ldconfig supports `include' directives and use the glob function to
process them. The glob function sort entries according to the LC_COLLATE
category. When using a standard "include /etc/ld.so.conf.d/*.conf" entry
in /etc/ld.so.conf, the order therefore depends on the locale used to
run ldconfig. A few examples of locale specific order that might be
disturbing in that context compared to the C locale:
- The cs_CZ and sk_SK locales sort the digits after the letters.
- The et_EE locale sorts the 'z' between 's' and 't'.
This patch fixes that by setting LC_COLLATE to C in order to process
files in deterministic order, independently of the locale used to launch
ldconfig.
NOTE: This should NOT be backported to older release branches.
Changelog:
[BZ #22505]
* elf/ldconfig.c (main): Call setlocale to force LC_COLLATE to C.
Static PIE extends address space layout randomization to static
executables. It provides additional security hardening benefits at
the cost of some memory and performance.
Dynamic linker, ld.so, is a standalone program which can be loaded at
any address. This patch adds a configure option, --enable-static-pie,
to embed the part of ld.so in static executable to create static position
independent executable (static PIE). A static PIE is similar to static
executable, but can be loaded at any address without help from a dynamic
linker. When --enable-static-pie is used to configure glibc, libc.a is
built as PIE and all static executables, including tests, are built as
static PIE. The resulting libc.a can be used together with GCC 8 or
above to build static PIE with the compiler option, -static-pie. But
GCC 8 isn't required to build glibc with --enable-static-pie. Only GCC
with PIE support is needed. When an older GCC is used to build glibc
with --enable-static-pie, proper input files are passed to linker to
create static executables as static PIE, together with "-z text" to
prevent dynamic relocations in read-only segments, which are not allowed
in static PIE.
The following changes are made for static PIE:
1. Add a new function, _dl_relocate_static_pie, to:
a. Get the run-time load address.
b. Read the dynamic section.
c. Perform dynamic relocations.
Dynamic linker also performs these steps. But static PIE doesn't load
any shared objects.
2. Call _dl_relocate_static_pie at entrance of LIBC_START_MAIN in
libc.a. crt1.o, which is used to create dynamic and non-PIE static
executables, is updated to include a dummy _dl_relocate_static_pie.
rcrt1.o is added to create static PIE, which will link in the real
_dl_relocate_static_pie. grcrt1.o is also added to create static PIE
with -pg. GCC 8 has been updated to support rcrt1.o and grcrt1.o for
static PIE.
Static PIE can work on all architectures which support PIE, provided:
1. Target must support accessing of local functions without dynamic
relocations, which is needed in start.S to call __libc_start_main with
function addresses of __libc_csu_init, __libc_csu_fini and main. All
functions in static PIE are local functions. If PIE start.S can't reach
main () defined in a shared object, the code sequence:
pass address of local_main to __libc_start_main
...
local_main:
tail call to main via PLT
can be used.
2. start.S is updated to check PIC instead SHARED for PIC code path and
avoid dynamic relocation, when PIC is defined and SHARED isn't defined,
to support static PIE.
3. All assembly codes are updated check PIC instead SHARED for PIC code
path to avoid dynamic relocations in read-only sections.
4. All assembly codes are updated check SHARED instead PIC for static
symbol name.
5. elf_machine_load_address in dl-machine.h are updated to support static
PIE.
6. __brk works without TLS nor dynamic relocations in read-only section
so that it can be used by __libc_setup_tls to initializes TLS in static
PIE.
NB: When glibc is built with GCC defaulted to PIE, libc.a is compiled
with -fPIE, regardless if --enable-static-pie is used to configure glibc.
When glibc is configured with --enable-static-pie, libc.a is compiled
with -fPIE, regardless whether GCC defaults to PIE or not. The same
libc.a can be used to build both static executable and static PIE.
There is no need for separate PIE copy of libc.a.
On x86-64, the normal static sln:
text data bss dec hex filename
625425 8284 5456 639165 9c0bd elf/sln
the static PIE sln:
text data bss dec hex filename
657626 20636 5392 683654 a6e86 elf/sln
The code size is increased by 5% and the binary size is increased by 7%.
Linker requirements to build glibc with --enable-static-pie:
1. Linker supports --no-dynamic-linker to remove PT_INTERP segment from
static PIE.
2. Linker can create working static PIE. The x86-64 linker needs the
fix for
https://sourceware.org/bugzilla/show_bug.cgi?id=21782
The i386 linker needs to be able to convert "movl main@GOT(%ebx), %eax"
to "leal main@GOTOFF(%ebx), %eax" if main is defined locally.
Binutils 2.29 or above are OK for i686 and x86-64. But linker status for
other targets need to be verified.
3. Linker should resolve undefined weak symbols to 0 in static PIE:
https://sourceware.org/bugzilla/show_bug.cgi?id=22269
4. Many ELF backend linkers incorrectly check bfd_link_pic for TLS
relocations, which should check bfd_link_executable instead:
https://sourceware.org/bugzilla/show_bug.cgi?id=22263
Tested on aarch64, i686 and x86-64.
Using GCC 7 and binutils master branch, build-many-glibcs.py with
--enable-static-pie with all patches for static PIE applied have the
following build successes:
PASS: glibcs-aarch64_be-linux-gnu build
PASS: glibcs-aarch64-linux-gnu build
PASS: glibcs-armeb-linux-gnueabi-be8 build
PASS: glibcs-armeb-linux-gnueabi build
PASS: glibcs-armeb-linux-gnueabihf-be8 build
PASS: glibcs-armeb-linux-gnueabihf build
PASS: glibcs-arm-linux-gnueabi build
PASS: glibcs-arm-linux-gnueabihf build
PASS: glibcs-arm-linux-gnueabihf-v7a build
PASS: glibcs-arm-linux-gnueabihf-v7a-disable-multi-arch build
PASS: glibcs-m68k-linux-gnu build
PASS: glibcs-microblazeel-linux-gnu build
PASS: glibcs-microblaze-linux-gnu build
PASS: glibcs-mips64el-linux-gnu-n32 build
PASS: glibcs-mips64el-linux-gnu-n32-nan2008 build
PASS: glibcs-mips64el-linux-gnu-n32-nan2008-soft build
PASS: glibcs-mips64el-linux-gnu-n32-soft build
PASS: glibcs-mips64el-linux-gnu-n64 build
PASS: glibcs-mips64el-linux-gnu-n64-nan2008 build
PASS: glibcs-mips64el-linux-gnu-n64-nan2008-soft build
PASS: glibcs-mips64el-linux-gnu-n64-soft build
PASS: glibcs-mips64-linux-gnu-n32 build
PASS: glibcs-mips64-linux-gnu-n32-nan2008 build
PASS: glibcs-mips64-linux-gnu-n32-nan2008-soft build
PASS: glibcs-mips64-linux-gnu-n32-soft build
PASS: glibcs-mips64-linux-gnu-n64 build
PASS: glibcs-mips64-linux-gnu-n64-nan2008 build
PASS: glibcs-mips64-linux-gnu-n64-nan2008-soft build
PASS: glibcs-mips64-linux-gnu-n64-soft build
PASS: glibcs-mipsel-linux-gnu build
PASS: glibcs-mipsel-linux-gnu-nan2008 build
PASS: glibcs-mipsel-linux-gnu-nan2008-soft build
PASS: glibcs-mipsel-linux-gnu-soft build
PASS: glibcs-mips-linux-gnu build
PASS: glibcs-mips-linux-gnu-nan2008 build
PASS: glibcs-mips-linux-gnu-nan2008-soft build
PASS: glibcs-mips-linux-gnu-soft build
PASS: glibcs-nios2-linux-gnu build
PASS: glibcs-powerpc64le-linux-gnu build
PASS: glibcs-powerpc64-linux-gnu build
PASS: glibcs-tilegxbe-linux-gnu-32 build
PASS: glibcs-tilegxbe-linux-gnu build
PASS: glibcs-tilegx-linux-gnu-32 build
PASS: glibcs-tilegx-linux-gnu build
PASS: glibcs-tilepro-linux-gnu build
and the following build failures:
FAIL: glibcs-alpha-linux-gnu build
elf/sln is failed to link due to:
assertion fail bfd/elf64-alpha.c:4125
This is caused by linker bug and/or non-PIC code in PIE libc.a.
