From 55ec7e3af4823fc378f78e35b795af1bafcd3542 Mon Sep 17 00:00:00 2001
From: ebotcazou <ebotcazou@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Tue, 3 May 2011 07:20:30 +0000
Subject: [PATCH] 	PR target/48723
 	* config/i386/i386.c (ix86_expand_prologue): Do not probe the stack
 	for -fstack-check if the size to allocate is negative.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gcc-4_6-branch@173289 138bc75d-0d04-0410-961f-82ee72b054a4

index 6e4bb3b..f3a8a0c 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -10566,8 +10566,8 @@ ix86_expand_prologue (void)
     }
 
   /* The stack has already been decremented by the instruction calling us
-     so we need to probe unconditionally to preserve the protection area.  */
-  if (flag_stack_check == STATIC_BUILTIN_STACK_CHECK)
+     so probe if the size is non-negative to preserve the protection area.  */
+  if (allocate >= 0 && flag_stack_check == STATIC_BUILTIN_STACK_CHECK)
     {
       /* We expect the registers to be saved when probes are used.  */
       gcc_assert (int_registers_saved);
-- 
1.7.0.4