Fix error on referencing variable in parent, bug1099.

Changes

@@ -9,6 +9,8 @@ The contributors that suggested a given feature are shown in []. Thanks!
 
 ****  Fix error on bad interface name, bug1097. [Todd Strader]
 
+****  Fix error on referencing variable in parent, bug1099. [Ian Thompson]
+
 ****  Fix type parameters with low optimization, bug1101. [Stefan Wallentowitz]
 
 

src/V3LinkDot.cpp

@@ -490,7 +490,7 @@ public:
 		}
 	    }
 	    UINFO(8,"         id "<<ident<<" alt "<<altIdent<<" left "<<leftname<<" at se"<<lookupSymp<<endl);
-	    // Spec says; Look at exiting module (cellnames then modname),
+	    // Spec says; Look at existing module (cellnames then modname),
 	    // then look up (inst name or modname)
 	    if (firstId) {
 		// Check this module - subcellnames
@@ -504,18 +504,26 @@ public:
 			 || (inlinep && inlinep->origModName() == ident)) {}
 		// Move up and check cellname + modname
 		else {
+		    bool crossedCell = false;  // Crossed a cell boundary
 		    while (lookupSymp) {
 			lookupSymp = lookupSymp->parentp();
 			cellp   = lookupSymp ? lookupSymp->nodep()->castCell() : NULL; // Replicated above
 			inlinep = lookupSymp ? lookupSymp->nodep()->castCellInline() : NULL; // Replicated above
 			if (lookupSymp) {
 			    UINFO(9,"\t\tUp to "<<lookupSymp<<endl);
+			    if (cellp || inlinep) {
+				crossedCell = true;
+			    }
 			    if ((cellp && cellp->modp()->origName() == ident)
 				|| (inlinep && inlinep->origModName() == ident)) {
 				break;
 			    }
 			    else if (VSymEnt* findSymp = findWithAltFallback(lookupSymp, ident, altIdent)) {
 				lookupSymp = findSymp;
+				if (crossedCell && lookupSymp->nodep()->castVar()) {
+				    UINFO(9,"\t\tNot found but matches var name in parent "<<lookupSymp<<endl);
+				    return NULL;  // Not found (but happens to be var name in parent)
+				}
 				break;
 			    }
 			} else break;

test_regress/t/t_param_up_bad.pl

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

test_regress/t/t_param_up_bad.v

@@ -0,0 +1,31 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed into the Public Domain, for any use,
+// without warranty, 2016 by Ian Thompson.
+
+//bug1099
+
+typedef struct packed {
+   logic       foo;
+} some_struct_t;
+
+module child ();
+   logic a_bad;
+   // bar is in the parent module, but illegal to reference without module name
+   assign a_bad = bar.foo;
+endmodule
+
+module parent
+  #(
+    parameter PARAM = 0
+    )
+   (
+    );
+   some_struct_t bar;
+   child c ();
+endmodule
+
+module t ();
+   // The parameter must be anything other than the default
+   parent #( 1 ) p ();
+endmodule