1 /* A GNU-like <math.h>.
3 Copyright (C) 2002-2003, 2007-2011 Free Software Foundation, Inc.
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 @PRAGMA_SYSTEM_HEADER@
25 /* The include_next requires a split double-inclusion guard. */
26 #@INCLUDE_NEXT_AS_FIRST_DIRECTIVE@ @NEXT_AS_FIRST_DIRECTIVE_MATH_H@
32 /* The definitions of _GL_FUNCDECL_RPL etc. are copied here. */
34 /* The definition of _GL_ARG_NONNULL is copied here. */
36 /* The definition of _GL_WARN_ON_USE is copied here. */
38 /* Helper macros to define a portability warning for the
39 classification macro FUNC called with VALUE. POSIX declares the
40 classification macros with an argument of real-floating (that is,
41 one of float, double, or long double). */
42 #define _GL_WARN_REAL_FLOATING_DECL(func) \
44 rpl_ ## func ## f (float f) \
49 rpl_ ## func ## d (double d) \
54 rpl_ ## func ## l (long double l) \
58 _GL_WARN_ON_USE (rpl_ ## func ## f, #func " is unportable - " \
59 "use gnulib module " #func " for portability"); \
60 _GL_WARN_ON_USE (rpl_ ## func ## d, #func " is unportable - " \
61 "use gnulib module " #func " for portability"); \
62 _GL_WARN_ON_USE (rpl_ ## func ## l, #func " is unportable - " \
63 "use gnulib module " #func " for portability")
64 #define _GL_WARN_REAL_FLOATING_IMPL(func, value) \
65 (sizeof (value) == sizeof (float) ? rpl_ ## func ## f (value) \
66 : sizeof (value) == sizeof (double) ? rpl_ ## func ## d (value) \
67 : rpl_ ## func ## l (value))
70 /* POSIX allows platforms that don't support NAN. But all major
71 machines in the past 15 years have supported something close to
72 IEEE NaN, so we define this unconditionally. We also must define
73 it on platforms like Solaris 10, where NAN is present but defined
74 as a function pointer rather than a floating point constant. */
75 #if !defined NAN || @REPLACE_NAN@
77 /* The Compaq (ex-DEC) C 6.4 compiler chokes on the expression 0.0 / 0.0. */
82 static float zero = 0.0f;
87 # define NAN (0.0f / 0.0f)
91 /* Solaris 10 defines HUGE_VAL, but as a function pointer rather
92 than a floating point constant. */
93 #if @REPLACE_HUGE_VAL@
95 # define HUGE_VAL (1.0 / 0.0)
102 If x finite and nonzero: 0.5 <= |mantissa| < 1.0.
103 If x is zero: mantissa = x, exp = 0.
104 If x is infinite or NaN: mantissa = x, exp unspecified.
105 Store exp in *EXPPTR and return mantissa. */
108 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
109 # define frexp rpl_frexp
111 _GL_FUNCDECL_RPL (frexp, double, (double x, int *expptr) _GL_ARG_NONNULL ((2)));
112 _GL_CXXALIAS_RPL (frexp, double, (double x, int *expptr));
114 _GL_CXXALIAS_SYS (frexp, double, (double x, int *expptr));
116 _GL_CXXALIASWARN (frexp);
117 #elif defined GNULIB_POSIXCHECK
119 /* Assume frexp is always declared. */
120 _GL_WARN_ON_USE (frexp, "frexp is unportable - "
121 "use gnulib module frexp for portability");
126 # if !@HAVE_DECL_LOGB@
127 _GL_EXTERN_C double logb (double x);
129 #elif defined GNULIB_POSIXCHECK
131 # if HAVE_RAW_DECL_LOGB
132 _GL_WARN_ON_USE (logb, "logb is unportable - "
133 "use gnulib module logb for portability");
139 # if !@HAVE_ACOSL@ || !@HAVE_DECL_ACOSL@
140 _GL_FUNCDECL_SYS (acosl, long double, (long double x));
142 _GL_CXXALIAS_SYS (acosl, long double, (long double x));
143 _GL_CXXALIASWARN (acosl);
144 #elif defined GNULIB_POSIXCHECK
146 # if HAVE_RAW_DECL_ACOSL
147 _GL_WARN_ON_USE (acosl, "acosl is unportable - "
148 "use gnulib module mathl for portability");
154 # if !@HAVE_ASINL@ || !@HAVE_DECL_ASINL@
155 _GL_FUNCDECL_SYS (asinl, long double, (long double x));
157 _GL_CXXALIAS_SYS (asinl, long double, (long double x));
158 _GL_CXXALIASWARN (asinl);
159 #elif defined GNULIB_POSIXCHECK
161 # if HAVE_RAW_DECL_ASINL
162 _GL_WARN_ON_USE (asinl, "asinl is unportable - "
163 "use gnulib module mathl for portability");
