetNet::IMPLICIT_REG, data_type);
       }
+  | attribute_list_opt K_event event_variable_list ';'
+      { if ($3) pform_make_events($3, @2.text, @2.first_line);
+      }
   ;
 
 data_type /* IEEE1800-2005: A.2.2.1 */
@@ -1103,7 +1108,8 @@ data_type /* IEEE1800-2005: A.2.2.1 */
 	$$ = tmp;
       }
   | TYPE_IDENTIFIER dimensions_opt
-      { if ($2) {
+      { pform_set_type_referenced(@1, $1.text);
+	if ($2) {
 	      parray_type_t*tmp = new parray_type_t($1.type, $2);
 	      FILE_NAME(tmp, @1);
 	      $$ = tmp;
@@ -1422,8 +1428,7 @@ loop_statement /* IEEE1800-2005: A.6.8 */
 	char for_block_name [64];
 	snprintf(for_block_name, sizeof for_block_name, "$ivl_for_loop%u", for_counter);
 	for_counter += 1;
-	PBlock*tmp = pform_push_block_scope(for_block_name, PBlock::BL_SEQ);
+	PBlock*tmp = pform_push_block_scope(@1, for_block_name, PBlock::BL_SEQ);
-	FILE_NAME(tmp, @1);
 	current_block_stack.push(tmp);
 
 	list<decl_assignment_t*>assign_list;
@@ -1436,7 +1441,7 @@ loop_statement /* IEEE1800-2005: A.6.8 */
       { pform_name_t tmp_hident;
 	tmp_hident.push_back(name_component_t(lex_strings.make($4)));
 
-	PEIdent*tmp_ident = pform_new_ident(tmp_hident);
+	PEIdent*tmp_ident = pform_new_ident(@4, tmp_hident);
 	FILE_NAME(tmp_ident, @4);
 
 	PForStatement*tmp_for = new PForStatement(tmp_ident, $6, $8, $10, $13);
@@ -1484,8 +1489,7 @@ loop_statement /* IEEE1800-2005: A.6.8 */
 	snprintf(for_block_name, sizeof for_block_name, "$ivl_foreach%u", foreach_counter);
 	foreach_counter += 1;
 
-	PBlock*tmp = pform_push_block_scope(for_block_name, PBlock::BL_SEQ);
+	PBlock*tmp = pform_push_block_scope(@1, for_block_name, PBlock::BL_SEQ);
-	FILE_NAME(tmp, @1);
 	current_block_stack.push(tmp);
 
 	pform_make_foreach_declarations(@1, $5);
@@ -1989,7 +1993,8 @@ simple_type_or_string /* IEEE1800-2005: A.2.2.1 */
 	$$ = tmp;
       }
   | TYPE_IDENTIFIER
-      { $$ = $1.type;
+      { pform_set_type_referenced(@1, $1.text);
+	$$ = $1.type;
 	delete[]$1.text;
       }
   | PACKAGE_IDENTIFIER K_SCOPE_RES
@@ -2547,6 +2552,10 @@ block_item_decl
 
   | type_declaration
 
+  /* Blocks can have imports. */
+
+  | package_import_declaration
+
   /* Recover from errors that happen within variable lists. Use the
      trailing semi-colon to resync the parser. */
 
@@ -3176,7 +3185,8 @@ clocking_event_opt /* */
 
 event_control /* A.K.A. clocking_event */
 	: '@' hierarchy_identifier
-		{ PEIdent*tmpi = new PEIdent(*$2);
+		{ PEIdent*tmpi = pform_new_ident(@2, *$2);
+		  FILE_NAME(tmpi, @2);
 		  PEEvent*tmpe = new PEEvent(PEEvent::ANYEDGE, tmpi);
 		  PEventStatement*tmps = new PEventStatement(tmpe);
 		  FILE_NAME(tmps, @1);
@@ -3559,7 +3569,8 @@ expr_primary_or_typename
   /* There are a few special cases (notably $bits argument) where the
      expression may be a type name. Let the elaborator sort this out. */
   | TYPE_IDENTIFIER
-      { PETypename*tmp = new PETypename($1.type);
+      { pform_set_type_referenced(@1, $1.text);
+	PETypename*tmp = new PETypename($1.type);
 	FILE_NAME(tmp,@1);
 	$$ = tmp;
 	delete[]$1.text;
@@ -3612,7 +3623,7 @@ expr_primary
      indexed arrays and part selects */
 
   | hierarchy_identifier
-      { PEIdent*tmp = pform_new_ident(*$1);
+      { PEIdent*tmp = pform_new_ident(@1, *$1);
 	FILE_NAME(tmp, @1);
 	$$ = tmp;
 	delete $1;
@@ -4508,7 +4519,7 @@ atom2_type
      rule to reflect the rules for assignment l-values. */
 lpvalue
   : hierarchy_identifier
-      { PEIdent*tmp = pform_new_ident(*$1);
+      { PEIdent*tmp = pform_new_ident(@1, *$1);
 	FILE_NAME(tmp, @1);
 	$$ = tmp;
 	delete $1;
@@ -5048,29 +5059,27 @@ module_item
               IDENTIFIER '=' expression ')'
       { pform_start_generate_for(@1, $3, $5, $7, $9, $11); }
     generate_block
-      { pform_endgenerate(); }
+      { pform_endgenerate(false); }
 
   | generate_if
     generate_block_opt
     K_else
       { pform_start_generate_else(@1); }
     generate_block
-      { pform_endgenerate(); }
+      { pform_endgenerate(true); }
 
   | generate_if
     generate_block_opt %prec less_than_K_else
-      { pform_endgenerate(); }
+      { pform_endgenerate(true); }
 
   | K_case '(' expression ')'
       { pform_start_generate_case(@1, $3); }
     generate_case_items
     K_endcase
-      { pform_endgenerate(); }
+      { pform_endgenerate(true); }
 
   | modport_declaration
 
-  | package_import_declaration
-
   /* 1364-2001 and later allow specparam declarations outside specify blocks. */
 
   | attribute_list_opt K_specparam
@@ -5162,9 +5171,9 @@ generate_case_items
 
 generate_case_item
   : expression_list_proper ':' { pform_generate_case_item(@1, $1); } generate_block_opt
-      { pform_endgenerate(); }
+      { pform_endgenerate(false); }
   | K_default ':' { pform_generate_case_item(@1, 0); } generate_block_opt
-      { pform_endgenerate(); }
+      { pform_endgenerate(false); }
   ;
 
 generate_item
@@ -5185,7 +5194,7 @@ generate_item
 	      warn_count += 1;
 	      cerr << @1 << ": warning: Anachronistic use of named begin/end to surround generate schemes." << endl;
 	}
-	pform_endgenerate();
+	pform_endgenerate(false);
       }
   ;
 
