compile/internal/gc: make typecheckok a bool

Change-Id: Ib3960321a4c8164f6b221bfd15977d2f34dbc65b
Reviewed-on: https://go-review.googlesource.com/14175
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/src/cmd/compile/internal/gc/dcl.go b/src/cmd/compile/internal/gc/dcl.go
index 99f29f4..157f525 100644
--- a/src/cmd/compile/internal/gc/dcl.go
+++ b/src/cmd/compile/internal/gc/dcl.go
@@ -182,7 +182,7 @@
 	s := n.Sym
 
 	// kludgy: typecheckok means we're past parsing.  Eg genwrapper may declare out of package names later.
-	if importpkg == nil && typecheckok == 0 && s.Pkg != localpkg {
+	if importpkg == nil && !typecheckok && s.Pkg != localpkg {
 		Yyerror("cannot declare name %v", s)
 	}