glibc/sysdeps/unix/sysv/linux/arm/kernel-features.h

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/* Set flags signalling availability of kernel features based on given
kernel version number.
Copyright (C) 2006-2018 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library. If not, see
<http://www.gnu.org/licenses/>. */
#include_next <kernel-features.h>
/* The ARM kernel before 3.14.3 may or may not support
Correct robust mutex / PI futex kernel assumptions (bug 9894). This patch continues fixing __ASSUME_* issues in preparation for moving to a 2.6.32 minimum kernel version by addressing assumptions on robust mutex and PI futex support availability. Those assumptions are bug 9894, but to be clear this patch does not address all the issues from that bug about wrong version assumptions, only those still applicable for --enable-kernel=2.6.32 or later (with the expectation that the move to that minimum kernel will obsolete the other parts of the bug). The patch is independent of <https://sourceware.org/ml/libc-alpha/2014-03/msg00585.html>, my other pending-review patch preparing for the kernel version change; the two together complete all the changes I believe are needed in preparation regarding any macro in sysdeps/unix/sysv/linux/kernel-features.h that would be affected by such a change. (I have not checked the correctness of macros whose conditions are unaffected by such a change, or macros only defined in other kernel-features.h files.) As discussed in that bug, robust mutexes and PI futexes need futex_atomic_cmpxchg_inatomic to be implemented, in addition to certain syscalls needed for robust mutexes (and architecture-independent kernel pieces for all the features in question). That is, as I understand it, they need futex_atomic_cmpxchg_inatomic to *work* (not return an ENOSYS error). The issues identified in my analysis relate to ARM, M68K, MicroBlaze, MIPS and SPARC. On ARM, whether futex_atomic_cmpxchg_inatomic works depends on the kernel configuration. As of 3.13, the condition for *not* working is CONFIG_CPU_USE_DOMAINS && CONFIG_SMP. As of 2.6.32 it was simply CONFIG_SMP that meant the feature was not implemented. I don't know if there are any circumstances in which we can say "we can assume a userspace glibc binary built with these options will never run on a kernel with the problematic configuration", but at least for now I'm just undefining the relevant __ASSUME_* macros for ARM. On M68K, two of the three macros are undefined for kernels before 3.10, but as far as I can see __ASSUME_FUTEX_LOCK_PI is in the same group needing futex_atomic_cmpxchg_inatomic support and so should be undefined as well. On MicroBlaze the required support was added in 2.6.33. On MIPS, the support depends on cpu_has_llsc in the kernel - that is, actual hardware LL/SC support (GCC and glibc for MIPS GNU/Linux rely on the instructions being supported in some way, but it may be kernel emulation; futex_atomic_cmpxchg_inatomic doesn't work with that emulation). The same condition as in GCC for indicating LL/SC support may not be available is used for undefining the macros in glibc, __mips == 1 || defined _MIPS_ARCH_R5900. (Maybe we could in fact desupport MIPS processors without the hardware support in glibc.) On SPARC, 32-bit kernels don't support futex_atomic_cmpxchg_inatomic; __arch64__ || __sparc_v9__ is used as the condition for binaries that won't run on 32-bit kernels. This patch is not tested beyond the sanity check of an x86_64 build. [BZ #9894] * sysdeps/unix/sysv/linux/kernel-features.h [__sparc__ && !__arch64__ && !__sparc_v9__] (__ASSUME_SET_ROBUST_LIST): Do not define. [__sparc__ && !__arch64__ && !__sparc_v9__] (__ASSUME_FUTEX_LOCK_PI): Likewise. [__sparc__ && !__arch64__ && !__sparc_v9__] (__ASSUME_REQUEUE_PI): Likewise. * sysdeps/unix/sysv/linux/arm/kernel-features.h (__ASSUME_FUTEX_LOCK_PI): Undefine. (__ASSUME_REQUEUE_PI): Likewise. (__ASSUME_SET_ROBUST_LIST): Likewise. * sysdeps/unix/sysv/linux/m68k/kernel-features.h [__LINUX_KERNEL_VERSION < 0x030a00] (__ASSUME_FUTEX_LOCK_PI): Undefine. * sysdeps/unix/sysv/linux/microblaze/kernel-features.h [__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_FUTEX_LOCK_PI): Likewise. [__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_REQUEUE_PI): Likewise. [__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_SET_ROBUST_LIST): Likewise. * sysdeps/unix/sysv/linux/mips/kernel-features.h [__mips == 1 || _MIPS_ARCH_R5900] (__ASSUME_FUTEX_LOCK_PI): Undefine. [__mips == 1 || _MIPS_ARCH_R5900] (__ASSUME_REQUEUE_PI): Likewise. [__mips == 1 || _MIPS_ARCH_R5900] (__ASSUME_SET_ROBUST_LIST): Likewise.