@@ -5318,7 +5327,8 @@ param_type
 	param_active_type = IVL_VT_BOOL;
       }
   | TYPE_IDENTIFIER
-      { pform_set_param_from_type(@1, $1.type, $1.text, param_active_range,
+      { pform_set_type_referenced(@1, $1.text);
+	pform_set_param_from_type(@1, $1.type, $1.text, param_active_range,
 	                          param_active_signed, param_active_type);
 	delete[]$1.text;
       }
@@ -6260,8 +6270,7 @@ statement_item /* This is roughly statement_item in the LRM */
       }
   /* In SystemVerilog an unnamed block can contain variable declarations. */
   | K_begin
-      { PBlock*tmp = pform_push_block_scope(0, PBlock::BL_SEQ);
+      { PBlock*tmp = pform_push_block_scope(@1, 0, PBlock::BL_SEQ);
-	FILE_NAME(tmp, @1);
 	current_block_stack.push(tmp);
       }
     block_item_decls_opt
@@ -6295,8 +6304,7 @@ statement_item /* This is roughly statement_item in the LRM */
 	$$ = tmp;
       }
   | K_begin ':' IDENTIFIER
-      { PBlock*tmp = pform_push_block_scope($3, PBlock::BL_SEQ);
+      { PBlock*tmp = pform_push_block_scope(@1, $3, PBlock::BL_SEQ);
-	FILE_NAME(tmp, @1);
 	current_block_stack.push(tmp);
       }
     block_item_decls_opt
@@ -6333,8 +6341,7 @@ statement_item /* This is roughly statement_item in the LRM */
       }
   /* In SystemVerilog an unnamed block can contain variable declarations. */
   | K_fork
-      { PBlock*tmp = pform_push_block_scope(0, PBlock::BL_PAR);
+      { PBlock*tmp = pform_push_block_scope(@1, 0, PBlock::BL_PAR);
-	FILE_NAME(tmp, @1);
 	current_block_stack.push(tmp);
       }
     block_item_decls_opt
@@ -6369,8 +6376,7 @@ statement_item /* This is roughly statement_item in the LRM */
 	$$ = tmp;
       }
   | K_fork ':' IDENTIFIER
-      { PBlock*tmp = pform_push_block_scope($3, PBlock::BL_PAR);
+      { PBlock*tmp = pform_push_block_scope(@1, $3, PBlock::BL_PAR);
-	FILE_NAME(tmp, @1);
 	current_block_stack.push(tmp);
       }
     block_item_decls_opt
@@ -6408,12 +6414,18 @@ statement_item /* This is roughly statement_item in the LRM */
 		  FILE_NAME(tmp, @1);
 		  $$ = tmp;
 		}
-	| K_TRIGGER hierarchy_identifier ';'
+  | K_TRIGGER hierarchy_identifier ';'
-		{ PTrigger*tmp = new PTrigger(*$2);
+      { PTrigger*tmp = pform_new_trigger(@2, 0, *$2);
-		  FILE_NAME(tmp, @1);
+	FILE_NAME(tmp, @1);
-		  delete $2;
+	delete $2;
-		  $$ = tmp;
+	$$ = tmp;
-		}
+      }
+  | K_TRIGGER PACKAGE_IDENTIFIER K_SCOPE_RES hierarchy_identifier
+      { PTrigger*tmp = pform_new_trigger(@4, $2, *$4);
+	FILE_NAME(tmp, @1);
+	delete $4;
+	$$ = tmp;
+      }
 
   | procedural_assertion_statement { $$ = $1; }
 

parse_misc.h

@@ -1,7 +1,7 @@
 #ifndef IVL_parse_misc_H
 #define IVL_parse_misc_H
 /*
- * Copyright (c) 1998-2017 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 1998-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -88,7 +88,7 @@ extern void lex_in_package_scope(PPackage*pkg);
  * parser detects typedefs and marks the typedef'ed identifiers as
  * type names.
  */
-extern data_type_t* pform_test_type_identifier(const char*txt);
+extern data_type_t* pform_test_type_identifier(const YYLTYPE&loc, const char*txt);
 extern data_type_t* pform_test_type_identifier(PPackage*pkg, const char*txt);
 
 extern bool pform_test_type_identifier_local(perm_string txt);

pform.cc

@@ -349,6 +349,13 @@ static unsigned scope_generate_counter = 1;
      always within a module. */
 static PGenerate*pform_cur_generate = 0;
 
+  /* Blocks within the same conditional generate construct may have
+     the same name. Here we collect the set of names used in each
+     construct, so they can be added to the local scope without
+     conflicting with each other. Generate constructs may nest, so
+     we need a stack. */
+static list<set<perm_string>> conditional_block_names;
+
   /* This tracks the current modport list being processed. This is
      always within an interface. */
 static PModport*pform_cur_modport = 0;
@@ -400,8 +407,17 @@ LexicalScope* pform_peek_scope(void)
 
 void pform_pop_scope()
 {
-      assert(lexical_scope);
+      LexicalScope*scope = lexical_scope;
-      lexical_scope = lexical_scope->parent_scope();
+      assert(scope);
+
+      map<perm_string,PPackage*>::const_iterator cur;
+      for (cur = scope->possible_imports.begin(); cur != scope->possible_imports.end(); ++cur) {
+            if (scope->local_symbols.find(cur->first) == scope->local_symbols.end())
+                  scope->explicit_imports[cur->first] = cur->second;
+      }
+      scope->possible_imports.clear();
+
+      lexical_scope = scope->parent_scope();
       assert(lexical_scope);
 }
 
@@ -423,6 +439,89 @@ static PScopeExtra* find_nearest_scopex(LexicalScope*scope)
       return scopex;
 }
 
+static void add_local_symbol(LexicalScope*scope, perm_string name, PNamedItem*item)
+{
+      assert(scope);
+
+	// Check for conflict with another local symbol.
+      map<perm_string,PNamedItem*>::const_iterator cur_sym
+	    = scope->local_symbols.find(name);
+      if (cur_sym != scope->local_symbols.end()) {
+	    cerr << item->get_fileline() << ": error: "
+		    "'" << name << "' has already been declared "
+		    "in this scope." << endl;
+	    cerr << cur_sym->second->get_fileline() << ":      : "
+		    "It was declared here as "
+		 << cur_sym->second->symbol_type() << "." << endl;
+	    error_count += 1;
+	    return;
+      }
+
+	// Check for conflict with an explicit import.
+      map<perm_string,PPackage*>::const_iterator cur_pkg
+	    = scope->explicit_imports.find(name);
+      if (cur_pkg != scope->explicit_imports.end()) {
+	    cerr << item->get_fileline() << ": error: "
+		    "'" << name << "' has already been "
+		    "imported into this scope from package '"
+		 << cur_pkg->second->pscope_name() << "'." << endl;
+	    error_count += 1;
+	    return;
+      }
+
+      scope->local_symbols[name] = item;
+}
+
+static PPackage*find_potential_import(const struct vlltype&loc, LexicalScope*scope,
+				      perm_string name, bool tf_call, bool make_explicit)
+{
+      assert(scope);
+
+      PPackage*found_pkg = 0;
+      for (set<PPackage*>::const_iterator cur_pkg = scope->potential_imports.begin();
+	      cur_pkg != scope->potential_imports.end(); ++cur_pkg) {
+	    PPackage*search_pkg = *cur_pkg;
+	    map<perm_string,PNamedItem*>::const_iterator cur_sym
+		= search_pkg->local_symbols.find(name);
+	    if (cur_sym != search_pkg->local_symbols.end()) {
+		  if (found_pkg && make_explicit) {
+			cerr << loc.get_fileline() << ": error: "
+				"Ambiguous use of '" << name << "'. "
+				"It is exported by both '"
+			      << found_pkg->pscope_name()
+			      << "' and by '"
+			      << search_pkg->pscope_name()
+			      << "'." << endl;
+			error_count += 1;
+		  } else {
+			found_pkg = search_pkg;
+			if (make_explicit) {
+                              if (tf_call)
+			            scope->possible_imports[name] = found_pkg;
+                              else
+			            scope->explicit_imports[name] = found_pkg;
+                        }
+		  }
+	    }
+      }
+      return found_pkg;
+}
+
+static void check_potential_imports(const struct vlltype&loc, perm_string name, bool tf_call)
+{
+      LexicalScope*scope = lexical_scope;
+      while (scope) {
+	    if (scope->local_symbols.find(name) != scope->local_symbols.end())
+		  return;
+	    if (scope->explicit_imports.find(name) != scope->explicit_imports.end())
+		  return;
+	    if (find_potential_import(loc, scope, name, tf_call, true))
+		  return;
+
+	    scope = scope->parent_scope();
+      }
+}
+
 /*
  * Set the local time unit/precision. This version is used for setting
  * the time scale for design elements (modules, packages, etc.) and is
@@ -516,12 +615,6 @@ PClass* pform_push_class_scope(const struct vlltype&loc, perm_string name,
 
       pform_set_scope_timescale(class_scope, scopex);
 
