This hook can be used to perform additional compatibility checks
between shared libraries by inspecting custom program header
information.
* elf/dl-machine-reject-phdr.h: New file.
* elf/dl-load.c: #include that.
(open_verify): Call elf_machine_reject_phdr_p and ignore the file
if that returned true.
I noticed that install.texi was out of date with regard to the actual
autoconf version requirement for regenerating configure scripts. This
patch updates the documentation.
* manual/install.texi (Tools for Compilation): Update autoconf
version requirements.
* INSTALL: Regenerated.
Continuing the removal of unused __libc_* function names, this patch
removes the __libc_pselect alias.
Tested for x86_64 that installed stripped shared libraries are
unchanged by this patch.
* misc/pselect.c [!__pselect] (__libc_pselect): Remove alias.
* sysdeps/unix/sysv/linux/pselect.c [__NR_pselect6]
(__libc_pselect): Likewise.
Concluding the move of syscall definitions to syscalls.list, where the
removal of support for old kernel versions has made this possible,
this patch removes C definitions of pread, pread64, pwrite and
pwrite64 for powerpc64. As far as I can tell, the existing
syscalls.list definitions in
sysdeps/unix/sysv/linux/wordsize-64/syscalls.list should suffice to
produce results equivalent to what these C files do.
[BZ #14138]
* sysdeps/unix/sysv/linux/powerpc/powerpc64/pread.c: Remove file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/pread64.c: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/pwrite.c: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/pwrite64.c: Likewise.
Continuing the removal of __libc_* function names that are no longer
used anywhere, this patch removes the __libc_readv and __libc_writev
names.
Tested for x86_64 that stripped installed shared libraries are
unchanged by the patch.
* include/sys/uio.h (__libc_readv): Remove declaration.
(__libc_writev): Likewise.
* misc/readv.c (__libc_readv): Rename to __readv.
(__readv): Do not define as alias.
(readv): Define as alias of __readv.
* misc/writev.c (__libc_writev): Rename to __writev.
(__writev): Do not define as alias.
(writev): Define as alias of __writev.
* sysdeps/posix/readv.c (__libc_readv): Rename to __readv.
(__readv): Do not define as alias.
(readv): Define unconditionally as alias of __readv.
* sysdeps/posix/writev.c (__libc_writev): Rename to __writev.
(__writev): Do not define as alias.
(writev): Define unconditionally as alias of __writev.
* sysdeps/unix/syscalls.list (readv): Do not define __libc_readv
name.
(writev): Do not define __libc_writev name.
glibc has lots of __libc_* function names that no longer serve any
purpose (are not used for any calls or exported at a public symbol
version). This patch removes __libc_creat. It has the effect of
creat becoming a strong symbol instead of a weak symbol in various
cases, but that's fine; in shared libraries it doesn't matter at all,
while for static linking the only other symbol sometimes defined in
the same object is creat64, and whenever creat64 is a reserved name so
is creat.
Other such cases of unnecessary __libc_* symbols are expected to be
dealt with in separate patches over time.
Tested for x86_64 (testsuite, and that the disassembly of installed
shared libraries is unchanged by the patch).
* include/fcntl.h (__libc_creat): Remove declaration.
* io/creat.c (__libc_creat): Rename to creat.
(creat): Do not define as alias.
* sysdeps/unix/sysv/linux/alpha/creat.c (creat64): Define as alias
of creat instead of __libc_creat.
* sysdeps/unix/sysv/linux/generic/creat.c (__libc_creat): Rename
to creat.
(creat): Do not define as alias.
[__WORDSIZE == 64] (creat64): Define as alias of creat instead of
__libc_creat.
* sysdeps/unix/sysv/linux/syscalls.list (creat): Do not define
__libc_creat name.
* sysdeps/unix/sysv/linux/wordsize-64/syscalls.list (creat):
Likewise.
Add Linux-specific comments about the atomicity of write() and
the POSIX requirements.
2014-10-29 Carlos O'Donell <carlos@redhat.com>
* manual/llio.texi: Add comments discussing why write() may be
considered MT-unsafe on Linux.
During a refactoring pass several repeated blocks of code in dl-load.c
were turned into a call to a local function named local_strdup. There
is no need for local_strdup, and the routines should instead call
__strdup. This change does just that. We call the internal symbol
__strdup because calling strdup is unsafe. The user might be
using a standard that doesn't include strdup and may have defined this
symbol in their application. During a static link we might reference
the user defined symbol and crash if it doesn't implement a standards
conforming strdup. The resulting code is simpler to understand, and
makes it easier to debug.
No regressions on x86_64.
2014-10-28 Carlos O'Donell <carlos@redhat.com>
* dl-load.c (local_strdup): Remove.
