glibc/sysdeps/libm-ieee754/e_gamma_r.c
Ulrich Drepper 6796bc807a Update.
1998-09-06 09:53 -0400  Zack Weinberg  <zack@rabi.phys.columbia.edu>

	* Makeconfig (+gccwarn): Remove -Wno-parentheses.

	* elf/dl-open.c: Quiet -Wparentheses warnings.
	* iconvdata/johab.c: Likewise.
	* iconvdata/uhc.c: Likewise.
	* inet/inet_net.c: Likewise.
	* io/fts.c: Likewise.
	* locale/newlocale.c: Likewise.
	* misc/getttyent.c: Likewise.
	* misc/mntent_r.c: Likewise.
	* misc/ttyslot.c: Likewise.
	* nscd/nscd_conf.c: Likewise.
	* nss/nsswitch.c: Likewise.
	* resolv/gethnamaddr.c: Likewise.
	* resolv/nsap_addr.c: Likewise.
	* resolv/res_debug.c: Likewise.
	* stdio-common/_itoa.c: Likewise.
	* stdlib/strtod.c: Likewise.
	* string/strverscmp.c: Likewise.
	* sunrpc/svc.c: Likewise.
	* sysdeps/libm-ieee754/e_cosh.c: Likewise.
	* sysdeps/libm-ieee754/e_gamma_r.c: Likewise.
	* sysdeps/libm-ieee754/e_sinh.c: Likewise.
	* sysdeps/posix/getaddrinfo.c: Likewise.

	* include/dlfcn.h: Likewise.
	* elf/dlfcn.h: Declare dladdr only for __USE_GNU.
	Define RTLD_DEFAULT.
1998-09-06 23:45:24 +00:00

48 lines
1.7 KiB
C

/* Implementation of gamma function according to ISO C.
Copyright (C) 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <math.h>
#include <math_private.h>
double
__ieee754_gamma_r (double x, int *signgamp)
{
/* We don't have a real gamma implementation now. We'll use lgamma
and the exp function. But due to the required boundary
conditions we must check some values separately. */
int32_t hx;
u_int32_t lx;
EXTRACT_WORDS (hx, lx, x);
if (((hx & 0x7fffffff) | lx) == 0)
/* Return value for x == 0 is NaN with invalid exception. */
return x / x;
if (hx < 0 && (u_int32_t) hx < 0xfff00000 && __rint (x) == x)
{
/* Return value for integer x < 0 is NaN with invalid exception. */
return (x - x) / (x - x);
}
/* XXX FIXME. */
return __ieee754_exp (__ieee754_lgamma_r (x, signgamp));
}