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Joseph Myers 4f3647e46e Prefer new libm function wrappers for !LIBM_SVID_COMPAT.
The initial obsoletion of SVID libm error handling left the old
wrappers and __kernel_standard still being used for new ports and
static linking, just with macro definitions of _LIB_VERSION and
matherr that meant symbols with those names were never actually used
and the code for different error handling variants could be optimized
out.

This patch cleans things up further by eliminating the
__kernel_standard use for new ports and static linking.  Now, the old
wrappers no longer generate any code in the !LIBM_SVID_COMPAT case,
while the new errno-only wrappers that were added for float128 support
are now also used for float, double and long double in that case.

The changes are generally straightforward.  The w_scalb*_compat
wrappers continue to be used (scalb is obsolescent in the sense of not
being supported for float128, but is present in supported standards -
the 2001 edition of POSIX and earlier XSI versions - so remains
supported for static linking and new ports, as do the float and long
double variants that are existing GNU extensions).  Those wrappers
would only call __kernel_standard in the _LIB_VERSION == _SVID_ case.
Since we would like to be able to compile most of glibc without
optimization, relying on a static function whose only use is under an
if (0) condition being optimized away to avoid an undefined
__kernel_standard reference may not be a good idea.  Thus, the
relevant code in the scalb wrappers has LIBM_SVID_COMPAT conditionals
added to guarantee it's not built at all in the case where
__kernel_standard does not exist.

Just as i386 has its own w_sqrt_compat.c, so w_sqrt.c is also added.
ia64 gets dummy w_*.c to prevent those files being built where they
would conflict with the ia64 libm, as with its existing w_*_compat.c.

Conditions disabling code for !LIBM_SVID_COMPAT are needed in both the
math/ wrappers and in the long double wrappers in ldbl-opt (to avoid
them setting up aliases and symbol versions for undefined symbols).  I
hope that future cleanups to how libm function aliases and symbol
versioning are done will eliminate the need for most of the ldbl-opt
wrappers.

Tested for x86_64 and x86, and with build-many-glibcs.py.