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futex_atomic_cmpxchg_inatomic, depending on kernel
configuration. */
#if __LINUX_KERNEL_VERSION < 0x030E03
# undef __ASSUME_SET_ROBUST_LIST
#endif
Consolidate posix_fadvise implementations This patch consolidates mostly of the Linux posix_fadvise{64} implementations on sysdeps/unix/sysv/linux/posix_fadvise{64}.c. It still keeps arch-specific files for: * S390-32: it uses a packed structure to pass all the arguments on syscall. It is the only supported port that implements __NR_fadvise64_64 in this way. * ARM: it does not implement __NR_fadvise64 (as other 32-bits ports), so posix_fadvise calls internal posix_fadvise64 symbol. * MIPS64 n64: it requires a different version number that other ports. The new macro SYSCALL_LL{64} is used to handle the offset argument and INTERNAL_SYSCALL_CALL to handle passing the correct number of expect arguments. The default Linux adds two new defines a port can use to control how __NR_fadvise64_64 passes the kernel arguments: * __ASSUME_FADVISE64_64_6ARG: the 'advise' argument is moved on second position. This is the case of powerpc32 and arm to avoid implement 7 argument syscall. * __ASSUME_FADVISE64_64_NO_ALIGN: for ABIs that defines __ASSUME_ALIGNED_REGISTER_PAIRS packs the offset without the leading '0'. This is the case of tile 32 bits. ARM also defines __NR_fadvise64_64 as __NR_arm_fadvise64_64 (which is also handled on arch kernel-feature.h). Tested on x86_64, x32, i686, armhf, and aarch64. * posix/Makefile (tests): Add tst-posix_fadvise and tst-posix_fadvise64. * posix/tst-posix_fadvise.c: New file. * posix/tst-posix_fadvise64.c: Likewise. * posix/tst-posix_fadvise-common.c: Likewise. * sysdeps/unix/sysv/linux/arm/kernel-features.h (__ASSUME_FADVISE64_64_6ARG): Define. * sysdeps/unix/sysv/linux/powerpc/kernel-features.h [!__powerpc64__] (__ASSUME_FADVISE64_64_6ARG): Add define. * sysdeps/unix/sysv/linux/arm/posix_fadvise64.c: Remove file. * sysdeps/unix/sysv/linux/generic/wordsize-32/posix_fadvise.c: Likewise. * sysdeps/unix/sysv/linux/i386/posix_fadvise64.S: Likewise. * sysdeps/unix/sysv/linux/mips/mips32/posix_fadvise.c: Likewise. * sysdeps/unix/sysv/linux/mips/mips32/posix_fadvise64.c: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n32/posix_fadvise.c: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n32/posix_fadvise64.c: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n64/posix_fadvise.c: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/posix_fadvise.c: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/posix_fadvise64.c: Likewise. * sysdeps/unix/sysv/linux/wordsize-64/posix_fadvise.c: Likewise. * sysdeps/unix/sysv/linux/wordsize-64/posix_fadvise64.c: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n64/posix_fadvise64.c (SHLIB_COMPAT(libc, GLIBC_2_2, GLIBC_2_3_3) [__posix_fadvise64_l64]: Alias to __posix_fadvise64_l32. (SHLIB_COMPAT(libc, GLIBC_2_2, GLIBC_2_3_3) [__posix_fadvise64_l32]: Add compat definition to posix_fadvise64. (SHLIB_COMPAT(libc, GLIBC_2_2, GLIBC_2_3_3) [__posix_fadvise64_l64]: Add versioned definition to posix_fadvise64. * sysdeps/unix/sysv/linux/posix_fadvise.c (posix_fadvise): Build iff __OFF_T_MATCHES_OFF64_T is defined, use INTERNAL_SYSCALL_CALL, add __ASSUME_FADVISE64_64_6ARG/__ASSUME_FADVISE64_64_NO_ALIGN support. * sysdeps/unix/sysv/linux/posix_fadvise64.c (posix_fadvise64): Add __ASSUME_FADVISE64_64_NO_ALIGN support and use INTERNAL_SYSCALL_CALL.
