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Diffstat (limited to 'm4/ax_cflags_gcc_option.m4')
-rw-r--r-- | m4/ax_cflags_gcc_option.m4 | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/m4/ax_cflags_gcc_option.m4 b/m4/ax_cflags_gcc_option.m4 new file mode 100644 index 0000000..ae0d6da --- /dev/null +++ b/m4/ax_cflags_gcc_option.m4 @@ -0,0 +1,111 @@ +# =========================================================================== +# http://autoconf-archive.cryp.to/ax_cflags_gcc_option.html +# =========================================================================== +# +# SYNOPSIS +# +# AX_CFLAGS_GCC_OPTION (optionflag [,[shellvar][,[A][,[NA]]]) +# +# DESCRIPTION +# +# AX_CFLAGS_GCC_OPTION(-fvomit-frame) would show a message as like +# "checking CFLAGS for gcc -fvomit-frame ... yes" and adds the optionflag +# to CFLAGS if it is understood. You can override the shellvar-default of +# CFLAGS of course. The order of arguments stems from the explicit macros +# like AX_CFLAGS_WARN_ALL. +# +# The cousin AX_CXXFLAGS_GCC_OPTION would check for an option to add to +# CXXFLAGS - and it uses the autoconf setup for C++ instead of C (since it +# is possible to use different compilers for C and C++). +# +# The macro is a lot simpler than any special AX_CFLAGS_* macro (or +# ac_cxx_rtti.m4 macro) but allows to check for arbitrary options. +# However, if you use this macro in a few places, it would be great if you +# would make up a new function-macro and submit it to the ac-archive. +# +# - $1 option-to-check-for : required ("-option" as non-value) +# - $2 shell-variable-to-add-to : CFLAGS (or CXXFLAGS in the other case) +# - $3 action-if-found : add value to shellvariable +# - $4 action-if-not-found : nothing +# +# There are other variants that emerged from the original macro variant +# which did just test an option to be possibly added. However, some +# compilers accept an option silently, or possibly for just another option +# that was not intended. Therefore, we have to do a generic test for a +# compiler family. For gcc we check "-pedantic" being accepted which is +# also understood by compilers who just want to be compatible with gcc +# even when not being made from gcc sources. +# +# This version has been modified by Vincent Bernat <bernat@luffy.cx> +# to ensure that the shell variable the option is added to is +# prepended to the test variable (like a regular CFLAGS). +# +# See also: AX_CFLAGS_SUN_OPTION, AX_CFLAGS_HPUX_OPTION, +# AX_CFLAGS_AIX_OPTION, and AX_CFLAGS_IRIX_OPTION. +# +# LICENSE +# +# Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de> +# +# 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 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. + +dnl ------------------------------------------------------------------------- + +AC_DEFUN([AX_CFLAGS_GCC_OPTION], [dnl +AS_VAR_PUSHDEF([FLAGS],[CFLAGS])dnl +AS_VAR_PUSHDEF([VAR],[ac_cv_cflags_gcc_option_$1])dnl +AC_CACHE_CHECK([FLAGS for gcc m4_ifval($1,$1,-option)], +VAR,[AS_VAR_SET([VAR],["no, unknown"]) + AC_LANG_SAVE + AC_LANG([C]) + ac_save_[]FLAGS="$[]FLAGS" +for ac_arg dnl +in "-pedantic -Werror % m4_ifval($1,$1,-option)" dnl GCC + "-pedantic % m4_ifval($1,$1,-option) %% no, obsolete" dnl new GCC + # +do FLAGS="$ac_save_[]FLAGS $[]m4_ifval($2,$2,) "`echo $ac_arg | sed -e 's,%%.*,,' -e 's,%,,'` + AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[return 0;]])], + [AS_VAR_SET([VAR],[`echo $ac_arg | sed -e 's,.*% *,,'`]) ; break], + []) +done + FLAGS="$ac_save_[]FLAGS" + AC_LANG_RESTORE +]) +AS_VAR_COPY([ac_res], [VAR]) +case ".${ac_res}" in + .ok|.ok,*) m4_ifvaln($3,$3) ;; + .|.no|.no,*) m4_ifvaln($4,$4) ;; + *) m4_ifvaln($3,$3,[ + if echo " $[]m4_ifval($2,$2,FLAGS) " | grep " ${ac_res} " 2>&1 >/dev/null + then AC_RUN_LOG([: m4_ifval($2,$2,FLAGS) does contain ${ac_res}]) + else AC_RUN_LOG([: m4_ifval($2,$2,FLAGS)="$m4_ifval($2,$2,FLAGS) ${ac_res}"]) + m4_ifval($2,$2,FLAGS)="$m4_ifval($2,$2,FLAGS) ${ac_res}" + fi ]) ;; +esac +AS_VAR_POPDEF([VAR])dnl +AS_VAR_POPDEF([FLAGS])dnl +]) |