Merge changes from emacs-23
[bpt/emacs.git] / m4 / gnulib-common.m4
1 # gnulib-common.m4 serial 30
2 dnl Copyright (C) 2007-2011 Free Software Foundation, Inc.
3 dnl This file is free software; the Free Software Foundation
4 dnl gives unlimited permission to copy and/or distribute it,
5 dnl with or without modifications, as long as this notice is preserved.
6
7 # gl_COMMON
8 # is expanded unconditionally through gnulib-tool magic.
9 AC_DEFUN([gl_COMMON], [
10 dnl Use AC_REQUIRE here, so that the code is expanded once only.
11 AC_REQUIRE([gl_00GNULIB])
12 AC_REQUIRE([gl_COMMON_BODY])
13 ])
14 AC_DEFUN([gl_COMMON_BODY], [
15 AH_VERBATIM([_Noreturn],
16 [/* The _Noreturn keyword of draft C1X. */
17 #ifndef _Noreturn
18 # if (3 <= __GNUC__ || (__GNUC__ == 2 && 8 <= __GNUC_MINOR__) \
19 || 0x5110 <= __SUNPRO_C)
20 # define _Noreturn __attribute__ ((__noreturn__))
21 # elif 1200 <= _MSC_VER
22 # define _Noreturn __declspec (noreturn)
23 # else
24 # define _Noreturn
25 # endif
26 #endif
27 ])
28 AH_VERBATIM([isoc99_inline],
29 [/* Work around a bug in Apple GCC 4.0.1 build 5465: In C99 mode, it supports
30 the ISO C 99 semantics of 'extern inline' (unlike the GNU C semantics of
31 earlier versions), but does not display it by setting __GNUC_STDC_INLINE__.
32 __APPLE__ && __MACH__ test for MacOS X.
33 __APPLE_CC__ tests for the Apple compiler and its version.
34 __STDC_VERSION__ tests for the C99 mode. */
35 #if defined __APPLE__ && defined __MACH__ && __APPLE_CC__ >= 5465 && !defined __cplusplus && __STDC_VERSION__ >= 199901L && !defined __GNUC_STDC_INLINE__
36 # define __GNUC_STDC_INLINE__ 1
37 #endif])
38 AH_VERBATIM([unused_parameter],
39 [/* Define as a marker that can be attached to declarations that might not
40 be used. This helps to reduce warnings, such as from
41 GCC -Wunused-parameter. */
42 #if __GNUC__ >= 3 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 7)
43 # define _GL_UNUSED __attribute__ ((__unused__))
44 #else
45 # define _GL_UNUSED
46 #endif
47 /* The name _UNUSED_PARAMETER_ is an earlier spelling, although the name
48 is a misnomer outside of parameter lists. */
49 #define _UNUSED_PARAMETER_ _GL_UNUSED
50
51 /* The __pure__ attribute was added in gcc 2.96. */
52 #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
53 # define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
54 #else
55 # define _GL_ATTRIBUTE_PURE /* empty */
56 #endif
57
58 /* The __const__ attribute was added in gcc 2.95. */
59 #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 95)
60 # define _GL_ATTRIBUTE_CONST __attribute__ ((__const__))
61 #else
62 # define _GL_ATTRIBUTE_CONST /* empty */
63 #endif
64 ])
65 dnl Preparation for running test programs:
66 dnl Tell glibc to write diagnostics from -D_FORTIFY_SOURCE=2 to stderr, not
67 dnl to /dev/tty, so they can be redirected to log files. Such diagnostics
68 dnl arise e.g., in the macros gl_PRINTF_DIRECTIVE_N, gl_SNPRINTF_DIRECTIVE_N.
69 LIBC_FATAL_STDERR_=1
70 export LIBC_FATAL_STDERR_
71 ])
72
73 # gl_MODULE_INDICATOR_CONDITION
74 # expands to a C preprocessor expression that evaluates to 1 or 0, depending
75 # whether a gnulib module that has been requested shall be considered present
76 # or not.
77 m4_define([gl_MODULE_INDICATOR_CONDITION], [1])
78
79 # gl_MODULE_INDICATOR_SET_VARIABLE([modulename])
80 # sets the shell variable that indicates the presence of the given module to
81 # a C preprocessor expression that will evaluate to 1.