-      if (scopex->classes.find(name) != scopex->classes.end()) {
-	    cerr << class_scope->get_fileline() << ": error: duplicate "
-		  "definition for class '" << name << "' in '"
-		 << scopex->pscope_name() << "'." << endl;
-	    error_count += 1;
-      }
       scopex->classes[name] = class_scope;
       scopex->classes_lexical .push_back(class_scope);
 
@@ -566,25 +659,11 @@ PTask* pform_push_task_scope(const struct vlltype&loc, char*name,
       pform_set_scope_timescale(task, scopex);
 
       if (pform_cur_generate) {
-	      // Check if the task is already in the dictionary.
+	    add_local_symbol(pform_cur_generate, task_name, task);
-	    if (pform_cur_generate->tasks.find(task->pscope_name()) !=
+	    pform_cur_generate->tasks[task_name] = task;
-	        pform_cur_generate->tasks.end()) {
-		  cerr << task->get_fileline() << ": error: duplicate "
-		          "definition for task '" << name << "' in '"
-		       << pform_cur_module.front()->mod_name() << "' (generate)."
-		       << endl;
-		  error_count += 1;
-	    }
-	    pform_cur_generate->tasks[task->pscope_name()] = task;
       } else {
-	      // Check if the task is already in the dictionary.
+	    add_local_symbol(scopex, task_name, task);
-	    if (scopex->tasks.find(task->pscope_name()) != scopex->tasks.end()) {
+	    scopex->tasks[task_name] = task;
-		  cerr << task->get_fileline() << ": error: duplicate "
-		          "definition for task '" << name << "' in '"
-		       << scopex->pscope_name() << "'." << endl;
-		  error_count += 1;
-	    }
-	    scopex->tasks[task->pscope_name()] = task;
       }
 
       lexical_scope = task;
@@ -615,26 +694,12 @@ PFunction* pform_push_function_scope(const struct vlltype&loc, const char*name,
       pform_set_scope_timescale(func, scopex);
 
       if (pform_cur_generate) {
-	      // Check if the function is already in the dictionary.
+	    add_local_symbol(pform_cur_generate, func_name, func);
-	    if (pform_cur_generate->funcs.find(func->pscope_name()) !=
+	    pform_cur_generate->funcs[func_name] = func;
-	        pform_cur_generate->funcs.end()) {
-		  cerr << func->get_fileline() << ": error: duplicate "
-		          "definition for function '" << name << "' in '"
-		       << pform_cur_module.front()->mod_name() << "' (generate)."
-		       << endl;
-		  error_count += 1;
-	    }
-	    pform_cur_generate->funcs[func->pscope_name()] = func;
 
       } else {
-	      // Check if the function is already in the dictionary.
+	    add_local_symbol(scopex, func_name, func);
-	    if (scopex->funcs.find(func->pscope_name()) != scopex->funcs.end()) {
+	    scopex->funcs[func_name] = func;
-		  cerr << func->get_fileline() << ": error: duplicate "
-		          "definition for function '" << name << "' in '"
-		       << scopex->pscope_name() << "'." << endl;
-		  error_count += 1;
-	    }
-	    scopex->funcs[func->pscope_name()] = func;
       }
 
       lexical_scope = func;
@@ -642,7 +707,8 @@ PFunction* pform_push_function_scope(const struct vlltype&loc, const char*name,
       return func;
 }
 
-PBlock* pform_push_block_scope(char*name, PBlock::BL_TYPE bt)
+PBlock* pform_push_block_scope(const struct vlltype&loc, char*name,
+			       PBlock::BL_TYPE bt)
 {
       perm_string block_name;
       if (name) block_name = lex_strings.make(name);
@@ -656,26 +722,34 @@ PBlock* pform_push_block_scope(char*name, PBlock::BL_TYPE bt)
       }
 
       PBlock*block = new PBlock(block_name, lexical_scope, bt);
+      FILE_NAME(block, loc);
       block->default_lifetime = find_lifetime(LexicalScope::INHERITED);
+      if (name) add_local_symbol(lexical_scope, block_name, block);
       lexical_scope = block;
 
       return block;
 }
 
 /*
- * Create a new identifier. Check if this is an imported name.
+ * Create a new identifier.
  */
-PEIdent* pform_new_ident(const pform_name_t&name)
+PEIdent* pform_new_ident(const struct vlltype&loc, const pform_name_t&name)
 {
-      LexicalScope*scope = pform_peek_scope();
+      if (gn_system_verilog())
-      map<perm_string,PPackage*>::const_iterator pkg = scope->imports.find(name.front().name);
+	    check_potential_imports(loc, name.front().name, false);
-      if (pkg == scope->imports.end())
-	    return new PEIdent(name);
 
-	// XXXX For now, do not support indexed imported names.
+      return new PEIdent(name);
-      assert(name.back().index.size() == 0);
+}
 
-      return new PEIdent(pkg->second, name);
+PTrigger* pform_new_trigger(const struct vlltype&loc, PPackage*pkg,
+			    const pform_name_t&name)
+{
+      if (gn_system_verilog())
+	    check_potential_imports(loc, name.front().name, false);
+
+      PTrigger*tmp = new PTrigger(pkg, name);
+      FILE_NAME(tmp, loc);
+      return tmp;
 }
 
 PGenerate* pform_parent_generate(void)
@@ -729,15 +803,33 @@ PWire*pform_get_wire_in_scope(perm_string name)
 
 static void pform_put_wire_in_scope(perm_string name, PWire*net)
 {
+      add_local_symbol(lexical_scope, name, net);
       lexical_scope->wires[name] = net;
 }
 
 static void pform_put_enum_type_in_scope(enum_type_t*enum_set)
 {
+      if (lexical_scope->enum_sets.count(enum_set))
+            return;
+
+      set<perm_string> enum_names;
+      list<named_pexpr_t>::const_iterator cur;
+      for (cur = enum_set->names->begin(); cur != enum_set->names->end(); ++cur) {
+	    if (enum_names.count(cur->name)) {
+		  cerr << enum_set->get_fileline() << ": error: "
+			  "Duplicate enumeration name '"
+		       << cur->name << "'." << endl;
+		  error_count += 1;
+	    } else {
+		  add_local_symbol(lexical_scope, cur->name, enum_set);
+		  enum_names.insert(cur->name);
+	    }
+      }
+
       lexical_scope->enum_sets.insert(enum_set);
 }
 
-PWire*pform_get_make_wire_in_scope(const struct vlltype&li, perm_string name,
+PWire*pform_get_make_wire_in_scope(const struct vlltype&, perm_string name,
                                    NetNet::Type net_type, NetNet::PortType port_type,
                                    ivl_variable_type_t vt_type)
 {
@@ -745,15 +837,11 @@ PWire*pform_get_make_wire_in_scope(const struct vlltype&li, perm_string name,
 