FAIL: glibcs-hppa-linux-gnu build
elf/sln is failed to link due to:
collect2: fatal error: ld terminated with signal 11 [Segmentation fault]
https://sourceware.org/bugzilla/show_bug.cgi?id=22537
FAIL: glibcs-ia64-linux-gnu build
elf/sln is failed to link due to:
collect2: fatal error: ld terminated with signal 11 [Segmentation fault]
FAIL: glibcs-powerpc-linux-gnu build
FAIL: glibcs-powerpc-linux-gnu-soft build
FAIL: glibcs-powerpc-linux-gnuspe build
FAIL: glibcs-powerpc-linux-gnuspe-e500v1 build
elf/sln is failed to link due to:
ld: read-only segment has dynamic relocations.
This is caused by linker bug and/or non-PIC code in PIE libc.a. See:
https://sourceware.org/bugzilla/show_bug.cgi?id=22264
FAIL: glibcs-powerpc-linux-gnu-power4 build
elf/sln is failed to link due to:
findlocale.c:96:(.text+0x22c): @local call to ifunc memchr
This is caused by linker bug and/or non-PIC code in PIE libc.a.
FAIL: glibcs-s390-linux-gnu build
elf/sln is failed to link due to:
collect2: fatal error: ld terminated with signal 11 [Segmentation fault], core dumped
assertion fail bfd/elflink.c:14299
This is caused by linker bug and/or non-PIC code in PIE libc.a.
FAIL: glibcs-sh3eb-linux-gnu build
FAIL: glibcs-sh3-linux-gnu build
FAIL: glibcs-sh4eb-linux-gnu build
FAIL: glibcs-sh4eb-linux-gnu-soft build
FAIL: glibcs-sh4-linux-gnu build
FAIL: glibcs-sh4-linux-gnu-soft build
elf/sln is failed to link due to:
ld: read-only segment has dynamic relocations.
This is caused by linker bug and/or non-PIC code in PIE libc.a. See:
https://sourceware.org/bugzilla/show_bug.cgi?id=22263
Also TLS code sequence in SH assembly syscalls in glibc doesn't match TLS
code sequence expected by ld:
https://sourceware.org/bugzilla/show_bug.cgi?id=22270
FAIL: glibcs-sparc64-linux-gnu build
FAIL: glibcs-sparcv9-linux-gnu build
FAIL: glibcs-tilegxbe-linux-gnu build
FAIL: glibcs-tilegxbe-linux-gnu-32 build
FAIL: glibcs-tilegx-linux-gnu build
FAIL: glibcs-tilegx-linux-gnu-32 build
FAIL: glibcs-tilepro-linux-gnu build
elf/sln is failed to link due to:
ld: read-only segment has dynamic relocations.
This is caused by linker bug and/or non-PIC code in PIE libc.a. See:
https://sourceware.org/bugzilla/show_bug.cgi?id=22263
[BZ #19574]
* INSTALL: Regenerated.
* Makeconfig (real-static-start-installed-name): New.
(pic-default): Updated for --enable-static-pie.
(pie-default): New for --enable-static-pie.
(default-pie-ldflag): Likewise.
(+link-static-before-libc): Replace $(DEFAULT-LDFLAGS-$(@F))
with $(if $($(@F)-no-pie),$(no-pie-ldflag),$(default-pie-ldflag)).
Replace $(static-start-installed-name) with
$(real-static-start-installed-name).
(+prectorT): Updated for --enable-static-pie.
(+postctorT): Likewise.
(CFLAGS-.o): Add $(pie-default).
(CFLAGS-.op): Likewise.
* NEWS: Mention --enable-static-pie.
* config.h.in (ENABLE_STATIC_PIE): New.
* configure.ac (--enable-static-pie): New configure option.
(have-no-dynamic-linker): New LIBC_CONFIG_VAR.
(have-static-pie): Likewise.
Enable static PIE if linker supports --no-dynamic-linker.
(ENABLE_STATIC_PIE): New AC_DEFINE.
(enable-static-pie): New LIBC_CONFIG_VAR.
* configure: Regenerated.
* csu/Makefile (omit-deps): Add r$(start-installed-name) and
gr$(start-installed-name) for --enable-static-pie.
(extra-objs): Likewise.
(install-lib): Likewise.
(extra-objs): Add static-reloc.o and static-reloc.os
($(objpfx)$(start-installed-name)): Also depend on
$(objpfx)static-reloc.o.
($(objpfx)r$(start-installed-name)): New.
($(objpfx)g$(start-installed-name)): Also depend on
$(objpfx)static-reloc.os.
($(objpfx)gr$(start-installed-name)): New.
* csu/libc-start.c (LIBC_START_MAIN): Call _dl_relocate_static_pie
in libc.a.
* csu/libc-tls.c (__libc_setup_tls): Add main_map->l_addr to
initimage.
* csu/static-reloc.c: New file.
* elf/Makefile (routines): Add dl-reloc-static-pie.
(elide-routines.os): Likewise.
(DEFAULT-LDFLAGS-tst-tls1-static-non-pie): Removed.
(tst-tls1-static-non-pie-no-pie): New.
* elf/dl-reloc-static-pie.c: New file.
* elf/dl-support.c (_dl_get_dl_main_map): New function.
* elf/dynamic-link.h (ELF_DURING_STARTUP): Also check
STATIC_PIE_BOOTSTRAP.
* elf/get-dynamic-info.h (elf_get_dynamic_info): Likewise.
* gmon/Makefile (tests): Add tst-gmon-static-pie.
(tests-static): Likewise.
(DEFAULT-LDFLAGS-tst-gmon-static): Removed.
(tst-gmon-static-no-pie): New.
(CFLAGS-tst-gmon-static-pie.c): Likewise.
(CRT-tst-gmon-static-pie): Likewise.
(tst-gmon-static-pie-ENV): Likewise.
(tests-special): Likewise.
($(objpfx)tst-gmon-static-pie.out): Likewise.
(clean-tst-gmon-static-pie-data): Likewise.
($(objpfx)tst-gmon-static-pie-gprof.out): Likewise.
* gmon/tst-gmon-static-pie.c: New file.
* manual/install.texi: Document --enable-static-pie.
* sysdeps/generic/ldsodefs.h (_dl_relocate_static_pie): New.
(_dl_get_dl_main_map): Likewise.
* sysdeps/i386/configure.ac: Check if linker supports static PIE.
* sysdeps/x86_64/configure.ac: Likewise.
* sysdeps/i386/configure: Regenerated.
* sysdeps/x86_64/configure: Likewise.
* sysdeps/mips/Makefile (ASFLAGS-.o): Add $(pie-default).
(ASFLAGS-.op): Likewise.
Support added to identify Sparc M7/T7/S7/M8/T8 processor capability.
Performance tests run on Sparc S7 using new code and old niagara4 code.
Optimizations for memset also apply to bzero as they share code.
For memset/bzero, performance comparison with niagara4 code:
For memset nonzero data,
256-1023 bytes - 60-90% gain (in cache); 5% gain (out of cache)
1K+ bytes - 80-260% gain (in cache); 40-80% gain (out of cache)
For memset zero data (and bzero),
256-1023 bytes - 80-120% gain (in cache), 0% gain (out of cache)
1024+ bytes - 2-4x gain (in cache), 10-35% gain (out of cache)
Tested in sparcv9-*-* and sparc64-*-* targets in both multi and
non-multi arch configurations.
Patrick McGehearty <patrick.mcgehearty@oracle.com>
Adhemerval Zanella <adhemerval.zanella@linaro.org>
* sysdeps/sparc/sparc32/sparcv9/multiarch/Makefile
(sysdeps_routines): Add memset-niagara7.
* sysdeps/sparc/sparc64/multiarch/Makefile (sysdes_rotuines):
Likewise.
* sysdeps/sparc/sparc32/sparcv9/multiarch/memset-niagara7.S: New
file.
* sysdeps/sparc/sparc64/multiarch/memset-niagara7.S: Likewise.
* sysdeps/sparc/sparc64/multiarch/ifunc-impl-list.c
(__libc_ifunc_impl_list): Add __bzero_niagara7 and __memset_niagara7.
* sysdeps/sparc/sparc64/multiarch/ifunc-memset.h (IFUNC_SELECTOR):
Add niagara7 option.
* NEWS: Mention sparc m7 optimized memcpy, mempcpy, memmove, and
memset.
There is a configure option --without-fp that specifies that nofpu
sysdeps directories should be used instead of fpu directories.
For most glibc configurations, this option is of no use: either there
is no valid nofpu variant of that configuration, or there are no fpu
or nofpu sysdeps directories for that processor and so the option does
nothing. For a few configurations, if you are using a soft-float
compiler this option is required, and failing to use it generally
results in compilation errors from inline asm using unavailable
floating-point instructions.