82 AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE],
83 [
84 gl_MODULE_INDICATOR_SET_VARIABLE_AUX(
85 [GNULIB_[]m4_translit([[$1]],
86 [abcdefghijklmnopqrstuvwxyz./-],
87 [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])],
88 [gl_MODULE_INDICATOR_CONDITION])
89 ])
90
91 # gl_MODULE_INDICATOR_SET_VARIABLE_AUX([variable])
92 # modifies the shell variable to include the gl_MODULE_INDICATOR_CONDITION.
93 # The shell variable's value is a C preprocessor expression that evaluates
94 # to 0 or 1.
95 AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX],
96 [
97 m4_if(m4_defn([gl_MODULE_INDICATOR_CONDITION]), [1],
98 [
99 dnl Simplify the expression VALUE || 1 to 1.
100 $1=1
101 ],
102 [gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([$1],
103 [gl_MODULE_INDICATOR_CONDITION])])
104 ])
105
106 # gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([variable], [condition])
107 # modifies the shell variable to include the given condition. The shell
108 # variable's value is a C preprocessor expression that evaluates to 0 or 1.
109 AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR],
110 [
111 dnl Simplify the expression 1 || CONDITION to 1.
112 if test "$[]$1" != 1; then
113 dnl Simplify the expression 0 || CONDITION to CONDITION.
114 if test "$[]$1" = 0; then
115 $1=$2
116 else
117 $1="($[]$1 || $2)"
118 fi
119 fi
120 ])
121
122 # gl_MODULE_INDICATOR([modulename])
123 # defines a C macro indicating the presence of the given module
124 # in a location where it can be used.
125 # | Value | Value |
126 # | in lib/ | in tests/ |
127 # --------------------------------------------+---------+-----------+
128 # Module present among main modules: | 1 | 1 |
129 # --------------------------------------------+---------+-----------+
130 # Module present among tests-related modules: | 0 | 1 |
131 # --------------------------------------------+---------+-----------+
132 # Module not present at all: | 0 | 0 |
133 # --------------------------------------------+---------+-----------+
134 AC_DEFUN([gl_MODULE_INDICATOR],
135 [
136 AC_DEFINE_UNQUOTED([GNULIB_]m4_translit([[$1]],
137 [abcdefghijklmnopqrstuvwxyz./-],
138 [ABCDEFGHIJKLMNOPQRSTUVWXYZ___]),
139 [gl_MODULE_INDICATOR_CONDITION],
140 [Define to a C preprocessor expression that evaluates to 1 or 0,
141 depending whether the gnulib module $1 shall be considered present.])
142 ])
143
144 # gl_MODULE_INDICATOR_FOR_TESTS([modulename])
145 # defines a C macro indicating the presence of the given module
146 # in lib or tests. This is useful to determine whether the module
147 # should be tested.
148 # | Value | Value |
149 # | in lib/ | in tests/ |
150 # --------------------------------------------+---------+-----------+
151 # Module present among main modules: | 1 | 1 |
152 # --------------------------------------------+---------+-----------+
153 # Module present among tests-related modules: | 1 | 1 |
154 # --------------------------------------------+---------+-----------+
155 # Module not present at all: | 0 | 0 |
156 # --------------------------------------------+---------+-----------+
157 AC_DEFUN([gl_MODULE_INDICATOR_FOR_TESTS],
158 [
159 AC_DEFINE([GNULIB_TEST_]m4_translit([[$1]],
160 [abcdefghijklmnopqrstuvwxyz./-],
161 [ABCDEFGHIJKLMNOPQRSTUVWXYZ___]), [1],
162 [Define to 1 when the gnulib module $1 should be tested.])
163 ])
164
165 # gl_ASSERT_NO_GNULIB_POSIXCHECK
166 # asserts that there will never be a need to #define GNULIB_POSIXCHECK.
167 # and thereby enables an optimization of configure and config.h.
168 # Used by Emacs.
169 AC_DEFUN([gl_ASSERT_NO_GNULIB_POSIXCHECK],
170 [
171 dnl Override gl_WARN_ON_USE_PREPARE.
172 dnl But hide this definition from 'aclocal'.