169 # if !@HAVE_ATANL@ || !@HAVE_DECL_ATANL@
170 _GL_FUNCDECL_SYS (atanl, long double, (long double x));
172 _GL_CXXALIAS_SYS (atanl, long double, (long double x));
173 _GL_CXXALIASWARN (atanl);
174 #elif defined GNULIB_POSIXCHECK
176 # if HAVE_RAW_DECL_ATANL
177 _GL_WARN_ON_USE (atanl, "atanl is unportable - "
178 "use gnulib module mathl for portability");
185 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
186 # define ceilf rpl_ceilf
188 _GL_FUNCDECL_RPL (ceilf, float, (float x));
189 _GL_CXXALIAS_RPL (ceilf, float, (float x));
191 # if !@HAVE_DECL_CEILF@
192 _GL_FUNCDECL_SYS (ceilf, float, (float x));
194 _GL_CXXALIAS_SYS (ceilf, float, (float x));
196 _GL_CXXALIASWARN (ceilf);
197 #elif defined GNULIB_POSIXCHECK
199 # if HAVE_RAW_DECL_CEILF
200 _GL_WARN_ON_USE (ceilf, "ceilf is unportable - "
201 "use gnulib module ceilf for portability");
207 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
208 # define ceil rpl_ceil
210 _GL_FUNCDECL_RPL (ceil, double, (double x));
211 _GL_CXXALIAS_RPL (ceil, double, (double x));
213 _GL_CXXALIAS_SYS (ceil, double, (double x));
215 _GL_CXXALIASWARN (ceil);
220 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
221 # define ceill rpl_ceill
223 _GL_FUNCDECL_RPL (ceill, long double, (long double x));
224 _GL_CXXALIAS_RPL (ceill, long double, (long double x));
226 # if !@HAVE_DECL_CEILL@
227 _GL_FUNCDECL_SYS (ceill, long double, (long double x));
229 _GL_CXXALIAS_SYS (ceill, long double, (long double x));
231 _GL_CXXALIASWARN (ceill);
232 #elif defined GNULIB_POSIXCHECK
234 # if HAVE_RAW_DECL_CEILL
235 _GL_WARN_ON_USE (ceill, "ceill is unportable - "
236 "use gnulib module ceill for portability");
242 # if !@HAVE_COSL@ || !@HAVE_DECL_COSL@
243 _GL_FUNCDECL_SYS (cosl, long double, (long double x));
245 _GL_CXXALIAS_SYS (cosl, long double, (long double x));
246 _GL_CXXALIASWARN (cosl);
247 #elif defined GNULIB_POSIXCHECK
249 # if HAVE_RAW_DECL_COSL
250 _GL_WARN_ON_USE (cosl, "cosl is unportable - "
251 "use gnulib module mathl for portability");
257 # if !@HAVE_EXPL@ || !@HAVE_DECL_EXPL@
258 _GL_FUNCDECL_SYS (expl, long double, (long double x));
260 _GL_CXXALIAS_SYS (expl, long double, (long double x));
261 _GL_CXXALIASWARN (expl);
262 #elif defined GNULIB_POSIXCHECK
264 # if HAVE_RAW_DECL_EXPL
265 _GL_WARN_ON_USE (expl, "expl is unportable - "
266 "use gnulib module mathl for portability");
272 # if @REPLACE_FLOORF@
273 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
274 # define floorf rpl_floorf
276 _GL_FUNCDECL_RPL (floorf, float, (float x));
277 _GL_CXXALIAS_RPL (floorf, float, (float x));
279 # if !@HAVE_DECL_FLOORF@
280 _GL_FUNCDECL_SYS (floorf, float, (float x));
282 _GL_CXXALIAS_SYS (floorf, float, (float x));
284 _GL_CXXALIASWARN (floorf);
285 #elif defined GNULIB_POSIXCHECK
287 # if HAVE_RAW_DECL_FLOORF
288 _GL_WARN_ON_USE (floorf, "floorf is unportable - "
289 "use gnulib module floorf for portability");
295 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
296 # define floor rpl_floor
298 _GL_FUNCDECL_RPL (floor, double, (double x));
299 _GL_CXXALIAS_RPL (floor, double, (double x));
301 _GL_CXXALIAS_SYS (floor, double, (double x));
303 _GL_CXXALIASWARN (floor);
307 # if @REPLACE_FLOORL@
308 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
309 # define floorl rpl_floorl
311 _GL_FUNCDECL_RPL (floorl, long double, (long double x));
312 _GL_CXXALIAS_RPL (floorl, long double, (long double x));
314 # if !@HAVE_DECL_FLOORL@
315 _GL_FUNCDECL_SYS (floorl, long double, (long double x));
317 _GL_CXXALIAS_SYS (floorl, long double, (long double x));
319 _GL_CXXALIASWARN (floorl);
320 #elif defined GNULIB_POSIXCHECK
322 # if HAVE_RAW_DECL_FLOORL
323 _GL_WARN_ON_USE (floorl, "floorl is unportable - "
324 "use gnulib module floorl for portability");
