1 # ===========================================================================
2 # http://www.gnu.org/software/autoconf-archive/ax_cflags_gcc_option.html
3 # ===========================================================================
7 # AX_CFLAGS_GCC_OPTION (optionflag [,[shellvar][,[A][,[NA]]])
11 # AX_CFLAGS_GCC_OPTION(-fomit-frame-pointer) would show a message like
12 # "checking CFLAGS for gcc -fomit-frame-pointer ... yes" and add the
13 # optionflag to CFLAGS if it is understood. You can override the
14 # shellvar-default of CFLAGS of course. The order of arguments stems from
15 # the explicit macros 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 # ax_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.
47 # Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
49 # This program is free software; you can redistribute it and/or modify it
50 # under the terms of the GNU General Public License as published by the
51 # Free Software Foundation; either version 3 of the License, or (at your
52 # option) any later version.
54 # This program is distributed in the hope that it will be useful, but
55 # WITHOUT ANY WARRANTY; without even the implied warranty of
56 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
57 # Public License for more details.
59 # You should have received a copy of the GNU General Public License along
60 # with this program. If not, see <http://www.gnu.org/licenses/>.
62 # As a special exception, the respective Autoconf Macro's copyright owner
63 # gives unlimited permission to copy, distribute and modify the configure
64 # scripts that are the output of Autoconf when processing the Macro. You
65 # need not follow the terms of the GNU General Public License when using
66 # or distributing such scripts, even though portions of the text of the
67 # Macro appear in them. The GNU General Public License (GPL) does govern
68 # all other use of the material that constitutes the Autoconf Macro.
70 # This special exception to the GPL applies to versions of the Autoconf
71 # Macro released by the Autoconf Archive. When you make and distribute a
72 # modified version of the Autoconf Macro, you may extend this special
73 # exception to the GPL to apply to your modified version as well.
77 AC_DEFUN([AX_CFLAGS_GCC_OPTION_OLD], [dnl
78 AS_VAR_PUSHDEF([FLAGS],[CFLAGS])dnl
79 AS_VAR_PUSHDEF([VAR],[ax_cv_cflags_gcc_option_$2])dnl
80 AC_CACHE_CHECK([m4_ifval($1,$1,FLAGS) for gcc m4_ifval($2,$2,-option)],
81 VAR,[AS_VAR_SET([VAR],["no, unknown"])
84 ac_save_[]FLAGS="$[]FLAGS"
86 in "-pedantic -Werror % m4_ifval($2,$2,-option)" dnl GCC
87 "-pedantic % m4_ifval($2,$2,-option) %% no, obsolete" dnl new GCC
89 do FLAGS="$ac_save_[]FLAGS "`echo $ac_arg | sed -e 's,%%.*,,' -e 's,%,,'`
90 AC_TRY_COMPILE([],[return 0;],
91 [AS_VAR_SET([VAR],[`echo $ac_arg | sed -e 's,.*% *,,'`]); break])
93 FLAGS="$ac_save_[]FLAGS"
96 m4_ifdef([AS_VAR_COPY],[AS_VAR_COPY([var],[VAR])],[var=AS_VAR_GET([VAR])])
98 .ok|.ok,*) m4_ifvaln($3,$3) ;;
99 .|.no|.no,*) m4_ifvaln($4,$4) ;;
101 if echo " $[]m4_ifval($1,$1,FLAGS) " | grep " $var " 2>&1 >/dev/null
102 then AC_RUN_LOG([: m4_ifval($1,$1,FLAGS) does contain $var])
103 else AC_RUN_LOG([: m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $var"])