 	// If the wire already exists and is fully defined, this
 	// must be a redeclaration. Start again with a new wire.
-      if (cur && cur->get_data_type() != IVL_VT_NO_TYPE) {
+	// The error will be reported when we add the new wire
-	    LineInfo tloc;
+	// to the scope. Do not delete the old wire - it will
-	    FILE_NAME(&tloc, li);
+	// remain in the local symbol map.
-	    cerr << tloc.get_fileline() << ": error: duplicate declaration "
+      if (cur && cur->get_data_type() != IVL_VT_NO_TYPE)
-	            "for net or variable '" << name << "'." << endl;
-	    error_count += 1;
-	    delete cur;
             cur = 0;
-      }
 
       if (cur == 0) {
 	    cur = new PWire(name, net_type, port_type, vt_type);
@@ -773,17 +861,24 @@ void pform_set_typedef(perm_string name, data_type_t*data_type, std::list<pform_
       if(unp_ranges)
 	    data_type = new uarray_type_t(data_type, unp_ranges);
 
+      add_local_symbol(lexical_scope, name, data_type);
+
       data_type_t*&ref = lexical_scope->typedefs[name];
 
       ivl_assert(*data_type, ref == 0);
       ref = data_type;
 
-      if (enum_type_t*enum_type = dynamic_cast<enum_type_t*>(data_type)) {
+      if (enum_type_t*enum_type = dynamic_cast<enum_type_t*>(data_type))
 	    pform_put_enum_type_in_scope(enum_type);
-      }
 }
 
-data_type_t* pform_test_type_identifier(const char*txt)
+void pform_set_type_referenced(const struct vlltype&loc, const char*name)
+{
+      perm_string lex_name = lex_strings.make(name);
+      check_potential_imports(loc, lex_name, false);
+}
+
+data_type_t* pform_test_type_identifier(const struct vlltype&loc, const char*txt)
 {
       perm_string name = lex_strings.make(txt);
 
@@ -798,8 +893,8 @@ data_type_t* pform_test_type_identifier(const char*txt)
 	      // the name has at least shadowed any other possible
 	      // meaning for this name.
 	    map<perm_string,PPackage*>::iterator cur_pkg;
-	    cur_pkg = cur_scope->imports.find(name);
+	    cur_pkg = cur_scope->explicit_imports.find(name);
-	    if (cur_pkg != cur_scope->imports.end()) {
+	    if (cur_pkg != cur_scope->explicit_imports.end()) {
 		  PPackage*pkg = cur_pkg->second;
 		  cur = pkg->typedefs.find(name);
 		  if (cur != pkg->typedefs.end())
@@ -813,6 +908,16 @@ data_type_t* pform_test_type_identifier(const char*txt)
 	    if (cur != cur_scope->typedefs.end())
 		  return cur->second;
 
+            PPackage*pkg = find_potential_import(loc, cur_scope, name, false, false);
+            if (pkg) {
+	          cur = pkg->typedefs.find(name);
+	          if (cur != cur_scope->typedefs.end())
+		        return cur->second;
+
+		    // Not a type. Give up.
+		  return 0;
+            }
+
 	    cur_scope = cur_scope->parent_scope();
       } while (cur_scope);
 
@@ -841,29 +946,10 @@ PECallFunction* pform_make_call_function(const struct vlltype&loc,
 					 const pform_name_t&name,
 					 const list<PExpr*>&parms)
 {
-      PECallFunction*tmp = 0;
+      if (gn_system_verilog())
-
+	    check_potential_imports(loc, name.front().name, true);
-	// First try to get the function name from a package. Check
-	// the imports, and if the name is there, make the function as
-	// a package member.
-      do {
-	    if (name.size() != 1)
-		  break;
-
-	    perm_string use_name = peek_tail_name(name);
-
-	    map<perm_string,PPackage*>::iterator cur_pkg;
-	    cur_pkg = lexical_scope->imports.find(use_name);
-	    if (cur_pkg == lexical_scope->imports.end())
-		  break;
-
-	    tmp = new PECallFunction(cur_pkg->second, use_name, parms);
-      } while(0);
-
-      if (tmp == 0) {
-	    tmp = new PECallFunction(name, parms);
-      }
 
+      PECallFunction*tmp = new PECallFunction(name, parms);
       FILE_NAME(tmp, loc);
       return tmp;
 }
@@ -872,26 +958,10 @@ PCallTask* pform_make_call_task(const struct vlltype&loc,
 				const pform_name_t&name,
 				const list<PExpr*>&parms)
 {
-      PCallTask*tmp = 0;
+      if (gn_system_verilog())
-
+	    check_potential_imports(loc, name.front().name, true);
-      do {
-	    if (name.size() != 1)
-		  break;
-
-	    perm_string use_name = peek_tail_name(name);
-
-	    map<perm_string,PPackage*>::iterator cur_pkg;
-	    cur_pkg = lexical_scope->imports.find(use_name);
-	    if (cur_pkg == lexical_scope->imports.end())
-		  break;
-
-	    tmp = new PCallTask(cur_pkg->second, name, parms);
-      } while (0);
-
-      if (tmp == 0) {
-	    tmp = new PCallTask(name, parms);
-      }
 
+      PCallTask*tmp = new PCallTask(name, parms);
       FILE_NAME(tmp, loc);
       return tmp;
 }
@@ -1273,6 +1343,8 @@ void pform_startmodule(const struct vlltype&loc, const char*name,
       allow_timeunit_decl = true;
       allow_timeprec_decl = true;
 
+      add_local_symbol(lexical_scope, lex_name, cur_module);
+
       lexical_scope = cur_module;
 
 	/* The generate scheme numbering starts with *1*, not
@@ -1356,31 +1428,20 @@ void pform_endmodule(const char*name, bool inside_celldefine,
       pform_pop_scope();
 }
 
-static void pform_add_genvar(const struct vlltype&li, const perm_string&name,
-                             map<perm_string,LineInfo*>&genvars)
-{
-      LineInfo*lni = new LineInfo();
-      FILE_NAME(lni, li);
-      if (genvars.find(name) != genvars.end()) {
-            cerr << lni->get_fileline() << ": error: genvar '"
-		 << name << "' has already been declared." << endl;
-            cerr << genvars[name]->get_fileline()
-                << ":        the previous declaration is here." << endl;
-            error_count += 1;
-            delete lni;
-      } else {
-            genvars[name] = lni;
-      }
-}
-
 void pform_genvars(const struct vlltype&li, list<perm_string>*names)
 {
       list<perm_string>::const_iterator cur;
       for (cur = names->begin(); cur != names->end() ; *cur++) {
-            if (pform_cur_generate)
+	    PGenvar*genvar = new PGenvar();
-                  pform_add_genvar(li, *cur, pform_cur_generate->genvars);
+	    FILE_NAME(genvar, li);
-            else
+
-                  pform_add_genvar(li, *cur, pform_cur_module.front()->genvars);
+	    if (pform_cur_generate) {
+		  add_local_symbol(pform_cur_generate, *cur, genvar);
+		  pform_cur_generate->genvars[*cur] = genvar;
+	    } else {
+		  add_local_symbol(pform_cur_module.front(), *cur, genvar);
+		  pform_cur_module.front()->genvars[*cur] = genvar;
+	    }
       }
 
       delete names;
@@ -1423,6 +1484,8 @@ void pform_start_generate_if(const struct vlltype&li, PExpr*test)
       pform_cur_generate->loop_init = 0;
       pform_cur_generate->loop_test = test;
       pform_cur_generate->loop_step = 0;
+
+      conditional_block_names.push_front(set<perm_string>());
 }
 
 void pform_start_generate_else(const struct vlltype&li)
@@ -1431,7 +1494,7 @@ void pform_start_generate_else(const struct vlltype&li)
       assert(pform_cur_generate->scheme_type == PGenerate::GS_CONDIT);
 
