From 4350c15673a49ca1eacee5670b12d72e3272e3f5 Mon Sep 17 00:00:00 2001
From: Mark H Weaver <mhw@netris.org>
Date: Sat, 3 Aug 2013 14:51:07 -0400
Subject: [PATCH] VM: Avoid overflow in ASM_ADD when the result is
 most-positive-fixnum.

* libguile/vm-i-scheme.c (ASM_ADD): Remove the tag from one of the
  operands before adding, to avoid overflow when the result is the most
  positive fixnum.
---
 libguile/vm-i-scheme.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libguile/vm-i-scheme.c b/libguile/vm-i-scheme.c
index d52eec76c..da56860c6 100644
--- a/libguile/vm-i-scheme.c
+++ b/libguile/vm-i-scheme.c
@@ -248,8 +248,8 @@ VM_DEFINE_FUNCTION (149, ge, "ge?", 2)
       asm volatile goto ("mov %1, %%rcx; "				\
 			 "test %[tag], %%cl; je %l[slow_add]; "		\
 			 "test %[tag], %0;   je %l[slow_add]; "		\
-			 "add %0, %%rcx;     jo %l[slow_add]; "		\
 			 "sub %[tag], %%rcx; "				\
+			 "add %0, %%rcx;     jo %l[slow_add]; "		\
 			 "mov %%rcx, (%[vsp])\n"			\
 			 : /* no outputs */				\
 			 : "r" (x), "r" (y),				\