From 7dfe8a35215a019f552f117d907eca294225c121 Mon Sep 17 00:00:00 2001
From: Adhemerval Zanella <azanella@linux.vnet.ibm.com>
Date: Wed, 12 Jun 2013 10:21:22 -0500
Subject: [PATCH 35/42] Fix unsafe compiler optimization

GCC 4.8 enables -ftree-loop-distribute-patterns at -O3 by default and
this optimization may transform loops into memset/memmove calls. Without
proper handling this may generate unexpected PLT calls on GLIBC.
This patch fixes by create memset/memmove alias to internal GLIBC
__GI_memset/__GI_memmove symbols.
(cherry picked from commit 6a97b62a5b4f18aea849d6f4d8de58d1469d2521)
---
 sysdeps/generic/symbol-hacks.h     | 7 ++++++-
 sysdeps/wordsize-32/symbol-hacks.h | 2 ++
 3 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/sysdeps/generic/symbol-hacks.h b/sysdeps/generic/symbol-hacks.h
index bc7b4c4..9eaf014 100644
--- a/sysdeps/generic/symbol-hacks.h
+++ b/sysdeps/generic/symbol-hacks.h
@@ -1 +1,6 @@
-/* Fortunately nothing to do.  */
+/* Some compiler optimizations may transform loops into memset/memmove
+   calls and without proper declaration it may generate PLT calls.  */
+#if !defined __ASSEMBLER__ && !defined NOT_IN_libc && defined SHARED
+asm ("memmove = __GI_memmove");
+asm ("memset = __GI_memset");
+#endif
diff --git a/sysdeps/wordsize-32/symbol-hacks.h b/sysdeps/wordsize-32/symbol-hacks.h
index 52a14fc..ad5b231 100644
--- a/sysdeps/wordsize-32/symbol-hacks.h
+++ b/sysdeps/wordsize-32/symbol-hacks.h
@@ -16,6 +16,8 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
+#include_next "symbol-hacks.h"
+
 /* A very dirty trick: gcc emits references to __divdi3, __udivdi3,
    __moddi3, and __umoddi3.  These functions are exported and
    therefore we get PLTs.  Unnecessarily so.  Changing gcc is a big
-- 
1.7.11.7