mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-24 02:03:35 +08:00
93eb85ceb2
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. |
||
---|---|---|
argp | ||
assert | ||
benchtests | ||
bits | ||
catgets | ||
conform | ||
crypt | ||
csu | ||
ctype | ||
debug | ||
dirent | ||
dlfcn | ||
elf | ||
gmon | ||
gnulib | ||
grp | ||
gshadow | ||
hesiod | ||
hurd | ||
iconv | ||
iconvdata | ||
include | ||
inet | ||
intl | ||
io | ||
libidn | ||
libio | ||
locale | ||
localedata | ||
login | ||
mach | ||
malloc | ||
manual | ||
math | ||
mathvec | ||
misc | ||
nis | ||
nptl | ||
nptl_db | ||
nscd | ||
nss | ||
po | ||
posix | ||
pwd | ||
resolv | ||
resource | ||
rt | ||
scripts | ||
setjmp | ||
shadow | ||
signal | ||
socket | ||
soft-fp | ||
stdio-common | ||
stdlib | ||
streams | ||
string | ||
sunrpc | ||
sysdeps | ||
sysvipc | ||
termios | ||
time | ||
timezone | ||
wcsmbs | ||
wctype | ||
.gitattributes | ||
.gitignore | ||
abi-tags | ||
aclocal.m4 | ||
BUGS | ||
ChangeLog | ||
ChangeLog.1 | ||
ChangeLog.2 | ||
ChangeLog.3 | ||
ChangeLog.4 | ||
ChangeLog.5 | ||
ChangeLog.6 | ||
ChangeLog.7 | ||
ChangeLog.8 | ||
ChangeLog.9 | ||
ChangeLog.10 | ||
ChangeLog.11 | ||
ChangeLog.12 | ||
ChangeLog.13 | ||
ChangeLog.14 | ||
ChangeLog.15 | ||
ChangeLog.16 | ||
ChangeLog.17 | ||
ChangeLog.old-ports | ||
ChangeLog.old-ports-aarch64 | ||
ChangeLog.old-ports-aix | ||
ChangeLog.old-ports-alpha | ||
ChangeLog.old-ports-am33 | ||
ChangeLog.old-ports-arm | ||
ChangeLog.old-ports-cris | ||
ChangeLog.old-ports-hppa | ||
ChangeLog.old-ports-ia64 | ||
ChangeLog.old-ports-linux-generic | ||
ChangeLog.old-ports-m68k | ||
ChangeLog.old-ports-microblaze | ||
ChangeLog.old-ports-mips | ||
ChangeLog.old-ports-powerpc | ||
ChangeLog.old-ports-tile | ||
config.h.in | ||
config.make.in | ||
configure | ||
configure.ac | ||
CONFORMANCE | ||
COPYING | ||
COPYING.LIB | ||
cppflags-iterator.mk | ||
extra-lib.mk | ||
extra-modules.mk | ||
gen-locales.mk | ||
INSTALL | ||
libc-abis | ||
LICENSES | ||
Makeconfig | ||
Makefile | ||
Makefile.in | ||
Makerules | ||
NAMESPACE | ||
NEWS | ||
o-iterator.mk | ||
PROJECTS | ||
README | ||
Rules | ||
shlib-versions | ||
test-skeleton.c | ||
version.h | ||
WUR-REPORT |
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 on all architectures except i[4567]86 and x86_64, where Linux kernel version 2.6.32 or later suffices. 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. The GNU C Library is free software. See the file COPYING.LIB for copying conditions, and LICENSES for notices about a few contributions that require these additional notices to be distributed. License copyright years may be listed using range notation, e.g., 1996-2015, indicating that every year in the range, inclusive, is a copyrightable year that would otherwise be listed individually.