We're moving away from --with-cpu to configuring glibc based on how
the compiler generates code, and it is natural to do so for
--without-fp as well; in most cases the soft-float and hard-float ABIs
are incompatible so you have no hope of building a working glibc with
an inappropriately configured compiler or libgcc.
This patch eliminates --without-fp, replacing it entirely by automatic
configuration based on the compiler. Configurations for which this is
relevant (coldfire / mips / powerpc32 / sh) define a variable
with_fp_cond in their preconfigure fragments (under the same
conditions under which those fragments do anything); this is a
preprocessor conditional which the toplevel configure script then uses
in a test to determine which sysdeps directories to use.
The config.make with-fp variable remains. It's used only by powerpc
(sysdeps/powerpc/powerpc32/Makefile) to add -mhard-float to various
flags variables. For powerpc, -mcpu= options can imply use of
soft-float. That could be an issue if you want to build for
e.g. 476fp, but are using --with-cpu=476 because there isn't a 476fp
sysdeps directory. If in future we eliminate --with-cpu and replace
it entirely by testing the compiler, it would be natural at that point
to eliminate that code as well (as the user should then just use a
compiler defaulting to 476fp and the 476 sysdeps directory would be
used automatically).
Tested for x86_64, and tested with build-many-glibcs.py that installed
shared libraries are unchanged by this patch.
* configure.ac (--with-fp): Remove configure option.
(with_fp_cond): New variable.
(libc_cv_with_fp): New configure test. Use this variable instead
of with_fp.
* configure: Regenerated.
* config.make.in (with-fp): Use @libc_cv_with_fp@.
* manual/install.texi (Configuring and compiling): Remove
--without-fp.
* INSTALL: Regenerated.
* sysdeps/m68k/preconfigure (with_fp_cond): Define for ColdFire.
* sysdeps/mips/preconfigure (with_fp_cond): Define.
* sysdeps/powerpc/preconfigure (with_fp_cond): Define for 32-bit.
* sysdeps/sh/preconfigure (with_fp_cond): Define.
* scripts/build-many-glibcs.py (Context.add_all_configs): Do not
use --without-fp to configure glibc.
On Skylake, bench-sinf reports performance improvement:
Before After Improvement
max 153.996 100.094 54%
min 8.546 6.852 25%
mean 18.1223 11.802 54%
* sysdeps/x86_64/fpu/multiarch/Makefile (libm-sysdep_routines):
Add s_sinf-sse2 and s_sinf-fma.
(CFLAGS-s_sinf-fma.c): New.
* sysdeps/x86_64/fpu/multiarch/s_sinf-fma.c: New file.
* sysdeps/x86_64/fpu/multiarch/s_sinf-sse2.c: Likewise.
* sysdeps/x86_64/fpu/multiarch/s_sinf.c: Likewise.
This patch continues filling out TS 18661-3 support by adding *f64 and
*f32x function aliases, supporting _Float64 and _Float32x, as aliases
for double functions. These types are supported for all glibc
configurations. The API corresponds exactly to that for _Float128 and
_Float64x. _Float32 aliases to float functions remain to be added in
subsequent patches to complete this process (then there are a few
miscellaneous functions in TS 18661-3 to implement that aren't simply
versions of existing functions for new types).
The patch enables the feature in bits/floatn-common.h, adds symbol
versions and documentation with updates to ABI baselines, and arranges
for the libm functions for the new types to be tested. As with the
_Float64x changes there are some x86 ulps updates because of header
inlines not used for the new types (and one other change to the
non-multiarch libm-test-ulps, which I suppose comes from using a
different compiler version / configuration from when it was last
regenerated).
Tested for x86_64 and x86, and with build-many-glibcs.py, with both
GCC 6 and GCC 7.
* bits/floatn-common.h (__HAVE_FLOAT64): Define to 1.
(__HAVE_FLOAT32X): Likewise.
* manual/math.texi (Mathematics): Document support for _Float64
and _Float32x.
* math/Makefile (test-types): Add float64 and float32x.
* math/Versions (GLIBC_2.27): Add _Float64 and _Float32x
functions.
* stdlib/Versions (GLIBC_2.27): Likewise.
* wcsmbs/Versions (GLIBC_2.27): Likewise.
* sysdeps/unix/sysv/linux/aarch64/libc.abilist: Update.
* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/alpha/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/alpha/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/arm/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/arm/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/hppa/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/hppa/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/i386/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/i386/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/ia64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/ia64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/microblaze/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/microblaze/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/nios2/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/nios2/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sh/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sh/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/tile/tilepro/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Likewise.
* sysdeps/i386/fpu/libm-test-ulps: Likewise.
* sysdeps/i386/i686/fpu/multiarch/libm-test-ulps: Likewise.
This adds system call wrappers for pkey_alloc, pkey_free, pkey_mprotect,
and x86-64 implementations of pkey_get and pkey_set, which abstract over
the PKRU CPU register and hide the actual number of memory protection
keys supported by the CPU. pkey_mprotect with a -1 key is implemented
using mprotect, so it will work even if the kernel does not support the
pkey_mprotect system call.
The system call wrapers use unsigned int instead of unsigned long for
parameters, so that no special treatment for x32 is needed. The flags
argument is currently unused, and the access rights bit mask is limited
to two bits by the current PKRU register layout anyway.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
There is a subtle non-determinism when building glibc.
This depends on whether the glibc is built using the distibuted
file intl/plural.c or built using the generated file intl/plural.c.
These two files (intl/plural.c generated vs. distributed) are slightly
different, hence we may end up with slightly different libraries.
Originally, having "bison" installed was optional. So if "bison" was
not present, we always built libraries with the distributed plural.c.
If bison was installed, we *** may have *** replaced the distributed
file plural.c with a new plural.c generated from plural.y. if the
timestamps triggered this rule:
plural.c plural.y
$(BISON) $(BISONFLAGS) $@ $^
Given that timestamps are not preserved in GIT repositories, the above
rule is not reliable without explicitly touching plural.c or plural.y.
In other words, the rule may or may not have fired.
In summary: there are two distinct sources of non-determinism:
1. Having "bison" installed or not
2. Having "bison" installed but timestamps poorly defined.
This patch fixes this by requiring "bison" being installed
and by always generating intl/plural.c from intl/plural.y.
(This is achieved by simply removing checked-in intl/plural.c)
[BZ #22432]
* configure.ac (BISON): Require to be present.
* configure: Regenerated.
* intl/Makefile (generated): Add plural.c.
[$(BISON) != no]: Make code unconditional.
(plural.c): Change rule to $(objpfx)plural.c.
($(objpfx)plural.o): Depend on $(objpfx)plural.c.
* intl/plural.c: Remove.
* manual/install.texi (Tools for Compilation): Document bison as
required.
* INSTALL: Regenerated.
This patch continues filling out TS 18661-3 support by adding *f64x
function aliases on platforms with _Float64x support. (It so happens
the set of such platforms is exactly the same as the set of platforms
with _Float128 support, although on x86_64, x86 and ia32 the _Float64x
format is Intel extended rather than binary128.) The API provided
corresponds exactly to that provided for _Float128, mostly coming from
TS 18661-3. As these functions always alias those for another type
(long double, _Float128 or both), __* function names are not provided,
as in other cases of alias types.
Given the preparation done in previous patches, this one just enables
the feature via Makeconfig and bits/floatn.h, adds symbol versions,
and updates documentation and ABI baselines. The symbol versions are
present unconditionally as GLIBC_2.27 in the relevant Versions files,
as it's OK for those to specify versions for functions that may not be
present in some configurations; no additional complexity is needed
unless in future some configuration gains support for this type that
didn't have such support in 2.27. The Makeconfig additions for ia64
and x86 aren't strictly needed, as those configurations also get
float64x-alias-fcts definitions from
sysdeps/ieee754/float128/Makeconfig, but still seem appropriate given
that _Float64x is not _Float128 for those configurations.
A libm-test-ulps update for x86 is included. This is because
bits/mathinline.h does not have _Float64x support added and for two
functions the use of out-of-line functions results in increased ulps
(ifloat64x shares ulps with ildouble / ifloat128 as appropriate).
Given that we'd like generally to eliminate bits/mathinline.h
optimizations, preferring to have such optimizations in GCC instead,
it seems reasonable not to add such support there for new types. GCC
support for _FloatN / _FloatNx built-in functions is limited, but has
been improved in GCC 8, and at some point I hope the full set of libm
built-in functions in GCC, and other optimizations with
per-floating-type aspects, will be enabled for all _FloatN / _FloatNx
types.
