From 6948c27c2d01de7257a47308c17f7f907ace1747 Mon Sep 17 00:00:00 2001
From: Cary R <cygcary@yahoo.com>
Date: Tue, 4 Nov 2014 14:55:40 -0800
Subject: [PATCH] Enumerations are compatible if their type definitions match.

---
 elab_scope.cc |  3 ++-
 elaborate.cc  |  4 +++-
 netenum.cc    | 13 ++++++++++---
 netenum.h     |  8 +++++++-
 4 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/elab_scope.cc b/elab_scope.cc
index d352261a6..6e594c241 100644
--- a/elab_scope.cc
+++ b/elab_scope.cc
@@ -180,7 +180,8 @@ static void elaborate_scope_enumeration(Design*des, NetScope*scope,
       netenum_t*use_enum = new netenum_t(enum_type->base_type,
 					 enum_type->signed_flag,
 					 enum_type->integer_flag, msb, lsb,
-					 enum_type->names->size());
+					 enum_type->names->size(),
+					 enum_type);
 
       use_enum->set_line(enum_type->li);
       if (scope)
diff --git a/elaborate.cc b/elaborate.cc
index 17d37c098..95005c140 100644
--- a/elaborate.cc
+++ b/elaborate.cc
@@ -38,6 +38,7 @@
 # include  "PPackage.h"
 # include  "PSpec.h"
 # include  "netlist.h"
+# include  "netenum.h"
 # include  "netvector.h"
 # include  "netdarray.h"
 # include  "netparray.h"
@@ -2668,7 +2669,8 @@ NetProc* PAssign::elaborate(Design*des, NetScope*scope) const
 	    return bl;
       }
 
-      if (lv->enumeration() && (lv->enumeration() != rv->enumeration())) {
+      if (lv->enumeration() &&
+          ! lv->enumeration()->matches(rv->enumeration())) {
 	    cerr << get_fileline() << ": error: "
 		 << "Enumeration type mismatch in assignment." << endl;
 	    des->errors += 1;
diff --git a/netenum.cc b/netenum.cc
index cab73a55c..0ec7ca33d 100644
--- a/netenum.cc
+++ b/netenum.cc
@@ -24,9 +24,11 @@
 using namespace std;
 
 netenum_t::netenum_t(ivl_variable_type_t btype, bool signed_flag,
-		     bool integer_flag, long msb, long lsb, size_t name_count)
-: base_type_(btype), signed_flag_(signed_flag), integer_flag_(integer_flag),
-  msb_(msb), lsb_(lsb), names_(name_count), bits_(name_count)
+		     bool integer_flag, long msb, long lsb, size_t name_count,
+		     enum_type_t*enum_type)
+: base_type_(btype), enum_type_(enum_type), signed_flag_(signed_flag),
+  integer_flag_(integer_flag), msb_(msb), lsb_(lsb),
+  names_(name_count), bits_(name_count)
 {
 }
 
@@ -161,3 +163,8 @@ perm_string netenum_t::bits_at(size_t idx) const
 {
       return bits_[idx];
 }
+
+bool netenum_t::matches(const netenum_t*other) const
+{
+      return enum_type_ == other->enum_type_;
+}
diff --git a/netenum.h b/netenum.h
index 64c2aac6a..8ff8a9063 100644
--- a/netenum.h
+++ b/netenum.h
@@ -29,12 +29,14 @@
 
 class NetScope;
 
+struct enum_type_t;
+
 class netenum_t : public LineInfo, public ivl_type_s {
 
     public:
       explicit netenum_t(ivl_variable_type_t base_type, bool signed_flag,
 			 bool isint_flag, long msb, long lsb,
-			 size_t name_count);
+			 size_t name_count, enum_type_t*enum_type);
       ~netenum_t();
 
       virtual ivl_variable_type_t base_type() const;
@@ -67,8 +69,12 @@ class netenum_t : public LineInfo, public ivl_type_s {
       perm_string name_at(size_t idx) const;
       perm_string bits_at(size_t idx) const;
 
+	// Check if two enumerations have the same definition.
+      bool matches(const netenum_t*other) const;
+
     private:
       ivl_variable_type_t base_type_;
+      enum_type_t*enum_type_;
       bool signed_flag_;
       bool integer_flag_;
       long msb_, lsb_;