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Joseph Myers 777d75fbc0 Add feature test macro _ISOC2X_SOURCE.
This patch starts preparation for C2X support in glibc headers by
adding a feature test macro _ISOC2X_SOURCE and corresponding
__GLIBC_USE (ISOC2X).  (I chose to use the newer __GLIBC_USE style for
this rather than the older __USE_* macros tested with #ifdef.)  As
with other such macros, C2X features are also enabled by compiling for
a standard newer than C17, or by using _GNU_SOURCE.

This patch does not itself enable anything new in the headers for C2X;
that is to be done in followup patches.  (For example, most of the TS
18661-1 functions should be declared for C2X without any
__STDC_WANT_IEC_60559_BFP_EXT__ being needed, but the ones that
18661-1 adds to Annex F because of their close relation to IEEE 754
formats do still need the WANT macro in C2X.)

Once C2X becomes an actual standard we'll presumably move to using the
actual year in the feature test macro and __GLIBC_USE, with some
period when both macro spellings are accepted, as was done with
_ISOC9X_SOURCE.

Tested for x86_64.

	* include/features.h (_ISOC2X_SOURCE): New feature test macro.
	Undefine and define to 1 if [_GNU_SOURCE].
	(__GLIBC_USE_ISOC2X): New macro.  Undefine and redefine depending
	on [_ISOC2X_SOURCE] and [__STDC_VERSION__ > 201710L].
	(__USE_ISOC11): Also define to 1 if [_ISOC2X_SOURCE].
	(__USE_ISOC99): Likewise.
	(__USE_ISOC95): Likewise.
	* manual/creature.texi (_ISOC2X_SOURCE): Document.
2019-08-13 11:26:00 +00:00
ChangeLog.old Add more bug numbers to historic ChangeLog entries 2019-04-11 09:32:08 +02:00
argp Fix gcc 9 build errors for make xcheck. [BZ #24556] 2019-06-19 12:32:04 +02:00
assert
benchtests benchtests: Add logb{f} benchmark 2019-07-08 17:22:22 -03:00
bits login: Assume that _HAVE_UT_* constants are true 2019-08-13 12:09:32 +02:00
catgets
conform
crypt
csu
ctype
debug
dirent Linux: Move getdents64 to <dirent.h> 2019-07-29 21:02:46 +02:00
dlfcn dlfcn: Avoid one-element flexible array in Dl_serinfo [BZ #24166] 2019-06-19 10:13:50 +02:00
elf elf: Support elf/tst-dlopen-aout in more configurations 2019-08-12 17:59:13 +02:00
gmon
gnulib
grp nss: Turn __nss_database_lookup into a compatibility symbol 2019-05-15 15:07:49 +02:00
gshadow
hesiod
htl
hurd
iconv iconv: Revert steps array reference counting changes 2019-07-31 11:43:59 +02:00
iconvdata
include Add feature test macro _ISOC2X_SOURCE. 2019-08-13 11:26:00 +00:00
inet Add INADDR_ALLSNOOPERS_GROUP from Linux 5.1 to netinet/in.h. 2019-06-03 11:16:02 +00:00
intl
io Add AT_RECURSIVE from Linux 5.2 to fcntl.h. 2019-08-06 21:17:59 +00:00
libio iconv: Revert steps array reference counting changes 2019-07-31 11:43:59 +02:00
locale locale/C-translit.h.in: Cyrillic -> ASCII transliteration [BZ #2872] 2019-07-20 21:49:38 +02:00
localedata Afar locales: Months and days updated from CLDR (bug 21897). 2019-07-17 11:58:21 +02:00
login login: Assume that _HAVE_UT_* constants are true 2019-08-13 12:09:32 +02:00
mach
malloc Add glibc.malloc.mxfast tunable 2019-08-09 14:04:03 -04:00
manual Add feature test macro _ISOC2X_SOURCE. 2019-08-13 11:26:00 +00:00
math
mathvec
misc <sys/cdefs.h>: Inhibit macro expansion for __glibc_has_include 2019-06-14 16:19:14 +02:00
nis nss_nis, nss_nisplus: Remove RES_USE_INET6 handling 2019-05-16 17:23:23 +02:00
nptl nptl: Use uintptr_t for address diagnostic in nptl/tst-pthread-getattr 2019-07-30 10:35:08 +02:00
nptl_db
nscd nss: Turn __nss_database_lookup into a compatibility symbol 2019-05-15 15:07:49 +02:00
nss nss_db: fix endent wrt NULL mappings [BZ #24695] [BZ #24696] 2019-07-10 14:51:18 -04:00
po Update translations. 2019-07-31 23:38:15 -04:00
posix posix: Fix large mmap64 offset for mips64n32 (BZ#24699) 2019-07-10 16:52:50 -03:00
pwd
resolv Fix build warnings in resolv/res_send.c 2019-07-02 14:07:44 +02:00
resource
rt
scripts build-many-glibcs.py: Use Linux 5.2 by default 2019-07-24 10:59:45 +02:00
setjmp
shadow
signal Linux: Add the tgkill function 2019-05-14 22:55:51 +02:00
socket
soft-fp
stdio-common Prepare vfprintf to use __printf_fp/__printf_fphex with float128 arg 2019-06-27 17:51:59 -03:00
stdlib malloc: make malloc fail with requests larger than PTRDIFF_MAX (BZ#23741) 2019-04-18 17:30:06 -03:00
string Fix gcc 9 build errors for make xcheck. [BZ #24556] 2019-06-19 12:32:04 +02:00
sunrpc
support nss_db: fix endent wrt NULL mappings [BZ #24695] [BZ #24696] 2019-07-10 14:51:18 -04:00
sysdeps login: Assume that _HAVE_UT_* constants are true 2019-08-13 12:09:32 +02:00
sysvipc
termios
time Make mktime etc. compatible with __time64_t 2019-04-30 09:02:17 -07:00
timezone
wcsmbs iconv: Revert steps array reference counting changes 2019-07-31 11:43:59 +02:00
wctype
.gitattributes
.gitignore
COPYING
COPYING.LIB
ChangeLog Add feature test macro _ISOC2X_SOURCE. 2019-08-13 11:26:00 +00:00
INSTALL Update install and NEWS for 2.30 release. 2019-08-01 00:22:46 -04:00
LICENSES
MAINTAINERS
Makeconfig test-container: Install with $(sorted-subdirs) [BZ #24794] 2019-07-29 10:31:06 -03:00
Makefile test-container: Install with $(sorted-subdirs) [BZ #24794] 2019-07-29 10:31:06 -03:00
Makefile.in
Makerules
NEWS Add feature test macro _ISOC2X_SOURCE. 2019-08-13 11:26:00 +00:00
README
Rules
abi-tags
aclocal.m4
config.h.in
config.make.in Make --bindir effective 2019-05-14 11:04:33 -03:00
configure
configure.ac
extra-lib.mk
gen-locales.mk
libc-abis
libof-iterator.mk
o-iterator.mk
shlib-versions
test-skeleton.c
version.h Open master for 2.31 development. 2019-08-01 00:41:53 -04:00

README

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