1 /* A GNU-like <math.h>.
3 Copyright (C) 2002-2003, 2007-2010 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/>. */
19 @PRAGMA_SYSTEM_HEADER@
24 /* The include_next requires a split double-inclusion guard. */
25 #@INCLUDE_NEXT_AS_FIRST_DIRECTIVE@ @NEXT_AS_FIRST_DIRECTIVE_MATH_H@
31 /* The definitions of _GL_FUNCDECL_RPL etc. are copied here. */
33 /* The definition of _GL_ARG_NONNULL is copied here. */
35 /* The definition of _GL_WARN_ON_USE is copied here. */
37 /* Helper macros to define a portability warning for the
38 classification macro FUNC called with VALUE. POSIX declares the
39 classification macros with an argument of real-floating (that is,
40 one of float, double, or long double). */
41 #define _GL_WARN_REAL_FLOATING_DECL(func) \
43 rpl_ ## func ## f (float f) \
48 rpl_ ## func ## d (double d) \
53 rpl_ ## func ## l (long double l) \
57 _GL_WARN_ON_USE (rpl_ ## func ## f, #func " is unportable - " \
58 "use gnulib module " #func " for portability"); \
59 _GL_WARN_ON_USE (rpl_ ## func ## d, #func " is unportable - " \
60 "use gnulib module " #func " for portability"); \
61 _GL_WARN_ON_USE (rpl_ ## func ## l, #func " is unportable - " \
62 "use gnulib module " #func " for portability")
63 #define _GL_WARN_REAL_FLOATING_IMPL(func, value) \
64 (sizeof (value) == sizeof (float) ? rpl_ ## func ## f (value) \
65 : sizeof (value) == sizeof (double) ? rpl_ ## func ## d (value) \
66 : rpl_ ## func ## l (value))
69 /* POSIX allows platforms that don't support NAN. But all major
70 machines in the past 15 years have supported something close to
71 IEEE NaN, so we define this unconditionally. We also must define
72 it on platforms like Solaris 10, where NAN is present but defined
73 as a function pointer rather than a floating point constant. */
74 #if !defined NAN || @REPLACE_NAN@
76 /* The Compaq (ex-DEC) C 6.4 compiler chokes on the expression 0.0 / 0.0. */
81 static float zero = 0.0f;
86 # define NAN (0.0f / 0.0f)
90 /* Solaris 10 defines HUGE_VAL, but as a function pointer rather
91 than a floating point constant. */
92 #if @REPLACE_HUGE_VAL@
94 # define HUGE_VAL (1.0 / 0.0)
101 If x finite and nonzero: 0.5 <= |mantissa| < 1.0.
102 If x is zero: mantissa = x, exp = 0.
103 If x is infinite or NaN: mantissa = x, exp unspecified.
104 Store exp in *EXPPTR and return mantissa. */
107 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
108 # define frexp rpl_frexp
110 _GL_FUNCDECL_RPL (frexp, double, (double x, int *expptr) _GL_ARG_NONNULL ((2)));
111 _GL_CXXALIAS_RPL (frexp, double, (double x, int *expptr));
113 _GL_CXXALIAS_SYS (frexp, double, (double x, int *expptr));
115 _GL_CXXALIASWARN (frexp);
116 #elif defined GNULIB_POSIXCHECK
118 /* Assume frexp is always declared. */
119 _GL_WARN_ON_USE (frexp, "frexp is unportable - "
120 "use gnulib module frexp for portability");
125 # if !@HAVE_DECL_LOGB@
126 _GL_EXTERN_C double logb (double x);
128 #elif defined GNULIB_POSIXCHECK
130 # if HAVE_RAW_DECL_LOGB
131 _GL_WARN_ON_USE (logb, "logb is unportable - "
132 "use gnulib module logb for portability");
138 # if !@HAVE_ACOSL@ || !@HAVE_DECL_ACOSL@
139 _GL_FUNCDECL_SYS (acosl, long double, (long double x));
141 _GL_CXXALIAS_SYS (acosl, long double, (long double x));
142 _GL_CXXALIASWARN (acosl);
143 #elif defined GNULIB_POSIXCHECK
145 # if HAVE_RAW_DECL_ACOSL
146 _GL_WARN_ON_USE (acosl, "acosl is unportable - "
147 "use gnulib module mathl for portability");
