From d815a147187c0237a81e84e39035f6275b3fee42 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?R=C3=A9my=20Oudompheng?= <oudomphe@phare.normalesup.org>
Date: Mon, 25 Mar 2013 22:09:55 +0100
Subject: [PATCH] cmd/5l, cmd/6l, cmd/8l: fix segfault on reading LOCALS for a
 duplicate definition.

Fixes #5105.

R=golang-dev, dave, daniel.morsing, rsc
CC=golang-dev
https://golang.org/cl/7965043
---
 src/cmd/5l/obj.c                  |  4 ++++
 src/cmd/6l/obj.c                  |  4 ++++
 src/cmd/8l/obj.c                  |  4 ++++
 test/fixedbugs/issue5105.dir/a.go |  7 +++++++
 test/fixedbugs/issue5105.dir/b.go | 15 +++++++++++++++
 test/fixedbugs/issue5105.go       | 10 ++++++++++
 6 files changed, 44 insertions(+)
 create mode 100644 test/fixedbugs/issue5105.dir/a.go
 create mode 100644 test/fixedbugs/issue5105.dir/b.go
 create mode 100644 test/fixedbugs/issue5105.go

diff --git a/src/cmd/5l/obj.c b/src/cmd/5l/obj.c
index d38da204a37..f5128c6780f 100644
--- a/src/cmd/5l/obj.c
+++ b/src/cmd/5l/obj.c
@@ -608,11 +608,15 @@ loop:
 		break;
 
 	case ALOCALS:
+		if(skip)
+			goto casedef;
 		cursym->locals = p->to.offset;
 		pc++;
 		break;
 
 	case ATYPE:
+		if(skip)
+			goto casedef;
 		pc++;
 		goto loop;
 
diff --git a/src/cmd/6l/obj.c b/src/cmd/6l/obj.c
index 3775df9de5c..ab8b22e231b 100644
--- a/src/cmd/6l/obj.c
+++ b/src/cmd/6l/obj.c
@@ -597,11 +597,15 @@ loop:
 		goto loop;
 
 	case ALOCALS:
+		if(skip)
+			goto casdef;
 		cursym->locals = p->to.offset;
 		pc++;
 		goto loop;
 	
 	case ATYPE:
+		if(skip)
+			goto casdef;
 		pc++;
 		goto loop;
 
diff --git a/src/cmd/8l/obj.c b/src/cmd/8l/obj.c
index 306e288a357..fda96d09caa 100644
--- a/src/cmd/8l/obj.c
+++ b/src/cmd/8l/obj.c
@@ -607,11 +607,15 @@ loop:
 		goto loop;
 
 	case ALOCALS:
+		if(skip)
+			goto casdef;
 		cursym->locals = p->to.offset;
 		pc++;
 		goto loop;
 
 	case ATYPE:
+		if(skip)
+			goto casdef;
 		pc++;
 		goto loop;
 
diff --git a/test/fixedbugs/issue5105.dir/a.go b/test/fixedbugs/issue5105.dir/a.go
new file mode 100644
index 00000000000..f20abb98bfa
--- /dev/null
+++ b/test/fixedbugs/issue5105.dir/a.go
@@ -0,0 +1,7 @@
+// Copyright 2013 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 a
+
+var A = [2]string{"hello", "world"}
diff --git a/test/fixedbugs/issue5105.dir/b.go b/test/fixedbugs/issue5105.dir/b.go
new file mode 100644
index 00000000000..b12e739e33a
--- /dev/null
+++ b/test/fixedbugs/issue5105.dir/b.go
@@ -0,0 +1,15 @@
+// Copyright 2013 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
+
+import "./a"
+
+var B = [2]string{"world", "hello"}
+
+func main() {
+	if a.A[0] != B[1] {
+		panic("bad hello")
+	}
+}
diff --git a/test/fixedbugs/issue5105.go b/test/fixedbugs/issue5105.go
new file mode 100644
index 00000000000..e3e5e5caa46
--- /dev/null
+++ b/test/fixedbugs/issue5105.go
@@ -0,0 +1,10 @@
+// rundir
+
+// Copyright 2013 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.
+
+// Issue 5105: linker segfaults on duplicate definition
+// of a type..hash.* function.
+
+package ignored