       PGenerate*cur = pform_cur_generate;
-      pform_endgenerate();
+      pform_endgenerate(false);
 
       PGenerate*gen = new PGenerate(lexical_scope, scope_generate_counter++);
       lexical_scope = gen;
@@ -1465,6 +1528,8 @@ void pform_start_generate_case(const struct vlltype&li, PExpr*expr)
       pform_cur_generate->loop_init = 0;
       pform_cur_generate->loop_test = expr;
       pform_cur_generate->loop_step = 0;
+
+      conditional_block_names.push_front(set<perm_string>());
 }
 
 /*
@@ -1487,6 +1552,10 @@ void pform_start_generate_nblock(const struct vlltype&li, char*name)
 
       pform_cur_generate->scope_name = lex_strings.make(name);
       delete[]name;
+
+      add_local_symbol(pform_cur_generate->parent_scope(),
+                       pform_cur_generate->scope_name,
+                       pform_cur_generate);
 }
 
 /*
@@ -1528,14 +1597,36 @@ void pform_generate_block_name(char*name)
 {
       assert(pform_cur_generate != 0);
       assert(pform_cur_generate->scope_name == 0);
-      pform_cur_generate->scope_name = lex_strings.make(name);
+      perm_string scope_name = lex_strings.make(name);
+      pform_cur_generate->scope_name = scope_name;
+
+      if (pform_cur_generate->scheme_type == PGenerate::GS_CONDIT
+       || pform_cur_generate->scheme_type == PGenerate::GS_ELSE
+       || pform_cur_generate->scheme_type == PGenerate::GS_CASE_ITEM) {
+
+            if (conditional_block_names.front().count(scope_name))
+                  return;
+
+            conditional_block_names.front().insert(scope_name);
+      }
+
+      LexicalScope*parent_scope = pform_cur_generate->parent_scope();
+      assert(parent_scope);
+      if (pform_cur_generate->scheme_type == PGenerate::GS_CASE_ITEM)
+	      // Skip over the PGenerate::GS_CASE container.
+	    parent_scope = parent_scope->parent_scope();
+
+      add_local_symbol(parent_scope, scope_name, pform_cur_generate);
 }
 
-void pform_endgenerate()
+void pform_endgenerate(bool end_conditional)
 {
       assert(pform_cur_generate != 0);
       assert(! pform_cur_module.empty());
 
+      if (end_conditional)
+            conditional_block_names.pop_front();
+
 	// If there is no explicit block name then generate a temporary
 	// name. This will be replaced by the correct name later, once
 	// we know all the explicit names in the surrounding scope. If
@@ -2024,18 +2115,10 @@ static void pform_set_net_range(list<perm_string>*names,
  */
 static void pform_make_event(perm_string name, const char*fn, unsigned ln)
 {
-	// Check if the named event is already in the dictionary.
-      if (lexical_scope->events.find(name) != lexical_scope->events.end()) {
-	    LineInfo tloc;
-	    FILE_NAME(&tloc, fn, ln);
-	    cerr << tloc.get_fileline() << ": error: duplicate definition "
-	            "for named event '" << name << "' in '"
-	         << pform_cur_module.front()->mod_name() << "'." << endl;
-	    error_count += 1;
-      }
-
       PEvent*event = new PEvent(name);
       FILE_NAME(event, fn, ln);
+
+      add_local_symbol(lexical_scope, name, event);
       lexical_scope->events[name] = event;
 }
 
@@ -2089,10 +2172,13 @@ static void pform_makegate(PGBuiltin::Type type,
       cur->strength1(str.str1);
       FILE_NAME(cur, info.file, info.lineno);
 
-      if (pform_cur_generate)
+      if (pform_cur_generate) {
+	    if (dev_name != "") add_local_symbol(pform_cur_generate, dev_name, cur);
 	    pform_cur_generate->add_gate(cur);
-      else
+      } else {
+	    if (dev_name != "") add_local_symbol(pform_cur_module.front(), dev_name, cur);
 	    pform_cur_module.front()->add_gate(cur);
+      }
 }
 
 void pform_makegates(const struct vlltype&loc,
@@ -2169,10 +2255,13 @@ static void pform_make_modgate(perm_string type,
 	    cur->set_parameters(overrides->by_order);
       }
 
-      if (pform_cur_generate)
+      if (pform_cur_generate) {
+	    if (name != "") add_local_symbol(pform_cur_generate, name, cur);
 	    pform_cur_generate->add_gate(cur);
-      else
+      } else {
+	    if (name != "") add_local_symbol(pform_cur_module.front(), name, cur);
 	    pform_cur_module.front()->add_gate(cur);
+      }
       pform_bind_attributes(cur->attributes, attr);
 }
 
@@ -2214,11 +2303,13 @@ static void pform_make_modgate(perm_string type,
 	    cur->set_parameters(overrides->by_order);
       }
 
-
+      if (pform_cur_generate) {
-      if (pform_cur_generate)
+	    add_local_symbol(pform_cur_generate, name, cur);
 	    pform_cur_generate->add_gate(cur);
-      else
+      } else {
+	    add_local_symbol(pform_cur_module.front(), name, cur);
 	    pform_cur_module.front()->add_gate(cur);
+      }
       pform_bind_attributes(cur->attributes, attr);
 }
 
@@ -2554,20 +2645,15 @@ static PWire* pform_get_or_make_wire(const vlltype&li, perm_string name,
 
 	// If the wire already exists and is fully defined, this
 	// must be a redeclaration. Start again with a new wire.
-      if (cur) {
+	// The error will be reported when we add the new wire
-	    LineInfo tloc;
+	// to the scope. Do not delete the old wire - it will
-	    FILE_NAME(&tloc, li);
+	// remain in the local symbol map.
-	    cerr << tloc.get_fileline() << ": error: duplicate declaration "
-	            "for net or variable '" << name << "' in '"
-	         << pform_cur_module.front()->mod_name() << "'." << endl;
-	    error_count += 1;
-	    delete cur;
-      }
 
       cur = new PWire(name, type, ptype, dtype);
       FILE_NAME(cur, li.text, li.first_line);
 
       pform_put_wire_in_scope(name, cur);
+
       return cur;
 }
 
@@ -3021,63 +3107,33 @@ void pform_set_parameter(const struct vlltype&loc,
             VLerror("parameter declarations are not permitted in generate blocks");
             return;
       }
-      PScopeExtra*scopex = find_nearest_scopex(lexical_scope);
-      assert(scopex);
-
-	// Check if the parameter name is already in the dictionary.
-      if (scope->parameters.find(name) != scope->parameters.end()) {
-	    LineInfo tloc;
-	    FILE_NAME(&tloc, loc);
-	    cerr << tloc.get_fileline() << ": error: duplicate definition "
-	            "for parameter '" << name << "' in '"
-	         << scopex->pscope_name() << "'." << endl;
-	    error_count += 1;
-      }
-      if (scope->localparams.find(name) != scope->localparams.end()) {
-	    LineInfo tloc;
-	    FILE_NAME(&tloc, loc);
-	    cerr << tloc.get_fileline() << ": error: localparam and "
-		 << "parameter in '" << scopex->pscope_name()
-	         << "' have the same name '" << name << "'." << endl;
-	    error_count += 1;
-      }
-	// Only a Module scope has specparams.
-	  if ((dynamic_cast<Module*> (scope)) &&
-		  (scope == pform_cur_module.front()) &&
-          (pform_cur_module.front()->specparams.find(name) !=
-           pform_cur_module.front()->specparams.end())) {
-	    LineInfo tloc;
-	    FILE_NAME(&tloc, loc);
-	    cerr << tloc.get_fileline() << ": error: specparam and "
-		  "parameter in '" << scopex->pscope_name()
-	         << "' have the same name '" << name << "'." << endl;
-	    error_count += 1;
-      }
 
       assert(expr);
-      Module::param_expr_t&parm = scope->parameters[name];
+      Module::param_expr_t*parm = new Module::param_expr_t();
-      FILE_NAME(&parm, loc);
+      FILE_NAME(parm, loc);
 