Tested for x86_64 and x86, and with build-many-glibcs.py, with both
GCC 6 and GCC 7.
* sysdeps/ia64/Makeconfig (float64x-alias-fcts): New variable.
* sysdeps/ieee754/float128/Makeconfig (float64x-alias-fcts):
Likewise.
* sysdeps/ieee754/ldbl-128/Makeconfig (float64x-alias-fcts):
Likewise.
* sysdeps/x86/Makeconfig: New file.
* bits/floatn-common.h (__HAVE_FLOAT64X): Remove macro.
(__HAVE_FLOAT64X_LONG_DOUBLE): Likewise.
* bits/floatn.h (__HAVE_FLOAT64X): New macro.
(__HAVE_FLOAT64X_LONG_DOUBLE): Likewise.
* sysdeps/ia64/bits/floatn.h (__HAVE_FLOAT64X): Likewise.
(__HAVE_FLOAT64X_LONG_DOUBLE): Likewise.
* sysdeps/ieee754/ldbl-128/bits/floatn.h (__HAVE_FLOAT64X):
Likewise.
(__HAVE_FLOAT64X_LONG_DOUBLE): Likewise.
* sysdeps/mips/ieee754/bits/floatn.h (__HAVE_FLOAT64X): Likewise.
(__HAVE_FLOAT64X_LONG_DOUBLE): Likewise.
* sysdeps/powerpc/bits/floatn.h (__HAVE_FLOAT64X): Likewise.
(__HAVE_FLOAT64X_LONG_DOUBLE): Likewise.
* sysdeps/x86/bits/floatn.h (__HAVE_FLOAT64X): Likewise.
(__HAVE_FLOAT64X_LONG_DOUBLE): Likewise.
* manual/math.texi (Mathematics): Document support for _Float64x.
* math/Versions (GLIBC_2.27): Add _Float64x functions.
* stdlib/Versions (GLIBC_2.27): Likewise.
* wcsmbs/Versions (GLIBC_2.27): Likewise.
* sysdeps/unix/sysv/linux/aarch64/libc.abilist: Update.
* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/alpha/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/alpha/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/i386/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/i386/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/ia64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/ia64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist:
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Likewise.
* sysdeps/i386/fpu/libm-test-ulps: Likewise.
* sysdeps/i386/i686/fpu/multiarch/libm-test-ulps: Likewise.
The system call is somewhat obscure because it is closely related
to file descriptor sealing. However, it is also the recommended
way to create alias mappings, which is why it has more general use.
No emulation is provided. Except for the name of the
/proc/self/fd links, it would be possible to implement an
approximation using O_TMPFILE and tmpfs, but this does not appear
to be worth the added complexity.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
This patch, relative to a tree with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html> (pending
review) applied, obsoletes p_secstodate, making the underlying
function __p_secstodate into a compat symbol not available for new
binaries or ports. The calls in ns_print.c (part of incomplete
handling of TKEY) are changed to use %lu to print times instead of
trying to pretty-print the times any more.
Tested for x86_64.
* resolv/res_debug.c (p_secstodate): Condition definition on
[SHLIB_COMPAT (libresolv, GLIBC_2_0, GLIBC_2_27)]. Define
directly as __p_secstodate, and as a compat symbol. Do not use
libresolv_hidden_def.
* resolv/resolv.h (p_secstodate): Remove macro and function
declaration.
* resolv/ns_print.c (ns_sprintrrf): Print times with %lu, not
using p_secstodate.
* include/resolv.h (__p_secstodate): Do not use
libresolv_hidden_proto.
* resolv/Makefile (tests): Move tst-p_secstodate to ....
(tests-internal): ... here.
* resolv/tst-p_secstodate.c: Include <shlib-compat.h>. Condition
all contents on [TEST_COMPAT (libresolv, GLIBC_2_0, GLIBC_2_27)]
and declare and use __p_secstodate and use compat_symbol_reference
in that case.
[!TEST_COMPAT (libresolv, GLIBC_2_0, GLIBC_2_27)] (do_test): Add
implementation returning 77.
Update all sourceware links to https. The website redirects
everything to https anyway so let the web server do a bit less work.
The only reference that remains unchanged is the one in the old
ChangeLog, since it didn't seem worth changing it.
* NEWS: Update sourceware link to https.
* configure.ac: Likewise.
* crypt/md5test-giant.c: Likewise.
* dlfcn/bug-atexit1.c: Likewise.
* dlfcn/bug-atexit2.c: Likewise.
* localedata/README: Likewise.
* malloc/tst-mallocfork.c: Likewise.
* manual/install.texi: Likewise.
* nptl/tst-pthread-getattr.c: Likewise.
* stdio-common/tst-fgets.c: Likewise.
* stdio-common/tst-fwrite.c: Likewise.
* sunrpc/Makefile: Likewise.
* sysdeps/arm/armv7/multiarch/memcpy_impl.S: Likewise.
* wcsmbs/tst-mbrtowc2.c: Likewise.
* configure: Regenerate.
* INSTALL: Regenerate.
This commit adds a "subheaps" field to the malloc_info output that
shows the number of heaps that were allocated to extend a non-main
arena.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
res_hnok rejected some host names used on the Internet, such as
www-.example.com. res_hnok and res_dnok failed to perform basic syntax
checking on DNS domain names.
Also fix res_mailok, res_ownok.
This patch adds support for *f128 function aliases on platforms where
long double has the binary128 format (and thus GCC 7 provides the
_Float128 type with the same ABI as long double but as a distinct type
in terms of C type compatibility). This is the same API as provided
in glibc 2.26 for powerpc64le / x86_64 / x86 / ia64 where _Float128
has a different format from long double, with the bulk of the API
coming from TS 18661-3. All the functions alias the corresponding
long double functions, and __* function names are not provided since
those are only needed once for each floating-point format, not more
than once for different types with the same format (so for example,
-ffinite-math-only maps foof128 to __fool_finite, while type-generic
macros end up calling e.g. __issignalingl for _Float128 arguments on
such platforms).
The preparation for this feature was done in previous patches, so this
one just needs to add the relevant makefile and header definitions,
and update macro definitions of libm_alias_ldouble_other_r, to turn on
the feature, and update documentation and ABI baselines.
Tested (a) for x86_64, (b) for aarch64, (c) with build-many-glibcs.py
with both GCC 6 and GCC 7.
* sysdeps/ieee754/ldbl-128/Makeconfig: New file.
* sysdeps/ieee754/ldbl-128/bits/floatn.h: Likewise.
* sysdeps/ieee754/ldbl-128/float128-abi.h: Likewise.
* sysdeps/generic/libm-alias-ldouble.h: Include <bits/floatn.h>.
[__HAVE_FLOAT128 && !__HAVE_DISTINCT_FLOAT128]
(libm_alias_ldouble_other_r): Also create _Float128 alias.
* sysdeps/ieee754/ldbl-opt/libm-alias-ldouble.h: Include
<bits/floatn.h>.
[__HAVE_FLOAT128 && !__HAVE_DISTINCT_FLOAT128]
(libm_alias_ldouble_other_r): Also create _Float128 alias.
* manual/math.texi (Mathematics): Document additional architecture
support for _Float128.
* sysdeps/unix/sysv/linux/aarch64/libc.abilist: Update.
* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/alpha/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/alpha/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Likewise.
glibc has an add-ons mechanism to allow additional software to be
integrated into the glibc build. Such add-ons may be within the glibc
source tree, or outside it at a path passed to the --enable-add-ons
configure option.
localedata and crypt were once add-ons, distributed in separate
release tarballs, but long since stopped using that mechanism.
Linuxthreads was always an add-on. Ports spent some time as an add-on
with separate release tarballs, then was first moved into the glibc
source tree, then had its sysdeps files moved into the main sysdeps
hierarchy so the add-ons mechanism was no longer used. NPTL spent
some time as an add-on in the main glibc tree before stopping using
the add-on mechanism. libidn used to have separate release tarballs
but no longer does so, but still uses the add-ons mechanism within the
glibc source tree. Various other software has supported building with
the add-ons mechanism at times in the past, but I don't think any is
still widely used.
Add-ons involve significant, little-used complexity in the glibc build
system, and make it hard to understand what the space of possible
glibc configurations is. This patch removes the add-ons mechanism.
libidn is now built via the Subdirs mechanism to cause any
configuration using sysdeps/unix/inet to build libidn; HAVE_LIBIDN
(which effectively means shared libraries are available) is now
defined via sysdeps/unix/inet/configure. Various references to
add-ons around the source tree are removed (in the case of maint.texi,
the example list of sysdeps directories is still very out of date).
