1 # ===========================================================================
2 # http://autoconf-archive.cryp.to/ax_cflags_gcc_option.html
3 # ===========================================================================
7 # AX_CFLAGS_GCC_OPTION (optionflag [,[shellvar][,[A][,[NA]]])
11 # AX_CFLAGS_GCC_OPTION(-fvomit-frame) would show a message as like
12 # "checking CFLAGS for gcc -fvomit-frame ... yes" and adds the optionflag
13 # to CFLAGS if it is understood. You can override the shellvar-default of
14 # CFLAGS of course. The order of arguments stems from the explicit macros
15 # like AX_CFLAGS_WARN_ALL.
17 # The cousin AX_CXXFLAGS_GCC_OPTION would check for an option to add to
18 # CXXFLAGS - and it uses the autoconf setup for C++ instead of C (since it
19 # is possible to use different compilers for C and C++).
21 # The macro is a lot simpler than any special AX_CFLAGS_* macro (or
22 # ac_cxx_rtti.m4 macro) but allows to check for arbitrary options.
23 # However, if you use this macro in a few places, it would be great if you
24 # would make up a new function-macro and submit it to the ac-archive.
26 # - $1 option-to-check-for : required ("-option" as non-value)
27 # - $2 shell-variable-to-add-to : CFLAGS (or CXXFLAGS in the other case)
28 # - $3 action-if-found : add value to shellvariable
29 # - $4 action-if-not-found : nothing
31 # Note: in earlier versions, $1-$2 were swapped. We try to detect the
32 # situation and accept a $2=~/-/ as being the old option-to-check-for.
34 # There are other variants that emerged from the original macro variant
35 # which did just test an option to be possibly added. However, some
36 # compilers accept an option silently, or possibly for just another option
37 # that was not intended. Therefore, we have to do a generic test for a
38 # compiler family. For gcc we check "-pedantic" being accepted which is
39 # also understood by compilers who just want to be compatible with gcc
40 # even when not being made from gcc sources.
42 # See also: AX_CFLAGS_SUN_OPTION, AX_CFLAGS_HPUX_OPTION,
43 # AX_CFLAGS_AIX_OPTION, and AX_CFLAGS_IRIX_OPTION.
51 # Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
53 # This program is free software; you can redistribute it and/or modify it
54 # under the terms of the GNU General Public License as published by the
55 # Free Software Foundation; either version 2 of the License, or (at your
56 # option) any later version.
58 # This program is distributed in the hope that it will be useful, but
59 # WITHOUT ANY WARRANTY; without even the implied warranty of
60 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
61 # Public License for more details.
63 # You should have received a copy of the GNU General Public License along
64 # with this program. If not, see <http://www.gnu.org/licenses/>.
66 # As a special exception, the respective Autoconf Macro's copyright owner
67 # gives unlimited permission to copy, distribute and modify the configure
68 # scripts that are the output of Autoconf when processing the Macro. You
69 # need not follow the terms of the GNU General Public License when using
70 # or distributing such scripts, even though portions of the text of the
71 # Macro appear in them. The GNU General Public License (GPL) does govern
72 # all other use of the material that constitutes the Autoconf Macro.
74 # This special exception to the GPL applies to versions of the Autoconf
75 # Macro released by the Autoconf Macro Archive. When you make and
76 # distribute a modified version of the Autoconf Macro, you may extend this
77 # special exception to the GPL to apply to your modified version as well.
79 AC_DEFUN([AX_CFLAGS_GCC_OPTION_OLD], [dnl
80 AS_VAR_PUSHDEF([FLAGS],[CFLAGS])dnl
81 AS_VAR_PUSHDEF([VAR],[ac_cv_cflags_gcc_option_$2])dnl
82 AC_CACHE_CHECK([m4_ifval($1,$1,FLAGS) for gcc m4_ifval($2,$2,-option)],
83 VAR,[VAR="no, unknown"
86 ac_save_[]FLAGS="$[]FLAGS"
88 in "-pedantic -Werror % m4_ifval($2,$2,-option)" dnl GCC
89 "-pedantic % m4_ifval($2,$2,-option) %% no, obsolete" dnl new GCC
91 do FLAGS="$ac_save_[]FLAGS "`echo $ac_arg | sed -e 's,%%.*,,' -e 's,%,,'`