-      parm.expr = expr;
+      add_local_symbol(scope, name, parm);
+      scope->parameters[name] = parm;
 
-      parm.type = type;
+      parm->expr = expr;
+
+      parm->type = type;
       if (range) {
 	    assert(range->size() == 1);
 	    pform_range_t&rng = range->front();
 	    assert(rng.first);
 	    assert(rng.second);
-	    parm.msb = rng.first;
+	    parm->msb = rng.first;
-	    parm.lsb = rng.second;
+	    parm->lsb = rng.second;
       } else {
-	    parm.msb = 0;
+	    parm->msb = 0;
-	    parm.lsb = 0;
+	    parm->lsb = 0;
       }
-      parm.signed_flag = signed_flag;
+      parm->signed_flag = signed_flag;
-      parm.range = value_range;
+      parm->range = value_range;
 
 	// Only a Module keeps the position of the parameter.
-	  if ((dynamic_cast<Module*> (scope)) &&
+      if ((dynamic_cast<Module*>(scope)) && (scope == pform_cur_module.front()))
-		  (scope == pform_cur_module.front()))
             pform_cur_module.front()->param_names.push_back(name);
 }
 
@@ -3090,58 +3146,30 @@ void pform_set_localparam(const struct vlltype&loc,
 	    VLerror(loc, "error: localparam declarations must be contained within a module.");
 	    return;
       }
-      PScopeExtra*scopex = find_nearest_scopex(lexical_scope);
-      assert(scopex);
-
-	// Check if the localparam name is already in the dictionary.
-      if (scope->localparams.find(name) != scope->localparams.end()) {
-	    LineInfo tloc;
-	    FILE_NAME(&tloc, loc);
-	    cerr << tloc.get_fileline() << ": error: duplicate definition "
-	            "for localparam '" << name << "' in '"
-	         << scopex->pscope_name() << "'." << endl;
-	    error_count += 1;
-      }
-      if (scope->parameters.find(name) != scope->parameters.end()) {
-	    LineInfo tloc;
-	    FILE_NAME(&tloc, loc);
-	    cerr << tloc.get_fileline() << ": error: parameter and "
-		 << "localparam in '" << scopex->pscope_name()
-	         << "' have the same name '" << name << "'." << endl;
-	    error_count += 1;
-      }
-
-      if ((! pform_cur_module.empty()) &&
-	  (scope == pform_cur_module.front()) &&
-          (pform_cur_module.front()->specparams.find(name) != pform_cur_module.front()->specparams.end())) {
-	    LineInfo tloc;
-	    FILE_NAME(&tloc, loc);
-	    cerr << tloc.get_fileline() << ": error: specparam and "
-		  "localparam in '" << scopex->pscope_name()
-	         << "' have the same name '" << name << "'." << endl;
-	    error_count += 1;
-      }
 
       assert(expr);
-      Module::param_expr_t&parm = scope->localparams[name];
+      Module::param_expr_t*parm = new Module::param_expr_t();
-      FILE_NAME(&parm, loc);
+      FILE_NAME(parm, loc);
 
-      parm.expr = expr;
+      add_local_symbol(scope, name, parm);
+      scope->localparams[name] = parm;
 
-      parm.type = type;
+      parm->expr = expr;
+
+      parm->type = type;
       if (range) {
 	    assert(range->size() == 1);
 	    pform_range_t&rng = range->front();
 	    assert(rng.first);
 	    assert(rng.second);
-	    parm.msb = rng.first;
+	    parm->msb = rng.first;
-	    parm.lsb = rng.second;
+	    parm->lsb = rng.second;
       } else {
-	    parm.msb  = 0;
+	    parm->msb  = 0;
-	    parm.lsb  = 0;
+	    parm->lsb  = 0;
       }
-      parm.signed_flag = signed_flag;
+      parm->signed_flag = signed_flag;
-      parm.range = 0;
+      parm->range = 0;
 }
 
 void pform_set_specparam(const struct vlltype&loc, perm_string name,
@@ -3151,55 +3179,30 @@ void pform_set_specparam(const struct vlltype&loc, perm_string name,
       Module*scope = pform_cur_module.front();
       assert(scope == lexical_scope);
 
-	// Check if the specparam name is already in the dictionary.
-      if (pform_cur_module.front()->specparams.find(name) !=
-          pform_cur_module.front()->specparams.end()) {
-	    LineInfo tloc;
-	    FILE_NAME(&tloc, loc);
-	    cerr << tloc.get_fileline() << ": error: duplicate definition "
-	            "for specparam '" << name << "' in '"
-	         << pform_cur_module.front()->mod_name() << "'." << endl;
-	    error_count += 1;
-      }
-      if (scope->parameters.find(name) != scope->parameters.end()) {
-	    LineInfo tloc;
-	    FILE_NAME(&tloc, loc);
-	    cerr << tloc.get_fileline() << ": error: parameter and "
-		  "specparam in '" << pform_cur_module.front()->mod_name()
-	         << "' have the same name '" << name << "'." << endl;
-	    error_count += 1;
-      }
-      if (scope->localparams.find(name) != scope->localparams.end()) {
-	    LineInfo tloc;
-	    FILE_NAME(&tloc, loc);
-	    cerr << tloc.get_fileline() << ": error: localparam and "
-		  "specparam in '" << pform_cur_module.front()->mod_name()
-	         << "' have the same name '" << name << "'." << endl;
-	    error_count += 1;
-      }
-
       assert(expr);
+      Module::param_expr_t*parm = new Module::param_expr_t();
+      FILE_NAME(parm, loc);
 
-      Module::param_expr_t&parm = pform_cur_module.front()->specparams[name];
+      add_local_symbol(scope, name, parm);
-      FILE_NAME(&parm, loc);
+      pform_cur_module.front()->specparams[name] = parm;
 
-      parm.expr = expr;
+      parm->expr = expr;
 
       if (range) {
 	    assert(range->size() == 1);
 	    pform_range_t&rng = range->front();
 	    assert(rng.first);
 	    assert(rng.second);
-	    parm.type = IVL_VT_LOGIC;
+	    parm->type = IVL_VT_LOGIC;
-	    parm.msb = rng.first;
+	    parm->msb = rng.first;
-	    parm.lsb = rng.second;
+	    parm->lsb = rng.second;
       } else {
-	    parm.type = IVL_VT_NO_TYPE;
+	    parm->type = IVL_VT_NO_TYPE;
-	    parm.msb  = 0;
+	    parm->msb  = 0;
-	    parm.lsb  = 0;
+	    parm->lsb  = 0;
       }
-      parm.signed_flag = false;
+      parm->signed_flag = false;
-      parm.range = 0;
+      parm->range = 0;
 }
 
 void pform_set_defparam(const pform_name_t&name, PExpr*expr)
@@ -3621,12 +3624,10 @@ void pform_start_modport_item(const struct vlltype&loc, const char*name)
       perm_string use_name = lex_strings.make(name);
       pform_cur_modport = new PModport(use_name);
       FILE_NAME(pform_cur_modport, loc);
-      if (scope->modports.find(use_name) != scope->modports.end()) {
+
-	    cerr << loc << ": error: duplicate declaration for modport '"
+      add_local_symbol(scope, use_name, pform_cur_modport);
-		 << name << "' in '" << scope->mod_name() << "'." << endl;
-	    error_count += 1;
-      }
       scope->modports[use_name] = pform_cur_modport;
+
       delete[] name;
 }
 

pform.h

@@ -1,7 +1,7 @@
 #ifndef IVL_pform_H
 #define IVL_pform_H
 /*
- * Copyright (c) 1998-2017 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 1998-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -246,7 +246,10 @@ extern void pform_add_modport_port(const struct vlltype&loc,
  * This creates an identifier aware of names that may have been
  * imported from other packages.
  */
-extern PEIdent* pform_new_ident(const pform_name_t&name);
+extern PEIdent* pform_new_ident(const struct vlltype&loc, const pform_name_t&name);
+
+extern PTrigger* pform_new_trigger(const struct vlltype&loc, PPackage*pkg,
+				   const pform_name_t&name);
 