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/* ARM fadvise64_64 reorganize the syscall arguments. */
#define __ASSUME_FADVISE64_64_6ARG 1
/* Define this if your 32-bit syscall API requires 64-bit register
pairs to start with an even-number register. */
#define __ASSUME_ALIGNED_REGISTER_PAIRS 1
Consolidate posix_fadvise implementations This patch consolidates mostly of the Linux posix_fadvise{64} implementations on sysdeps/unix/sysv/linux/posix_fadvise{64}.c. It still keeps arch-specific files for: * S390-32: it uses a packed structure to pass all the arguments on syscall. It is the only supported port that implements __NR_fadvise64_64 in this way. * ARM: it does not implement __NR_fadvise64 (as other 32-bits ports), so posix_fadvise calls internal posix_fadvise64 symbol. * MIPS64 n64: it requires a different version number that other ports. The new macro SYSCALL_LL{64} is used to handle the offset argument and INTERNAL_SYSCALL_CALL to handle passing the correct number of expect arguments. The default Linux adds two new defines a port can use to control how __NR_fadvise64_64 passes the kernel arguments: * __ASSUME_FADVISE64_64_6ARG: the 'advise' argument is moved on second position. This is the case of powerpc32 and arm to avoid implement 7 argument syscall. * __ASSUME_FADVISE64_64_NO_ALIGN: for ABIs that defines __ASSUME_ALIGNED_REGISTER_PAIRS packs the offset without the leading '0'. This is the case of tile 32 bits. ARM also defines __NR_fadvise64_64 as __NR_arm_fadvise64_64 (which is also handled on arch kernel-feature.h). Tested on x86_64, x32, i686, armhf, and aarch64. * posix/Makefile (tests): Add tst-posix_fadvise and tst-posix_fadvise64. * posix/tst-posix_fadvise.c: New file. * posix/tst-posix_fadvise64.c: Likewise. * posix/tst-posix_fadvise-common.c: Likewise. * sysdeps/unix/sysv/linux/arm/kernel-features.h (__ASSUME_FADVISE64_64_6ARG): Define. * sysdeps/unix/sysv/linux/powerpc/kernel-features.h [!__powerpc64__] (__ASSUME_FADVISE64_64_6ARG): Add define. * sysdeps/unix/sysv/linux/arm/posix_fadvise64.c: Remove file. * sysdeps/unix/sysv/linux/generic/wordsize-32/posix_fadvise.c: Likewise. * sysdeps/unix/sysv/linux/i386/posix_fadvise64.S: Likewise. * sysdeps/unix/sysv/linux/mips/mips32/posix_fadvise.c: Likewise. * sysdeps/unix/sysv/linux/mips/mips32/posix_fadvise64.c: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n32/posix_fadvise.c: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n32/posix_fadvise64.c: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n64/posix_fadvise.c: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/posix_fadvise.c: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/posix_fadvise64.c: Likewise. * sysdeps/unix/sysv/linux/wordsize-64/posix_fadvise.c: Likewise. * sysdeps/unix/sysv/linux/wordsize-64/posix_fadvise64.c: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n64/posix_fadvise64.c (SHLIB_COMPAT(libc, GLIBC_2_2, GLIBC_2_3_3) [__posix_fadvise64_l64]: Alias to __posix_fadvise64_l32. (SHLIB_COMPAT(libc, GLIBC_2_2, GLIBC_2_3_3) [__posix_fadvise64_l32]: Add compat definition to posix_fadvise64. (SHLIB_COMPAT(libc, GLIBC_2_2, GLIBC_2_3_3) [__posix_fadvise64_l64]: Add versioned definition to posix_fadvise64. * sysdeps/unix/sysv/linux/posix_fadvise.c (posix_fadvise): Build iff __OFF_T_MATCHES_OFF64_T is defined, use INTERNAL_SYSCALL_CALL, add __ASSUME_FADVISE64_64_6ARG/__ASSUME_FADVISE64_64_NO_ALIGN support. * sysdeps/unix/sysv/linux/posix_fadvise64.c (posix_fadvise64): Add __ASSUME_FADVISE64_64_NO_ALIGN support and use INTERNAL_SYSCALL_CALL.