332 If x finite and nonzero: 0.5 <= |mantissa| < 1.0.
333 If x is zero: mantissa = x, exp = 0.
334 If x is infinite or NaN: mantissa = x, exp unspecified.
335 Store exp in *EXPPTR and return mantissa. */
336 #if @GNULIB_FREXPL@ && @REPLACE_FREXPL@
337 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
338 # define frexpl rpl_frexpl
340 _GL_FUNCDECL_RPL (frexpl, long double,
341 (long double x, int *expptr) _GL_ARG_NONNULL ((2)));
342 _GL_CXXALIAS_RPL (frexpl, long double, (long double x, int *expptr));
344 # if !@HAVE_DECL_FREXPL@
345 _GL_FUNCDECL_SYS (frexpl, long double,
346 (long double x, int *expptr) _GL_ARG_NONNULL ((2)));
349 _GL_CXXALIAS_SYS (frexpl, long double, (long double x, int *expptr));
352 #if @GNULIB_FREXPL@ && !(@REPLACE_FREXPL@ && !@HAVE_DECL_FREXPL@)
353 _GL_CXXALIASWARN (frexpl);
355 #if !@GNULIB_FREXPL@ && defined GNULIB_POSIXCHECK
357 # if HAVE_RAW_DECL_FREXPL
358 _GL_WARN_ON_USE (frexpl, "frexpl is unportable - "
359 "use gnulib module frexpl for portability");
364 /* Return x * 2^exp. */
365 #if @GNULIB_LDEXPL@ && @REPLACE_LDEXPL@
366 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
367 # define ldexpl rpl_ldexpl
369 _GL_FUNCDECL_RPL (ldexpl, long double, (long double x, int exp));
370 _GL_CXXALIAS_RPL (ldexpl, long double, (long double x, int exp));
372 # if !@HAVE_DECL_LDEXPL@
373 _GL_FUNCDECL_SYS (ldexpl, long double, (long double x, int exp));
376 _GL_CXXALIAS_SYS (ldexpl, long double, (long double x, int exp));
380 _GL_CXXALIASWARN (ldexpl);
382 #if !@GNULIB_LDEXPL@ && defined GNULIB_POSIXCHECK
384 # if HAVE_RAW_DECL_LDEXPL
385 _GL_WARN_ON_USE (ldexpl, "ldexpl is unportable - "
386 "use gnulib module ldexpl for portability");
392 # if !@HAVE_LOGL@ || !@HAVE_DECL_LOGL@
393 _GL_FUNCDECL_SYS (logl, long double, (long double x));
395 _GL_CXXALIAS_SYS (logl, long double, (long double x));
396 _GL_CXXALIASWARN (logl);
397 #elif defined GNULIB_POSIXCHECK
399 # if HAVE_RAW_DECL_LOGL
400 _GL_WARN_ON_USE (logl, "logl is unportable - "
401 "use gnulib module mathl for portability");
407 # if @REPLACE_ROUNDF@
408 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
410 # define roundf rpl_roundf
412 _GL_FUNCDECL_RPL (roundf, float, (float x));
413 _GL_CXXALIAS_RPL (roundf, float, (float x));
415 # if !@HAVE_DECL_ROUNDF@
416 _GL_FUNCDECL_SYS (roundf, float, (float x));
418 _GL_CXXALIAS_SYS (roundf, float, (float x));
420 _GL_CXXALIASWARN (roundf);
421 #elif defined GNULIB_POSIXCHECK
423 # if HAVE_RAW_DECL_ROUNDF
424 _GL_WARN_ON_USE (roundf, "roundf is unportable - "
425 "use gnulib module roundf for portability");
