require type assertions when narrowing.
R=ken
OCL=24350
CL=24914
diff --git a/src/cmd/gc/go.h b/src/cmd/gc/go.h
index 436ddd9..7ec215b 100644
--- a/src/cmd/gc/go.h
+++ b/src/cmd/gc/go.h
@@ -827,9 +827,9 @@
Node* chanop(Node*, int);
Node* arrayop(Node*, int);
Node* ifaceop(Type*, Node*, int);
-int ifaceas(Type*, Type*);
-int ifaceas1(Type*, Type*);
-void ifacecheck(Type*, Type*, int);
+int ifaceas(Type*, Type*, int);
+int ifaceas1(Type*, Type*, int);
+void ifacecheck(Type*, Type*, int, int);
void runifacechecks(void);
Node* convas(Node*);
void arrayconv(Type*, Node*);