153 # if !@HAVE_ASINL@ || !@HAVE_DECL_ASINL@
154 _GL_FUNCDECL_SYS (asinl, long double, (long double x));
156 _GL_CXXALIAS_SYS (asinl, long double, (long double x));
157 _GL_CXXALIASWARN (asinl);
158 #elif defined GNULIB_POSIXCHECK
160 # if HAVE_RAW_DECL_ASINL
161 _GL_WARN_ON_USE (asinl, "asinl is unportable - "
162 "use gnulib module mathl for portability");
168 # if !@HAVE_ATANL@ || !@HAVE_DECL_ATANL@
169 _GL_FUNCDECL_SYS (atanl, long double, (long double x));
171 _GL_CXXALIAS_SYS (atanl, long double, (long double x));
172 _GL_CXXALIASWARN (atanl);
173 #elif defined GNULIB_POSIXCHECK
175 # if HAVE_RAW_DECL_ATANL
176 _GL_WARN_ON_USE (atanl, "atanl is unportable - "
177 "use gnulib module mathl for portability");
184 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
185 # define ceilf rpl_ceilf
187 _GL_FUNCDECL_RPL (ceilf, float, (float x));
188 _GL_CXXALIAS_RPL (ceilf, float, (float x));
190 _GL_CXXALIAS_SYS (ceilf, float, (float x));
192 _GL_CXXALIASWARN (ceilf);
193 #elif defined GNULIB_POSIXCHECK
195 # if HAVE_RAW_DECL_CEILF
196 _GL_WARN_ON_USE (ceilf, "ceilf is unportable - "
197 "use gnulib module ceilf for portability");
203 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
204 # define ceill rpl_ceill
206 _GL_FUNCDECL_RPL (ceill, long double, (long double x));
207 _GL_CXXALIAS_RPL (ceill, long double, (long double x));
209 _GL_CXXALIAS_SYS (ceill, long double, (long double x));
211 _GL_CXXALIASWARN (ceill);
212 #elif defined GNULIB_POSIXCHECK
214 # if HAVE_RAW_DECL_CEILL
215 _GL_WARN_ON_USE (ceill, "ceill is unportable - "
216 "use gnulib module ceill for portability");
223 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
225 # define cosl rpl_cosl
227 _GL_FUNCDECL_RPL (cosl, long double, (long double x));
228 _GL_CXXALIAS_RPL (cosl, long double, (long double x));
230 # if !@HAVE_DECL_COSL@
231 _GL_FUNCDECL_SYS (cosl, long double, (long double x));
233 _GL_CXXALIAS_SYS (cosl, long double, (long double x));
235 _GL_CXXALIASWARN (cosl);
236 #elif defined GNULIB_POSIXCHECK
238 # if HAVE_RAW_DECL_COSL
239 _GL_WARN_ON_USE (cosl, "cosl is unportable - "
240 "use gnulib module mathl for portability");
246 # if !@HAVE_EXPL@ || !@HAVE_DECL_EXPL@
247 _GL_FUNCDECL_SYS (expl, long double, (long double x));
249 _GL_CXXALIAS_SYS (expl, long double, (long double x));
250 _GL_CXXALIASWARN (expl);
251 #elif defined GNULIB_POSIXCHECK
253 # if HAVE_RAW_DECL_EXPL
254 _GL_WARN_ON_USE (expl, "expl is unportable - "
255 "use gnulib module mathl for portability");
261 # if @REPLACE_FLOORF@
262 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
263 # define floorf rpl_floorf
265 _GL_FUNCDECL_RPL (floorf, float, (float x));
266 _GL_CXXALIAS_RPL (floorf, float, (float x));
268 _GL_CXXALIAS_SYS (floorf, float, (float x));
270 _GL_CXXALIASWARN (floorf);
271 #elif defined GNULIB_POSIXCHECK
273 # if HAVE_RAW_DECL_FLOORF
274 _GL_WARN_ON_USE (floorf, "floorf is unportable - "
275 "use gnulib module floorf for portability");
280 # if @REPLACE_FLOORL@
281 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
282 # define floorl rpl_floorl
284 _GL_FUNCDECL_RPL (floorl, long double, (long double x));
285 _GL_CXXALIAS_RPL (floorl, long double, (long double x));
287 _GL_CXXALIAS_SYS (floorl, long double, (long double x));
289 _GL_CXXALIASWARN (floorl);
290 #elif defined GNULIB_POSIXCHECK
292 # if HAVE_RAW_DECL_FLOORL
293 _GL_WARN_ON_USE (floorl, "floorl is unportable - "
294 "use gnulib module floorl for portability");
