|
 |
29e444 |
From 7dfe8a35215a019f552f117d907eca294225c121 Mon Sep 17 00:00:00 2001
|
|
|
29e444 |
From: Adhemerval Zanella <azanella@linux.vnet.ibm.com>
|
|
|
29e444 |
Date: Wed, 12 Jun 2013 10:21:22 -0500
|
|
|
29e444 |
Subject: [PATCH 35/42] Fix unsafe compiler optimization
|
|
|
29e444 |
|
|
|
29e444 |
GCC 4.8 enables -ftree-loop-distribute-patterns at -O3 by default and
|
|
|
29e444 |
this optimization may transform loops into memset/memmove calls. Without
|
|
|
29e444 |
proper handling this may generate unexpected PLT calls on GLIBC.
|
|
|
29e444 |
This patch fixes by create memset/memmove alias to internal GLIBC
|
|
|
29e444 |
__GI_memset/__GI_memmove symbols.
|
|
|
29e444 |
(cherry picked from commit 6a97b62a5b4f18aea849d6f4d8de58d1469d2521)
|
|
|
29e444 |
---
|
|
|
29e444 |
sysdeps/generic/symbol-hacks.h | 7 ++++++-
|
|
|
29e444 |
sysdeps/wordsize-32/symbol-hacks.h | 2 ++
|
|
|
29e444 |
3 files changed, 16 insertions(+), 1 deletion(-)
|
|
|
29e444 |
|
|
|
12745e |
diff --git glibc-2.17-c758a686/sysdeps/generic/symbol-hacks.h glibc-2.17-c758a686/sysdeps/generic/symbol-hacks.h
|
|
|
29e444 |
index bc7b4c4..9eaf014 100644
|
|
|
12745e |
--- glibc-2.17-c758a686/sysdeps/generic/symbol-hacks.h
|
|
|
12745e |
+++ glibc-2.17-c758a686/sysdeps/generic/symbol-hacks.h
|
|
|
29e444 |
@@ -1 +1,6 @@
|
|
|
29e444 |
-/* Fortunately nothing to do. */
|
|
|
29e444 |
+/* Some compiler optimizations may transform loops into memset/memmove
|
|
|
29e444 |
+ calls and without proper declaration it may generate PLT calls. */
|
|
|
29e444 |
+#if !defined __ASSEMBLER__ && !defined NOT_IN_libc && defined SHARED
|
|
|
29e444 |
+asm ("memmove = __GI_memmove");
|
|
|
29e444 |
+asm ("memset = __GI_memset");
|
|
|
29e444 |
+#endif
|
|
|
12745e |
diff --git glibc-2.17-c758a686/sysdeps/wordsize-32/symbol-hacks.h glibc-2.17-c758a686/sysdeps/wordsize-32/symbol-hacks.h
|
|
|
29e444 |
index 52a14fc..ad5b231 100644
|
|
|
12745e |
--- glibc-2.17-c758a686/sysdeps/wordsize-32/symbol-hacks.h
|
|
|
12745e |
+++ glibc-2.17-c758a686/sysdeps/wordsize-32/symbol-hacks.h
|
|
|
29e444 |
@@ -16,6 +16,8 @@
|
|
|
29e444 |
License along with the GNU C Library; if not, see
|
|
|
29e444 |
<http://www.gnu.org/licenses/>. */
|
|
|
29e444 |
|
|
|
29e444 |
+#include_next "symbol-hacks.h"
|
|
|
29e444 |
+
|
|
|
29e444 |
/* A very dirty trick: gcc emits references to __divdi3, __udivdi3,
|
|
|
29e444 |
__moddi3, and __umoddi3. These functions are exported and
|
|
|
29e444 |
therefore we get PLTs. Unnecessarily so. Changing gcc is a big
|
|
|
29e444 |
--
|
|
|
29e444 |
1.7.11.7
|
|
|
29e444 |
|