diff --git a/src/cmd/compile/internal/gc/range.go b/src/cmd/compile/internal/gc/range.go
index 91f0cd363e..d8e504dd14 100644
--- a/src/cmd/compile/internal/gc/range.go
+++ b/src/cmd/compile/internal/gc/range.go
@@ -425,8 +425,7 @@ func walkrange(n *Node) *Node {
 
 	if ifGuard != nil {
 		ifGuard.Ninit.Append(init...)
-		typecheckslice(ifGuard.Left.Ninit.Slice(), Etop)
-		ifGuard.Left = typecheck(ifGuard.Left, Erv)
+		ifGuard = typecheck(ifGuard, Etop)
 	} else {
 		n.Ninit.Append(init...)
 	}