Support __STDC_WANT_IEC_60559_BFP_EXT__ feature test macro.

This patch implements support for the __STDC_WANT_IEC_60559_BFP_EXT__
feature test macro from ISO/IEC 18661-1:2014, following the
__GLIBC_USE approach now used for __STDC_WANT_LIB_EXT2__.  For this
macro, the relevant consideration is whether it is defined or
undefined when an affected header is included (not what its value is
if defined, and not whether it's defined or undefined when any other
unaffected system header is included).

Currently this macro only affects the issignaling macro and the nextup
and nextdown functions (so they can be enabled by defining this macro,
not just by defining _GNU_SOURCE as previously).  Any further features
from this TS added in future would also be conditioned on this macro.

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_BFP_EXT): New
	macro.
	* include/features.h (__STDC_WANT_IEC_60559_BFP_EXT__): Document.
	* manual/arith.texi (issignaling): Document as ISO from TS
	18661-1:2014.
	(nextup): Likewise.
	(nextupf): Likewise.
	(nextupl): Likewise.
	(nextdown): Likewise.
	(nextdownf): Likewise.
	(nextdownl): Likewise.
	* manual/creature.texi (__STDC_WANT_IEC_60559_BFP_EXT__): Document
	macro.
	* math/math.h: Define
	__GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION and include
	<bits/libc-header-start.h> instead of including <features.h>.
	(issignaling): Define if [__GLIBC_USE (IEC_60559_BFP_EXT)], not
	[__USE_GNU].
	* math/bits/mathcalls.h (nextdown): Declare if
	[__GLIBC_USE (IEC_60559_BFP_EXT)], not [__USE_GNU].
	(nextup): Likewise.
	(__issignaling): Likewise.
This commit is contained in:
Joseph Myers 2016-08-03 17:30:41 +00:00
parent f2de695bf6
commit bf91be88ea
8 changed files with 65 additions and 16 deletions

View File

@ -1,3 +1,28 @@
2016-08-03 Joseph Myers <joseph@codesourcery.com>
* bits/libc-header-start.h (__GLIBC_USE_IEC_60559_BFP_EXT): New
macro.
* include/features.h (__STDC_WANT_IEC_60559_BFP_EXT__): Document.
* manual/arith.texi (issignaling): Document as ISO from TS
18661-1:2014.
(nextup): Likewise.
(nextupf): Likewise.
(nextupl): Likewise.
(nextdown): Likewise.
(nextdownf): Likewise.
(nextdownl): Likewise.
* manual/creature.texi (__STDC_WANT_IEC_60559_BFP_EXT__): Document
macro.
* math/math.h: Define
__GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION and include
<bits/libc-header-start.h> instead of including <features.h>.
(issignaling): Define if [__GLIBC_USE (IEC_60559_BFP_EXT)], not
[__USE_GNU].
* math/bits/mathcalls.h (nextdown): Declare if
[__GLIBC_USE (IEC_60559_BFP_EXT)], not [__USE_GNU].
(nextup): Likewise.
(__issignaling): Likewise.
2016-08-03 Paul E. Murphy <murphyp@linux.vnet.ibm.com>
* s_ccoshf.c (__ccoshf): Remove FE_INVALID

5
NEWS
View File

@ -12,6 +12,11 @@ Version 2.25
TR. Note that not all functions from that TR are supported by the GNU C
Library.
* The feature test macro __STDC_WANT_IEC_60559_BFP_EXT__, from ISO/IEC TS
18661-1:2014, 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.
Security related changes:
[Add security related changes here]

View File

@ -41,3 +41,12 @@
#else
# define __GLIBC_USE_LIB_EXT2 0
#endif
/* ISO/IEC TS 18661-1:2014 defines the __STDC_WANT_IEC_60559_BFP_EXT__
macro. */
#undef __GLIBC_USE_IEC_60559_BFP_EXT
#if defined __USE_GNU || defined __STDC_WANT_IEC_60559_BFP_EXT__
# define __GLIBC_USE_IEC_60559_BFP_EXT 1
#else
# define __GLIBC_USE_IEC_60559_BFP_EXT 0
#endif

View File

@ -25,6 +25,7 @@
_ISOC99_SOURCE Extensions to ISO C89 from ISO C99.
_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.
_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;

