From feb1e2bd488cdf636ff3d5b6ff6185efcf68be69 Mon Sep 17 00:00:00 2001
From: Wilson Snyder <wsnyder@wsnyder.org>
Date: Sun, 10 May 2020 11:01:57 -0400
Subject: [PATCH] Commentary

---
 src/verilog.y              | 6 ++++++
 test_regress/t/t_typedef.v | 1 +
 2 files changed, 7 insertions(+)

diff --git a/src/verilog.y b/src/verilog.y
index 06f21b7ec..fd52d94b5 100644
--- a/src/verilog.y
+++ b/src/verilog.y
@@ -1971,6 +1971,8 @@ type_declaration<nodep>:	// ==IEEE: type_declaration
 	|	yTYPEDEF id/*interface*/ '.' idAny/*type*/ idAny/*type*/ ';'	{ $$ = NULL; BBUNSUP($1, "Unsupported: SystemVerilog 2005 typedef in this context"); }
 	//			// Combines into above "data_type id" rule
 	//			// Verilator: Not important what it is in the AST, just need to make sure the yaID__aTYPE gets returned
+	//UNSUP			// Below should be idAny to allow duplicate forward defs; need to expand
+	//			// data_type to exclude IDs, or add id__SEMI rule
 	|	yTYPEDEF id ';'				{ $$ = NULL; $$ = new AstTypedefFwd($<fl>2, *$2); SYMP->reinsert($$); PARSEP->tagNodep($$); }
 	|	yTYPEDEF yENUM idAny ';'		{ $$ = NULL; $$ = new AstTypedefFwd($<fl>3, *$3); SYMP->reinsert($$); PARSEP->tagNodep($$); }
 	|	yTYPEDEF ySTRUCT idAny ';'		{ $$ = NULL; $$ = new AstTypedefFwd($<fl>3, *$3); SYMP->reinsert($$); PARSEP->tagNodep($$); }
@@ -4267,6 +4269,8 @@ gateRangeE<nodep>:
 gateBuf<nodep>:
 		gateFront variable_lvalue ',' gatePinExpr ')'
 			{ $$ = new AstAssignW($<fl>1, $2, $4); DEL($1); }
+	// UNSUP			// IEEE: Multiple output variable_lvalues
+	// UNSUP			// Causes conflict - need to take in variable_lvalue or a gatePinExpr
 	;
 gateBufif0<nodep>:
 		gateFront variable_lvalue ',' gatePinExpr ',' gatePinExpr ')'
@@ -4279,6 +4283,8 @@ gateBufif1<nodep>:
 gateNot<nodep>:
 		gateFront variable_lvalue ',' gatePinExpr ')'
 			{ $$ = new AstAssignW($<fl>1, $2, new AstNot($<fl>1, $4)); DEL($1); }
+	// UNSUP			// IEEE: Multiple output variable_lvalues
+	// UNSUP			// Causes conflict - need to take in variable_lvalue or a gatePinExpr
 	;
 gateNotif0<nodep>:
 		gateFront variable_lvalue ',' gatePinExpr ',' gatePinExpr ')'
diff --git a/test_regress/t/t_typedef.v b/test_regress/t/t_typedef.v
index 78f966825..693f3406e 100644
--- a/test_regress/t/t_typedef.v
+++ b/test_regress/t/t_typedef.v
@@ -8,6 +8,7 @@ program t;
    parameter SIZE = 5;
 
    typedef vec_t;  // Forward
+   //UNSUP typedef vec_t;  // Multi-forward is ok
 
    typedef reg [SIZE-1:0] vec_t ;
    vec_t a; initial a =0;