| # copysignf.m4 serial 4 |
| dnl Copyright (C) 2011-2020 Free Software Foundation, Inc. |
| dnl This file is free software; the Free Software Foundation |
| dnl gives unlimited permission to copy and/or distribute it, |
| dnl with or without modifications, as long as this notice is preserved. |
| |
| AC_DEFUN([gl_FUNC_COPYSIGNF], |
| [ |
| AC_REQUIRE([gl_MATH_H_DEFAULTS]) |
| AC_REQUIRE([AC_CANONICAL_HOST]) |
| |
| dnl Persuade glibc <math.h> to declare copysignf(). |
| AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) |
| |
| dnl Determine COPYSIGNF_LIBM. |
| gl_MATHFUNC([copysignf], [float], [(float, float)], |
| [extern |
| #ifdef __cplusplus |
| "C" |
| #endif |
| float copysignf (float, float); |
| ]) |
| if test $gl_cv_func_copysignf_no_libm = yes \ |
| || test $gl_cv_func_copysignf_in_libm = yes; then |
| HAVE_COPYSIGNF=1 |
| dnl Also check whether it's declared. |
| dnl IRIX 6.5 has copysignf() in libm but doesn't declare it in <math.h>. |
| AC_CHECK_DECL([copysignf], , [HAVE_DECL_COPYSIGNF=0], [[#include <math.h>]]) |
| else |
| HAVE_COPYSIGNF=0 |
| HAVE_DECL_COPYSIGNF=0 |
| dnl On HP-UX 11.31/ia64, cc has a built-in for copysignf that redirects |
| dnl to the symbol '_copysignf', defined in libm, not libc. |
| case "$host_os" in |
| hpux*) COPYSIGNF_LIBM='-lm' ;; |
| *) COPYSIGNF_LIBM= ;; |
| esac |
| fi |
| AC_SUBST([COPYSIGNF_LIBM]) |
| ]) |
