You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
43 lines
1.9 KiB
43 lines
1.9 KiB
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 glibc-2.17-c758a686/sysdeps/generic/symbol-hacks.h glibc-2.17-c758a686/sysdeps/generic/symbol-hacks.h |
|
index bc7b4c4..9eaf014 100644 |
|
--- glibc-2.17-c758a686/sysdeps/generic/symbol-hacks.h |
|
+++ glibc-2.17-c758a686/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 glibc-2.17-c758a686/sysdeps/wordsize-32/symbol-hacks.h glibc-2.17-c758a686/sysdeps/wordsize-32/symbol-hacks.h |
|
index 52a14fc..ad5b231 100644 |
|
--- glibc-2.17-c758a686/sysdeps/wordsize-32/symbol-hacks.h |
|
+++ glibc-2.17-c758a686/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
|
|
|