With --bbox-unsup, suppress desassign and mixed edges, bug1120.

Changes

@@ -5,6 +5,8 @@ The contributors that suggested a given feature are shown in []. Thanks!
 
 * Verilator 3.891 devel
 
+****  With --bbox-unsup, suppress desassign and mixed edges, bug1120. [Galen Seitz]
+
 ****  Fix internal error on double-for loop unrolling, bug1044. [Jan Egil Ruud]
 
 ****  Fix internal error on unique casez with --assert, bug1117. [Enzo Chi]

bin/verilator

@@ -444,9 +444,10 @@ calls.
 
 =item --bbox-unsup
 
-Black box some unsupported language features, currently UDP tables and the
+Black box some unsupported language features, currently UDP tables, the
-cmos and tran gate primitives.  This may enable linting the rest of the
+cmos and tran gate primitives, deassign statements, and mixed edge errors.
-design even when unsupported constructs are present.
+This may enable linting the rest of the design even when unsupported
+constructs are present.
 
 =item --bin I<filename>
 

src/V3Active.cpp

@@ -329,7 +329,9 @@ private:
 
 	if (!combo && !sequent) combo=true;	// If no list, Verilog 2000: always @ (*)
 	if (combo && sequent) {
-	    nodep->v3error("Unsupported: Mixed edge (pos/negedge) and activity (no edge) sensitive activity list");
+	    if (!v3Global.opt.bboxUnsup()) {
+		nodep->v3error("Unsupported: Mixed edge (pos/negedge) and activity (no edge) sensitive activity list");
+	    }
 	    sequent = false;
 	}
 

src/verilog.l

@@ -247,6 +247,7 @@ vnum	{vnum1}|{vnum2}|{vnum3}|{vnum4}|{vnum5}
   "casex"		{ FL; return yCASEX; }
   "casez"		{ FL; return yCASEZ; }
   "cmos"		{ FL; return yCMOS; }
+  "deassign"		{ FL; return yDEASSIGN; }
   "default"		{ FL; return yDEFAULT; }
   "defparam"		{ FL; return yDEFPARAM; }
   "disable"		{ FL; return yDISABLE; }
@@ -329,7 +330,6 @@ vnum	{vnum1}|{vnum2}|{vnum3}|{vnum4}|{vnum5}
   "$writeh"		{ FL; RETURN_BBOX_SYS_OR_MSG("Unsupported: Use $write with %%x format instead: %s",yytext); }
   "$writeo"		{ FL; RETURN_BBOX_SYS_OR_MSG("Unsupported: Use $write with %%o format instead: %s",yytext); }
   /*     Generic unsupported warnings */
-  "deassign"		{ yyerrorf("Unsupported: Verilog 1995 reserved word not implemented: %s",yytext); }
   "event"		{ yyerrorf("Unsupported: Verilog 1995 reserved word not implemented: %s",yytext); }
   "force"		{ yyerrorf("Unsupported: Verilog 1995 reserved word not implemented: %s",yytext); }
   "fork"		{ yyerrorf("Unsupported: Verilog 1995 reserved word not implemented: %s",yytext); }

src/verilog.y

@@ -320,6 +320,7 @@ class AstSenTree;
 %token<fl>		yCONTEXT	"context"
 %token<fl>		yCONTINUE	"continue"
 %token<fl>		yCOVER		"cover"
+%token<fl>		yDEASSIGN	"deassign"
 %token<fl>		yDEFAULT	"default"
 %token<fl>		yDEFPARAM	"defparam"
 %token<fl>		yDISABLE	"disable"
@@ -2263,7 +2264,8 @@ statement_item<nodep>:		// IEEE: statement_item
 	//			// IEEE: procedural_continuous_assignment
 	|	yASSIGN idClassSel '=' delayE expr ';'	{ $$ = new AstAssign($1,$2,$5); }
 	//UNSUP:			delay_or_event_controlE above
-	//UNSUP	yDEASSIGN variable_lvalue ';'		{ UNSUP }
+	|	yDEASSIGN variable_lvalue ';'		{ if (!v3Global.opt.bboxUnsup()) $1->v3error("Unsupported: Verilog 1995 deassign"); $$ = NULL; }
+
 	//UNSUP	yFORCE expr '=' expr ';'		{ UNSUP }
 	//UNSUP	yRELEASE variable_lvalue ';'		{ UNSUP }
 	//

test_regress/t/t_lint_unsup_deassign.pl

@@ -0,0 +1,18 @@
+#!/usr/bin/perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2003 by Wilson Snyder. This program is free software; you can
+# redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+
+compile (
+    v_flags2 => ["--lint-only --bbox-unsup"],
+    verilator_make_gcc => 0,
+    make_top_shell => 0,
+    make_main => 0,
+    );
+
+ok(1);
+1;

test_regress/t/t_lint_unsup_deassign.v

@@ -0,0 +1,19 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed into the Public Domain, for any use,
+// without warranty, 2016 by Wilson Snyder.
+
+module t
+   (
+   input wire rst
+   );
+
+   integer q;
+   
+   always @(*)
+     if (rst)
+       assign q = 0;
+     else
+       deassign q;
+
+endmodule

test_regress/t/t_lint_unsup_mixed.pl

@@ -0,0 +1,18 @@
+#!/usr/bin/perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2003 by Wilson Snyder. This program is free software; you can
+# redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+
+compile (
+    v_flags2 => ["--lint-only --bbox-unsup"],
+    verilator_make_gcc => 0,
+    make_top_shell => 0,
+    make_main => 0,
+    );
+
+ok(1);
+1;

test_regress/t/t_lint_unsup_mixed.v

@@ -0,0 +1,22 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed into the Public Domain, for any use,
+// without warranty, 2016 by Wilson Snyder.
+
+module t
+   (
+   input wire clk,
+   input wire a
+   );
+
+   integer q;
+   
+   always @ (a or posedge clk)
+     begin
+	if (a)
+          q = 0;
+	else 
+          q = q + 1;
+     end
+
+endmodule