(expand_dynamic_string_token): Use __strdup.
(decompose_rpath): Likewise.
(_dl_map_object): Likewise.
Continuing the removal of the obsolete INTDEF / INTUSE mechanism, this
patch replaces its use in unwind-dw2-fde.c with hidden_def and
hidden_proto.
Tested for x86. This patch does result in code generation differences
(for some reason GCC decides to partition __register_frame_info_bases
after the patch).
[BZ #14132]
* sysdeps/generic/unwind-dw2-fde.c
(__register_frame_info_bases_internal): Do not declare.
(__register_frame_info_table_bases_internal): Likewise.
(__deregister_frame_info_bases_internal): Likewise.
(__register_frame_info_bases): Declare and use hidden_proto before
definition. Use hidden_def instead of INTDEF.
(__register_frame_info_table_bases): Likewise.
(__deregister_frame_info_bases): Likewise.
(__register_frame_info): Do not use INTUSE.
(__register_frame): Likewise.
(__register_frame_info_table): Likewise.
(__register_frame_table): Likewise.
(__deregister_frame_info): Likewise.
(__deregister_frame): Likewise.
ARM linux kernels before 3.14.3 may or may not support
futex_atomic_cmpxchg_inatomic depending on the kernel configuration (e.g.
CONFIG_CPU_USE_DOMAINS && CONFIG_SMP configuration was not supported)
Starting with 3.14.3 the linux kernel unconditionally enables support for
ARM, and this re-enables the relevant __ASSUME_* macros.
Tested on ARM both with kernels >= 3.14.3 and older kernels.
* sysdeps/unix/sysv/linux/arm/kernel-features.h
[__LINUX_KERNEL_VERSION >= 0x030E03] (__ASSUME_FUTEX_LOCK_PI): Do
not undefine.
[__LINUX_KERNEL_VERSION >= 0x030E03] (__ASSUME_REQUEUE_PI):
Likewise.
[__LINUX_KERNEL_VERSION >= 0x030E03] (__ASSUME_SET_ROBUST_LIST):
Likewise.
this
will improve performance even on targets which don't have an optimized strlen. It is about twice
as
fast as the original strncat in bench-strncat.
implementation, so this improves performance even on targets which don't have an optimized
strlen and strcpy - it is 25% faster in bench-strcat. On targets which don't provide an
optimized strcat but which do have an optimized strlen and strcpy, performance gain is > 2x.
Continuing the move of syscall definitions to syscalls.list, where the
removal of support for old kernel versions has made this possible,
this patch moves various definitions of chown, lchown and fchown.
In most cases the need for special syscalls.list entries (rather than
existing generic ones) is because these architectures use chown32,
lchown32 and fchown32 as syscall names. Some architectures also have
symbol versioning compatibility for older versions of chown having
been equivalent to lchown.
The aliases specified for s390-32 had the effect of exporting
__chown@@GLIBC_2.1 (but not __chown@GLIBC_2.0) despite it not being
listed in Versions files. (I'm not sure why versioned_symbol but not
compat_symbol were effective like that to create such __chown exports
in the absence of Versions entries.) The natural way to preserve that
versioned export of __chown seems to be to add it in a Versions file,
so I did so. (Maybe actually it should be a compat symbol,
__chown@GLIBC_2.1, unless there's a good reason for that export, but
this patch doesn't change anything there.)
Tested for x86.
[BZ #14138]
* sysdeps/unix/sysv/linux/i386/chown.c: Remove file.
* sysdeps/unix/sysv/linux/i386/fchown.c: Likewise.
* sysdeps/unix/sysv/linux/i386/lchown.c: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/chown.c: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/fchown.c: Remove file.
* sysdeps/unix/sysv/linux/s390/s390-32/lchown.c: Likewise.
* sysdeps/unix/sysv/linux/sh/chown.c: Likewise.
* sysdeps/unix/sysv/linux/sh/fchown.c: Likewise.
* sysdeps/unix/sysv/linux/sh/lchown.c: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/chown.c: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/fchown.c: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/lchown.c: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/Versions (GLIBC_2.1): Add
__chown.
* sysdeps/unix/sysv/linux/i386/syscalls.list (chown): Add syscall.
(lchown): Likewise.
(fchown): Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/syscalls.list (chown):
Likewise.
(lchown): Likewise.
(fchown): Likewise.
* sysdeps/unix/sysv/linux/sh/syscalls.list (chown): Likewise.
(lchown): Likewise.
(fchown): Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/syscalls.list (chown):
Likewise.
(lchown): Likewise.
(fchown): Likewise.