Externally maintained ports should now put their files in the normal
sysdeps directory structure rather than being arranged as add-ons;
they probably need to change e.g. elf.h anyway, rather than actually
being able to work just as a drop-in subtree. Hurd libpthread should
be arranged similarly to NPTL, so some files might go in a
hurd-pthreads (or similar) top-level directory in glibc, while sysdeps
files should go in the normal sysdeps directory structure (possibly in
hurd or hurd-pthreads subdirectories, just as there are nptl
subdirectories in the sysdeps tree).
Tested for x86_64, and with build-many-glibcs.py.
* configure.ac (--enable-add-ons): Remove option.
(machine): Do not mention add-ons in comment.
(LIBC_PRECONFIGURE): Likewise.
(add_ons): Remove variable and sanity checks and logic to locate
add-ons.
(add_ons_automatic): Remove variable.
(configured_add_ons): Likewise.
(add_ons_sfx): Likewise.
(add_ons_pfx): Likewise.
(add_on_subdirs): Likewise.
(sysnames_add_ons): Likewise. Remove loop over add-ons and
consideration of add-ons in Implies handling.
(sysdeps_add_ons): Likewise.
* configure: Regenerated.
* libidn/configure.ac: Remove.
* libidn/configure: Likewise.
* sysdeps/unix/inet/configure.ac: New file.
* sysdeps/unix/inet/configure: New generated file.
* sysdeps/unix/inet/Subdirs: Add libidn.
* Makeconfig (sysdeps-srcdirs): Remove variable.
(+sysdep_dirs): Do not include $(sysdeps-srcdirs).
($(common-objpfx)config.status): Do not depend on add-on files.
($(common-objpfx)shlib-versions.v.i): Do not mention add-ons in
comment.
(all-subdirs): Do not include $(add-on-subdirs).
* Makefile (dist-prepare): Do not use $(sysdeps-add-ons).
* config.make.in (add-ons): Remove variable.
(add-on-subdirs): Likewise.
(sysdeps-add-ons): Likewise.
* manual/Makefile (add-chapters): Remove.
($(objpfx)texis): Do not depend on $(add-chapters).
(nonexamples): Do not handle $(add-chapters).
(examples): Do not handle $(add-ons).
(chapters.% top-menu.%): Do not pass '$(add-chapters)' to
libc-texinfo.sh.
* manual/install.texi (Installation): Do not mention add-ons.
(--enable-add-ons): Do not document configure option.
* INSTALL: Regenerated.
* manual/libc-texinfo.sh: Do not handle $2 add-ons argument.
* manual/maint.texi (Hierarchy Conventions): Do not mention
add-ons.
* scripts/build-many-glibcs.py (Glibc.build_glibc): Do not use
--enable-add-ons.
* scripts/gen-sorted.awk: Do not handle Subdirs files from
add-ons.
* scripts/test-installation.pl: Do not handle glibc-compat add-on.
* sysdeps/nptl/Makeconfig: Do not mention add-ons in comment.
without wrapper on aarch64:
powf reciprocal-throughput: 4.2x faster
powf latency: 2.6x faster
old worst-case error: 1.11 ulp
new worst-case error: 0.82 ulp
aarch64 .text size: -780 bytes
aarch64 .rodata size: +144 bytes
powf(x,y) is implemented as exp2(y*log2(x)) with the same algorithms
that are used in exp2f and log2f, except that the log2f polynomial is
larger for extra precision and its output (and exp2f input) may be
scaled by a power of 2 (POWF_SCALE) to simplify the argument reduction
step of exp2 (possible when efficient round and convert toint operation
is available).
The special case handling tries to minimize the checks in the hot path.
When the input of exp2_inline is checked, int arithmetics is used as
that was faster on the tested aarch64 cores.
* math/Makefile (type-float-routines): Add e_powf_log2_data.
* sysdeps/ieee754/flt-32/e_powf.c: New implementation.
* sysdeps/ieee754/flt-32/e_powf_log2_data.c: New file.
* sysdeps/ieee754/flt-32/math_config.h (__powf_log2_data): Define.
(issignalingf_inline): Likewise.
(POWF_LOG2_TABLE_BITS): Likewise.
(POWF_LOG2_POLY_ORDER): Likewise.
(POWF_SCALE_BITS): Likewise.
(POWF_SCALE): Likewise.
* sysdeps/i386/fpu/e_powf_log2_data.c: New file.
* sysdeps/ia64/fpu/e_powf_log2_data.c: New file.
* sysdeps/m68k/m680x0/fpu/e_powf_log2_data.c: New file.
Similar to the new logf: double precision arithmetics and a small
lookup table is used. The argument reduction step is the same as in
the new logf.
without wrapper on aarch64:
log2f reciprocal-throughput: 2.3x faster
log2f latency: 2.1x faster
old worst case error: 1.72 ulp
new worst case error: 0.75 ulp
aarch64 .text size: -252 bytes
aarch64 .rodata size: +244 bytes
* math/Makefile (type-float-routines): Add e_log2f_data.
* sysdeps/ieee754/flt-32/e_log2f.c: New implementation.
* sysdeps/ieee754/flt-32/e_log2f_data.c: New file.
* sysdeps/ieee754/flt-32/math_config.h (__log2f_data): Define.
(LOG2F_TABLE_BITS, LOG2F_POLY_ORDER): Define.
* sysdeps/i386/fpu/e_log2f_data.c: New file.
* sysdeps/ia64/fpu/e_log2f_data.c: New file.
* sysdeps/m68k/m680x0/fpu/e_log2f_data.c: New file.
without wrapper on aarch64:
logf reciprocal-throughput: 2.2x faster
logf latency: 1.9x faster
old worst case error: 0.89 ulp
new worst case error: 0.82 ulp
aarch64 .text size: -356 bytes
aarch64 .rodata size: +240 bytes
Uses double precision arithmetics and a lookup table to allow smaller
polynomial and avoid the use of division.
Data is in a separate translation unit with fixed layout to prevent the
compiler generating suboptimal literal access.
Errors are handled inline according to POSIX rules, but this patch
keeps the wrapper with SVID compatible error handling.
Needs libm-test-ulps adjustment for clogf in non-nearest rounding mode.
* math/Makefile (type-float-routines): Add e_logf_data.
* sysdeps/ieee754/flt-32/e_logf.c: New implementation.
* sysdeps/ieee754/flt-32/e_logf_data.c: New file.
* sysdeps/ieee754/flt-32/math_config.h (__logf_data): Define.
(LOGF_TABLE_BITS, LOGF_POLY_ORDER): Define.
* sysdeps/i386/fpu/e_logf_data.c: New file.
* sysdeps/ia64/fpu/e_logf_data.c: New file.
* sysdeps/m68k/m680x0/fpu/e_logf_data.c: New file.
Based on new expf and exp2f code from
https://github.com/ARM-software/optimized-routines/
with wrapper on aarch64:
expf reciprocal-throughput: 2.3x faster
expf latency: 1.7x faster
without wrapper on aarch64:
expf reciprocal-throughput: 3.3x faster
expf latency: 1.7x faster
without wrapper on aarch64:
exp2f reciprocal-throughput: 2.8x faster
exp2f latency: 1.3x faster
libm.so size on aarch64:
.text size: -152 bytes
.rodata size: -1740 bytes
expf/exp2f worst case nearest rounding error: 0.502 ulp
worst case non-nearest rounding error: 1 ulp
Error checks are inline and errno setting is in separate tail called
functions, but the wrappers are kept in this patch to handle the
_LIB_VERSION==_SVID_ case. (So e.g. errno is set twice for expf calls
and once for __expf_finite calls on targets where the new code is used.)
Double precision arithmetics is used which is expected to be faster on
most targets (including soft-float) than using single precision and it
is easier to get good precision result with it.
Const data is kept in a separate translation unit which complicates
maintenance a bit, but is expected to give good code for literal loads
on most targets and allows sharing data across expf, exp2f and powf.
(This data is disabled on i386, m68k and ia64 which have their own
expf, exp2f and powf code.)
Some details may need target specific tweaks:
- best convert and round to int operation in the arg reduction may be
different across targets.
- code was optimized on fma target, optimal polynomial eval may be
different without fma.
- gcc does not always generate good code for fp bit representation
access via unions or it may be inherently slow on some targets.
The libm-test-ulps will need adjustment because..