104 m4_ifval($1,$1,FLAGS)="$m4_ifval($1,$1,FLAGS) $var"
107 AS_VAR_POPDEF([VAR])dnl
108 AS_VAR_POPDEF([FLAGS])dnl
112 dnl the only difference - the LANG selection... and the default FLAGS
114 AC_DEFUN([AX_CXXFLAGS_GCC_OPTION_OLD], [dnl
115 AS_VAR_PUSHDEF([FLAGS],[CXXFLAGS])dnl
116 AS_VAR_PUSHDEF([VAR],[ax_cv_cxxflags_gcc_option_$2])dnl
117 AC_CACHE_CHECK([m4_ifval($1,$1,FLAGS) for gcc m4_ifval($2,$2,-option)],
118 VAR,[AS_VAR_SET([VAR],["no, unknown"])
121 ac_save_[]FLAGS="$[]FLAGS"
123 in "-pedantic -Werror % m4_ifval($2,$2,-option)" dnl GCC
124 "-pedantic % m4_ifval($2,$2,-option) %% no, obsolete" dnl new GCC
126 do FLAGS="$ac_save_[]FLAGS "`echo $ac_arg | sed -e 's,%%.*,,' -e 's,%,,'`
127 AC_TRY_COMPILE([],[return 0;],
128 [AS_VAR_SET([VAR],[`echo $ac_arg | sed -e 's,.*% *,,'`]); break])
130 FLAGS="$ac_save_[]FLAGS"
133 m4_ifdef([AS_VAR_COPY],[AS_VAR_COPY([var],[VAR])],[var=AS_VAR_GET([VAR])])
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],[ax_cv_cflags_gcc_option_$1])dnl
153 AC_CACHE_CHECK([m4_ifval($2,$2,FLAGS) for gcc m4_ifval($1,$1,-option)],
154 VAR,[AS_VAR_SET([VAR],["no, unknown"])
157 ac_save_[]FLAGS="$[]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 [AS_VAR_SET([VAR],[`echo $ac_arg | sed -e 's,.*% *,,'`]); break])
166 FLAGS="$ac_save_[]FLAGS"
169 m4_ifdef([AS_VAR_COPY],[AS_VAR_COPY([var],[VAR])],[var=AS_VAR_GET([VAR])])
171 .ok|.ok,*) m4_ifvaln($3,$3) ;;
172 .|.no|.no,*) m4_ifvaln($4,$4) ;;
174 if echo " $[]m4_ifval($2,$2,FLAGS) " | grep " $var " 2>&1 >/dev/null
175 then AC_RUN_LOG([: m4_ifval($2,$2,FLAGS) does contain $var])
176 else AC_RUN_LOG([: m4_ifval($2,$2,FLAGS)="$m4_ifval($2,$2,FLAGS) $var"])
177 m4_ifval($2,$2,FLAGS)="$m4_ifval($2,$2,FLAGS) $var"
180 AS_VAR_POPDEF([VAR])dnl
181 AS_VAR_POPDEF([FLAGS])dnl
185 dnl the only difference - the LANG selection... and the default FLAGS
187 AC_DEFUN([AX_CXXFLAGS_GCC_OPTION_NEW], [dnl
188 AS_VAR_PUSHDEF([FLAGS],[CXXFLAGS])dnl
189 AS_VAR_PUSHDEF([VAR],[ax_cv_cxxflags_gcc_option_$1])dnl
190 AC_CACHE_CHECK([m4_ifval($2,$2,FLAGS) for gcc m4_ifval($1,$1,-option)],
191 VAR,[AS_VAR_SET([VAR],["no, unknown"])
194 ac_save_[]FLAGS="$[]FLAGS"
196 in "-pedantic -Werror % m4_ifval($1,$1,-option)" dnl GCC
197 "-pedantic % m4_ifval($1,$1,-option) %% no, obsolete" dnl new GCC
199 do FLAGS="$ac_save_[]FLAGS "`echo $ac_arg | sed -e 's,%%.*,,' -e 's,%,,'`
200 AC_TRY_COMPILE([],[return 0;],
201 [AS_VAR_SET([VAR],[`echo $ac_arg | sed -e 's,.*% *,,'`]); break])
203 FLAGS="$ac_save_[]FLAGS"
206 m4_ifdef([AS_VAR_COPY],[AS_VAR_COPY([var],[VAR])],[var=AS_VAR_GET([VAR])])
208 .ok|.ok,*) m4_ifvaln($3,$3) ;;
209 .|.no|.no,*) m4_ifvaln($4,$4) ;;
211 if echo " $[]m4_ifval($2,$2,FLAGS) " | grep " $var " 2>&1 >/dev/null
212 then AC_RUN_LOG([: m4_ifval($2,$2,FLAGS) does contain $var])
213 else AC_RUN_LOG([: m4_ifval($2,$2,FLAGS)="$m4_ifval($2,$2,FLAGS) $var"])
214 m4_ifval($2,$2,FLAGS)="$m4_ifval($2,$2,FLAGS) $var"
217 AS_VAR_POPDEF([VAR])dnl
218 AS_VAR_POPDEF([FLAGS])dnl
221 AC_DEFUN([AX_CFLAGS_GCC_OPTION],[ifelse(m4_bregexp([$2],[-]),-1,
222 [AX_CFLAGS_GCC_OPTION_NEW($@)],[AX_CFLAGS_GCC_OPTION_OLD($@)])])
224 AC_DEFUN([AX_CXXFLAGS_GCC_OPTION],[ifelse(m4_bregexp([$2],[-]),-1,
225 [AX_CXXFLAGS_GCC_OPTION_NEW($@)],[AX_CXXFLAGS_GCC_OPTION_OLD($@)])])