1 # printf-frexp.m4 serial 3
2 dnl Copyright (C) 2007, 2009, 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 dnl Check how to define printf_frexp() without linking with libm.
9 AC_DEFUN([gl_FUNC_PRINTF_FREXP],
11 AC_CACHE_CHECK([whether frexp can be used without linking with libm],
12 [gl_cv_func_frexp_no_libm],
14 AC_TRY_LINK([#include <math.h>
17 [return frexp (x, &y) < 1;],
18 [gl_cv_func_frexp_no_libm=yes],
19 [gl_cv_func_frexp_no_libm=no])
21 if test $gl_cv_func_frexp_no_libm = yes; then
23 case "$gl_cv_func_frexp_works" in
25 AC_DEFINE([HAVE_FREXP_IN_LIBC], [1],
26 [Define if the frexp function is available in libc.])
31 AC_CACHE_CHECK([whether ldexp can be used without linking with libm],
32 [gl_cv_func_ldexp_no_libm],
34 AC_TRY_LINK([#include <math.h>
37 [return ldexp (x, y) < 1;],
38 [gl_cv_func_ldexp_no_libm=yes],
39 [gl_cv_func_ldexp_no_libm=no])
41 if test $gl_cv_func_ldexp_no_libm = yes; then
42 AC_DEFINE([HAVE_LDEXP_IN_LIBC], [1],
43 [Define if the ldexp function is available in libc.])