431 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
433 # define round rpl_round
435 _GL_FUNCDECL_RPL (round, double, (double x));
436 _GL_CXXALIAS_RPL (round, double, (double x));
438 # if !@HAVE_DECL_ROUND@
439 _GL_FUNCDECL_SYS (round, double, (double x));
441 _GL_CXXALIAS_SYS (round, double, (double x));
443 _GL_CXXALIASWARN (round);
444 #elif defined GNULIB_POSIXCHECK
446 # if HAVE_RAW_DECL_ROUND
447 _GL_WARN_ON_USE (round, "round is unportable - "
448 "use gnulib module round for portability");
453 # if @REPLACE_ROUNDL@
454 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
456 # define roundl rpl_roundl
458 _GL_FUNCDECL_RPL (roundl, long double, (long double x));
459 _GL_CXXALIAS_RPL (roundl, long double, (long double x));
461 # if !@HAVE_DECL_ROUNDL@
462 _GL_FUNCDECL_SYS (roundl, long double, (long double x));
464 _GL_CXXALIAS_SYS (roundl, long double, (long double x));
466 _GL_CXXALIASWARN (roundl);
467 #elif defined GNULIB_POSIXCHECK
469 # if HAVE_RAW_DECL_ROUNDL
470 _GL_WARN_ON_USE (roundl, "roundl is unportable - "
471 "use gnulib module roundl for portability");
477 # if !@HAVE_SINL@ || !@HAVE_DECL_SINL@
478 _GL_FUNCDECL_SYS (sinl, long double, (long double x));
480 _GL_CXXALIAS_SYS (sinl, long double, (long double x));
481 _GL_CXXALIASWARN (sinl);
482 #elif defined GNULIB_POSIXCHECK
484 # if HAVE_RAW_DECL_SINL
485 _GL_WARN_ON_USE (sinl, "sinl is unportable - "
486 "use gnulib module mathl for portability");
492 # if !@HAVE_SQRTL@ || !@HAVE_DECL_SQRTL@
493 _GL_FUNCDECL_SYS (sqrtl, long double, (long double x));
495 _GL_CXXALIAS_SYS (sqrtl, long double, (long double x));
496 _GL_CXXALIASWARN (sqrtl);
497 #elif defined GNULIB_POSIXCHECK
499 # if HAVE_RAW_DECL_SQRTL
500 _GL_WARN_ON_USE (sqrtl, "sqrtl is unportable - "
501 "use gnulib module mathl for portability");
507 # if !@HAVE_TANL@ || !@HAVE_DECL_TANL@
508 _GL_FUNCDECL_SYS (tanl, long double, (long double x));
510 _GL_CXXALIAS_SYS (tanl, long double, (long double x));
511 _GL_CXXALIASWARN (tanl);
512 #elif defined GNULIB_POSIXCHECK
514 # if HAVE_RAW_DECL_TANL
515 _GL_WARN_ON_USE (tanl, "tanl is unportable - "
516 "use gnulib module mathl for portability");
522 # if @REPLACE_TRUNCF@
523 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
524 # define truncf rpl_truncf
526 _GL_FUNCDECL_RPL (truncf, float, (float x));
527 _GL_CXXALIAS_RPL (truncf, float, (float x));
529 # if !@HAVE_DECL_TRUNCF@
530 _GL_FUNCDECL_SYS (truncf, float, (float x));
532 _GL_CXXALIAS_SYS (truncf, float, (float x));
534 _GL_CXXALIASWARN (truncf);
535 #elif defined GNULIB_POSIXCHECK
