From e8c738ce09f392714aaf0f19cd05a9369740b9d2 Mon Sep 17 00:00:00 2001
From: ian <ian@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Tue, 1 Nov 2011 05:20:40 +0000
Subject: [PATCH] runtime: Don't ask mmap for wrapping memory.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@180732 138bc75d-0d04-0410-961f-82ee72b054a4
---
 libgo/runtime/malloc.goc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libgo/runtime/malloc.goc b/libgo/runtime/malloc.goc
index f8d4327d690..66f5bda66c0 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");
-- 
2.11.0