# printf-frexp.m4 serial 5

dnl Copyright (C) 2007, 2009-2018 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_REQUIRE([gl_CHECK_FREXP_NO_LIBM])

  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_LINK_IFELSE(

        [AC_LANG_PROGRAM(

           [[#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

])