	* sysdeps/generic/math-type-macros-double.h: Include
	<math-svid-compat.h>.
	(__USE_WRAPPER_TEMPLATE): Define to !LIBM_SVID_COMPAT.
	* sysdeps/generic/math-type-macros-float.h: Include
	<math-svid-compat.h>.
	(__USE_WRAPPER_TEMPLATE): Define to !LIBM_SVID_COMPAT.
	* sysdeps/generic/math-type-macros-ldouble.h: Include
	<math-svid-compat.h>.
	(__USE_WRAPPER_TEMPLATE): Define to !LIBM_SVID_COMPAT.
	* math/lgamma-compat.h (BUILD_LGAMMA): Include LIBM_SVID_COMPAT
	condition.
	* math/w_acos_compat.c: Condition contents on [LIBM_SVID_COMPAT].
	* 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_r_compat.c: Likewise.
	* math/w_lgammaf_r_compat.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_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.
	* math/w_scalb_compat.c (sysv_scalb): Condition definition on
	[LIBM_SVID_COMPAT].
	(__scalb): Condition call to sysv_scalb on [LIBM_SVID_COMPAT].
	* math/w_scalbf_compat.c (sysv_scalbf): Condition definition on
	[LIBM_SVID_COMPAT].
	(__scalbf): Condition call to sysv_scalbf on [LIBM_SVID_COMPAT].
	* math/w_scalbl_compat.c (sysv_scalbl): Condition definition on
	[LIBM_SVID_COMPAT].
	(__scalbl): Condition call to sysv_scalbl on [LIBM_SVID_COMPAT].
	* sysdeps/i386/fpu/w_sqrt.c: New file.
	* sysdeps/ia64/fpu/w_acos.c: Likewise.
	* sysdeps/ia64/fpu/w_acosf.c: Likewise.
	* sysdeps/ia64/fpu/w_acosh.c: Likewise.
	* sysdeps/ia64/fpu/w_acoshf.c: Likewise.
	* sysdeps/ia64/fpu/w_acoshl.c: Likewise.
	* sysdeps/ia64/fpu/w_acosl.c: Likewise.
	* sysdeps/ia64/fpu/w_asin.c: Likewise.
	* sysdeps/ia64/fpu/w_asinf.c: Likewise.
	* sysdeps/ia64/fpu/w_asinl.c: Likewise.
	* sysdeps/ia64/fpu/w_atan2.c: Likewise.
	* sysdeps/ia64/fpu/w_atan2f.c: Likewise.
	* sysdeps/ia64/fpu/w_atan2l.c: Likewise.
	* sysdeps/ia64/fpu/w_atanh.c: Likewise.
	* sysdeps/ia64/fpu/w_atanhf.c: Likewise.
	* sysdeps/ia64/fpu/w_atanhl.c: Likewise.
	* sysdeps/ia64/fpu/w_cosh.c: Likewise.
	* sysdeps/ia64/fpu/w_coshf.c: Likewise.
	* sysdeps/ia64/fpu/w_coshl.c: Likewise.
	* sysdeps/ia64/fpu/w_exp.c: Likewise.
	* sysdeps/ia64/fpu/w_exp10.c: Likewise.
	* sysdeps/ia64/fpu/w_exp10f.c: Likewise.
	* sysdeps/ia64/fpu/w_exp10l.c: Likewise.
	* sysdeps/ia64/fpu/w_exp2.c: Likewise.
	* sysdeps/ia64/fpu/w_exp2f.c: Likewise.
	* sysdeps/ia64/fpu/w_exp2l.c: Likewise.
	* sysdeps/ia64/fpu/w_expf.c: Likewise.
	* sysdeps/ia64/fpu/w_expl.c: Likewise.
	* sysdeps/ia64/fpu/w_fmod.c: Likewise.
	* sysdeps/ia64/fpu/w_fmodf.c: Likewise.
	* sysdeps/ia64/fpu/w_fmodl.c: Likewise.
	* sysdeps/ia64/fpu/w_hypot.c: Likewise.
	* sysdeps/ia64/fpu/w_hypotf.c: Likewise.
	* sysdeps/ia64/fpu/w_hypotl.c: Likewise.
	* sysdeps/ia64/fpu/w_lgamma_r.c: Likewise.
	* sysdeps/ia64/fpu/w_lgammaf_r.c: Likewise.
	* sysdeps/ia64/fpu/w_lgammal_r.c: Likewise.
	* sysdeps/ia64/fpu/w_log.c: Likewise.
	* sysdeps/ia64/fpu/w_log10.c: Likewise.
	* sysdeps/ia64/fpu/w_log10f.c: Likewise.
	* sysdeps/ia64/fpu/w_log10l.c: Likewise.
	* sysdeps/ia64/fpu/w_log2.c: Likewise.
	* sysdeps/ia64/fpu/w_log2f.c: Likewise.
	* sysdeps/ia64/fpu/w_log2l.c: Likewise.
	* sysdeps/ia64/fpu/w_logf.c: Likewise.
	* sysdeps/ia64/fpu/w_logl.c: Likewise.
	* sysdeps/ia64/fpu/w_pow.c: Likewise.
	* sysdeps/ia64/fpu/w_powf.c: Likewise.
	* sysdeps/ia64/fpu/w_powl.c: Likewise.
	* sysdeps/ia64/fpu/w_remainder.c: Likewise.
	* sysdeps/ia64/fpu/w_remainderf.c: Likewise.
	* sysdeps/ia64/fpu/w_remainderl.c: Likewise.
	* sysdeps/ia64/fpu/w_sinh.c: Likewise.
	* sysdeps/ia64/fpu/w_sinhf.c: Likewise.
	* sysdeps/ia64/fpu/w_sinhl.c: Likewise.
	* sysdeps/ia64/fpu/w_sqrt.c: Likewise.
	* sysdeps/ia64/fpu/w_sqrtf.c: Likewise.
	* sysdeps/ia64/fpu/w_sqrtl.c: Likewise.
	* sysdeps/ia64/fpu/w_tgamma.c: Likewise.
	* sysdeps/ia64/fpu/w_tgammaf.c: Likewise.
	* sysdeps/ia64/fpu/w_tgammal.c: Likewise.
	* sysdeps/ieee754/dbl-64/w_exp_compat.c: Condition contents on
	[LIBM_SVID_COMPAT].
	* 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/ieee754/ldbl-64-128/w_expl_compat.c: Condition
	long_double_symbol call on [LIBM_SVID_COMPAT].