- The argument reduction ideally uses nearest rounded rint, but that is
not efficient on most targets, so the polynomial can get evaluated on a
wider interval in non-nearest rounding mode making 1 ulp errors common
in that case.
- The polynomial is evaluated such that it may have 1 ulp error on
negative tiny inputs with upward rounding.
* math/Makefile (type-float-routines): Add math_errf and e_exp2f_data.
* sysdeps/aarch64/fpu/math_private.h (TOINT_INTRINSICS): Define.
(roundtoint, converttoint): Likewise.
* sysdeps/ieee754/flt-32/e_expf.c: New implementation.
* sysdeps/ieee754/flt-32/e_exp2f.c: New implementation.
* sysdeps/ieee754/flt-32/e_exp2f_data.c: New file.
* sysdeps/ieee754/flt-32/math_config.h: New file.
* sysdeps/ieee754/flt-32/math_errf.c: New file.
* sysdeps/ieee754/flt-32/t_exp2f.h: Remove.
* sysdeps/i386/fpu/e_exp2f_data.c: New file.
* sysdeps/i386/fpu/math_errf.c: New file.
* sysdeps/ia64/fpu/e_exp2f_data.c: New file.
* sysdeps/ia64/fpu/math_errf.c: New file.
* sysdeps/m68k/m680x0/fpu/e_exp2f_data.c: New file.
* sysdeps/m68k/m680x0/fpu/math_errf.c: New file.
This patch adds SSE4.1 versions of trunc and truncf, using the roundsd
/ roundss instructions, similar to the versions of ceil, floor, rint
and nearbyint functions we already have. In my testing with the glibc
benchtests these are about 30% faster than the C versions for double,
20% faster for float.
Tested for x86_64.
[BZ #20142]
* sysdeps/x86_64/fpu/multiarch/Makefile (libm-sysdep_routines):
Add s_trunc-c, s_truncf-c, s_trunc-sse4_1 and s_truncf-sse4_1.
* sysdeps/x86_64/fpu/multiarch/s_trunc-c.c: New file.
* sysdeps/x86_64/fpu/multiarch/s_trunc-sse4_1.S: Likewise.
* sysdeps/x86_64/fpu/multiarch/s_trunc.c: Likewise.
* sysdeps/x86_64/fpu/multiarch/s_truncf-c.c: Likewise.
* sysdeps/x86_64/fpu/multiarch/s_truncf-sse4_1.S: Likewise.
* sysdeps/x86_64/fpu/multiarch/s_truncf.c: Likewise.
This patch obsoletes the pow10, pow10f and pow10l functions (makes
them into compat symbols, not available for new ports or static
linking). The exp10 names for these functions are standardized (in TS
18661-4) and were added in the same glibc version (2.1) as pow10 so
source code can change to use them without any loss of portability.
Since pow10 is deliberately not provided for _Float128, only exp10,
this slightly simplifies moving to the new wrapper templates in the
!LIBM_SVID_COMPAT case, by avoiding needing to arrange for pow10,
pow10f and pow10l to be defined by those templates.
Tested for x86_64, and with build-many-glibcs.py.
* manual/math.texi (pow10): Do not document.
(pow10f): Likewise.
(pow10l): Likewise.
* math/bits/mathcalls.h [__USE_GNU] (pow10): Do not declare.
* math/bits/math-finite.h [__USE_GNU] (pow10): Likewise.
* math/libm-test-exp10.inc (pow10_test): Remove.
(do_test): Do not call pow10.
* math/w_exp10_compat.c (pow10): Make into compat symbol.
[NO_LONG_DOUBLE] (pow10l): Likewise.
* math/w_exp10f_compat.c (pow10f): Likewise.
* math/w_exp10l_compat.c (pow10l): Likewise.
* sysdeps/ia64/fpu/e_exp10.S: Include <shlib-compat.h>.
(pow10): Make into compat symbol.
* sysdeps/ia64/fpu/e_exp10f.S: Include <shlib-compat.h>.
(pow10f): Make into compat symbol.
* sysdeps/ia64/fpu/e_exp10l.S: Include <shlib-compat.h>.
(pow10l): Make into compat symbol.
* sysdeps/ieee754/ldbl-opt/Makefile (libnldbl-calls): Remove
pow10.
(CFLAGS-nldbl-pow10.c): Remove variable..
* sysdeps/ieee754/ldbl-opt/nldbl-pow10.c: Remove file.
* sysdeps/ieee754/ldbl-opt/w_exp10_compat.c (pow10l): Condition on
[SHLIB_COMPAT (libm, GLIBC_2_1, GLIBC_2_27)].
* sysdeps/ieee754/ldbl-opt/w_exp10l_compat.c (compat_symbol):
Undefine and redefine.
(pow10l): Make into compat symbol.
* sysdeps/aarch64/libm-test-ulps: Remove pow10 ulps.
* sysdeps/alpha/fpu/libm-test-ulps: Likewise.
* sysdeps/arm/libm-test-ulps: Likewise.
* sysdeps/hppa/fpu/libm-test-ulps: Likewise.
* sysdeps/i386/fpu/libm-test-ulps: Likewise.
* sysdeps/i386/i686/fpu/multiarch/libm-test-ulps: Likewise.
* sysdeps/microblaze/libm-test-ulps: Likewise.
* sysdeps/mips/mips32/libm-test-ulps: Likewise.
* sysdeps/mips/mips64/libm-test-ulps: Likewise.
* sysdeps/nios2/libm-test-ulps: Likewise.
* sysdeps/powerpc/fpu/libm-test-ulps: Likewise.
* sysdeps/powerpc/nofpu/libm-test-ulps: Likewise.
* sysdeps/s390/fpu/libm-test-ulps: Likewise.
* sysdeps/sh/libm-test-ulps: Likewise.
* sysdeps/sparc/fpu/libm-test-ulps: Likewise.
* sysdeps/tile/libm-test-ulps: Likewise.
* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
This patch completes the ucontext.h namespace fixes by fixing issues
related to the use of struct sigcontext as mcontext_t, and inclusion
of <bits/sigcontext.h> even when struct sigcontext is not so used.
Inclusion of <bits/sigcontext.h> by <sys/ucontext.h> is removed; the
way to get the sigcontext structure is by including <signal.h> (in a
context where __USE_MISC is defined); the sysdeps/generic version of
sys/ucontext.h keeps the inclusion by necessity, with a comment about
how this is not namespace-clean, but the only configuration that used
it, MicroBlaze, gets its own version of the header in this patch.
Where mcontext_t was typedefed to struct sigcontext, the contents of
struct sigcontext are inserted (with appropriate namespace handling to
prefix fields with __ when __USE_MISC is not defined); review should
check that this has been done correctly in each case, whether the
definition of struct sigcontext comes from glibc headers or from the
Linux kernel. This changes C++ name mangling on affected
architectures (which do not include x86_64/x86).
Tested for x86_64, and with build-many-glibcs.py.
2017-08-14 Joseph Myers <joseph@codesourcery.com>
[BZ #21457]
* sysdeps/arm/sys/ucontext.h: Do not include <bits/sigcontext.h>.
* sysdeps/generic/sys/ucontext.h: Add comment about use of struct
sigcontext and namespace requirements.
* sysdeps/i386/sys/ucontext.h: Do not include <bits/sigcontext.h>.
* sysdeps/m68k/sys/ucontext.h: Likewise.
* sysdeps/mips/sys/ucontext.h: Likewise. Include <bits/types.h>.
* sysdeps/unix/sysv/linux/aarch64/sys/ucontext.h: Do not include
<bits/sigcontext.h>.
(__ctx): Define earlier.
(mcontext_t): Define structure contents rather than using struct
sigcontext.
* sysdeps/unix/sysv/linux/aarch64/ucontext_i.sym (oEXTENSION): Use
__glibc_reserved1 instead of __reserved.
* sysdeps/unix/sysv/linux/alpha/sys/ucontext.h: Do not include
<bits/sigcontext.h>.
(__ctx): Define earlier.
(mcontext_t): Define structure contents rather than using struct
sigcontext.
* sysdeps/unix/sysv/linux/alpha/ucontext-offsets.sym: Use
mcontext_t instead of struct sigcontext.
* sysdeps/unix/sysv/linux/arm/sys/ucontext.h: Do not include
<bits/sigcontext.h>.
(__ctx): Define earlier.
(mcontext_t): Define structure contents rather than using struct
sigcontext.
* sysdeps/unix/sysv/linux/hppa/sys/ucontext.h: Do not include
<bits/sigcontext.h>.
(__ctx): Define earlier.
