| # sqrtf.m4 serial 3 |
| 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_SQRTF], |
| [ |
| AC_REQUIRE([gl_MATH_H_DEFAULTS]) |
| AC_REQUIRE([gl_FUNC_SQRT]) |
| |
| dnl Persuade glibc <math.h> to declare sqrtf(). |
| AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) |
| |
| dnl Test whether sqrtf() exists. Assume that sqrtf(), if it exists, is |
| dnl defined in the same library as sqrt(). |
| save_LIBS="$LIBS" |
| LIBS="$LIBS $SQRT_LIBM" |
| AC_CHECK_FUNCS([sqrtf]) |
| LIBS="$save_LIBS" |
| if test $ac_cv_func_sqrtf = yes; then |
| SQRTF_LIBM="$SQRT_LIBM" |
| else |
| HAVE_SQRTF=0 |
| dnl If the function is declared but does not appear to exist, it may be |
| dnl defined as an inline function. In order to avoid a conflict, we have |
| dnl to define rpl_sqrtf, not sqrtf. |
| AC_CHECK_DECLS([sqrtf], [REPLACE_SQRTF=1], , [[#include <math.h>]]) |
| SQRTF_LIBM="$SQRT_LIBM" |
| fi |
| AC_SUBST([SQRTF_LIBM]) |
| ]) |
