# ceil.m4 serial 4
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.

AC_DEFUN([gl_FUNC_CEIL],
[
  dnl Test whether ceil() can be used without libm.
  gl_FUNC_CEIL_LIBS
  if test "$CEIL_LIBM" = "?"; then
    CEIL_LIBM=
  fi
  AC_SUBST([CEIL_LIBM])
])

# Determines the libraries needed to get the ceil() function.
# Sets CEIL_LIBM.
AC_DEFUN([gl_FUNC_CEIL_LIBS],
[
  gl_CACHE_VAL_SILENT([gl_cv_func_ceil_libm], [
    gl_cv_func_ceil_libm=?
    AC_LINK_IFELSE(
      [AC_LANG_PROGRAM(
         [[#ifndef __NO_MATH_INLINES
           # define __NO_MATH_INLINES 1 /* for glibc */
           #endif
           #include <math.h>
           double x;]],
         [[x = ceil(x);]])],
      [gl_cv_func_ceil_libm=])
    if test "$gl_cv_func_ceil_libm" = "?"; then
      save_LIBS="$LIBS"
      LIBS="$LIBS -lm"
      AC_LINK_IFELSE(
        [AC_LANG_PROGRAM(
           [[#ifndef __NO_MATH_INLINES
             # define __NO_MATH_INLINES 1 /* for glibc */
             #endif
             #include <math.h>
             double x;]],
           [[x = ceil(x);]])],
        [gl_cv_func_ceil_libm="-lm"])
      LIBS="$save_LIBS"
    fi
  ])
  CEIL_LIBM="$gl_cv_func_ceil_libm"
])