92 AC_TRY_COMPILE([],[return 0;],
93 [VAR=`echo $ac_arg | sed -e 's,.*% *,,'` ; break])
95 FLAGS="$ac_save_[]FLAGS"
99 .ok|.ok,*) m4_ifvaln($3,$3) ;;
100 .|.no|.no,*) m4_ifvaln($4,$4) ;;
102 if echo " $[]m4_ifval($1,$1,FLAGS) " | grep " $VAR " 2>&1 >/dev/null
103 then AC_RUN_LOG([: m4_ifval($1,$1,FLAGS) does contain $VAR])
104 else AC_RUN_LOG([: m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $VAR"])
105 m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $VAR"
108 AS_VAR_POPDEF([VAR])dnl
109 AS_VAR_POPDEF([FLAGS])dnl
113 dnl the only difference - the LANG selection... and the default FLAGS
115 AC_DEFUN([AX_CXXFLAGS_GCC_OPTION_OLD], [dnl
116 AS_VAR_PUSHDEF([FLAGS],[CXXFLAGS])dnl
117 AS_VAR_PUSHDEF([VAR],[ac_cv_cxxflags_gcc_option_$2])dnl
118 AC_CACHE_CHECK([m4_ifval($1,$1,FLAGS) for gcc m4_ifval($2,$2,-option)],
119 VAR,[VAR="no, unknown"
122 ac_save_[]FLAGS="$[]FLAGS"
124 in "-pedantic -Werror % m4_ifval($2,$2,-option)" dnl GCC
125 "-pedantic % m4_ifval($2,$2,-option) %% no, obsolete" dnl new GCC
127 do FLAGS="$ac_save_[]FLAGS "`echo $ac_arg | sed -e 's,%%.*,,' -e 's,%,,'`
128 AC_TRY_COMPILE([],[return 0;],
129 [VAR=`echo $ac_arg | sed -e 's,.*% *,,'` ; break])
131 FLAGS="$ac_save_[]FLAGS"
135 .ok|.ok,*) m4_ifvaln($3,$3) ;;
136 .|.no|.no,*) m4_ifvaln($4,$4) ;;
138 if echo " $[]m4_ifval($1,$1,FLAGS) " | grep " $VAR " 2>&1 >/dev/null
139 then AC_RUN_LOG([: m4_ifval($1,$1,FLAGS) does contain $VAR])
140 else AC_RUN_LOG([: m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $VAR"])
141 m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $VAR"
144 AS_VAR_POPDEF([VAR])dnl
145 AS_VAR_POPDEF([FLAGS])dnl
148 dnl -------------------------------------------------------------------------
150 AC_DEFUN([AX_CFLAGS_GCC_OPTION_NEW], [dnl
151 AS_VAR_PUSHDEF([FLAGS],[CFLAGS])dnl
152 AS_VAR_PUSHDEF([VAR],[ac_cv_cflags_gcc_option_$1])dnl
153 AC_CACHE_CHECK([m4_ifval($2,$2,FLAGS) for gcc m4_ifval($1,$1,-option)],
154 VAR,[VAR="no, unknown"
157 ac_save_[]FLAGS="$[]FLAGS"
159 in "-pedantic -Werror % m4_ifval($1,$1,-option)" dnl GCC
160 "-pedantic % m4_ifval($1,$1,-option) %% no, obsolete" dnl new GCC
162 do FLAGS="$ac_save_[]FLAGS "`echo $ac_arg | sed -e 's,%%.*,,' -e 's,%,,'`
163 AC_TRY_COMPILE([],[return 0;],
164 [VAR=`echo $ac_arg | sed -e 's,.*% *,,'` ; break])
166 FLAGS="$ac_save_[]FLAGS"
170 .ok|.ok,*) m4_ifvaln($3,$3) ;;
171 .|.no|.no,*) m4_ifvaln($4,$4) ;;
173 if echo " $[]m4_ifval($2,$2,FLAGS) " | grep " $VAR " 2>&1 >/dev/null
174 then AC_RUN_LOG([: m4_ifval($2,$2,FLAGS) does contain $VAR])
175 else AC_RUN_LOG([: m4_ifval($2,$2,FLAGS)="$m4_ifval($2,$2,FLAGS) $VAR"])
176 m4_ifval($2,$2,FLAGS)="$m4_ifval($2,$2,FLAGS) $VAR"
179 AS_VAR_POPDEF([VAR])dnl
180 AS_VAR_POPDEF([FLAGS])dnl
184 dnl the only difference - the LANG selection... and the default FLAGS
186 AC_DEFUN([AX_CXXFLAGS_GCC_OPTION_NEW], [dnl
187 AS_VAR_PUSHDEF([FLAGS],[CXXFLAGS])dnl
188 AS_VAR_PUSHDEF([VAR],[ac_cv_cxxflags_gcc_option_$1])dnl
189 AC_CACHE_CHECK([m4_ifval($2,$2,FLAGS) for gcc m4_ifval($1,$1,-option)],
190 VAR,[VAR="no, unknown"
193 ac_save_[]FLAGS="$[]FLAGS"
195 in "-pedantic -Werror % m4_ifval($1,$1,-option)" dnl GCC
196 "-pedantic % m4_ifval($1,$1,-option) %% no, obsolete" dnl new GCC
198 do FLAGS="$ac_save_[]FLAGS "`echo $ac_arg | sed -e 's,%%.*,,' -e 's,%,,'`
199 AC_TRY_COMPILE([],[return 0;],
200 [VAR=`echo $ac_arg | sed -e 's,.*% *,,'` ; break])
202 FLAGS="$ac_save_[]FLAGS"
206 .ok|.ok,*) m4_ifvaln($3,$3) ;;
207 .|.no|.no,*) m4_ifvaln($4,$4) ;;
209 if echo " $[]m4_ifval($2,$2,FLAGS) " | grep " $VAR " 2>&1 >/dev/null
210 then AC_RUN_LOG([: m4_ifval($2,$2,FLAGS) does contain $VAR])
211 else AC_RUN_LOG([: m4_ifval($2,$2,FLAGS)="$m4_ifval($2,$2,FLAGS) $VAR"])
212 m4_ifval($2,$2,FLAGS)="$m4_ifval($2,$2,FLAGS) $VAR"
215 AS_VAR_POPDEF([VAR])dnl
216 AS_VAR_POPDEF([FLAGS])dnl
219 AC_DEFUN([AX_CFLAGS_GCC_OPTION],[ifelse(m4_bregexp([$2],[-]),-1,
220 [AX_CFLAGS_GCC_OPTION_NEW($@)],[AX_CFLAGS_GCC_OPTION_OLD($@)])])
222 AC_DEFUN([AX_CXXFLAGS_GCC_OPTION],[ifelse(m4_bregexp([$2],[-]),-1,
223 [AX_CXXFLAGS_GCC_OPTION_NEW($@)],[AX_CXXFLAGS_GCC_OPTION_OLD($@)])])