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5e7698c6f1
glibc/sysdeps
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Joseph Myers 5e7698c6f1 Reduce kernel-features.h duplication. 
This patch reduces duplication between different architectures'
kernel-features.h files by making the architecture-independent file
define various macros unconditionally (instead of only for a
particular list of architectures), with the architecture-specific
files then undefining the macros if necessary.

Specifically, __ASSUME_O_CLOEXEC (O_CLOEXEC flag to open) and
__ASSUME_SOCK_CLOEXEC (SOCK_NONBLOCK and SOCK_CLOEXEC flags to socket)
are supported on all architectures as of 2.6.32 or the minimum kernel
version for the architecture if later.  For __ASSUME_IN_NONBLOCK,
__ASSUME_PIPE2, __ASSUME_EVENTFD2, __ASSUME_SIGNALFD4 and
__ASSUME_DUP3, the relevant syscalls were added for alpha in 2.6.33
but otherwise the features are available as of 2.6.32.  For
__ASSUME_UTIMES, support is everywhere in 2.6.32 except for
asm-generic architectures and hppa.

Although those were the main cases of duplication among
kernel-features.h files, some other cases of unnecessary definitions
were also cleaned up: the hppa file defined various macros that were
either no longer used at all, or defined by the main file by default
anyway, the ia64 file had duplicative definitions of __ASSUME_PSELECT
and __ASSUME_PPOLL, while mips had such a definition of
__ASSUME_IPC64.

Really, rather than being defined in the main file then undefined for
asm-generic architectures, __ASSUME_UTIMES should become an
hppa-specific macro.  Given that __ASSUME_ATFCTS and
__ASSUME_UTIMENSAT are now always true, the only live __ASSUME_UTIMES
conditional is in sysdeps/unix/sysv/linux/utimes.c, which is not used
for asm-generic architectures.  I think the desired state would be an
hppa-specific file (that includes sysdeps/unix/sysv/linux/utimes.c if
__ASSUME_UTIMES, and otherwise has fallback code), with the fallback
code being removed from the main utimes.c.  But I think that's most
reasonably a separate cleanup once __ASSUME_ATFCTS and
__ASSUME_UTIMESAT have both had conditional code cleaned up.

Given this patch, I think it's straightforward to move non-ex-ports
architectures to having their own kernel-features.h files, like
ex-ports architectures, rather than conditionals in the main file
(i.e., such a move won't require the architecture-specific file to
contain anything that isn't genuinely architecture-specific), and
would encourage architecture maintainers to do so.

Tested x86_64 that the installed shared libraries are unchanged by
this patch.  Note that on some architectures this *will* cause
__ASSUME_* macros to be defined in cases where they weren't previously
but should have been (but this is just optimization, not a fix to a
user-visible bug, so doesn't need a bug report in Bugzilla).