 /*
  * Enter/exit name scopes. The push_scope function pushes the scope
@@ -274,7 +277,8 @@ extern PTask*pform_push_task_scope(const struct vlltype&loc, char*name,
 extern PFunction*pform_push_function_scope(const struct vlltype&loc, const char*name,
 					   LexicalScope::lifetime_t lifetime);
 
-extern PBlock*pform_push_block_scope(char*name, PBlock::BL_TYPE tt);
+extern PBlock*pform_push_block_scope(const struct vlltype&loc, char*name,
+				     PBlock::BL_TYPE tt);
 
 extern void pform_put_behavior_in_scope(AProcess*proc);
 
@@ -299,7 +303,7 @@ extern void pform_start_generate_case(const struct vlltype&lp, PExpr*test);
 extern void pform_start_generate_nblock(const struct vlltype&lp, char*name);
 extern void pform_generate_case_item(const struct vlltype&lp, list<PExpr*>*test);
 extern void pform_generate_block_name(char*name);
-extern void pform_endgenerate();
+extern void pform_endgenerate(bool end_conditional);
 
 /*
  * This function returns the lexically containing generate scheme, if
@@ -311,9 +315,10 @@ extern PGenerate* pform_parent_generate(void);
 extern void pform_set_typedef(perm_string name, data_type_t*data_type,
 			      std::list<pform_range_t>*unp_ranges);
 
+extern void pform_set_type_referenced(const struct vlltype&loc, const char*name);
+
 /*
- * This function makes a PECallFunction of the named function. Decide
+ * This function makes a PECallFunction of the named function.
- * if this function is in the scope or is imported from a package.
  */
 extern PECallFunction* pform_make_call_function(const struct vlltype&loc,
 						const pform_name_t&name,

pform_dump.cc

@@ -1359,22 +1359,22 @@ void LexicalScope::dump_typedefs_(ostream&out, unsigned indent) const
 
 void LexicalScope::dump_parameters_(ostream&out, unsigned indent) const
 {
-      typedef map<perm_string,param_expr_t>::const_iterator parm_iter_t;
+      typedef map<perm_string,param_expr_t*>::const_iterator parm_iter_t;
       for (parm_iter_t cur = parameters.begin()
 		 ; cur != parameters.end() ; ++ cur ) {
 	    out << setw(indent) << "" << "parameter "
-                << (*cur).second.type << " ";
+                << (*cur).second->type << " ";
-	    if ((*cur).second.signed_flag)
+	    if ((*cur).second->signed_flag)
 		  out << "signed ";
-	    if ((*cur).second.msb)
+	    if ((*cur).second->msb)
-		  out << "[" << *(*cur).second.msb << ":"
+		  out << "[" << *(*cur).second->msb << ":"
-		      << *(*cur).second.lsb << "] ";
+		      << *(*cur).second->lsb << "] ";
 	    out << (*cur).first << " = ";
-	    if ((*cur).second.expr)
+	    if ((*cur).second->expr)
-		  out << *(*cur).second.expr;
+		  out << *(*cur).second->expr;
 	    else
 		  out << "/* ERROR */";
-	    for (LexicalScope::range_t*tmp = (*cur).second.range
+	    for (LexicalScope::range_t*tmp = (*cur).second->range
 		       ; tmp ; tmp = tmp->next) {
 		  if (tmp->exclude_flag)
 			out << " exclude ";
@@ -1408,16 +1408,16 @@ void LexicalScope::dump_parameters_(ostream&out, unsigned indent) const
 
 void LexicalScope::dump_localparams_(ostream&out, unsigned indent) const
 {
-      typedef map<perm_string,param_expr_t>::const_iterator parm_iter_t;
+      typedef map<perm_string,param_expr_t*>::const_iterator parm_iter_t;
       for (parm_iter_t cur = localparams.begin()
 		 ; cur != localparams.end() ; ++ cur ) {
 	    out << setw(indent) << "" << "localparam ";
-	    if ((*cur).second.msb)
+	    if ((*cur).second->msb)
-		  out << "[" << *(*cur).second.msb << ":"
+		  out << "[" << *(*cur).second->msb << ":"
-		      << *(*cur).second.lsb << "] ";
+		      << *(*cur).second->lsb << "] ";
 	    out << (*cur).first << " = ";
-	    if ((*cur).second.expr)
+	    if ((*cur).second->expr)
-		  out << *(*cur).second.expr << ";" << endl;
+		  out << *(*cur).second->expr << ";" << endl;
 	    else
 		  out << "/* ERROR */;" << endl;
       }
@@ -1513,16 +1513,16 @@ void PClass::dump(ostream&out, unsigned indent) const
 
 void Module::dump_specparams_(ostream&out, unsigned indent) const
 {
-      typedef map<perm_string,param_expr_t>::const_iterator parm_iter_t;
+      typedef map<perm_string,param_expr_t*>::const_iterator parm_iter_t;
       for (parm_iter_t cur = specparams.begin()
 		 ; cur != specparams.end() ; ++ cur ) {
 	    out << setw(indent) << "" << "specparam ";
-	    if ((*cur).second.msb)
+	    if ((*cur).second->msb)
-		  out << "[" << *(*cur).second.msb << ":"
+		  out << "[" << *(*cur).second->msb << ":"
-		      << *(*cur).second.lsb << "] ";
+		      << *(*cur).second->lsb << "] ";
 	    out << (*cur).first << " = ";
-	    if ((*cur).second.expr)
+	    if ((*cur).second->expr)
-		  out << *(*cur).second.expr << ";" << endl;
+		  out << *(*cur).second->expr << ";" << endl;
 	    else
 		  out << "/* ERROR */;" << endl;
       }

pform_package.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012-2016 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2012-2019 Stephen Williams (steve@icarus.com)
  * Copyright CERN 2013 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
@@ -72,98 +72,58 @@ void pform_end_package_declaration(const struct vlltype&loc)
  * package is declared in pform ahead of time (it is) and that we can
  * simply transfer definitions to the current scope (we can).
  */
-void pform_package_import(const struct vlltype&, PPackage*pkg, const char*ident)
+void pform_package_import(const struct vlltype&loc, PPackage*pkg, const char*ident)
 {
       LexicalScope*scope = pform_peek_scope();
 
       if (ident) {
 	    perm_string use_ident = lex_strings.make(ident);
 
-	    map<perm_string,LexicalScope::param_expr_t>::const_iterator cur
+	      // Check that the requested symbol is available.
-		  = pkg->parameters.find(use_ident);
+	    map<perm_string,PNamedItem*>::const_iterator cur_sym
-	    if (cur != pkg->parameters.end()) {
+		  = pkg->local_symbols.find(use_ident);
-		  scope->imports[cur->first] = pkg;
+	    if (cur_sym == pkg->local_symbols.end()) {
+		  cerr << loc.get_fileline() << ": error: "
+			  "'" << use_ident << "' is not exported by '"
+		       << pkg->pscope_name() << "'." << endl;
+		  error_count += 1;
 		  return;
 	    }
 
