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# printf-frexp.m4 serial 3
dnl Copyright (C) 2007, 2009, 2010 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.

dnl Check how to define printf_frexp() without linking with libm.

AC_DEFUN([gl_FUNC_PRINTF_FREXP],
[
  AC_CACHE_CHECK([whether frexp can be used without linking with libm],
    [gl_cv_func_frexp_no_libm],
    [
      AC_TRY_LINK([#include <math.h>
                   double x;
                   int y;],
                  [return frexp (x, &y) < 1;],
        [gl_cv_func_frexp_no_libm=yes],
        [gl_cv_func_frexp_no_libm=no])
    ])
  if test $gl_cv_func_frexp_no_libm = yes; then
    gl_FUNC_FREXP_WORKS
    case "$gl_cv_func_frexp_works" in
      *yes)
        AC_DEFINE([HAVE_FREXP_IN_LIBC], [1],
          [Define if the frexp function is available in libc.])
        ;;
    esac
  fi

  AC_CACHE_CHECK([whether ldexp can be used without linking with libm],
    [gl_cv_func_ldexp_no_libm],
    [
      AC_TRY_LINK([#include <math.h>
                   double x;
                   int y;],
                  [return ldexp (x, y) < 1;],
        [gl_cv_func_ldexp_no_libm=yes],
        [gl_cv_func_ldexp_no_libm=no])
    ])
  if test $gl_cv_func_ldexp_no_libm = yes; then
    AC_DEFINE([HAVE_LDEXP_IN_LIBC], [1],
      [Define if the ldexp function is available in libc.])
  fi
])