# ===========================================================================

# http://www.gnu.org/software/autoconf-archive/ax_check_compiler_flags.html

# ===========================================================================

#

# SYNOPSIS

#

# AX_CHECK_COMPILER_FLAGS(FLAGS, [ACTION-SUCCESS], [ACTION-FAILURE])

#

# DESCRIPTION

#

# Check whether the given compiler FLAGS work with the current language's

# compiler, or whether they give an error. (Warnings, however, are

# ignored.)

#

# ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on

# success/failure.

#

# LICENSE

#

# Copyright (c) 2009 Steven G. Johnson <stevenj@alum.mit.edu>

# Copyright (c) 2009 Matteo Frigo

#

# This program is free software: you can redistribute it and/or modify it

# under the terms of the GNU General Public License as published by the

# Free Software Foundation, either version 3 of the License, or (at your

# option) any later version.

#

# This program is distributed in the hope that it will be useful, but

# WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General

# Public License for more details.

#

# You should have received a copy of the GNU General Public License along

# with this program. If not, see <http://www.gnu.org/licenses/>.

#

# As a special exception, the respective Autoconf Macro's copyright owner

# gives unlimited permission to copy, distribute and modify the configure

# scripts that are the output of Autoconf when processing the Macro. You

# need not follow the terms of the GNU General Public License when using

# or distributing such scripts, even though portions of the text of the

# Macro appear in them. The GNU General Public License (GPL) does govern

# all other use of the material that constitutes the Autoconf Macro.

#

# This special exception to the GPL applies to versions of the Autoconf

# Macro released by the Autoconf Archive. When you make and distribute a

# modified version of the Autoconf Macro, you may extend this special

# exception to the GPL to apply to your modified version as well.

#serial 9

AC_DEFUN([AX_CHECK_COMPILER_FLAGS],

[AC_PREREQ(2.59) dnl for _AC_LANG_PREFIX

AC_MSG_CHECKING([whether _AC_LANG compiler accepts $1])

dnl Some hackery here since AC_CACHE_VAL can't handle a non-literal varname:

AS_LITERAL_IF([$1],

[AC_CACHE_VAL(AS_TR_SH(ax_cv_[]_AC_LANG_ABBREV[]_flags_[$1]), [

ax_save_FLAGS=$[]_AC_LANG_PREFIX[]FLAGS

_AC_LANG_PREFIX[]FLAGS="$1"

AC_COMPILE_IFELSE([AC_LANG_PROGRAM()],

AS_TR_SH(ax_cv_[]_AC_LANG_ABBREV[]_flags_[$1])=yes,

AS_TR_SH(ax_cv_[]_AC_LANG_ABBREV[]_flags_[$1])=no)

_AC_LANG_PREFIX[]FLAGS=$ax_save_FLAGS])],

[ax_save_FLAGS=$[]_AC_LANG_PREFIX[]FLAGS

_AC_LANG_PREFIX[]FLAGS="$1"

AC_COMPILE_IFELSE([AC_LANG_PROGRAM()],

eval AS_TR_SH(ax_cv_[]_AC_LANG_ABBREV[]_flags_[$1])=yes,

eval AS_TR_SH(ax_cv_[]_AC_LANG_ABBREV[]_flags_[$1])=no)

_AC_LANG_PREFIX[]FLAGS=$ax_save_FLAGS])

eval ax_check_compiler_flags=$AS_TR_SH(ax_cv_[]_AC_LANG_ABBREV[]_flags_[$1])

AC_MSG_RESULT($ax_check_compiler_flags)

if test "x$ax_check_compiler_flags" = xyes; then

m4_default([$2], :)

else

m4_default([$3], :)

fi

])dnl AX_CHECK_COMPILER_FLAGS