	* sysdeps/unix/sysv/linux/kernel-features.h (__ASSUME_UTIMES):
	Define unconditionally.
	(__ASSUME_O_CLOEXEC): Likewise.
	(__ASSUME_SOCK_CLOEXEC): Likewise.
	(__ASSUME_IN_NONBLOCK): Likewise.
	(__ASSUME_PIPE2): Likewise.
	(__ASSUME_EVENTFD2): Likewise.
	(__ASSUME_SIGNALFD4): Likewise.
	(__ASSUME_DUP3): Likewise.
	* sysdeps/unix/sysv/linux/aarch64/kernel-features.h
	(__ASSUME_DUP3): Do not define.
	(__ASSUME_EVENTFD2): Likewise.
	(__ASSUME_IN_NONBLOCK): Likewise.
	(__ASSUME_O_CLOEXEC): Likewise.
	(__ASSUME_PIPE2): Likewise.
	(__ASSUME_SIGNALFD4): Likewise.
	(__ASSUME_SOCK_CLOEXEC): Likewise.
	(__ASSUME_UTIMES): Undefine.
	* sysdeps/unix/sysv/linux/alpha/kernel-features.h
	(__ASSUME_UTIMES): Do not define.
	(__ASSUME_O_CLOEXEC): Likewise.
	(__ASSUME_SOCK_CLOEXEC): Likewise.
	(__ASSUME_IN_NONBLOCK): Undefine if [__LINUX_KERNEL_VERSION <
	0x020621] instead of defining if [__LINUX_KERNEL_VERSION >=
	0x020621].
	(__ASSUME_PIPE2): Likewise.
	(__ASSUME_EVENTFD2): Likewise.
	(__ASSUME_SIGNALFD4): Likewise.
	[__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_DUP3): Undefine.
	* sysdeps/unix/sysv/linux/arm/kernel-features.h (__ASSUME_UTIMES):
	Do not define.
	(__ASSUME_EVENTFD2): Likewise.
	(__ASSUME_SIGNALFD4): Likewise.
	* sysdeps/unix/sysv/linux/hppa/kernel-features.h
	(__ASSUME_32BITUIDS): Likewise.
	(__ASSUME_TRUNCATE64_SYSCALL): Likewise.
	(__ASSUME_IPC64): Likewise.
	(__ASSUME_ST_INO_64_BIT): Likewise.
	(__ASSUME_GETDENTS64_SYSCALL): Likewise.
	[__LINUX_KERNEL_VERSION < 0x030e00] (__ASSUME_UTIMES): Undefine.
	* sysdeps/unix/sysv/linux/ia64/kernel-features.h
	(__ASSUME_UTIMES): Do not define.
	(__ASSUME_PSELECT): Likewise.
	(__ASSUME_PPOLL): Likewise.
	(__ASSUME_O_CLOEXEC): Likewise.
	(__ASSUME_SOCK_CLOEXEC): Likewise.
	(__ASSUME_IN_NONBLOCK): Likewise.
	(__ASSUME_PIPE2): Likewise.
	(__ASSUME_EVENTFD2): Likewise.
	(__ASSUME_SIGNALFD4): Likewise.
	(__ASSUME_DUP3): Likewise.
	* sysdeps/unix/sysv/linux/m68k/kernel-features.h
	(__ASSUME_UTIMES): Likewise.
	(__ASSUME_O_CLOEXEC): Likewise.
	(__ASSUME_SOCK_CLOEXEC): Likewise.
	(__ASSUME_IN_NONBLOCK): Likewise.
	(__ASSUME_PIPE2): Likewise.
	(__ASSUME_EVENTFD2): Likewise.
	(__ASSUME_SIGNALFD4): Likewise.
	(__ASSUME_DUP3): Likewise.
	* sysdeps/unix/sysv/linux/microblaze/kernel-features.h
	(__ASSUME_UTIMES): Likewise.
	(__ASSUME_O_CLOEXEC): Likewise.
	(__ASSUME_SOCK_CLOEXEC): Likewise.
	(__ASSUME_IN_NONBLOCK): Likewise.
	(__ASSUME_PIPE2): Likewise.
	(__ASSUME_EVENTFD2): Likewise.
	(__ASSUME_SIGNALFD4): Likewise.
	(__ASSUME_DUP3): Likewise.
	* sysdeps/unix/sysv/linux/mips/kernel-features.h (__ASSUME_IPC64):
	Likewise.
	(__ASSUME_UTIMES): Likewise.
	(__ASSUME_EVENTFD2): Likewise.
	(__ASSUME_SIGNALFD4): Likewise.
	* sysdeps/unix/sysv/linux/tile/kernel-features.h
	(__ASSUME_O_CLOEXEC): Likewise.
	(__ASSUME_SOCK_CLOEXEC): Likewise.
	(__ASSUME_IN_NONBLOCK): Likewise.
	(__ASSUME_PIPE2): Likewise.
	(__ASSUME_EVENTFD2): Likewise.
	(__ASSUME_SIGNALFD4): Likewise.
	(__ASSUME_DUP3): Likewise.
	(__ASSUME_UTIMES): Undefine.
2014-05-14 00:45:19 +00:00
..
aarch64 Clean up __exit_thread. 2014-05-13 09:49:20 -07:00
alpha Clean up __exit_thread. 2014-05-13 09:49:20 -07:00
arm Clean up ARM old-ABI symbol versioning relics. 2014-05-14 00:41:20 +00:00
generic Clean up __exit_thread. 2014-05-13 09:49:20 -07:00
gnu Silence a missing-noreturn warning for _Unwind_Resume. 2014-05-09 10:06:20 -07:00
hppa Clean up __exit_thread. 2014-05-13 09:49:20 -07:00
i386 Include SSE state in i386 fenv_t (bug 16064). 2014-05-09 16:59:56 +00:00
ia64 Clean up __exit_thread. 2014-05-13 09:49:20 -07:00
ieee754 [BZ #16823] Fix log1pl returning wrong infinity sign 2014-04-29 15:43:36 +02:00
init_array
m68k Clean up __exit_thread. 2014-05-13 09:49:20 -07:00
mach Some configure-related decrufting. 2014-05-08 11:27:14 -07:00
microblaze Clean up __exit_thread. 2014-05-13 09:49:20 -07:00
mips Clean up __exit_thread. 2014-05-13 09:49:20 -07:00
posix Fix parsing of getai result from nscd for IPv6-only request 2014-05-07 14:21:27 +02:00
powerpc PowerPC: strncpy/stpncpy optimization for PPC64/POWER7 2014-05-06 09:54:25 -05:00
pthread
s390 S/390: Port of lock elision to System/z 2014-05-09 16:58:46 +02:00
sh
sparc Fix v9/64-bit strcmp when string ends in multiple zero bytes. 2014-05-01 12:15:06 -07:00
tile Clean up __exit_thread. 2014-05-13 09:49:20 -07:00
unix Reduce kernel-features.h duplication. 2014-05-14 00:45:19 +00:00
wordsize-32
wordsize-64
x86 Include SSE state in i386 fenv_t (bug 16064). 2014-05-09 16:59:56 +00:00
x86_64 Fix -Wundef warning for FEATURE_INDEX_1. 2014-05-03 00:25:21 -04:00