-	    cur = pkg->localparams.find(use_ident);
+	      // Check for conflict with local symbol.
-	    if (cur != pkg->localparams.end()) {
+	    cur_sym = scope->local_symbols.find(use_ident);
-		  scope->imports[cur->first] = pkg;
+	    if (cur_sym != scope->local_symbols.end()) {
+		  cerr << loc.get_fileline() << ": error: "
+			  "'" << use_ident << "' has already been declared "
+			  "in this scope." << endl;
+		  cerr << cur_sym->second->get_fileline() << ":      : "
+			  "It was declared here as "
+		       << cur_sym->second->symbol_type() << "." << endl;
+		  error_count += 1;
 		  return;
 	    }
 
-	    map<perm_string,data_type_t*>::const_iterator tcur;
+	      // Check for conflict with previous import.
-	    tcur = pkg->typedefs.find(use_ident);
+	    map<perm_string,PPackage*>::const_iterator cur_pkg
-	    if (tcur != pkg->typedefs.end()) {
+		  = scope->explicit_imports.find(use_ident);
-		  scope->imports[tcur->first] = pkg;
+	    if (cur_pkg != scope->explicit_imports.end()) {
+		  if (cur_pkg->second != pkg) {
+			cerr << loc.get_fileline() << ": error: "
+				"'" << use_ident << "' has already been "
+				"imported into this scope from package '"
+			     << cur_pkg->second->pscope_name() << "'." << endl;
+			error_count += 1;
+		  }
 		  return;
 	    }
 
-	    map<perm_string,PFunction*>::const_iterator fcur;
+	    scope->explicit_imports[use_ident] = pkg;
-	    fcur = pkg->funcs.find(use_ident);
-	    if (fcur != pkg->funcs.end()) {
-		  scope->imports[fcur->first] = pkg;
-		  return;
-	    }
-
-	    map<perm_string,PTask*>::const_iterator ttcur;
-	    ttcur = pkg->tasks.find(use_ident);
-	    if (ttcur != pkg->tasks.end()) {
-		  scope->imports[ttcur->first] = pkg;
-		  return;
-	    }
-
-	    map<perm_string,PWire*>::const_iterator wcur;
-	    wcur = pkg->wires.find(use_ident);
-	    if (wcur != pkg->wires.end()) {
-		  scope->imports[wcur->first] = pkg;
-		  return;
-	    }
-
-	    ostringstream msg;
-	    msg << "Symbol " << use_ident
-		<< " not found in package " << pkg->pscope_name() << "." << ends;
-	    VLerror(msg.str().c_str());
-	    return;
 
       } else {
-
+	    set<PPackage*>::const_iterator cur_pkg
-	      // Handle the pkg::* case by importing everything from
+		  = scope->potential_imports.find(pkg);
-	      // the package.
+	    if (cur_pkg == scope->potential_imports.end())
-	    for (map<perm_string,LexicalScope::param_expr_t>::const_iterator cur = pkg->parameters.begin()
+		  scope->potential_imports.insert(pkg);
-		       ; cur != pkg->parameters.end() ; ++cur) {
-
-		  scope->imports[cur->first] = pkg;
-	    }
-
-	    for (map<perm_string,LexicalScope::param_expr_t>::const_iterator cur = pkg->localparams.begin()
-		       ; cur != pkg->localparams.end() ; ++cur) {
-
-		  scope->imports[cur->first] = pkg;
-	    }
-
-	    for (map<perm_string,data_type_t*>::const_iterator cur = pkg->typedefs.begin()
-		       ; cur != pkg->typedefs.end() ; ++cur) {
-
-		  scope->imports[cur->first] = pkg;
-	    }
-
-	    for (map<perm_string,PFunction*>::const_iterator cur = pkg->funcs.begin()
-		       ; cur != pkg->funcs.end() ; ++cur) {
-
-		  scope->imports[cur->first] = pkg;
-	    }
-
-	    for (map<perm_string,PWire*>::const_iterator cur = pkg->wires.begin()
-		       ; cur != pkg->wires.end() ; ++cur) {
-
-		  scope->imports[cur->first] = pkg;
-	    }
-
-            for (set<enum_type_t*>::const_iterator cur = pkg->enum_sets.begin()
-		       ; cur != pkg->enum_sets.end() ; ++ cur) {
-                  scope->enum_sets.insert(*cur);
-            }
       }
 }
 

pform_types.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2007-2008 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2007-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -24,6 +24,11 @@ data_type_t::~data_type_t()
 {
 }
 
+PNamedItem::SymbolType data_type_t::symbol_type() const
+{
+      return TYPE;
+}
+
 string_type_t::~string_type_t()
 {
 }
@@ -44,3 +49,13 @@ ivl_variable_type_t vector_type_t::figure_packed_base_type(void) const
 }
 
 atom2_type_t size_type (32, true);
+
+PNamedItem::SymbolType enum_type_t::symbol_type() const
+{
+      return ENUM;
+}
+
+PNamedItem::SymbolType class_type_t::symbol_type() const
+{
+      return CLASS;
+}

pform_types.h

@@ -1,7 +1,7 @@
 #ifndef IVL_pform_types_H
 #define IVL_pform_types_H
 /*
- * Copyright (c) 2007-2018 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2007-2019 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -21,7 +21,7 @@
 
 // This for the perm_string type.
 # include  "StringHeap.h"
-# include  "LineInfo.h"
+# include  "PNamedItem.h"
 # include  "verinum.h"
 # include  "named.h"
 # include  "netstruct.h"
@@ -137,7 +137,7 @@ struct pform_tf_port_t {
  * "data_type" rule in the parse rule. We make the type virtual so
  * that dynamic types will work.
  */
-class data_type_t : public LineInfo {
+class data_type_t : public PNamedItem {
     public:
       inline explicit data_type_t() { }
       virtual ~data_type_t() = 0;
@@ -149,6 +149,8 @@ class data_type_t : public LineInfo {
 
       ivl_type_s* elaborate_type(Design*des, NetScope*scope);
 
+      virtual SymbolType symbol_type() const;
+
     private:
 	// Elaborate the type to an ivl_type_s type.
       virtual ivl_type_s* elaborate_type_raw(Design*des, NetScope*scope) const;
@@ -171,6 +173,8 @@ struct enum_type_t : public data_type_t {
 	// Return the elaborated version of the type.
       virtual ivl_type_s*elaborate_type_raw(Design*des, NetScope*scope) const;
 
+      SymbolType symbol_type() const;
+
       ivl_variable_type_t base_type;
       bool signed_flag;
       bool integer_flag; // True if "integer" was used
@@ -335,6 +339,8 @@ struct class_type_t : public data_type_t {
 	// type. The elaborate_type_raw() method uses this pointer,
 	// and it is used in some other situations as well.
       netclass_t* save_elaborated_type;
+
+      virtual SymbolType symbol_type() const;
 };
 
 /*

symbol_search.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003-2017 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2003-2019 Stephen Williams (steve@icarus.com)
  * Copyright CERN 2012 / Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
@@ -132,6 +132,11 @@ static bool symbol_search(const LineInfo*li, Design*des, NetScope*scope,
 		  return true;
 	    }
 
+	    if (NetScope*import_scope = scope->find_import(des, path_tail.name)) {
+		  scope = import_scope;
+		  continue;
+	    }
+
 	    if (recurse_flag) {
 		  bool flag = false;
 		  hname_t path_item = eval_path_component(des, start_scope, path_tail, flag);