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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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| .. | ||
| bits | ||
| fpu | ||
| ieee754 | ||
| include/sys | ||
| mips32 | ||
| mips64 | ||
| nptl | ||
| sys | ||
| __longjmp.c | ||
| abort-instr.h | ||
| add_n.S | ||
| addmul_1.S | ||
| atomic-machine.h | ||
| backtrace.c | ||
| bsd-_setjmp.S | ||
| bsd-setjmp.S | ||
| configure | ||
| configure.ac | ||
| dl-dtprocnum.h | ||
| dl-machine-reject-phdr.h | ||
| dl-machine.h | ||
| dl-procinfo.c | ||
| dl-procinfo.h | ||
| dl-tls.h | ||
| dl-trampoline.c | ||
| fpregdef.h | ||
| fpu_control.h | ||
| gccframe.h | ||
| Implies | ||
| jmpbuf-unwind.h | ||
| ldsodefs.h | ||
| libc-tls.c | ||
| linkmap.h | ||
| localplt.data | ||
| lshift.S | ||
| machine-gmon.h | ||
| Makefile | ||
| math_private.h | ||
| math-tests.h | ||
| memcpy.S | ||
| memset.S | ||
| memusage.h | ||
| mul_1.S | ||
| nan-high-order-bit.h | ||
| preconfigure | ||
| regdef.h | ||
| rshift.S | ||
| setjmp_aux.c | ||
| setjmp.S | ||
| sgidefs.h | ||
| sotruss-lib.c | ||
| stackinfo.h | ||
| start.S | ||
| strcmp.S | ||
| sub_n.S | ||
| submul_1.S | ||
| tininess.h | ||
| tls-macros.h | ||
| tst-abi-fp32mod.c | ||
| tst-abi-fp64amod.c | ||
| tst-abi-fp64mod.c | ||
| tst-abi-fpxxmod.c | ||
| tst-abi-fpxxomod.c | ||
| tst-abi-interlink.c | ||
| tst-audit.h | ||
| tst-mode-switch-1.c | ||
| tst-mode-switch-2.c | ||
| tst-mode-switch-3.c | ||