	* sysdeps/ieee754/ldbl-opt/w_acoshl_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_acosl_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_asinl_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_atan2l_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_atanhl_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_coshl_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_fmodl_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_hypotl_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_j0l_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_j1l_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_jnl_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_lgammal_r_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_log10l_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_log2l_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_logl_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_powl_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_remainderl_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_sinhl_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_sqrtl_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_tgammal_compat.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/w_exp10l_compat.c: Condition
	long_double_symbol and compat_symbol calls on [LIBM_SVID_COMPAT].
2017-09-05 23:35:55 +00:00
argp Remove __need macros from errno.h (__need_Emath, __need_error_t). 2017-06-14 08:14:34 -04:00
assert Fix position of tests-unsupported definition in assert/Makefile. 2017-08-22 00:30:51 +00:00
benchtests benchtests: Do not compile benchmark objects as libc modules [BZ #21864] 2017-08-21 19:28:54 +02:00
bits Simplify NAN definitions. 2017-08-31 16:39:25 +00:00
catgets Don't compile non-lib modules as lib modules [BZ #21864] 2017-08-21 05:34:54 -07:00
ChangeLog.old Move all old ChangeLogs to a top-level ChangeLog.old directory. 2017-09-01 09:31:43 -04:00
conform Fix mcontext_t sigcontext namespace (bug 21457). 2017-08-30 22:02:04 +00:00
crypt Add missing header files throughout the testsuite. 2017-02-16 17:33:18 -05:00
csu Remove Roland McGrath/Ulrich Drepper et al. from DSO banner 2017-09-01 10:09:21 -07:00
ctype Use locale_t, not __locale_t, throughout glibc 2017-06-20 20:30:06 -04:00
debug Fix pcprofiledump cross-endian condition (bug 22086). 2017-09-05 15:14:09 +00:00
dev Rename xlocale.h to bits/types/__locale_t.h. 2017-06-20 20:28:11 -04:00
dirent dirent: Remove internal_function attribute 2017-08-31 16:02:40 +02:00
dlfcn dlfcn: Remove internal_function attribute 2017-08-31 16:12:03 +02:00
elf elf: Remove internal_function attribute 2017-08-31 16:59:37 +02:00
gmon gmon: Remove internal_function attribute 2017-08-31 16:16:07 +02:00
gnulib Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
grp Mark internal nss symbols with attribute_hidden [BZ #18822] 2017-08-21 05:31:19 -07:00
gshadow Remove __need macros from stdio.h and wchar.h. 2017-06-08 13:58:17 -04:00
hesiod Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
hurd hurd: Remove duplicate symbol version 2017-08-28 14:19:55 +02:00
iconv iconv, intl, locale, wcsmbs: Remove internal_function 2017-08-31 15:59:06 +02:00
iconvdata Increase some test timeouts. 2017-07-06 17:01:03 +00:00
include Fix tests that are testing obsoleted functionality 2017-09-05 12:24:00 -07:00
inet inet: Remove internal_function attribute 2017-08-31 18:52:00 +02:00
intl iconv, intl, locale, wcsmbs: Remove internal_function 2017-08-31 15:59:06 +02:00
io Hide __chmod and __mkdir [BZ #18822] 2017-09-04 13:38:51 -07:00
libidn Move all old ChangeLogs to a top-level ChangeLog.old directory. 2017-09-01 09:31:43 -04:00
libio libio: Assume _LIBC, weak_alias, errno, (__set_)errno &c are defined 2017-08-31 14:48:25 +02:00
locale Add miq_NI locale for Miskito 2017-09-05 15:04:23 +02:00
localedata Add miq_NI locale for Miskito 2017-09-05 15:04:23 +02:00
login Consolidate remaning non cancellable definitions 2017-08-23 10:47:03 -03:00
mach hurd: Remove duplicate symbol version 2017-08-28 14:19:55 +02:00
malloc Fix tests that are testing obsoleted functionality 2017-09-05 12:24:00 -07:00
manual Obsolete pow10 functions. 2017-09-01 21:13:18 +00:00
math Prefer new libm function wrappers for !LIBM_SVID_COMPAT. 2017-09-05 23:35:55 +00:00
mathvec Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
misc hurd: Fix build ot misc/tst-preadvwritev2-common.c 2017-09-03 17:51:15 +02:00
nis Consistently use uintN_t not u_intN_t everywhere. 2017-08-07 19:55:34 +00:00
nptl Remove Roland McGrath/Ulrich Drepper et al. from DSO banner 2017-09-01 10:09:21 -07:00
nptl_db Move all old ChangeLogs to a top-level ChangeLog.old directory. 2017-09-01 09:31:43 -04:00
nscd NSS: Remove internal_function function attribute 2017-08-31 15:59:06 +02:00
nss getaddrinfo: Fix error handling in gethosts [BZ #21915] [BZ #21922] 2017-09-01 09:34:29 +02:00
po Fix spelling mistake in fr.po 2017-08-14 09:30:54 +02:00
posix Update tst-regex.c/tst-regex2.c for old ChangeLog move 2017-09-01 10:20:49 -07:00
pwd Remove __need macros from stdio.h and wchar.h. 2017-06-08 13:58:17 -04:00
resolv hurd: fix resolv/tst-resolv-res_init-skeleton.c build 2017-09-03 19:44:07 +02:00
resource Define struct rusage in sys/wait.h when required (bug 21575). 2017-06-19 11:59:19 +00:00
rt aio: Remove internal_function function attribute 2017-08-31 15:59:06 +02:00
scripts Use Linux 4.13 in build-many-glibcs.py. 2017-09-04 15:34:58 +00:00
setjmp Remove __need macros from signal.h. 2017-05-20 19:04:43 -04:00
shadow Remove __need macros from stdio.h and wchar.h. 2017-06-08 13:58:17 -04:00
signal Fix sigval namespace (bug 21944). 2017-08-16 20:33:59 +00:00
socket __opensock: Remove internal_function attribute 2017-08-17 10:18:15 +02:00
soft-fp Narrowing the visibility of libc-internal.h even further. 2017-03-01 20:33:46 -05:00
stdio-common linux: Implement tmpfile with O_TMPFILE (BZ#21530) 2017-09-01 09:52:47 -03:00
stdlib 2017-09-01 Paul Pluzhnikov <ppluzhnikov@google.com> 2017-09-01 11:35:55 -07:00
streams Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
string string/stratcliff.c: Replace int with size_t [BZ #21982] 2017-08-23 08:23:02 -07:00
sunrpc sunrpc: Remove internal_function attribute 2017-08-31 15:59:02 +02:00
support support_chroot_create: Add support for /etc/hosts, /etc/host.conf 2017-09-01 08:58:07 +02:00
sysdeps Prefer new libm function wrappers for !LIBM_SVID_COMPAT. 2017-09-05 23:35:55 +00:00
sysvipc Fix test-sysvsem on some platforms 2017-01-02 18:53:50 -02:00
termios Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
time time: Remove the internal_function attribute 2017-08-31 15:59:07 +02:00
timezone zic: Use PRIdMAX to print line numbers 2017-07-25 12:34:14 +05:30
wcsmbs iconv, intl, locale, wcsmbs: Remove internal_function 2017-08-31 15:59:06 +02:00
wctype Use locale_t, not __locale_t, throughout glibc 2017-06-20 20:30:06 -04:00
.gitattributes Assume __NR_openat is always defined 2016-03-23 23:35:08 +01:00
.gitignore Add *.pyc to .gitignore 2015-05-18 15:26:26 +05:30
abi-tags Remove the bulk of the NaCl port. 2017-05-20 08:09:10 -04:00
aclocal.m4 gmon: Add test for basic mcount/gprof functionality 2017-08-15 15:49:45 +02:00
ChangeLog Prefer new libm function wrappers for !LIBM_SVID_COMPAT. 2017-09-05 23:35:55 +00:00
config.h.in i386: Do not set internal_function 2017-08-14 15:08:48 +02:00
config.make.in gmon: Add test for basic mcount/gprof functionality 2017-08-15 15:49:45 +02:00
configure gmon: Add test for basic mcount/gprof functionality 2017-08-15 15:49:45 +02:00
configure.ac Check linker support for INSERT in linker script 2017-08-04 12:17:30 -07:00
COPYING Update to latest versions of GPL-2.0 and LGPL-2.1 2013-09-09 12:52:48 +10:00
COPYING.LIB Update to latest versions of GPL-2.0 and LGPL-2.1 2013-09-09 12:52:48 +10:00
extra-lib.mk Rename cppflags-iterator.mk to libof-iterator.mk, remove extra-modules.mk. 2017-05-09 07:06:29 -04:00
gen-locales.mk Split locale generation snippet into a separate file 2015-05-13 13:05:28 +05:30
INSTALL Update contributors and latest gcc and binutils versions 2017-08-02 18:22:58 +05:30
libc-abis
libof-iterator.mk Rename cppflags-iterator.mk to libof-iterator.mk, remove extra-modules.mk. 2017-05-09 07:06:29 -04:00
LICENSES Expand LICENSES file. 2012-12-05 21:56:15 +00:00
MAINTAINERS Add MAINTAINERS 2017-05-11 13:38:30 -04:00
Makeconfig Support mcount/gprof test with GCC defaulting to PIE 2017-08-17 04:56:01 -07:00
Makefile Suppress internal declarations for most of the testsuite. 2017-05-11 19:27:59 -04:00
Makefile.in New make target to only build benchmark binaries 2016-04-20 10:23:28 +05:30
Makerules Place $(elf-objpfx)sofini.os last [BZ #22051] 2017-08-31 06:28:46 -07:00
NEWS Obsolete pow10 functions. 2017-09-01 21:13:18 +00:00
o-iterator.mk
README Require Linux kernel 3.2 or later on x86 / x86_64. 2017-05-08 10:45:20 +00:00
Rules Suppress internal declarations for most of the testsuite. 2017-05-11 19:27:59 -04:00
shlib-versions Extend NSS test suite 2017-07-17 15:52:44 -04:00
test-skeleton.c Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
version.h Open master for development 2017-08-02 19:23:16 +05:30

This directory contains the sources of the GNU C Library.
See the file "version.h" for what release version you have.

The GNU C Library is the standard system C library for all GNU systems,
and is an important part of what makes up a GNU system.  It provides the
system API for all programs written in C and C-compatible languages such
as C++ and Objective C; the runtime facilities of other programming
languages use the C library to access the underlying operating system.

In GNU/Linux systems, the C library works with the Linux kernel to
implement the operating system behavior seen by user applications.
In GNU/Hurd systems, it works with a microkernel and Hurd servers.

The GNU C Library implements much of the POSIX.1 functionality in the
GNU/Hurd system, using configurations i[4567]86-*-gnu.  The current
GNU/Hurd support requires out-of-tree patches that will eventually be
incorporated into an official GNU C Library release.

When working with Linux kernels, this version of the GNU C Library
requires Linux kernel version 3.2 or later.

Also note that the shared version of the libgcc_s library must be
installed for the pthread library to work correctly.

The GNU C Library supports these configurations for using Linux kernels:

	aarch64*-*-linux-gnu
	alpha*-*-linux-gnu
	arm-*-linux-gnueabi
	hppa-*-linux-gnu	Not currently functional without patches.
	i[4567]86-*-linux-gnu
	x86_64-*-linux-gnu	Can build either x86_64 or x32
	ia64-*-linux-gnu
	m68k-*-linux-gnu
	microblaze*-*-linux-gnu
	mips-*-linux-gnu
	mips64-*-linux-gnu
	powerpc-*-linux-gnu	Hardware or software floating point, BE only.
	powerpc64*-*-linux-gnu	Big-endian and little-endian.
	s390-*-linux-gnu
	s390x-*-linux-gnu
	sh[34]-*-linux-gnu
	sparc*-*-linux-gnu
	sparc64*-*-linux-gnu
	tilegx-*-linux-gnu
	tilepro-*-linux-gnu

If you are interested in doing a port, please contact the glibc
maintainers; see http://www.gnu.org/software/libc/ for more
information.

See the file INSTALL to find out how to configure, build, and install
the GNU C Library.  You might also consider reading the WWW pages for
the C library at http://www.gnu.org/software/libc/.

The GNU C Library is (almost) completely documented by the Texinfo manual
found in the `manual/' subdirectory.  The manual is still being updated
and contains some known errors and omissions; we regret that we do not
have the resources to work on the manual as much as we would like.  For
corrections to the manual, please file a bug in the `manual' component,
following the bug-reporting instructions below.  Please be sure to check
the manual in the current development sources to see if your problem has
already been corrected.

Please see http://www.gnu.org/software/libc/bugs.html for bug reporting
information.  We are now using the Bugzilla system to track all bug reports.
This web page gives detailed information on how to report bugs properly.

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