3 dnl Copyright (C) 2011-2024 Free Software Foundation, Inc.
4 dnl This file is free software; the Free Software Foundation
5 dnl gives unlimited permission to copy and/or distribute it,
6 dnl with or without modifications, as long as this notice is preserved.
8 AC_DEFUN([gl_FUNC_ACOSF],
10 AC_REQUIRE([gl_MATH_H_DEFAULTS])
11 AC_REQUIRE([gl_FUNC_ACOS])
13 dnl Persuade glibc <math.h> to declare acosf().
14 AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
16 dnl Test whether acosf() exists. Assume that acosf(), if it exists, is
17 dnl defined in the same library as acos().
19 LIBS="$LIBS $ACOS_LIBM"
20 AC_CHECK_FUNCS([acosf])
22 if test $ac_cv_func_acosf = yes; then
23 ACOSF_LIBM="$ACOS_LIBM"
26 dnl If the function is declared but does not appear to exist, it may be
27 dnl defined as an inline function. In order to avoid a conflict, we have
28 dnl to define rpl_acosf, not acosf.
29 AC_CHECK_DECLS([acosf], [REPLACE_ACOSF=1], , [[#include <math.h>]])
30 ACOSF_LIBM="$ACOS_LIBM"
32 AC_SUBST([ACOSF_LIBM])