302 If x finite and nonzero: 0.5 <= |mantissa| < 1.0.
303 If x is zero: mantissa = x, exp = 0.
304 If x is infinite or NaN: mantissa = x, exp unspecified.
305 Store exp in *EXPPTR and return mantissa. */
306 #if @GNULIB_FREXPL@ && @REPLACE_FREXPL@
307 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
308 # define frexpl rpl_frexpl
310 _GL_FUNCDECL_RPL (frexpl, long double,
311 (long double x, int *expptr) _GL_ARG_NONNULL ((2)));
312 _GL_CXXALIAS_RPL (frexpl, long double, (long double x, int *expptr));
314 # if !@HAVE_DECL_FREXPL@
315 _GL_FUNCDECL_SYS (frexpl, long double,
316 (long double x, int *expptr) _GL_ARG_NONNULL ((2)));
319 _GL_CXXALIAS_SYS (frexpl, long double, (long double x, int *expptr));
323 _GL_CXXALIASWARN (frexpl);
325 #if !@GNULIB_FREXPL@ && defined GNULIB_POSIXCHECK
327 # if HAVE_RAW_DECL_FREXPL
328 _GL_WARN_ON_USE (frexpl, "frexpl is unportable - "
329 "use gnulib module frexpl for portability");
334 /* Return x * 2^exp. */
335 #if @GNULIB_LDEXPL@ && @REPLACE_LDEXPL@
336 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
337 # define ldexpl rpl_ldexpl
339 _GL_FUNCDECL_RPL (ldexpl, long double, (long double x, int exp));
340 _GL_CXXALIAS_RPL (ldexpl, long double, (long double x, int exp));
342 # if !@HAVE_DECL_LDEXPL@
343 _GL_FUNCDECL_SYS (ldexpl, long double, (long double x, int exp));
346 _GL_CXXALIAS_SYS (ldexpl, long double, (long double x, int exp));
350 _GL_CXXALIASWARN (ldexpl);
352 #if !@GNULIB_LDEXPL@ && defined GNULIB_POSIXCHECK
354 # if HAVE_RAW_DECL_LDEXPL
355 _GL_WARN_ON_USE (ldexpl, "ldexpl is unportable - "
356 "use gnulib module ldexpl for portability");
363 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
365 # define logl rpl_logl
367 _GL_FUNCDECL_RPL (logl, long double, (long double x));
368 _GL_CXXALIAS_RPL (logl, long double, (long double x));
370 # if !@HAVE_DECL_LOGL@
371 _GL_FUNCDECL_SYS (logl, long double, (long double x));
373 _GL_CXXALIAS_SYS (logl, long double, (long double x));
375 _GL_CXXALIASWARN (logl);
376 #elif defined GNULIB_POSIXCHECK
378 # if HAVE_RAW_DECL_LOGL
379 _GL_WARN_ON_USE (logl, "logl is unportable - "
380 "use gnulib module mathl for portability");
386 # if @REPLACE_ROUNDF@
387 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
389 # define roundf rpl_roundf
391 _GL_FUNCDECL_RPL (roundf, float, (float x));
392 _GL_CXXALIAS_RPL (roundf, float, (float x));
394 _GL_CXXALIAS_SYS (roundf, float, (float x));
396 _GL_CXXALIASWARN (roundf);
397 #elif defined GNULIB_POSIXCHECK
399 # if HAVE_RAW_DECL_ROUNDF
