From: Shenghou Ma <minux.ma@gmail.com>
Date: Thu, 17 Apr 2014 03:12:06 +0000 (-0400)
Subject: cmd/gc: fix segfault in isgoconst.
X-Git-Tag: go1.3beta1~30
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=32dffef0980eb810b97f48eb9dfabb33602a0472;p=gostls13.git

cmd/gc: fix segfault in isgoconst.

Variables declared with 'var' have no sym->def.

Fixes #7794.

LGTM=rsc
R=golang-codereviews, bradfitz, rsc
CC=golang-codereviews
https://golang.org/cl/88360043
---

diff --git a/src/cmd/gc/const.c b/src/cmd/gc/const.c
index 28d0725d33..f356c4f59a 100644
--- a/src/cmd/gc/const.c
+++ b/src/cmd/gc/const.c
@@ -1594,7 +1594,7 @@ isgoconst(Node *n)
 
 	case ONAME:
 		l = n->sym->def;
-		if(l->op == OLITERAL && n->val.ctype != CTNIL)
+		if(l && l->op == OLITERAL && n->val.ctype != CTNIL)
 			return 1;
 		break;
 	
diff --git a/test/fixedbugs/issue7794.go b/test/fixedbugs/issue7794.go
new file mode 100644
index 0000000000..1e303bd4f2
--- /dev/null
+++ b/test/fixedbugs/issue7794.go
@@ -0,0 +1,12 @@
+// compile
+
+// Copyright 2014 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 a [10]int
+	const ca = len(a)
+}