diff --git a/go/gcimporter15/setname15.go b/go/gcimporter15/setname15.go
index 3d056a88..8f78f540 100644
--- a/go/gcimporter15/setname15.go
+++ b/go/gcimporter15/setname15.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !go1.6
+// +build go1.5,!go1.6
 
 package gcimporter