gc: remove func, map compare
R=ken, ken
CC=golang-dev
https://golang.org/cl/5373079
diff --git a/src/cmd/gc/typecheck.c b/src/cmd/gc/typecheck.c
index 34c241b..aaf836f 100644
--- a/src/cmd/gc/typecheck.c
+++ b/src/cmd/gc/typecheck.c
@@ -445,8 +445,8 @@
yyerror("invalid operation: %N (operator %O not defined on %s)", n, op, typekind(et));
goto error;
}
- // okfor allows any array == array;
- // restrict to slice == nil and nil == slice.
+ // okfor allows any array == array, map == map, func == func.
+ // restrict to slice/map/func == nil and nil == slice/map/func.
if(l->type->etype == TARRAY && !isslice(l->type))
goto notokfor;
if(r->type->etype == TARRAY && !isslice(r->type))
@@ -455,6 +455,15 @@
yyerror("invalid operation: %N (slice can only be compared to nil)", n);
goto error;
}
+ if(l->type->etype == TMAP && !isnil(l) && !isnil(r)) {
+ yyerror("invalid operation: %N (map can only be compared to nil)", n);
+ goto error;
+ }
+ if(l->type->etype == TFUNC && !isnil(l) && !isnil(r)) {
+ yyerror("invalid operation: %N (func can only be compared to nil)", n);
+ goto error;
+ }
+
t = l->type;
if(iscmp[n->op]) {
evconst(n);