400 _GL_WARN_ON_USE (roundf, "roundf is unportable - "
401 "use gnulib module roundf for portability");
407 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
409 # define round rpl_round
411 _GL_FUNCDECL_RPL (round, double, (double x));
412 _GL_CXXALIAS_RPL (round, double, (double x));
414 _GL_CXXALIAS_SYS (round, double, (double x));
416 _GL_CXXALIASWARN (round);
417 #elif defined GNULIB_POSIXCHECK
419 # if HAVE_RAW_DECL_ROUND
420 _GL_WARN_ON_USE (round, "round is unportable - "
421 "use gnulib module round for portability");
426 # if @REPLACE_ROUNDL@
427 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
429 # define roundl rpl_roundl
431 _GL_FUNCDECL_RPL (roundl, long double, (long double x));
432 _GL_CXXALIAS_RPL (roundl, long double, (long double x));
434 _GL_CXXALIAS_SYS (roundl, long double, (long double x));
436 _GL_CXXALIASWARN (roundl);
437 #elif defined GNULIB_POSIXCHECK
439 # if HAVE_RAW_DECL_ROUNDL
440 _GL_WARN_ON_USE (roundl, "roundl is unportable - "
441 "use gnulib module roundl for portability");
448 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
450 # define sinl rpl_sinl
452 _GL_FUNCDECL_RPL (sinl, long double, (long double x));
453 _GL_CXXALIAS_RPL (sinl, long double, (long double x));
455 # if !@HAVE_DECL_SINL@
456 _GL_FUNCDECL_SYS (sinl, long double, (long double x));
458 _GL_CXXALIAS_SYS (sinl, long double, (long double x));
460 _GL_CXXALIASWARN (sinl);
461 #elif defined GNULIB_POSIXCHECK
463 # if HAVE_RAW_DECL_SINL
464 _GL_WARN_ON_USE (sinl, "sinl is unportable - "
465 "use gnulib module mathl for portability");
471 # if !@HAVE_SQRTL@ || !@HAVE_DECL_SQRTL@
472 _GL_FUNCDECL_SYS (sqrtl, long double, (long double x));
474 _GL_CXXALIAS_SYS (sqrtl, long double, (long double x));
475 _GL_CXXALIASWARN (sqrtl);
476 #elif defined GNULIB_POSIXCHECK
478 # if HAVE_RAW_DECL_SQRTL
479 _GL_WARN_ON_USE (sqrtl, "sqrtl is unportable - "
480 "use gnulib module mathl for portability");
486 # if !@HAVE_TANL@ || !@HAVE_DECL_TANL@
487 _GL_FUNCDECL_SYS (tanl, long double, (long double x));
489 _GL_CXXALIAS_SYS (tanl, long double, (long double x));
490 _GL_CXXALIASWARN (tanl);
491 #elif defined GNULIB_POSIXCHECK
493 # if HAVE_RAW_DECL_TANL
494 _GL_WARN_ON_USE (tanl, "tanl is unportable - "
495 "use gnulib module mathl for portability");
501 # if !@HAVE_DECL_TRUNCF@
502 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
503 # define truncf rpl_truncf
505 _GL_FUNCDECL_RPL (truncf, float, (float x));
506 _GL_CXXALIAS_RPL (truncf, float, (float x));
508 _GL_CXXALIAS_SYS (truncf, float, (float x));