(mcontext_t): Define structure contents rather than using struct
sigcontext.
* sysdeps/unix/sysv/linux/ia64/makecontext.c (__makecontext): Use
mcontext_t instead of struct sigcontext.
* sysdeps/unix/sysv/linux/ia64/sigcontext-offsets.sym: Use
mcontext_t instead of struct sigcontext.
* sysdeps/unix/sysv/linux/ia64/sys/ucontext.h: Do not include
<bits/sigcontext.h>.
(__ctx): New macro.
(struct __ia64_fpreg_mcontext): New type.
(mcontext_t): Define structure contents rather than using struct
sigcontext.
(_SC_GR0_OFFSET): Use mcontext_t instead of struct sigcontext.
(uc_sigmask): Define using __ctx.
(uc_stack): Likewise.
* sysdeps/unix/sysv/linux/ia64/sys/procfs.h: Include
<bits/sigcontext.h>.
* sysdeps/unix/sysv/linux/ia64/sys/ptrace.h: Likewise.
* sysdeps/unix/sysv/linux/m68k/sys/ucontext.h: Do not include
<bits/sigcontext.h>.
* sysdeps/unix/sysv/linux/microblaze/sys/ucontext.h: New file.
* sysdeps/unix/sysv/linux/mips/sys/ucontext.h: Do not include
<bits/sigcontext.h>.
* sysdeps/unix/sysv/linux/nios2/sys/ucontext.h: Do not include
<bits/sigcontext.h>.
* sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h: Do not include
<bits/sigcontext.h>.
* sysdeps/unix/sysv/linux/s390/sys/ucontext.h: Do not include
<bits/sigcontext.h>.
* sysdeps/unix/sysv/linux/sh/sys/ucontext.h: Do not include
<bits/sigcontext.h>.
* sysdeps/unix/sysv/linux/sparc/sys/ucontext.h: Do not include
<bits/sigcontext.h>.
* sysdeps/unix/sysv/linux/tile/sys/ucontext.h: Do not include
<bits/sigcontext.h>.
(__ctx): Define earlier.
(mcontext_t): Define structure contents rather than using struct
sigcontext.
* sysdeps/unix/sysv/linux/x86/sys/ucontext.h: Do not include
<bits/sigcontext.h>. Include <bits/types.h>.
* conform/Makefile (test-xfail-XPG42/signal.h/conform): Remove.
(test-xfail-XPG42/sys/wait.h/conform): Likewise.
(test-xfail-XPG42/ucontext.h/conform): Likewise.
(test-xfail-UNIX98/signal.h/conform): Likewise.
(test-xfail-UNIX98/sys/wait.h/conform): Likewise.
(test-xfail-UNIX98/ucontext.h/conform): Likewise.
(test-xfail-XOPEN2K/signal.h/conform): Likewise.
(test-xfail-XOPEN2K/sys/wait.h/conform): Likewise.
(test-xfail-XOPEN2K/ucontext.h/conform): Likewise.
(test-xfail-POSIX2008/signal.h/conform): Likewise.
(test-xfail-POSIX2008/sys/wait.h/conform): Likewise.
(test-xfail-XOPEN2K8/signal.h/conform): Likewise.
(test-xfail-XOPEN2K8/sys/wait.h/conform): Likewise.
This patch obsoletes support for SVID libm error handling (the system
where a user-defined function matherr is called on a libm function
error; only enabled if you also set _LIB_VERSION = _SVID_ or
_LIB_VERSION = _XOPEN_) and the use of the _LIB_VERSION global
variable to control libm error handling. matherr and _LIB_VERSION are
made into compat symbols, not supported for new ports or for static
linking. The libieee.a object file (which sets _LIB_VERSION = _IEEE_,
so disabling errno setting for some functions) is also removed, and
all the related definitions are removed from math.h.
The manual already recommends against using matherr, and it's already
not supported for _Float128 functions (those use new wrappers that
don't support matherr, only errno) - this patch means that it becomes
possible to e.g. add sinf32 as an alias to sinf without that resulting
in undesired matherr support in sinf32 for existing glibc ports.
matherr support is not part of any standard supported by glibc (it was
removed in XPG4).
Because matherr is a function to be defined by the user, of course
user programs defining such a function will still continue to link; it
just quietly won't be used. If they try to write to the library's
copy of _LIB_VERSION to enable SVID error handling, however, they will
get a link error (but if they define their own _LIB_VERSION variable,
they won't).
I expect the most likely case of build failures from this patch to be
programs with unconditional cargo-culted uses of -lieee (based on a
notion of "I want IEEE floating point", not any actual requirement for
that library).
Ideally, the new-port-or-static-linking case would use the new
wrappers used for _Float128. This is not implemented in this patch,
because of the complication of architecture-specific (powerpc32 and
sparc) sqrt wrappers that use _LIB_VERSION and __kernel_standard
directly. Thus, the old wrappers and __kernel_standard are still
built unconditionally, and _LIB_VERSION still exists in static libm.
But when the old wrappers and __kernel_standard are built in the
non-compat case, _LIB_VERSION and matherr are defined as macros so
code to support those features isn't actually built into static libm
or new ports' shared libm after this patch.
I intend to move to the new wrappers for static libm and new ports in
followup patches. I believe the sqrt wrappers for powerpc32 and sparc
can reasonably be removed. GCC already optimizes the normal case of
sqrt by generating code that uses a hardware instruction and only
calls the sqrt function if the argument was negative (if
-fno-math-errno, of course, it just uses the hardware instruction
without any check for negative argument being needed). Thus those
wrappers will only actually get called in the case of negative
arguments, which is not a case it makes sense to optimize for. But
even without removing the powerpc32 and sparc wrappers it should still
be possible to move to the new wrappers for static libm and new ports,
just without having those dubious architecture-specific optimizations
in static libm.
Everything said about matherr equally applies to matherrf and matherrl
(IA64-specific, undocumented), except that the structure of IA64 libm
means it won't be converted to using the new wrappers (it doesn't use
the old ones either, but its own error-handling code instead).
As with other tests of compat symbols, I expect test-matherr and
test-matherr-2 to need to become appropriately conditional once we
have a system for disabling such tests for ports too new to have the
relevant symbols.
Tested for x86_64 and x86, and with build-many-glibcs.py.
* math/math.h [__USE_MISC] (_LIB_VERSION_TYPE): Remove.
[__USE_MISC] (_LIB_VERSION): Likewise.
[__USE_MISC] (struct exception): Likewise.
[__USE_MISC] (matherr): Likewise.
[__USE_MISC] (DOMAIN): Likewise.
[__USE_MISC] (SING): Likewise.
[__USE_MISC] (OVERFLOW): Likewise.
[__USE_MISC] (UNDERFLOW): Likewise.
[__USE_MISC] (TLOSS): Likewise.
[__USE_MISC] (PLOSS): Likewise.
[__USE_MISC] (HUGE): Likewise.
[__USE_XOPEN] (MAXFLOAT): Define even if [__USE_MISC].
* math/math-svid-compat.h: New file.
* conform/linknamespace.pl (@whitelist): Remove matherr, matherrf
and matherrl.
* include/math.h [!_ISOMAC] (__matherr): Remove.
* manual/arith.texi (FP Exceptions): Do not document matherr.
* math/Makefile (tests): Change test-matherr to test-matherr-3.
(tests-internal): New variable.
(install-lib): Do not add libieee.a.
(non-lib.a): Likewise.
(extra-objs): Do not add libieee.a and ieee-math.o.
(CPPFLAGS-s_lib_version.c): Remove variable.
($(objpfx)libieee.a): Remove rule.
($(addprefix $(objpfx), $(tests-internal)): Depend on $(libm).
* math/ieee-math.c: Remove.
* math/libm-test-support.c (matherr): Remove.
* math/test-matherr.c: Use <support/test-driver.c>. Add copyright
and license notices. Include <math-svid-compat.h> and
<shlib-compat.h>.
(matherr): Undefine as macro. Use compat_symbol_reference.
(_LIB_VERSION): Likewise.
* math/test-matherr-2.c: New file.
* math/test-matherr-3.c: Likewise.
* sysdeps/generic/math_private.h (__kernel_standard): Remove
declaration.
(__kernel_standard_f): Likewise.
(__kernel_standard_l): Likewise.
* sysdeps/ieee754/s_lib_version.c: Do not include <math.h> or
<math_private.h>. Include <math-svid-compat.h>.
(_LIB_VERSION): Undefine as macro.
