Add SNAN, SNANF, SNANL macros.
TS 18661-1 defines SNAN macros for signaling NaN values, suitable for
use in static initializers. This patch adds them to glibc's <math.h>
(provided you are building with GCC 3.3 or later; no attempt is made
to provide any kind of nonconforming fallback for older compilers
without the __builtin_nans functions).
Tested for x86_64 and x86.
* math/math.h
[__GLIBC_USE (IEC_60559_BFP_EXT) && __GNUC_PREREQ (3, 3)] (SNANF):
New macro.
[__GLIBC_USE (IEC_60559_BFP_EXT) && __GNUC_PREREQ (3, 3)] (SNAN):
Likewise.
[__GLIBC_USE (IEC_60559_BFP_EXT) && __GNUC_PREREQ (3, 3)] (SNANL):
Likewise.
* manual/arith.texi (Infinity and NaN): Document SNANF, SNAN and
SNANL.
* math/test-double.h (snan_value_MACRO): New macro.
* math/test-float.h (snan_value_MACRO): Likewise.
* math/test-ldouble.h (snan_value_MACRO): Likewise.
* math/libm-test.inc (issignaling_test_data): Add tests of
snan_value_MACRO.