diff --git a/src/cmd/gc/typecheck.c b/src/cmd/gc/typecheck.c
index 072b577a56..90db76960d 100644
--- a/src/cmd/gc/typecheck.c
+++ b/src/cmd/gc/typecheck.c
@@ -2198,6 +2198,7 @@ typecheckcomplit(Node **np)
 		n->typecheck = 1;
 		n->type = n->left->type;
 		n->left->type = t;
+		n->left->typecheck = 1;
 	}
 
 	*np = n;
diff --git a/test/fixedbugs/bug380.go b/test/fixedbugs/bug380.go
new file mode 100644
index 0000000000..75b58064f5
--- /dev/null
+++ b/test/fixedbugs/bug380.go
@@ -0,0 +1,11 @@
+// $G $D/$F.go
+
+// Copyright 2011 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Used to cause a typechecking loop error.
+
+package pkg
+type T map[int]string
+var q = &T{}