(_LIB_VERSION_INTERNAL): Always initialize to _POSIX_. Define
only if [LIBM_SVID_COMPAT || !defined SHARED]. If
[LIBM_SVID_COMPAT], use compat_symbol.
* sysdeps/ieee754/s_matherr.c: Do not include <math.h> or
<math_private.h>. Include <math-svid-compat.h>.
(matherr): Undefine as macro.
(__matherr): Define only if [LIBM_SVID_COMPAT]. Use
compat_symbol.
* sysdeps/ia64/fpu/libm_error.c: Include <math-svid-compat.h>.
[_LIBC && LIBM_SVID_COMPAT] (matherrf): Use
compat_symbol_reference.
[_LIBC && LIBM_SVID_COMPAT] (matherrl): Likewise.
[_LIBC && !LIBM_SVID_COMPAT] (matherrf): Define as macro.
[_LIBC && !LIBM_SVID_COMPAT] (matherrl): Likewise.
* sysdeps/ia64/fpu/libm_support.h: Include <math-svid-compat.h>.
(MATHERR_D): Remove declaration.
[!_LIBC] (_LIB_VERSION_TYPE): Likewise
[!LIBM_BUILD] (_LIB_VERSIONIMF): Likewise.
[LIBM_BUILD] (pmatherrf): Likewise.
[LIBM_BUILD] (pmatherr): Likewise.
[LIBM_BUILD] (pmatherrl): Likewise.
(DOMAIN): Likewise.
(SING): Likewise.
(OVERFLOW): Likewise.
(UNDERFLOW): Likewise.
(TLOSS): Likewise.
(PLOSS): Likewise.
* sysdeps/ia64/fpu/s_matherrf.c: Include <math-svid-compat.h>.
(__matherrf): Define only if [LIBM_SVID_COMPAT]. Use
compat_symbol.
* sysdeps/ia64/fpu/s_matherrl.c: Include <math-svid-compat.h>.
(__matherrl): Define only if [LIBM_SVID_COMPAT]. Use
compat_symbol.
* math/lgamma-compat.h: Include <math-svid-compat.h>.
* math/w_acos_compat.c: Likewise.
* math/w_acosf_compat.c: Likewise.
* math/w_acosh_compat.c: Likewise.
* math/w_acoshf_compat.c: Likewise.
* math/w_acoshl_compat.c: Likewise.
* math/w_acosl_compat.c: Likewise.
* math/w_asin_compat.c: Likewise.
* math/w_asinf_compat.c: Likewise.
* math/w_asinl_compat.c: Likewise.
* math/w_atan2_compat.c: Likewise.
* math/w_atan2f_compat.c: Likewise.
* math/w_atan2l_compat.c: Likewise.
* math/w_atanh_compat.c: Likewise.
* math/w_atanhf_compat.c: Likewise.
* math/w_atanhl_compat.c: Likewise.
* math/w_cosh_compat.c: Likewise.
* math/w_coshf_compat.c: Likewise.
* math/w_coshl_compat.c: Likewise.
* math/w_exp10_compat.c: Likewise.
* math/w_exp10f_compat.c: Likewise.
* math/w_exp10l_compat.c: Likewise.
* math/w_exp2_compat.c: Likewise.
* math/w_exp2f_compat.c: Likewise.
* math/w_exp2l_compat.c: Likewise.
* math/w_fmod_compat.c: Likewise.
* math/w_fmodf_compat.c: Likewise.
* math/w_fmodl_compat.c: Likewise.
* math/w_hypot_compat.c: Likewise.
* math/w_hypotf_compat.c: Likewise.
* math/w_hypotl_compat.c: Likewise.
* math/w_j0_compat.c: Likewise.
* math/w_j0f_compat.c: Likewise.
* math/w_j0l_compat.c: Likewise.
* math/w_j1_compat.c: Likewise.
* math/w_j1f_compat.c: Likewise.
* math/w_j1l_compat.c: Likewise.
* math/w_jn_compat.c: Likewise.
* math/w_jnf_compat.c: Likewise.
* math/w_jnl_compat.c: Likewise.
* math/w_lgamma_main.c: Likewise.
* math/w_lgamma_r_compat.c: Likewise.
* math/w_lgammaf_main.c: Likewise.
* math/w_lgammaf_r_compat.c: Likewise.
* math/w_lgammal_main.c: Likewise.
* math/w_lgammal_r_compat.c: Likewise.
* math/w_log10_compat.c: Likewise.
* math/w_log10f_compat.c: Likewise.
* math/w_log10l_compat.c: Likewise.
* math/w_log2_compat.c: Likewise.
* math/w_log2f_compat.c: Likewise.
* math/w_log2l_compat.c: Likewise.
* math/w_log_compat.c: Likewise.
* math/w_logf_compat.c: Likewise.
* math/w_logl_compat.c: Likewise.
* math/w_pow_compat.c: Likewise.
* math/w_powf_compat.c: Likewise.
* math/w_powl_compat.c: Likewise.
* math/w_remainder_compat.c: Likewise.
* math/w_remainderf_compat.c: Likewise.
* math/w_remainderl_compat.c: Likewise.
* math/w_scalb_compat.c: Likewise.
* math/w_scalbf_compat.c: Likewise.
* math/w_scalbl_compat.c: Likewise.
* math/w_sinh_compat.c: Likewise.
* math/w_sinhf_compat.c: Likewise.
* math/w_sinhl_compat.c: Likewise.
* math/w_sqrt_compat.c: Likewise.
* math/w_sqrtf_compat.c: Likewise.
* math/w_sqrtl_compat.c: Likewise.
* math/w_tgamma_compat.c: Likewise.
* math/w_tgammaf_compat.c: Likewise.
* math/w_tgammal_compat.c: Likewise.
* sysdeps/ieee754/dbl-64/w_exp_compat.c: Likewise.
* sysdeps/ieee754/flt-32/w_expf_compat.c: Likewise.
* sysdeps/ieee754/k_standard.c: Likewise.
* sysdeps/ieee754/k_standardf.c: Likewise.
* sysdeps/ieee754/k_standardl.c: Likewise.
* sysdeps/ieee754/ldbl-128/w_expl_compat.c: Likewise.
* sysdeps/ieee754/ldbl-128ibm/w_expl_compat.c: Likewise.
* sysdeps/ieee754/ldbl-96/w_expl_compat.c: Likewise.
* sysdeps/powerpc/powerpc32/power4/fpu/w_sqrt_compat.S: Likewise.
* sysdeps/powerpc/powerpc32/power4/fpu/w_sqrtf_compat.S: Likewise.
* sysdeps/powerpc/powerpc32/power5/fpu/w_sqrt_compat.S: Likewise.
* sysdeps/powerpc/powerpc32/power5/fpu/w_sqrtf_compat.S: Likewise.
* sysdeps/sparc/sparc32/fpu/w_sqrt_compat.S: Likewise.
* sysdeps/sparc/sparc32/fpu/w_sqrtf_compat.S: Likewise.
* sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/w_sqrt_compat-vis3.S:
Likewise.
* sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/w_sqrtf_compat-vis3.S:
Likewise.
* sysdeps/sparc/sparc32/sparcv9/fpu/w_sqrt_compat.S: Likewise.
* sysdeps/sparc/sparc32/sparcv9/fpu/w_sqrtf_compat.S: Likewise.
* sysdeps/sparc/sparc64/fpu/w_sqrt_compat.S: Likewise.
* sysdeps/sparc/sparc64/fpu/w_sqrtf_compat.S: Likewise.
Remove enum __ptrace_flags along with the only constant it contains,
PTRACE_SEIZE_DEVEL, from Linux's sys/ptrace.h files.
This temporary development constant shouldn't have been added to
sys/ptrace.h in the first place. It was introduced in Linux by commit
v3.1-rc1~308^2~28 as a temporary part of new experimental PTRACE_SEIZE
interface. Later, as PTRACE_SEIZE stabilized and lost its experimental
status, this flag was removed from Linux by commit v3.4-rc1~109^2~20.
* sysdeps/unix/sysv/linux/sys/ptrace.h (enum __ptrace_flags,
PTRACE_SEIZE_DEVEL): Remove.
* sysdeps/unix/sysv/linux/aarch64/sys/ptrace.h: Likewise.
* sysdeps/unix/sysv/linux/ia64/sys/ptrace.h: Likewise.
* sysdeps/unix/sysv/linux/powerpc/sys/ptrace.h: Likewise.
* sysdeps/unix/sysv/linux/s390/sys/ptrace.h: Likewise.
* sysdeps/unix/sysv/linux/sparc/sys/ptrace.h: Likewise.