diff --git a/src/os/fifo_test.go b/src/os/fifo_test.go
index df4b2ee757..e0386a2d28 100644
--- a/src/os/fifo_test.go
+++ b/src/os/fifo_test.go
@@ -190,6 +190,7 @@ func TestNewFileNonBlocking(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
+	defer f.Close()
 	if !nonblock {
 		t.Error("pipe blocking after NewFile")
 	}