537 # if HAVE_RAW_DECL_TRUNCF
538 _GL_WARN_ON_USE (truncf, "truncf is unportable - "
539 "use gnulib module truncf for portability");
545 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
546 # define trunc rpl_trunc
548 _GL_FUNCDECL_RPL (trunc, double, (double x));
549 _GL_CXXALIAS_RPL (trunc, double, (double x));
551 # if !@HAVE_DECL_TRUNC@
552 _GL_FUNCDECL_SYS (trunc, double, (double x));
554 _GL_CXXALIAS_SYS (trunc, double, (double x));
556 _GL_CXXALIASWARN (trunc);
557 #elif defined GNULIB_POSIXCHECK
559 # if HAVE_RAW_DECL_TRUNC
560 _GL_WARN_ON_USE (trunc, "trunc is unportable - "
561 "use gnulib module trunc for portability");
566 # if @REPLACE_TRUNCL@
567 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
569 # define truncl rpl_truncl
571 _GL_FUNCDECL_RPL (truncl, long double, (long double x));
572 _GL_CXXALIAS_RPL (truncl, long double, (long double x));
574 # if !@HAVE_DECL_TRUNCL@
575 _GL_FUNCDECL_SYS (truncl, long double, (long double x));
577 _GL_CXXALIAS_SYS (truncl, long double, (long double x));
579 _GL_CXXALIASWARN (truncl);
580 #elif defined GNULIB_POSIXCHECK
582 # if HAVE_RAW_DECL_TRUNCL
583 _GL_WARN_ON_USE (truncl, "truncl is unportable - "
584 "use gnulib module truncl for portability");
589 #if @GNULIB_ISFINITE@
590 # if @REPLACE_ISFINITE@
591 _GL_EXTERN_C int gl_isfinitef (float x);
592 _GL_EXTERN_C int gl_isfinited (double x);
593 _GL_EXTERN_C int gl_isfinitel (long double x);
595 # define isfinite(x) \
596 (sizeof (x) == sizeof (long double) ? gl_isfinitel (x) : \
597 sizeof (x) == sizeof (double) ? gl_isfinited (x) : \
600 #elif defined GNULIB_POSIXCHECK
601 # if defined isfinite
602 _GL_WARN_REAL_FLOATING_DECL (isfinite);
604 # define isfinite(x) _GL_WARN_REAL_FLOATING_IMPL (isfinite, x)
611 _GL_EXTERN_C int gl_isinff (float x);
612 _GL_EXTERN_C int gl_isinfd (double x);
613 _GL_EXTERN_C int gl_isinfl (long double x);
616 (sizeof (x) == sizeof (long double) ? gl_isinfl (x) : \
617 sizeof (x) == sizeof (double) ? gl_isinfd (x) : \
620 #elif defined GNULIB_POSIXCHECK
622 _GL_WARN_REAL_FLOATING_DECL (isinf);
624 # define isinf(x) _GL_WARN_REAL_FLOATING_IMPL (isinf, x)
630 /* Test for NaN for 'float' numbers. */
632 /* The original <math.h> included above provides a declaration of isnan macro
633 or (older) isnanf function. */
635 /* GCC 4.0 and newer provides three built-ins for isnan. */
637 # define isnanf(x) __builtin_isnanf ((float)(x))
640 # define isnanf(x) isnan ((float)(x))
643 /* Test whether X is a NaN. */
645 # define isnanf rpl_isnanf
646 _GL_EXTERN_C int isnanf (float x);
651 /* Test for NaN for 'double' numbers.
