wxWidgets/build/aclocal/ax_gcc_option.m4

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# ===========================================================================
# http://autoconf-archive.cryp.to/ax_gcc_option.html
# ===========================================================================
#
# SYNOPSIS
#
# AX_GCC_OPTION(OPTION,EXTRA-OPTIONS,TEST-PROGRAM,ACTION-IF-SUCCESSFUL,ACTION-IF-NOT-SUCCESFUL)
#
# DESCRIPTION
#
# AX_GCC_OPTION checks wheter gcc accepts the passed OPTION. If it accepts
# the OPTION then ACTION-IF-SUCCESSFUL will be executed, otherwise
# ACTION-IF-UNSUCCESSFUL.
#
# NOTE: This macro will be obsoleted by AX_C_CHECK_FLAG AX_CXX_CHECK_FLAG,
# AX_CPP_CHECK_FLAG, AX_CXXCPP_CHECK_FLAG and AX_LD_CHECK_FLAG.
#
# A typical usage should be the following one:
#
# AX_GCC_OPTION([-fomit-frame-pointer],[],[],[
# AC_MSG_NOTICE([The option is supported])],[
# AC_MSG_NOTICE([No luck this time])
# ])
#
# The macro doesn't discriminate between languages so, if you are testing
# for an option that works for C++ but not for C you should use '-x c++'
# as EXTRA-OPTIONS:
#
# AX_GCC_OPTION([-fno-rtti],[-x c++],[],[ ... ],[ ... ])
#
# OPTION is tested against the following code:
#
# int main()
# {
# return 0;
# }
#
# The optional TEST-PROGRAM comes handy when the default main() is not
# suited for the option being checked
#
# So, if you need to test for -fstrict-prototypes option you should
# probably use the macro as follows:
#
# AX_GCC_OPTION([-fstrict-prototypes],[-x c++],[
# int main(int argc, char ** argv)
# {
# (void) argc;
# (void) argv;
#
# return 0;
# }
# ],[ ... ],[ ... ])
#
# Note that the macro compiles but doesn't link the test program so it is
# not suited for checking options that are passed to the linker, like:
#
# -Wl,-L<a-library-path>
#
# In order to avoid such kind of problems you should think about usinguse
# the AX_*_CHECK_FLAG family macros
#
# LAST MODIFICATION
#
# 2008-04-12
#
# COPYLEFT
#
# Copyright (c) 2008 Francesco Salvestrini <salvestrini@users.sourceforge.net>
# Copyright (c) 2008 Bogdan Drozdowski <bogdandr@op.pl>
#
# 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 2 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 Macro 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.
AC_DEFUN([AX_GCC_OPTION], [
AC_REQUIRE([AC_PROG_CC])
AC_MSG_CHECKING([if gcc accepts $1 option])
AS_IF([ test "x$GCC" = "xyes" ],[
AS_IF([ test -z "$3" ],[
ax_gcc_option_test="int main()
{
return 0;
}"
],[
ax_gcc_option_test="$3"
])
# Dump the test program to file
cat <<EOF > conftest.c
$ax_gcc_option_test
EOF
# Dump back the file to the log, useful for debugging purposes
AC_TRY_COMMAND(cat conftest.c 1>&AS_MESSAGE_LOG_FD)
AS_IF([ AC_TRY_COMMAND($CC $2 $1 -c conftest.c 1>&AS_MESSAGE_LOG_FD) ],[
AC_MSG_RESULT([yes])
$4
],[
AC_MSG_RESULT([no])
$5
])
],[
AC_MSG_RESULT([no gcc available])
])
])