510 _GL_CXXALIASWARN (truncf);
511 #elif defined GNULIB_POSIXCHECK
513 # if HAVE_RAW_DECL_TRUNCF
514 _GL_WARN_ON_USE (truncf, "truncf is unportable - "
515 "use gnulib module truncf for portability");
520 # if !@HAVE_DECL_TRUNC@
521 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
522 # define trunc rpl_trunc
524 _GL_FUNCDECL_RPL (trunc, double, (double x));
525 _GL_CXXALIAS_RPL (trunc, double, (double x));
527 _GL_CXXALIAS_SYS (trunc, double, (double x));
529 _GL_CXXALIASWARN (trunc);
530 #elif defined GNULIB_POSIXCHECK
532 # if HAVE_RAW_DECL_TRUNC
533 _GL_WARN_ON_USE (trunc, "trunc is unportable - "
534 "use gnulib module trunc for portability");
539 # if @REPLACE_TRUNCL@
540 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
542 # define truncl rpl_truncl
544 _GL_FUNCDECL_RPL (truncl, long double, (long double x));
545 _GL_CXXALIAS_RPL (truncl, long double, (long double x));
547 _GL_CXXALIAS_SYS (truncl, long double, (long double x));
549 _GL_CXXALIASWARN (truncl);
550 #elif defined GNULIB_POSIXCHECK
552 # if HAVE_RAW_DECL_TRUNCL
553 _GL_WARN_ON_USE (truncl, "truncl is unportable - "
554 "use gnulib module truncl for portability");
559 #if @GNULIB_ISFINITE@
560 # if @REPLACE_ISFINITE@
561 _GL_EXTERN_C int gl_isfinitef (float x);
562 _GL_EXTERN_C int gl_isfinited (double x);
563 _GL_EXTERN_C int gl_isfinitel (long double x);
565 # define isfinite(x) \
566 (sizeof (x) == sizeof (long double) ? gl_isfinitel (x) : \
567 sizeof (x) == sizeof (double) ? gl_isfinited (x) : \
570 #elif defined GNULIB_POSIXCHECK
571 # if defined isfinite
572 _GL_WARN_REAL_FLOATING_DECL (isfinite);
574 # define isfinite(x) _GL_WARN_REAL_FLOATING_IMPL (isfinite, x)
581 _GL_EXTERN_C int gl_isinff (float x);
582 _GL_EXTERN_C int gl_isinfd (double x);
583 _GL_EXTERN_C int gl_isinfl (long double x);
586 (sizeof (x) == sizeof (long double) ? gl_isinfl (x) : \
587 sizeof (x) == sizeof (double) ? gl_isinfd (x) : \
590 #elif defined GNULIB_POSIXCHECK
592 _GL_WARN_REAL_FLOATING_DECL (isinf);
594 # define isinf(x) _GL_WARN_REAL_FLOATING_IMPL (isinf, x)
600 /* Test for NaN for 'float' numbers. */
602 /* The original <math.h> included above provides a declaration of isnan macro
603 or (older) isnanf function. */
605 /* GCC 4.0 and newer provides three built-ins for isnan. */
607 # define isnanf(x) __builtin_isnanf ((float)(x))
610 # define isnanf(x) isnan ((float)(x))
613 /* Test whether X is a NaN. */
615 # define isnanf rpl_isnanf
616 _GL_EXTERN_C int isnanf (float x);
621 /* Test for NaN for 'double' numbers.