View File

@ -397,12 +397,11 @@ to
@end deftypefn
@comment math.h
@comment GNU
@comment ISO
@deftypefn {Macro} int issignaling (@emph{float-type} @var{x})
@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
This macro returns a nonzero value if @var{x} is a signaling NaN
(sNaN). It is based on draft TS 18661 and currently enabled as a GNU
extension.
(sNaN). It is from TS 18661-1:2014.
@end deftypefn
Another set of floating-point classification functions was provided by
@ -1703,13 +1702,13 @@ double}.
@end deftypefun
@comment math.h
@comment GNU
@comment ISO
@deftypefun double nextup (double @var{x})
@comment math.h
@comment GNU
@comment ISO
@deftypefunx float nextupf (float @var{x})
@comment math.h
@comment GNU
@comment ISO
@deftypefunx {long double} nextupl (long double @var{x})
@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
The @code{nextup} function returns the next representable neighbor of @var{x}
@ -1718,18 +1717,18 @@ subnormal number in the type of @var{x} the function returns @code{-0}. If
@math{@var{x} = @code{0}} the function returns the smallest positive subnormal
number in the type of @var{x}. If @var{x} is NaN, NaN is returned.
If @var{x} is @math{+@infinity{}}, @math{+@infinity{}} is returned.
@code{nextup} is based on TS 18661 and currently enabled as a GNU extension.
@code{nextup} from TS 18661-1:2014.
@code{nextup} never raises an exception except for signaling NaNs.
@end deftypefun
@comment math.h
@comment GNU
@comment ISO
@deftypefun double nextdown (double @var{x})
@comment math.h
@comment GNU
@comment ISO
@deftypefunx float nextdownf (float @var{x})
@comment math.h
@comment GNU
@comment ISO
@deftypefunx {long double} nextdownl (long double @var{x})
@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
The @code{nextdown} function returns the next representable neighbor of @var{x}
@ -1738,7 +1737,7 @@ subnormal number in the type of @var{x} the function returns @code{+0}. If
@math{@var{x} = @code{0}} the function returns the smallest negative subnormal
number in the type of @var{x}. If @var{x} is NaN, NaN is returned.
If @var{x} is @math{-@infinity{}}, @math{-@infinity{}} is returned.
@code{nextdown} is based on TS 18661 and currently enabled as a GNU extension.
@code{nextdown} is from TS 18661-1:2014.
@code{nextdown} never raises an exception except for signaling NaNs.
@end deftypefun

View File

@ -173,6 +173,15 @@ TR 24731-2:2010 (Dynamic Allocation Functions) are enabled. Only some
of the features from this TR are supported by @theglibc{}.
@end defvr
@comment (none)
@comment ISO
@defvr Macro __STDC_WANT_IEC_60559_BFP_EXT__
If you define this macro, features from ISO/IEC TS 18661-1:2014
(Floating-point extensions for C: Binary floating-point arithmetic)
are enabled. Only some of the features from this TS are supported by
@theglibc{}.
@end defvr
@comment (none)
@comment GNU
@defvr Macro _GNU_SOURCE

View File

@ -294,7 +294,7 @@ __MATHCALLX (nextafter,, (_Mdouble_ __x, _Mdouble_ __y), (__const__));
__MATHCALLX (nexttoward,, (_Mdouble_ __x, long double __y), (__const__));
# endif
#ifdef __USE_GNU
#if __GLIBC_USE (IEC_60559_BFP_EXT)
/* Return X - epsilon. */
__MATHCALL (nextdown,, (_Mdouble_ __x));
/* Return X + epsilon. */
@ -377,7 +377,7 @@ __MATHCALL (fma,, (_Mdouble_ __x, _Mdouble_ __y, _Mdouble_ __z));
__END_NAMESPACE_C99
#endif
#ifdef __USE_GNU
#if __GLIBC_USE (IEC_60559_BFP_EXT)
/* Test for signaling NaN. */
__MATHDECL_1 (int, __issignaling,, (_Mdouble_ __value))
__attribute__ ((__const__));

View File

@ -23,7 +23,8 @@
#ifndef _MATH_H
#define _MATH_H 1
#include <features.h>
#define __GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION
#include <bits/libc-header-start.h>
__BEGIN_DECLS
@ -328,7 +329,7 @@ enum
#endif /* Use ISO C99. */
#ifdef __USE_GNU
#if __GLIBC_USE (IEC_60559_BFP_EXT)
/* Return nonzero value if X is a signaling NaN. */
# ifdef __NO_LONG_DOUBLE_MATH
# define issignaling(x) \
@ -340,7 +341,7 @@ enum
: sizeof (x) == sizeof (double) \
? __issignaling (x) : __issignalingl (x))
# endif
#endif /* Use GNU. */
#endif /* Use IEC_60559_BFP_EXT. */
#ifdef __USE_MISC
/* Support for various different standard error handling behaviors. */