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/* ARM only has a syscall for fadvise64{_64} and it is defined with a
non-standard name. */
#define __NR_fadvise64_64 __NR_arm_fadvise64_64
Consolidate Linux recv implementation This patch consolidates the recv Linux syscall implementation on sysdeps/unix/sysv/linux/recv.c. The changes are: 1. Remove recv from auto-generation syscalls.list on the architecture that uses __NR_recv. 2. Define __NR_recv for architectures that supports it. It was done instead of defining in default kernel-features.h because current Linux practice for new ports is to implement only __NR_recvfrom [1] and it will require adding new kernel-features for ports that do not require it (aarch64 for instance). 3. Remove __ASSUME_RECVFROM_FOR_RECV_SYSCALL and decide to use __NR_recvfrom for recv generation based on __ASSUME_RECVFROM_SYSCALL. Checked on i686-linux-gnu, x86_64-linux-gnu, x86_64-linux-gnux32, aarch64-linux-gnu, arm-linux-gnueabihf, and powerpc64le-linux-gnu. * sysdeps/unix/sysv/linux/alpha/syscalls.list: Remove recv from auto-generation list. * sysdeps/unix/sysv/linux/arm/syscalls.list: Likewise. * sysdeps/unix/sysv/linux/hppa/syscalls.list: Likewise. * sysdeps/unix/sysv/linux/ia64/syscalls.list: Likewise. * sysdeps/unix/sysv/linux/mips/syscalls.list: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/syscalls.list: Likewise. * sysdeps/unix/sysv/linux/alpha/kernel-features.h (__ASSUME_RECV_SYSCALL): New define. * sysdeps/unix/sysv/linux/arm/kernel-features.h (__ASSUME_RECV_SYSCALL): Likewise. * sysdeps/unix/sysv/linux/hppa/kernel-features.h (__ASSUME_RECV_SYSCALL): Likewise. * sysdeps/unix/sysv/linux/ia64/kernel-features.h (__ASSUME_RECV_SYSCALL): Likewise. * sysdeps/unix/sysv/linux/mips/kernel-features.h (__ASSUME_RECV_SYSCALL): Likewise. * sysdeps/unix/sysv/linux/i386/kernel-features.h (__ASSUME_RECVFROM_FOR_RECV_SYSCALL): Remove define. * sysdeps/unix/sysv/linux/m68k/kernel-features.h (__ASSUME_RECVFROM_FOR_RECV_SYSCALL): Remove define. * sysdeps/unix/sysv/linux/s390/kernel-features.h (__ASSUME_RECVFROM_FOR_RECV_SYSCALL): Remove define. * sysdeps/unix/sysv/linux/generic/recv.c: Remove file. * sysdeps/unix/sysv/linux/mips/mips64/recv.c: Likewise. * sysdeps/unix/sysv/linux/x86_64/recv.c: Likewise. * sysdeps/unix/sysv/linux/recv.c: Simplify includes. (__libc_recv): Use __ASSUME_RECVFROM_SYSCALL instead of __ASSUME_RECVFROM_FOR_RECV_SYSCALL to issue recvfrom syscall. [1] include/asm-generic/unistd.h (__ARCH_WANT_SYSCALL_DEPRECATED)
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#define __ASSUME_RECV_SYSCALL 1
Consolidate Linux send implementation This patch consolidates the send Linux syscall implementation on sysdeps/unix/sysv/linux/send{to}.c. The changes are: 1. Remove send from auto-generation syscalls.list on the architecture that uses __NR_send. 2. Define __NR_send for architectures that supports it. It was done instead of defining in default kernel-features.h because current Linux practice for new ports are to implement only __NR_sendto [1] and it will require adding new kernel-features for ports that do not require it (aarch64 for instance). 3. Remove __ASSUME_SENDTO_FOR_SEND_SYSCALL and decide to use __NR_sendto for send generation based on __ASSUME_SENDTO_SYSCALL. Checked on i686-linux-gnu, x86_64-linux-gnu, x86_64-linux-gnux32, aarch64-linux-gnu, arm-linux-gnueabihf, and powerpc64le-linux-gnu. * sysdeps/unix/sysv/linux/sysdep.h (HAVE_INTERNAL_SEND_SYMBOL): Define. * sysdeps/unix/sysv/linux/aarch64/sysdep.h (HAVE_INTERNAL_SEND_SYMBOL): Undefine. * sysdeps/unix/sysv/linux/nios2/sysdep.h (HAVE_INTERNAL_SEND_SYMBOL): Likewise. * sysdeps/unix/sysv/linux/tile/sysdep.h (HAVE_INTERNAL_SEND_SYMBOL): Likewise. * sysdeps/unix/sysv/linux/alpha/kernel-features.h (__ASSUME_RECV_SYSCALL): Define. * sysdeps/unix/sysv/linux/arm/kernel-features.h (__ASSUME_RECV_SYSCALL): Likewise. * sysdeps/unix/sysv/linux/hppa/kernel-features.h (__ASSUME_RECV_SYSCALL): Likewise. * sysdeps/unix/sysv/linux/ia64/kernel-features.h (__ASSUME_RECV_SYSCALL): Likewise. * sysdeps/unix/sysv/linux/mips/kernel-features.h (__ASSUME_RECV_SYSCALL): Likewise. * sysdeps/unix/sysv/linux/i386/kernel-features.h (__ASSUME_SENDTO_FOR_SEND_SYSCALL): Remove define. * sysdeps/unix/sysv/linux/m68k/kernel-features.h (__ASSUME_SENDTO_FOR_SEND_SYSCALL): Likewise. * sysdeps/unix/sysv/linux/s390/kernel-features.h (__ASSUME_SENDTO_FOR_SEND_SYSCALL): Likewise. * sysdeps/unix/sysv/linux/alpha/syscalls.list: Remove send from auto-generation list. * sysdeps/unix/sysv/linux/arm/syscalls.list: Likewise. * sysdeps/unix/sysv/linux/hppa/syscalls.list: Likewise. * sysdeps/unix/sysv/linux/ia64/syscalls.list: Likewike. * sysdeps/unix/sysv/linux/mips/syscalls.list: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/syscalls.list: Likewise. * sysdeps/unix/sysv/linux/send.c: Simplify includes. (__ASSUME_SENDTO_FOR_SEND_SYSCALL): Replace by __ASSUME_SENDTO_SYSCALL. * sysdeps/unix/sysv/linux/x86_64/send.c: Remove file. * sysdeps/unix/sysv/linux/mips/mips64/send.c: Likewise. * sysdeps/unix/sysv/linux/generic/send.c: Likewise.
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#define __ASSUME_SEND_SYSCALL 1
Refactor Linux ARCH_FORK implementation This patch refactors the ARCH_FORK macro and the required architecture specific header to simplify the required architecture definitions to provide the fork syscall semantic and proper document current Linux clone ABI variant. Instead of require the reimplementation of arch-fork.h header, this patch changes the ARCH_FORK to an inline function with clone ABI defined by kernel-features.h define. The generic kernel ABI meant for newer ports is used as default and redefine if the architecture requires. Checked on x86_64-linux-gnu and i686-linux-gnu. Also with a build for all the afected ABIs. * sysdeps/nptl/fork.c (ARCH_FORK): Replace by auch_fork. * sysdeps/unix/sysv/linux/alpha/arch-fork.h: Remove file. * sysdeps/unix/sysv/linux/riscv/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/aarch64/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/arm/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/hppa/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/i386/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/ia64/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/m68k/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/microblaze/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/mips/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/nios2/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/powerpc/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/s390/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/sh/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/sparc/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/tile/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/x86_64/arch-fork.h: Likewise. * sysdeps/unix/sysv/linux/arch-fork.h (arch_fork): New function. * sysdeps/unix/sysv/linux/aarch64/kernel-features.h: New file. * sysdeps/unix/sysv/linux/riscv/kernel-features.h: Likewise. * sysdeps/unix/sysv/linux/arm/kernel-features.h (__ASSUME_CLONE_BACKWARDS): Define. * sysdeps/unix/sysv/linux/createthread.c (ARCH_CLONE): Define to __clone2 if __NR_clone2 is defined. * sysdeps/unix/sysv/linux/hppa/kernel-features.h (__ASSUME_CLONE_BACKWARDS): Likewise. * sysdeps/unix/sysv/linux/i386/kernel-features.h (__ASSUME_CLONE_BACKWARDS): Likewise. * sysdeps/unix/sysv/linux/ia64/kernel-features.h (__ASSUME_CLONE2): Likewise. * sysdeps/unix/sysv/linux/microblaze/kernel-features.h (__ASSUME_CLONE_BACKWARDS3): Likewise. * sysdeps/unix/sysv/linux/kernel-features.h: Document possible clone variants and the define architecture can use. (__ASSUME_CLONE_DEFAULT): Define as default. * sysdeps/unix/sysv/linux/mips/kernel-features.h (__ASSUME_CLONE_BACKWARDS): Likewise. * sysdeps/unix/sysv/linux/powerpc/kernel-features.h (__ASSUME_CLONE_BACKWARDS): Likewise. * sysdeps/unix/sysv/linux/s390/kernel-features.h (__ASSUME_CLONE_BACKWARDS2): Likewise.
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#undef __ASSUME_CLONE_DEFAULT
#define __ASSUME_CLONE_BACKWARDS 1