622 This function is a gnulib extension, unlike isnan() which applied only
623 to 'double' numbers earlier but now is a type-generic macro. */
625 /* The original <math.h> included above provides a declaration of isnan macro. */
627 /* GCC 4.0 and newer provides three built-ins for isnan. */
629 # define isnand(x) __builtin_isnan ((double)(x))
632 # define isnand(x) isnan ((double)(x))
635 /* Test whether X is a NaN. */
637 # define isnand rpl_isnand
638 _GL_EXTERN_C int isnand (double x);
643 /* Test for NaN for 'long double' numbers. */
645 /* The original <math.h> included above provides a declaration of isnan macro or (older) isnanl function. */
647 /* GCC 4.0 and newer provides three built-ins for isnan. */
649 # define isnanl(x) __builtin_isnanl ((long double)(x))
652 # define isnanl(x) isnan ((long double)(x))
655 /* Test whether X is a NaN. */
657 # define isnanl rpl_isnanl
658 _GL_EXTERN_C int isnanl (long double x);
662 /* This must come *after* the snippets for GNULIB_ISNANF and GNULIB_ISNANL! */
665 /* We can't just use the isnanf macro (e.g.) as exposed by
666 isnanf.h (e.g.) here, because those may end up being macros
667 that recursively expand back to isnan. So use the gnulib
668 replacements for them directly. */
669 # if @HAVE_ISNANF@ && __GNUC__ >= 4
670 # define gl_isnan_f(x) __builtin_isnan ((float)(x))
672 _GL_EXTERN_C int rpl_isnanf (float x);
673 # define gl_isnan_f(x) rpl_isnanf (x)
675 # if @HAVE_ISNAND@ && __GNUC__ >= 4
676 # define gl_isnan_d(x) __builtin_isnan ((double)(x))
678 _GL_EXTERN_C int rpl_isnand (double x);
679 # define gl_isnan_d(x) rpl_isnand (x)
681 # if @HAVE_ISNANL@ && __GNUC__ >= 4
682 # define gl_isnan_l(x) __builtin_isnan ((long double)(x))
684 _GL_EXTERN_C int rpl_isnanl (long double x);
685 # define gl_isnan_l(x) rpl_isnanl (x)
689 (sizeof (x) == sizeof (long double) ? gl_isnan_l (x) : \
690 sizeof (x) == sizeof (double) ? gl_isnan_d (x) : \
693 #elif defined GNULIB_POSIXCHECK
695 _GL_WARN_REAL_FLOATING_DECL (isnan);
697 # define isnan(x) _GL_WARN_REAL_FLOATING_IMPL (isnan, x)
703 # if @REPLACE_SIGNBIT_USING_GCC@
705 /* GCC 4.0 and newer provides three built-ins for signbit. */
706 # define signbit(x) \
707 (sizeof (x) == sizeof (long double) ? __builtin_signbitl (x) : \
708 sizeof (x) == sizeof (double) ? __builtin_signbit (x) : \
709 __builtin_signbitf (x))
711 # if @REPLACE_SIGNBIT@
713 _GL_EXTERN_C int gl_signbitf (float arg);
714 _GL_EXTERN_C int gl_signbitd (double arg);
715 _GL_EXTERN_C int gl_signbitl (long double arg);
716 # if __GNUC__ >= 2 && !__STRICT_ANSI__
717 # if defined FLT_SIGNBIT_WORD && defined FLT_SIGNBIT_BIT && !defined gl_signbitf
718 # define gl_signbitf_OPTIMIZED_MACRO
719 # define gl_signbitf(arg) \
720 ({ union { float _value; \
721 unsigned int _word[(sizeof (float) + sizeof (unsigned int) - 1) / sizeof (unsigned int)]; \
724 (_m._word[FLT_SIGNBIT_WORD] >> FLT_SIGNBIT_BIT) & 1; \
727 # if defined DBL_SIGNBIT_WORD && defined DBL_SIGNBIT_BIT && !defined gl_signbitd
728 # define gl_signbitd_OPTIMIZED_MACRO
729 # define gl_signbitd(arg) \
730 ({ union { double _value; \
731 unsigned int _word[(sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int)]; \
734 (_m._word[DBL_SIGNBIT_WORD] >> DBL_SIGNBIT_BIT) & 1; \
737 # if defined LDBL_SIGNBIT_WORD && defined LDBL_SIGNBIT_BIT && !defined gl_signbitl
738 # define gl_signbitl_OPTIMIZED_MACRO
739 # define gl_signbitl(arg) \
740 ({ union { long double _value; \
741 unsigned int _word[(sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int)]; \
744 (_m._word[LDBL_SIGNBIT_WORD] >> LDBL_SIGNBIT_BIT) & 1; \
748 # define signbit(x) \
749 (sizeof (x) == sizeof (long double) ? gl_signbitl (x) : \
750 sizeof (x) == sizeof (double) ? gl_signbitd (x) : \
753 #elif defined GNULIB_POSIXCHECK
755 _GL_WARN_REAL_FLOATING_DECL (signbit);
757 # define signbit(x) _GL_WARN_REAL_FLOATING_IMPL (signbit, x)
762 #endif /* _GL_MATH_H */
763 #endif /* _GL_MATH_H */