diff --git a/src/cmd/gc/const.c b/src/cmd/gc/const.c
index 5829904196..8cc4c247d6 100644
--- a/src/cmd/gc/const.c
+++ b/src/cmd/gc/const.c
@@ -335,6 +335,7 @@ evconst(Node *n)
 	case OMAKESLICE:
 	case OMAKECHAN:
 	case ODCLCONST:
+	case OCONVIFACE:
 		return;
 	}