173 AC_DEFUN([gl_W][ARN_ON_USE_PREPARE], [])
174 ])
175
176 # gl_ASSERT_NO_GNULIB_TESTS
177 # asserts that there will be no gnulib tests in the scope of the configure.ac
178 # and thereby enables an optimization of config.h.
179 # Used by Emacs.
180 AC_DEFUN([gl_ASSERT_NO_GNULIB_TESTS],
181 [
182 dnl Override gl_MODULE_INDICATOR_FOR_TESTS.
183 AC_DEFUN([gl_MODULE_INDICATOR_FOR_TESTS], [])
184 ])
185
186 # Test whether <features.h> exists.
187 # Set HAVE_FEATURES_H.
188 AC_DEFUN([gl_FEATURES_H],
189 [
190 AC_CHECK_HEADERS_ONCE([features.h])
191 if test $ac_cv_header_features_h = yes; then
192 HAVE_FEATURES_H=1
193 else
194 HAVE_FEATURES_H=0
195 fi
196 AC_SUBST([HAVE_FEATURES_H])
197 ])
198
199 # m4_foreach_w
200 # is a backport of autoconf-2.59c's m4_foreach_w.
201 # Remove this macro when we can assume autoconf >= 2.60.
202 m4_ifndef([m4_foreach_w],
203 [m4_define([m4_foreach_w],
204 [m4_foreach([$1], m4_split(m4_normalize([$2]), [ ]), [$3])])])
205
206 # AS_VAR_IF(VAR, VALUE, [IF-MATCH], [IF-NOT-MATCH])
207 # ----------------------------------------------------
208 # Backport of autoconf-2.63b's macro.
209 # Remove this macro when we can assume autoconf >= 2.64.
210 m4_ifndef([AS_VAR_IF],
211 [m4_define([AS_VAR_IF],
212 [AS_IF([test x"AS_VAR_GET([$1])" = x""$2], [$3], [$4])])])
213
214 # gl_PROG_AR_RANLIB
215 # Determines the values for AR, ARFLAGS, RANLIB that fit with the compiler.
216 # The user can set the variables AR, ARFLAGS, RANLIB if he wants to override
217 # the values.
218 AC_DEFUN([gl_PROG_AR_RANLIB],
219 [
220 dnl Minix 3 comes with two toolchains: The Amsterdam Compiler Kit compiler
221 dnl as "cc", and GCC as "gcc". They have different object file formats and
222 dnl library formats. In particular, the GNU binutils programs ar, ranlib
223 dnl produce libraries that work only with gcc, not with cc.
224 AC_REQUIRE([AC_PROG_CC])
225 AC_CACHE_CHECK([for Minix Amsterdam compiler], [gl_cv_c_amsterdam_compiler],
226 [
227 AC_EGREP_CPP([Amsterdam],
228 [
229 #ifdef __ACK__
230 Amsterdam
231 #endif
232 ],
233 [gl_cv_c_amsterdam_compiler=yes],
234 [gl_cv_c_amsterdam_compiler=no])
235 ])
236 if test -z "$AR"; then
237 if test $gl_cv_c_amsterdam_compiler = yes; then
238 AR='cc -c.a'
239 if test -z "$ARFLAGS"; then
240 ARFLAGS='-o'
241 fi
242 else
243 dnl Use the Automake-documented default values for AR and ARFLAGS,
244 dnl but prefer ${host}-ar over ar (useful for cross-compiling).
245 AC_CHECK_TOOL([AR], [ar], [ar])
246 if test -z "$ARFLAGS"; then
247 ARFLAGS='cru'
248 fi
249 fi
250 else
251 if test -z "$ARFLAGS"; then
252 ARFLAGS='cru'
253 fi
254 fi
255 AC_SUBST([AR])
256 AC_SUBST([ARFLAGS])
257 if test -z "$RANLIB"; then
258 if test $gl_cv_c_amsterdam_compiler = yes; then
259 RANLIB=':'
260 else
261 dnl Use the ranlib program if it is available.
262 AC_PROG_RANLIB
263 fi
264 fi
265 AC_SUBST([RANLIB])
266 ])
267
268 # AC_PROG_MKDIR_P
269 # is a backport of autoconf-2.60's AC_PROG_MKDIR_P, with a fix
270 # for interoperability with automake-1.9.6 from autoconf-2.62.
