out of bounds bug

R=r
DELTA=9  (9 added, 0 deleted, 0 changed)
OCL=15223
CL=15223

test/bugs/bug102.go

+// $G $D/$F.go && $L $F.$A && ./$A.out || echo BUG: should not crash
+
+// Copyright 2009 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.
+
+package main
+
+func main() {
+	var b [0]byte;
+	s := string(b);	// out of bounds trap
+}
+