652 This function is a gnulib extension, unlike isnan() which applied only
653 to 'double' numbers earlier but now is a type-generic macro. */
655 /* The original <math.h> included above provides a declaration of isnan
658 /* GCC 4.0 and newer provides three built-ins for isnan. */
660 # define isnand(x) __builtin_isnan ((double)(x))
663 # define isnand(x) isnan ((double)(x))
666 /* Test whether X is a NaN. */
668 # define isnand rpl_isnand
669 _GL_EXTERN_C int isnand (double x);
674 /* Test for NaN for 'long double' numbers. */
676 /* The original <math.h> included above provides a declaration of isnan
677 macro or (older) isnanl function. */
679 /* GCC 4.0 and newer provides three built-ins for isnan. */
681 # define isnanl(x) __builtin_isnanl ((long double)(x))
684 # define isnanl(x) isnan ((long double)(x))
687 /* Test whether X is a NaN. */
689 # define isnanl rpl_isnanl
690 _GL_EXTERN_C int isnanl (long double x);
694 /* This must come *after* the snippets for GNULIB_ISNANF and GNULIB_ISNANL! */
697 /* We can't just use the isnanf macro (e.g.) as exposed by
698 isnanf.h (e.g.) here, because those may end up being macros
699 that recursively expand back to isnan. So use the gnulib
700 replacements for them directly. */
701 # if @HAVE_ISNANF@ && __GNUC__ >= 4
702 # define gl_isnan_f(x) __builtin_isnanf ((float)(x))
704 _GL_EXTERN_C int rpl_isnanf (float x);
705 # define gl_isnan_f(x) rpl_isnanf (x)
707 # if @HAVE_ISNAND@ && __GNUC__ >= 4
708 # define gl_isnan_d(x) __builtin_isnan ((double)(x))
710 _GL_EXTERN_C int rpl_isnand (double x);
711 # define gl_isnan_d(x) rpl_isnand (x)
713 # if @HAVE_ISNANL@ && __GNUC__ >= 4
714 # define gl_isnan_l(x) __builtin_isnanl ((long double)(x))
716 _GL_EXTERN_C int rpl_isnanl (long double x);
717 # define gl_isnan_l(x) rpl_isnanl (x)
721 (sizeof (x) == sizeof (long double) ? gl_isnan_l (x) : \
722 sizeof (x) == sizeof (double) ? gl_isnan_d (x) : \
727 (sizeof (x) == sizeof (long double) ? __builtin_isnanl ((long double)(x)) : \
728 sizeof (x) == sizeof (double) ? __builtin_isnan ((double)(x)) : \
729 __builtin_isnanf ((float)(x)))
731 /* Ensure isnan is a macro. */
735 #elif defined GNULIB_POSIXCHECK
737 _GL_WARN_REAL_FLOATING_DECL (isnan);
739 # define isnan(x) _GL_WARN_REAL_FLOATING_IMPL (isnan, x)
745 # if @REPLACE_SIGNBIT_USING_GCC@
747 /* GCC 4.0 and newer provides three built-ins for signbit. */
748 # define signbit(x) \
749 (sizeof (x) == sizeof (long double) ? __builtin_signbitl (x) : \
750 sizeof (x) == sizeof (double) ? __builtin_signbit (x) : \
751 __builtin_signbitf (x))
753 # if @REPLACE_SIGNBIT@
755 _GL_EXTERN_C int gl_signbitf (float arg);
756 _GL_EXTERN_C int gl_signbitd (double arg);
757 _GL_EXTERN_C int gl_signbitl (long double arg);
758 # if __GNUC__ >= 2 && !__STRICT_ANSI__
759 # define _GL_NUM_UINT_WORDS(type) \
760 ((sizeof (type) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
761 # if defined FLT_SIGNBIT_WORD && defined FLT_SIGNBIT_BIT && !defined gl_signbitf
762 # define gl_signbitf_OPTIMIZED_MACRO
763 # define gl_signbitf(arg) \
764 ({ union { float _value; \
765 unsigned int _word[_GL_NUM_UINT_WORDS (float)]; \
768 (_m._word[FLT_SIGNBIT_WORD] >> FLT_SIGNBIT_BIT) & 1; \
771 # if defined DBL_SIGNBIT_WORD && defined DBL_SIGNBIT_BIT && !defined gl_signbitd
772 # define gl_signbitd_OPTIMIZED_MACRO
773 # define gl_signbitd(arg) \
774 ({ union { double _value; \
775 unsigned int _word[_GL_NUM_UINT_WORDS (double)]; \
778 (_m._word[DBL_SIGNBIT_WORD] >> DBL_SIGNBIT_BIT) & 1; \
781 # if defined LDBL_SIGNBIT_WORD && defined LDBL_SIGNBIT_BIT && !defined gl_signbitl
782 # define gl_signbitl_OPTIMIZED_MACRO
783 # define gl_signbitl(arg) \
784 ({ union { long double _value; \
785 unsigned int _word[_GL_NUM_UINT_WORDS (long double)]; \
788 (_m._word[LDBL_SIGNBIT_WORD] >> LDBL_SIGNBIT_BIT) & 1; \
792 # define signbit(x) \
793 (sizeof (x) == sizeof (long double) ? gl_signbitl (x) : \
794 sizeof (x) == sizeof (double) ? gl_signbitd (x) : \
797 #elif defined GNULIB_POSIXCHECK
799 _GL_WARN_REAL_FLOATING_DECL (signbit);
801 # define signbit(x) _GL_WARN_REAL_FLOATING_IMPL (signbit, x)
806 #endif /* _GL_MATH_H */
807 #endif /* _GL_MATH_H */