271 # Remove this macro when we can assume autoconf >= 2.62 or
272 # autoconf >= 2.60 && automake >= 1.10.
273 m4_ifdef([AC_PROG_MKDIR_P], [
274 dnl For automake-1.9.6 && autoconf < 2.62: Ensure MKDIR_P is AC_SUBSTed.
275 m4_define([AC_PROG_MKDIR_P],
276 m4_defn([AC_PROG_MKDIR_P])[
277 AC_SUBST([MKDIR_P])])], [
278 dnl For autoconf < 2.60: Backport of AC_PROG_MKDIR_P.
279 AC_DEFUN_ONCE([AC_PROG_MKDIR_P],
280 [AC_REQUIRE([AM_PROG_MKDIR_P])dnl defined by automake
281 MKDIR_P='$(mkdir_p)'
282 AC_SUBST([MKDIR_P])])])
283
284 # AC_C_RESTRICT
285 # This definition overrides the AC_C_RESTRICT macro from autoconf 2.60..2.61,
286 # so that mixed use of GNU C and GNU C++ and mixed use of Sun C and Sun C++
287 # works.
288 # This definition can be removed once autoconf >= 2.62 can be assumed.
289 m4_if(m4_version_compare(m4_defn([m4_PACKAGE_VERSION]),[2.62]),[-1],[
290 AC_DEFUN([AC_C_RESTRICT],
291 [AC_CACHE_CHECK([for C/C++ restrict keyword], [ac_cv_c_restrict],
292 [ac_cv_c_restrict=no
293 # The order here caters to the fact that C++ does not require restrict.
294 for ac_kw in __restrict __restrict__ _Restrict restrict; do
295 AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
296 [[typedef int * int_ptr;
297 int foo (int_ptr $ac_kw ip) {
298 return ip[0];
299 }]],
300 [[int s[1];
301 int * $ac_kw t = s;
302 t[0] = 0;
303 return foo(t)]])],
304 [ac_cv_c_restrict=$ac_kw])
305 test "$ac_cv_c_restrict" != no && break
306 done
307 ])
308 AH_VERBATIM([restrict],
309 [/* Define to the equivalent of the C99 'restrict' keyword, or to
310 nothing if this is not supported. Do not define if restrict is
311 supported directly. */
312 #undef restrict
313 /* Work around a bug in Sun C++: it does not support _Restrict, even
314 though the corresponding Sun C compiler does, which causes
315 "#define restrict _Restrict" in the previous line. Perhaps some future
316 version of Sun C++ will work with _Restrict; if so, it'll probably
317 define __RESTRICT, just as Sun C does. */
318 #if defined __SUNPRO_CC && !defined __RESTRICT
319 # define _Restrict
320 #endif])
321 case $ac_cv_c_restrict in
322 restrict) ;;
323 no) AC_DEFINE([restrict], []) ;;
324 *) AC_DEFINE_UNQUOTED([restrict], [$ac_cv_c_restrict]) ;;
325 esac
326 ])
327 ])
328
329 # gl_BIGENDIAN
330 # is like AC_C_BIGENDIAN, except that it can be AC_REQUIREd.
331 # Note that AC_REQUIRE([AC_C_BIGENDIAN]) does not work reliably because some
332 # macros invoke AC_C_BIGENDIAN with arguments.
333 AC_DEFUN([gl_BIGENDIAN],
334 [
335 AC_C_BIGENDIAN
336 ])
337
338 # gl_CACHE_VAL_SILENT(cache-id, command-to-set-it)
339 # is like AC_CACHE_VAL(cache-id, command-to-set-it), except that it does not
340 # output a spurious "(cached)" mark in the midst of other configure output.
341 # This macro should be used instead of AC_CACHE_VAL when it is not surrounded
342 # by an AC_MSG_CHECKING/AC_MSG_RESULT pair.
343 AC_DEFUN([gl_CACHE_VAL_SILENT],
344 [
345 saved_as_echo_n="$as_echo_n"
346 as_echo_n=':'
347 AC_CACHE_VAL([$1], [$2])
348 as_echo_n="$saved_as_echo_n"
349 ])