From b260999d4cfd261ce077b1093c61eea7bd6faf57 Mon Sep 17 00:00:00 2001
From: Shenghou Ma <minux.ma@gmail.com>
Date: Wed, 13 Jun 2012 16:24:15 -0400
Subject: [PATCH] [release-branch.go1] cmd/cc: fix uint right shift in constant
 evaluation
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

««« backport aa2d2fa1e5a9
cmd/cc: fix uint right shift in constant evaluation
        Fixes #3664.

R=golang-dev, bradfitz, rsc
CC=golang-dev
https://golang.org/cl/6249048

»»»
---
 src/cmd/cc/scon.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/cmd/cc/scon.c b/src/cmd/cc/scon.c
index 193331f774d..f6031a5be7e 100644
--- a/src/cmd/cc/scon.c
+++ b/src/cmd/cc/scon.c
@@ -175,7 +175,10 @@ evconst(Node *n)
 		break;
 
 	case OLSHR:
-		v = (uvlong)l->vconst >> r->vconst;
+		if(l->type->width != sizeof(uvlong))
+			v = ((uvlong)l->vconst & 0xffffffffULL) >> r->vconst;
+		else
+			v = (uvlong)l->vconst >> r->vconst;
 		break;
 
 	case OASHR: