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Joseph Myers 93eb85ceb2 Refactor float_t, double_t information into bits/flt-eval-method.h.
At present, definitions of float_t and double_t are split among many
bits/mathdef.h headers.

For all but three architectures, these types are float and double.
Furthermore, if you assume __FLT_EVAL_METHOD__ to be defined, that
provides a more generic way of determining the correct values of these
typedefs.  Defining these typedefs more generally based on
__FLT_EVAL_METHOD__ was previously proposed by Paul Eggert in
<https://sourceware.org/ml/libc-alpha/2012-02/msg00002.html>.

This patch refactors things in the way I proposed in
<https://sourceware.org/ml/libc-alpha/2016-11/msg00745.html>.  A new
header bits/flt-eval-method.h defines a single macro,
__GLIBC_FLT_EVAL_METHOD, which is then used by math.h to define
float_t and double_t.  The default is based on __FLT_EVAL_METHOD__
(although actually a default to 0 would have the same effect for
current ports, because ports where values other than 0 or 16 are
possible all have their own headers).

To avoid changing the existing semantics in any case, including for
compilers not defining __FLT_EVAL_METHOD__, architecture-specific
files are then added for m68k, s390, x86 which replicate the existing
semantics.  At least with __FLT_EVAL_METHOD__ values possible with
GCC, there should be no change to the choices of float_t and double_t
for any supported configuration.

Architecture maintainer notes:

* m68k: sysdeps/m68k/m680x0/bits/flt-eval-method.h always defines
  __GLIBC_FLT_EVAL_METHOD to 2 to replicate the existing logic.  But
  actually GCC defines __FLT_EVAL_METHOD__ to 0 if TARGET_68040.  It
  might make sense to make the header prefer to base things on
  __FLT_EVAL_METHOD__ if defined, like the x86 version, and so make
  the choices of these types more accurate (with a NEWS entry as for
  the other changes to these types on particular architectures).

* s390: sysdeps/s390/bits/flt-eval-method.h always defines
  __GLIBC_FLT_EVAL_METHOD to 1 to replicate the existing logic.  As
  previously discussed, it might make sense in coordination with GCC
  to eliminate the historic mistake, avoid excess precision in the
  -fexcess-precision=standard case and make the typedefs match (with a
  NEWS entry, again).

Tested for x86-64 and x86.  Also did compilation-only testing with
build-many-glibcs.py.

	* bits/flt-eval-method.h: New file.
	* sysdeps/m68k/m680x0/bits/flt-eval-method.h: Likewise.
	* sysdeps/s390/bits/flt-eval-method.h: Likewise.
	* sysdeps/x86/bits/flt-eval-method.h: Likewise.
	* math/Makefile (headers): Add bits/flt-eval-method.h.
	* math/math.h: Include <bits/flt-eval-method.h>.
	[__USE_ISOC99] (float_t): Define based on __GLIBC_FLT_EVAL_METHOD.
	[__USE_ISOC99] (double_t): Likewise.
	* bits/mathdef.h (float_t): Remove.
	(double_t): Likewise.
	* sysdeps/aarch64/bits/mathdef.h (float_t): Likewise.
	(double_t): Likewise.
	* sysdeps/alpha/bits/mathdef.h (float_t): Likewise.
	(double_t): Likewise.
	* sysdeps/arm/bits/mathdef.h (float_t): Likewise.
	(double_t): Likewise.
	* sysdeps/hppa/fpu/bits/mathdef.h (float_t): Likewise.
	(double_t): Likewise.
	* sysdeps/ia64/bits/mathdef.h (float_t): Likewise.
	(double_t): Likewise.
	* sysdeps/m68k/m680x0/bits/mathdef.h (float_t): Likewise.
	(double_t): Likewise.
	* sysdeps/mips/bits/mathdef.h (float_t): Likewise.
	(double_t): Likewise.
	* sysdeps/powerpc/bits/mathdef.h (float_t): Likewise.
	(double_t): Likewise.
	* sysdeps/s390/bits/mathdef.h (float_t): Likewise.
	(double_t): Likewise.
	* sysdeps/sh/sh4/bits/mathdef.h (float_t): Likewise.
	(double_t): Likewise.
	* sysdeps/sparc/bits/mathdef.h (float_t): Likewise.
	(double_t): Likewise.
	* sysdeps/tile/bits/mathdef.h (float_t): Likewise.
	(double_t): Likewise.
	* sysdeps/x86/bits/mathdef.h (float_t): Likewise.
	(double_t): Likewise.
2016-11-24 18:44:50 +00:00
argp Installed-header hygiene (BZ#20366): Simple self-contained fixes. 2016-09-23 08:43:55 -04:00
assert Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
benchtests Use -fno-builtin for sqrt benchmark. 2016-10-21 21:18:03 +00:00
bits Refactor float_t, double_t information into bits/flt-eval-method.h. 2016-11-24 18:44:50 +00:00
catgets Fix building glibc master with NDEBUG and --with-cpu. 2016-03-15 23:23:24 -04:00
conform Enable linknamespace testing for libdl and libcrypt. 2016-11-16 22:47:57 +00:00
crypt Fix crypt snprintf namespace (bug 20829). 2016-11-16 22:46:48 +00:00
csu Remove __libc_csu_irel declaration 2016-09-10 15:50:53 +05:30
ctype Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
debug Add tests for fortification of bcopy and bzero. 2016-08-19 09:04:35 -04:00
dirent Deprecate readdir_r, readdir64_r [BZ #19056] 2016-02-20 12:56:55 +01:00
dlfcn Fix warning caused by unused-result in bug-atexit3-lib.cc 2016-10-28 19:26:14 -02:00
elf elf: Assume TLS is initialized in _dl_map_object_from_fd 2016-11-23 13:12:03 +01:00
gmon Installed-header hygiene (BZ#20366): obsolete BSD u_* types. 2016-09-23 08:43:56 -04:00
gnulib Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
grp Don't install the internal header grp-merge.h 2016-07-18 09:33:21 -03:00
gshadow Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
hesiod hesiod: Avoid heap overflow in get_txt_records [BZ #20031] 2016-05-02 16:04:32 +02:00
hurd Fix hurd __access_noerrno implementation. 2016-11-18 16:49:08 -02:00
iconv gconv.h: fix build with GCC 7 2016-11-06 21:33:10 +01:00
iconvdata Bug 20729: Fix building with -Os. 2016-10-29 23:50:56 -04:00
include Fix hurd __access_noerrno implementation. 2016-11-18 16:49:08 -02:00
inet Installed-header hygiene (BZ#20366): conditionally defined structures. 2016-09-23 08:43:56 -04:00
intl hurd: fix pathconf visibility 2016-09-18 23:45:12 +02:00
io New internal function __access_noerrno 2016-11-16 15:53:58 -02:00
libidn Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
libio Fix tst-memstream3 build failure 2016-10-02 10:24:32 -03:00
locale Bug 20729: Include libc-internal.h where required. 2016-10-31 16:46:57 -04:00
localedata localedata: lt_LT: use hyphens in d_fmt [BZ #20497] 2016-08-24 16:07:02 -04:00
login 2016-06-11 Paul Pluzhnikov <ppluzhnikov@google.com> 2016-06-11 14:50:16 -07:00
mach Fix old-style function definition 2016-09-20 23:10:51 +02:00
malloc malloc: Update comments about chunk layout 2016-10-28 22:36:58 +02:00
manual Add setpayload, setpayloadf, setpayloadl. 2016-11-19 00:16:28 +00:00
math Refactor float_t, double_t information into bits/flt-eval-method.h. 2016-11-24 18:44:50 +00:00
mathvec Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
misc Fix multiple definitions of mk[o]stemp[s]64 2016-11-22 13:51:19 +01:00
nis Installed-header hygiene (BZ#20366): Simple self-contained fixes. 2016-09-23 08:43:55 -04:00
nptl Consolidate lseek/lseek64/llseek implementations 2016-11-08 16:04:33 -02:00
nptl_db Bug 20729: Include libc-internal.h where required. 2016-10-31 16:46:57 -04:00
nscd Fix incorrect double-checked locking related to _res_hconf.initialized. 2016-08-18 20:53:37 +02:00
nss Fix incorrect double-checked locking related to _res_hconf.initialized. 2016-08-18 20:53:37 +02:00
po Update PO files. 2016-08-04 11:41:27 -04:00
posix Fix writes past the allocated array bounds in execvpe (BZ#20847) 2016-11-22 10:23:07 -02:00
pwd Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
resolv Bug 20729: Fix build failures on ppc64 and other arches. 2016-11-02 13:01:36 -04:00
resource Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
rt Use libc_ifunc macro for clock_* symbols in librt. 2016-10-07 10:12:47 +02:00
scripts build-many-glibcs: Revert -fno-isolate-erroneous-paths options for tilepro 2016-11-23 12:25:23 -05:00
setjmp Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
shadow Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
signal Installed-header hygiene (BZ#20366): time.h types. 2016-09-23 08:43:56 -04:00
socket Installed-header hygiene (BZ#20366): conditionally defined structures. 2016-09-23 08:43:56 -04:00
soft-fp [soft-fp] Add support for various half-precision conversion routines. 2016-09-21 21:02:54 +00:00
stdio-common Fix crypt snprintf namespace (bug 20829). 2016-11-16 22:46:48 +00:00
stdlib Ignore -Wmaybe-uninitialized in stdlib/bug-getcontext.c. 2016-11-11 21:05:51 +00:00
streams Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
string Correct comments in string.h re strcoll_l, strxfrm_l. 2016-11-16 14:18:32 -05:00
sunrpc Fix build-and-build-again bug in sunrpc tests. 2016-11-14 14:25:11 -05:00
sysdeps Refactor float_t, double_t information into bits/flt-eval-method.h. 2016-11-24 18:44:50 +00:00
sysvipc Installed-header hygiene (BZ#20366): time.h types. 2016-09-23 08:43:56 -04:00
termios Declare tcgetsid for XPG4 (bug 20055). 2016-05-11 18:05:37 +00:00
time Fix -Wformat-length warning in time/tst-strptime2.c 2016-11-02 16:00:39 -07:00
timezone Remove mention of checktab.awk in timezone/README. 2016-03-14 14:11:51 -04:00
wcsmbs Add tst-wcstod-round 2016-08-19 11:17:07 -05:00
wctype Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
.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 Add arm-nacl port. 2015-04-17 09:02:19 -07:00
aclocal.m4 Rename localedir to complocaledir (bug 14259). 2015-11-27 10:22:38 -05:00
BUGS [BZ #5222] 2007-10-28 08:24:07 +00:00
ChangeLog Refactor float_t, double_t information into bits/flt-eval-method.h. 2016-11-24 18:44:50 +00:00
ChangeLog.1
ChangeLog.2
ChangeLog.3
ChangeLog.4
ChangeLog.5 * sysdeps/posix/getaddrinfo.c: Implement configuration file 2006-05-04 06:38:07 +00:00
ChangeLog.6 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.7 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.8 ChangeLog: change Winblowz to Windows 2016-08-10 00:49:28 +08:00
ChangeLog.9
ChangeLog.10 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.11 ChangeLog: change Winblowz to Windows 2016-08-10 00:49:28 +08:00
ChangeLog.12 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.13
ChangeLog.14 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.15
ChangeLog.16 Fix typo in name 2012-06-21 16:45:27 +02:00
ChangeLog.17 Revert "Sun agreed to a change of the license for the RPC code to a BSD-like license." 2010-06-27 19:34:03 -07:00
ChangeLog.old-ports Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-aarch64 Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-aix Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-alpha Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-am33 Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-arm Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-cris Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-hppa Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-ia64 Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-linux-generic Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-m68k Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-microblaze Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-mips Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-powerpc Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-tile Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
config.h.in Add configure check to test if gcc supports attribute ifunc. 2016-10-07 10:02:59 +02:00
config.make.in Avoid running $(CXX) during build to obtain header file paths 2016-09-21 10:45:32 +02:00
configure configure: accept __stack_chk_fail_local for ssp support too [BZ #20662] 2016-11-15 14:15:19 -05:00
configure.ac configure: accept __stack_chk_fail_local for ssp support too [BZ #20662] 2016-11-15 14:15:19 -05:00
CONFORMANCE Move __STDC_* predefined macros from features.h to stdc-predef.h. 2012-02-22 12:53:04 +00:00
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
cppflags-iterator.mk
extra-lib.mk Remove NOT_IN_libc 2014-11-24 15:03:45 +05:30
extra-modules.mk Remove NOT_IN_libc 2014-11-24 15:03:45 +05:30
gen-locales.mk Split locale generation snippet into a separate file 2015-05-13 13:05:28 +05:30
INSTALL Add configure check to test if gcc supports attribute ifunc. 2016-10-07 10:02:59 +02:00
libc-abis A few more archs have IFUNC support. 2010-03-17 02:43:12 -07:00
LICENSES Expand LICENSES file. 2012-12-05 21:56:15 +00:00
Makeconfig Generate .op pattern rules for profiling builds only 2016-09-21 10:45:19 +02:00
Makefile Installed header hygiene (BZ#20366): Test of installed headers. 2016-09-23 08:43:56 -04:00
Makefile.in New make target to only build benchmark binaries 2016-04-20 10:23:28 +05:30
Makerules Avoid running $(CXX) during build to obtain header file paths 2016-09-21 10:45:32 +02:00
NAMESPACE
NEWS More NEWS entries / fixes for float_t / double_t changes. 2016-11-23 21:30:04 +00:00
o-iterator.mk
PROJECTS
README Require Linux 3.2 except on x86 / x86_64, 3.2 headers everywhere. 2016-02-24 17:15:12 +00:00
Rules Do not generate UNRESOLVED results for run-built-tests = no. 2016-11-04 21:29:00 +00:00
shlib-versions This is update for configure, build and install of vector math library. 2015-05-14 18:07:06 +03:00
test-skeleton.c Document do_test in test-skeleton.c 2016-11-07 08:28:52 -08:00
version.h Open development for 2.25. 2016-08-01 23:00:21 -04:00
WUR-REPORT * posix/unistd.h (setuid, setreuid, seteuid, setresuid): 2012-08-01 18:12:58 +02:00

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