2 dnl Copyright (C) 2010 Free Software Foundation, Inc.
3 dnl This file is free software; the Free Software Foundation
4 dnl gives unlimited permission to copy and/or distribute it,
5 dnl with or without modifications, as long as this notice is preserved.
7 AC_DEFUN([gl_FUNC_SQRTL],
9 AC_REQUIRE([gl_MATH_H_DEFAULTS])
10 dnl Persuade glibc <math.h> to declare sqrtl().
11 AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
14 AC_CACHE_CHECK([whether sqrtl() can be used without linking with libm],
15 [gl_cv_func_sqrtl_no_libm],
17 AC_TRY_LINK([#ifndef __NO_MATH_INLINES
18 # define __NO_MATH_INLINES 1 /* for glibc */
22 [return sqrtl (x) > 0.4;],
23 [gl_cv_func_sqrtl_no_libm=yes],
24 [gl_cv_func_sqrtl_no_libm=no])
26 if test $gl_cv_func_sqrtl_no_libm = no; then
27 AC_CACHE_CHECK([whether sqrtl() can be used with libm],
28 [gl_cv_func_sqrtl_in_libm],
32 AC_TRY_LINK([#ifndef __NO_MATH_INLINES
33 # define __NO_MATH_INLINES 1 /* for glibc */
37 [return sqrtl (x) > 0.4;],
38 [gl_cv_func_sqrtl_in_libm=yes],
39 [gl_cv_func_sqrtl_in_libm=no])
42 if test $gl_cv_func_sqrtl_in_libm = yes; then
46 if test $gl_cv_func_sqrtl_no_libm = yes \
47 || test $gl_cv_func_sqrtl_in_libm = yes; then
48 dnl Also check whether it's declared.
49 dnl MacOS X 10.3 has sqrtl() in libc but doesn't declare it in <math.h>.
50 AC_CHECK_DECL([sqrtl], , [HAVE_DECL_SQRTL=0], [#include <math.h>])
55 AC_REQUIRE([gl_FUNC_ISNANL])
56 AC_REQUIRE([gl_FUNC_FREXPL])
57 AC_REQUIRE([gl_FUNC_LDEXPL])
58 AC_REQUIRE([gl_FUNC_SQRT])
59 SQRTL_LIBM="$ISNANL_LIBM $FREXPL_LIBM $LDEXPL_LIBM $SQRT_LIBM"
61 AC_SUBST([SQRTL_LIBM])