On 23/04/15 17:36, Jakub Jelinek wrote:
Hi!
This patch undoes the PR65780 performance regressions on a few targets
I have tested to work fine.
This PR was about an access to uninitialized COMMON symbol defined in
executable (or PIE) where there is a normal symbol definition in a shared
library. The PR65780 fix that got committed stopped treating
such COMMONs as binding local on all architectures, except for i?86 (for
normal execs only) and x86_64 (for normal execs and PIEs, but the latter
only with recent linker). As s390/arm/aarch64 seems to work fine
(generate a COPY relocation and thus define symbol locally) in non-PIE
executables, this patch changes those to a function that has been added for
that behavior. E.g. powerpc64{,le} on the other side isn't able to link
that case neither in normal execs nor PIEs.
Bootstrapped/regtested on
{x86_64,i686,armv7hl,aarch64,s390{,x},powerpc64{,le}}-linux, ok for trunk
(and perhaps after a while for 5.2)?
The ARM bits are OK.
regards
Ramana
2015-04-23 Jakub Jelinek <[email protected]>
PR target/65780
* config/s390/linux.h (TARGET_BINDS_LOCAL_P): Define to
default_binds_local_p_2.
* config/arm/linux-elf.h (TARGET_BINDS_LOCAL_P): Likewise.
* config/aarch64/aarch64-linux.h (TARGET_BINDS_LOCAL_P): Likewise.
--- gcc/config/s390/linux.h.jj 2015-01-05 13:07:16.000000000 +0100
+++ gcc/config/s390/linux.h 2015-04-22 17:39:38.880273650 +0200
@@ -90,4 +90,10 @@ along with GCC; see the file COPYING3.
#undef TARGET_LIBC_HAS_FUNCTION
#define TARGET_LIBC_HAS_FUNCTION gnu_libc_has_function
+/* Uninitialized common symbols in non-PIE executables, even with
+ strong definitions in dependent shared libraries, will resolve
+ to COPY relocated symbol in the executable. See PR65780. */
+#undef TARGET_BINDS_LOCAL_P
+#define TARGET_BINDS_LOCAL_P default_binds_local_p_2
+
#endif
--- gcc/config/arm/linux-elf.h.jj 2015-01-05 13:07:16.000000000 +0100
+++ gcc/config/arm/linux-elf.h 2015-04-22 17:42:35.979420149 +0200
@@ -118,3 +118,9 @@
/* Add .note.GNU-stack. */
#undef NEED_INDICATE_EXEC_STACK
#define NEED_INDICATE_EXEC_STACK 1
+
+/* Uninitialized common symbols in non-PIE executables, even with
+ strong definitions in dependent shared libraries, will resolve
+ to COPY relocated symbol in the executable. See PR65780. */
+#undef TARGET_BINDS_LOCAL_P
+#define TARGET_BINDS_LOCAL_P default_binds_local_p_2
--- gcc/config/aarch64/aarch64-linux.h.jj 2015-01-05 13:07:17.000000000
+0100
+++ gcc/config/aarch64/aarch64-linux.h 2015-04-22 17:40:46.395185820 +0200
@@ -69,4 +69,10 @@
#define TARGET_ASM_FILE_END file_end_indicate_exec_stack
+/* Uninitialized common symbols in non-PIE executables, even with
+ strong definitions in dependent shared libraries, will resolve
+ to COPY relocated symbol in the executable. See PR65780. */
+#undef TARGET_BINDS_LOCAL_P
+#define TARGET_BINDS_LOCAL_P default_binds_local_p_2
+
#endif /* GCC_AARCH64_LINUX_H */
Jakub
