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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. |
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| .. | ||
| byteswap-16.h | ||
| byteswap.h | ||
| confname.h | ||
| dirent.h | ||
| dlfcn.h | ||
| elfclass.h | ||
| endian.h | ||
| environments.h | ||
| errno.h | ||
| fcntl.h | ||
| fenv.h | ||
| fenvinline.h | ||
| flt-eval-method.h | ||
| huge_val.h | ||
| huge_valf.h | ||
| huge_vall.h | ||
| hwcap.h | ||
| in.h | ||
| inf.h | ||
| ioctl-types.h | ||
| ioctls.h | ||
| ipc.h | ||
| ipctypes.h | ||
| iscanonical.h | ||
| libc-header-start.h | ||
| libm-simd-decl-stubs.h | ||
| link.h | ||
| local_lim.h | ||
| math-vector.h | ||
| mathdef.h | ||
| mathinline.h | ||
| mman-linux.h | ||
| mman.h | ||
| mqueue.h | ||
| msq.h | ||
| nan.h | ||
| netdb.h | ||
| param.h | ||
| poll.h | ||
| posix_opt.h | ||
| pthreadtypes.h | ||
| resource.h | ||
| sched.h | ||
| select.h | ||
| sem.h | ||
| setjmp.h | ||
| shm.h | ||
| sigaction.h | ||
| sigcontext.h | ||
| siginfo.h | ||
| signum.h | ||
| sigset.h | ||
| sigstack.h | ||
| sigthread.h | ||
| sockaddr.h | ||
| socket.h | ||
| stat.h | ||
| statfs.h | ||
| statvfs.h | ||
| stdlib-bsearch.h | ||
| string.h | ||
| stropts.h | ||
| sys_errlist.h | ||
| syslog-path.h | ||
| sysmacros.h | ||
| termios.h | ||
| time.h | ||
| types.h | ||
| typesizes.h | ||
| uio.h | ||
| ustat.h | ||
| utmp.h | ||
| utsname.h | ||
| waitflags.h | ||
| waitstatus.h | ||
| wchar.h | ||
| wordsize.h | ||
| xtitypes.h | ||