test: add test case for which gccgo generated incorrect GC info

Change-Id: I5e33db9e63f70706882b85ab124a48509797b05a
Reviewed-on: https://go-review.googlesource.com/33790
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

diff --git a/test/fixedbugs/bug500.go b/test/fixedbugs/bug500.go
new file mode 100644 (file)
index 0000000..2dd5df1
--- /dev/null
+++ b/test/fixedbugs/bug500.go
@@ -0,0 +1,41 @@
+// run
+
+// Copyright 2016 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.
+
+// Gccgo generated incorrect GC info when a global variable was
+// initialized to a slice of a value containing pointers.  The initial
+// backing array for the slice was allocated in the .data section,
+// which is fine, but the backing array was not registered as a GC
+// root.
+
+package main
+
+import (
+       "runtime"
+)
+
+type s struct {
+       str string
+}
+
+var a = []struct {
+       str string
+}{
+       {""},
+}
+
+var b = "b"
+var c = "c"
+
+func init() {
+       a[0].str = b + c
+}
+
+func main() {
+       runtime.GC()
+       if a[0].str != b + c {
+               panic(a[0].str)
+       }
+}