cmd/gc: when expanding append inline, preserve arguments
Fixes #3369.
R=golang-dev, gri, lvd, r
CC=golang-dev
https://golang.org/cl/5876044
diff --git a/test/fixedbugs/bug428.go b/test/fixedbugs/bug428.go
new file mode 100644
index 0000000..298c455
--- /dev/null
+++ b/test/fixedbugs/bug428.go
@@ -0,0 +1,19 @@
+// run
+
+// Copyright 2012 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.
+
+// Test that when the compiler expands append inline it does not
+// overwrite a value before it needs it (issue 3369).
+
+package main
+
+func main() {
+ s := make([]byte, 5, 6)
+ copy(s, "12346")
+ s = append(s[:len(s)-1], '5', s[len(s)-1])
+ if string(s) != "123456" {
+ panic(s)
+ }
+}
