From: Ian Lance Taylor <ian@gcc.gnu.org>
Date: Tue, 1 Nov 2011 05:20:40 +0000 (+0000)
Subject: runtime: Don't ask mmap for wrapping memory.
X-Git-Tag: releases/gcc-4.7.0~2664
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=787f74b48730d896dba2d15c06a8c792d9d1af15;p=thirdparty%2Fgcc.git

runtime: Don't ask mmap for wrapping memory.

From-SVN: r180732
---

diff --git a/libgo/runtime/malloc.goc b/libgo/runtime/malloc.goc
index f8d4327d6906..66f5bda66c0b 100644
--- a/libgo/runtime/malloc.goc
+++ b/libgo/runtime/malloc.goc
@@ -358,6 +358,8 @@ runtime_mallocinit(void)
 		// away from the running binary image and then round up
 		// to a MB boundary.
 		want = (byte*)(((uintptr)end + (1<<18) + (1<<20) - 1)&~((1<<20)-1));
+		if(0xffffffff - (uintptr)want <= bitmap_size + arena_size)
+		  want = 0;
 		p = runtime_SysReserve(want, bitmap_size + arena_size);
 		if(p == nil)
 			runtime_throw("runtime: cannot reserve arena virtual address space");