From 412cb261b0d66ef5251d7d1c8276b5c522d943b7 Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Wed, 3 Aug 2016 22:21:37 +0000 Subject: [PATCH] Support __STDC_WANT_IEC_60559_FUNCS_EXT__ feature test macro. This patch implements support for the __STDC_WANT_IEC_60559_FUNCS_EXT__ feature test macro, following the __GLIBC_USE approach used for other ISO C feature test macros. Currently this only affects the exp10 functions (which glibc has had for a long time). Tested for x86_64 and x86 (testsuite, and that installed stripped shared libraries are unchanged by the patch). * bits/libc-header-start.h (__GLIBC_USE_IEC_60559_FUNCS_EXT): New macro. * include/features.h (__STDC_WANT_IEC_60559_FUNCS_EXT__): Document. * manual/creature.texi (__STDC_WANT_IEC_60559_FUNCS_EXT__): Document macro. * manual/math.texi (exp10): Document as ISO from TS 18661-4:2015. (exp10f): Likewise. (exp10l): Likewise. * math/bits/mathcalls.h (exp10): Declare if [__GLIBC_USE (IEC_60559_FUNCS_EXT)], not [__USE_GNU]. --- ChangeLog | 12 ++++++++++++ NEWS | 5 +++++ bits/libc-header-start.h | 9 +++++++++ include/features.h | 2 ++ manual/creature.texi | 9 +++++++++ manual/math.texi | 9 +++++---- math/bits/mathcalls.h | 6 ++++-- 7 files changed, 46 insertions(+), 6 deletions(-) diff --git a/ChangeLog b/ChangeLog index 954af379c5..ac692dc9e7 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,17 @@ 2016-08-03 Joseph Myers + * bits/libc-header-start.h (__GLIBC_USE_IEC_60559_FUNCS_EXT): New + macro. + * include/features.h (__STDC_WANT_IEC_60559_FUNCS_EXT__): + Document. + * manual/creature.texi (__STDC_WANT_IEC_60559_FUNCS_EXT__): + Document macro. + * manual/math.texi (exp10): Document as ISO from TS 18661-4:2015. + (exp10f): Likewise. + (exp10l): Likewise. + * math/bits/mathcalls.h (exp10): Declare if + [__GLIBC_USE (IEC_60559_FUNCS_EXT)], not [__USE_GNU]. + * manual/arith.texi (nextup): Fix typo in last change. 2016-08-03 Zack Weinberg diff --git a/NEWS b/NEWS index 25c771df2e..fe9ff1c451 100644 --- a/NEWS +++ b/NEWS @@ -17,6 +17,11 @@ Version 2.25 from that TS. Note that most features from that TS are not supported by the GNU C Library. +* The feature test macro __STDC_WANT_IEC_60559_FUNCS_EXT__, from ISO/IEC TS + 18661-4:2015, is supported to enable declarations of functions and macros + from that TS. Note that most features from that TS are not supported by + the GNU C Library. + * The inclusion of by is deprecated. This means that in a future release, the macros “major”, “minor”, and “makedev” will only be available from . diff --git a/bits/libc-header-start.h b/bits/libc-header-start.h index 6a5850526c..ee6a876d82 100644 --- a/bits/libc-header-start.h +++ b/bits/libc-header-start.h @@ -50,3 +50,12 @@ #else # define __GLIBC_USE_IEC_60559_BFP_EXT 0 #endif + +/* ISO/IEC TS 18661-4:2015 defines the + __STDC_WANT_IEC_60559_FUNCS_EXT__ macro. */ +#undef __GLIBC_USE_IEC_60559_FUNCS_EXT +#if defined __USE_GNU || defined __STDC_WANT_IEC_60559_FUNCS_EXT__ +# define __GLIBC_USE_IEC_60559_FUNCS_EXT 1 +#else +# define __GLIBC_USE_IEC_60559_FUNCS_EXT 0 +#endif diff --git a/include/features.h b/include/features.h index 554c5c888a..650d4c5e12 100644 --- a/include/features.h +++ b/include/features.h @@ -26,6 +26,8 @@ _ISOC11_SOURCE Extensions to ISO C99 from ISO C11. __STDC_WANT_LIB_EXT2__ Extensions to ISO C99 from TR 27431-2:2010. __STDC_WANT_IEC_60559_BFP_EXT__ Extensions to ISO C11 from TS 18661-1:2014. + __STDC_WANT_IEC_60559_FUNCS_EXT__ Extensions to ISO C11 from + TS 18661-4:2015. _POSIX_SOURCE IEEE Std 1003.1. _POSIX_C_SOURCE If ==1, like _POSIX_SOURCE; if >=2 add IEEE Std 1003.2; if >=199309L, add IEEE Std 1003.1b-1993; diff --git a/manual/creature.texi b/manual/creature.texi index 61b17ce22b..257f8718b1 100644 --- a/manual/creature.texi +++ b/manual/creature.texi @@ -182,6 +182,15 @@ are enabled. Only some of the features from this TS are supported by @theglibc{}. @end defvr +@comment (none) +@comment ISO +@defvr Macro __STDC_WANT_IEC_60559_FUNCS_EXT__ +If you define this macro, features from ISO/IEC TS 18661-4:2015 +(Floating-point extensions for C: Supplementary functions) are +enabled. Only some of the features from this TS are supported by +@theglibc{}. +@end defvr + @comment (none) @comment GNU @defvr Macro _GNU_SOURCE diff --git a/manual/math.texi b/manual/math.texi index 5c9f7b9f1c..d689820c6c 100644 --- a/manual/math.texi +++ b/manual/math.texi @@ -480,13 +480,13 @@ Mathematically, @code{exp2 (x)} is the same as @code{exp (x * log (2))}. @end deftypefun @comment math.h -@comment GNU +@comment ISO @deftypefun double exp10 (double @var{x}) @comment math.h -@comment GNU +@comment ISO @deftypefunx float exp10f (float @var{x}) @comment math.h -@comment GNU +@comment ISO @deftypefunx {long double} exp10l (long double @var{x}) @comment math.h @comment GNU @@ -501,7 +501,8 @@ Mathematically, @code{exp2 (x)} is the same as @code{exp (x * log (2))}. These functions compute @code{10} raised to the power @var{x}. Mathematically, @code{exp10 (x)} is the same as @code{exp (x * log (10))}. -These functions are GNU extensions. The name @code{exp10} is +The @code{exp10} functions are from TS 18661-4:2015; the @code{pow10} +names are GNU extensions. The name @code{exp10} is preferred, since it is analogous to @code{exp} and @code{exp2}. @end deftypefun diff --git a/math/bits/mathcalls.h b/math/bits/mathcalls.h index e1c0521ae8..951a3d0090 100644 --- a/math/bits/mathcalls.h +++ b/math/bits/mathcalls.h @@ -115,9 +115,11 @@ __MATHCALL (log10,, (_Mdouble_ __x)); __MATHCALL (modf,, (_Mdouble_ __x, _Mdouble_ *__iptr)) __nonnull ((2)); _Mdouble_END_NAMESPACE -#ifdef __USE_GNU -/* A function missing in all standards: compute exponent to base ten. */ +#if __GLIBC_USE (IEC_60559_FUNCS_EXT) +/* Compute exponent to base ten. */ __MATHCALL (exp10,, (_Mdouble_ __x)); +#endif +#ifdef __USE_GNU /* Another name occasionally used. */ __MATHCALL (pow10,, (_Mdouble_ __x)); #endif