diff options
Diffstat (limited to '')
-rw-r--r-- | patches/source/glibc/glibc-2.17_gcc48-unsafe-optim.diff | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/patches/source/glibc/glibc-2.17_gcc48-unsafe-optim.diff b/patches/source/glibc/glibc-2.17_gcc48-unsafe-optim.diff new file mode 100644 index 000000000..4de9fe583 --- /dev/null +++ b/patches/source/glibc/glibc-2.17_gcc48-unsafe-optim.diff @@ -0,0 +1,49 @@ +From ea723210a76778c7e86b8df21cb284fc2665ee4f Mon Sep 17 00:00:00 2001 +From: mancha <mancha1 AT zoho DOT com> +Date: Wed, 22 Oct 2014 +Subject: 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 creating memset/memmove aliases to internal GLIBC +__GI_memset/__GI_memmove symbols. + +This fix for use on glibc 2.17 is based on the following upstream +commits: + +https://sourceware.org/git/?p=glibc.git;h=6a97b62a5b4f +https://sourceware.org/git/?p=glibc.git;h=4959e284ca9c + +--- + sysdeps/generic/symbol-hacks.h | 7 ++++++- + sysdeps/wordsize-32/symbol-hacks.h | 2 ++ + sysdeps/x86_64/x32/symbol-hacks.h | 2 +- + 3 files changed, 9 insertions(+), 2 deletions(-) + +--- 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 +--- 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 +--- a/sysdeps/x86_64/x32/symbol-hacks.h ++++ b/sysdeps/x86_64/x32/symbol-hacks.h +@@ -1 +1 @@ +-/* Fortunately nothing to do. */ ++#include <sysdeps/generic/symbol-hacks.h> |