In the Linux kernel version 3.17 the signal numbers were rearranged in
order to make hppa like every other arch. Previously we started
__SIGRTMIN at 37, and that meant several pieces of important software,
including systemd, would fail to build. To support systemd we removed
SIGEMT and SIGLOST, and rearranged the others according to expected
values. This is technically an ABI incompatible change, but because
zero applications use SIGSTKFLT, SIGXCPU, SIGXFSZ and SIGSYS nothing
broke. Nothing uses SIGEMT and SIGLOST, and they were present for
HPUX compatibility which is no longer supported. Thus because nothing
breaks we don't do any compatibility work here.
Upstream kernel commit is 1f25df2eff5b25f52c139d3ff31bc883eee9a0ab.
Signed-off-by: Carlos O'Donell <carlos@systemhalted.org>
Signed-off-by: Helge Deller <deller@gmx.de>
2014-10-23 Carlos O'Donell <carlos@systemhalted.org>
Helge Deller <deller@gmx.de>
[BZ #17508]
* sysdeps/unix/sysv/linux/hppa/bits/signum.h: Remove SIGEMT.
Define SIGSTKFLT as 7. Define SIGSYS as 31. Define SIGXCPU as 12.
Remove SIGLOST. Define SIGXFSZ as 30. Define __SIGRTMIN as 32.
Continuing the removal of the obsolete INTDEF / INTUSE mechanism, this
patch removes the use of INTUSE to rename symbols in
sysdeps/powerpc/powerpc32/libgcc-compat.S. As the names in question
are purely internal to this particular object and not used anywhere
else, it doesn't matter at all whether __*_v_glibc20 or __*_internal
is used, so this patch just removes the macros in question.
Tested for powerpc32 that stripped installed shared libraries are
unchanged by this patch.
[BZ #14132]
* sysdeps/powerpc/powerpc32/libgcc-compat.S (__ashldi3_v_glibc20):
Remove macro definition.
(__ashrdi3_v_glibc20): Likewise.
(__lshrdi3_v_glibc20): Likewise.
(__cmpdi2_v_glibc20): Likewise.
(__ucmpdi2_v_glibc20): Likewise.
[!_SOFT_FLOAT && !__NO_FPRS__] (__fixdfdi_v_glibc20): Likewise.
[!_SOFT_FLOAT && !__NO_FPRS__] (__fixsfdi_v_glibc20): Likewise.
[!_SOFT_FLOAT && !__NO_FPRS__] (__fixunsdfdi_v_glibc20): Likewise.
[!_SOFT_FLOAT && !__NO_FPRS__] (__fixunssfdi_v_glibc20): Likewise.
[!_SOFT_FLOAT && !__NO_FPRS__] (__floatdidf_v_glibc20): Likewise.
[!_SOFT_FLOAT && !__NO_FPRS__] (__floatdisf_v_glibc20): Likewise.
This satisfies a symbol reference created with:
.symver __libc_vfork, vfork@GLIBC_2.0
where `__libc_vfork' has not been defined or referenced. In this case
the `vfork@GLIBC_2.0' reference is supposed to be discarded, however a
bug present in GAS since forever causes an undefined symbol table entry
to be created. This in turn triggers a problem in the linker that can
manifest itself by link errors such as:
ld: libpthread.so: invalid string offset 2765592330 >= 5154 for section `.dynstr'
The GAS and linker bugs need to be resolved, but we can avoid them too
by providing a `__libc_vfork' definition just like our other platforms.
[BZ #17485]
* sysdeps/unix/sysv/linux/mips/vfork.S (__libc_vfork): Define.
Continuing the removal of the obsolete INTDEF / INTUSE mechanism, this
patch removes the use of INTDEF for __ldexpf. As far as I can tell,
the resulting alias is completely unused.
Tested for x86_64 that stripped installed shared libraries are
unchanged by this patch.
[BZ #14132]
* math/s_ldexpf.c (__ldexpf): Do not use INTDEF.
Continuing the move of syscall definitions to syscalls.list, where the
removal of support for old kernel versions has made this possible,
this patch moves definitions of readv and writev.
The relevant syscalls.list entries were already in
sysdeps/unix/syscalls.list, but to match the C files they needed to
have the names __libc_readv and __libc_writev added. In fact, I don't
see anything making use of those names - as far as I can tell, these
functions could just be defined as __readv and __writev with aliases
readv and writev. But cleaning up unnecessary aliases for functions
should be a separate matter from cleaning up unnecessary C syscall
wrappers.
Tested for x86_64.
[BZ #14138]
* sysdeps/unix/syscalls.list (readv): Use __libc_readv as strong
name.
(writev): Use __libc_writev as strong name.
* sysdeps/unix/sysv/linux/readv.c: Remove file.
* sysdeps/unix/sysv/linux/writev.c: Likewise.
