1# gnulib-common.m4 serial 36
2dnl Copyright (C) 2007-2014 Free Software Foundation, Inc.
3dnl This file is free software; the Free Software Foundation
4dnl gives unlimited permission to copy and/or distribute it,
5dnl with or without modifications, as long as this notice is preserved.
6
7# gl_COMMON
8# is expanded unconditionally through gnulib-tool magic.
9AC_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])
14AC_DEFUN([gl_COMMON_BODY], [
15  AH_VERBATIM([_Noreturn],
16[/* The _Noreturn keyword of C11.  */
17#if ! (defined _Noreturn \
18       || (defined __STDC_VERSION__ && 201112 <= __STDC_VERSION__))
19# if (3 <= __GNUC__ || (__GNUC__ == 2 && 8 <= __GNUC_MINOR__) \
20      || 0x5110 <= __SUNPRO_C)
21#  define _Noreturn __attribute__ ((__noreturn__))
22# elif defined _MSC_VER && 1200 <= _MSC_VER
23#  define _Noreturn __declspec (noreturn)
24# else
25#  define _Noreturn
26# endif
27#endif
28])
29  AH_VERBATIM([isoc99_inline],
30[/* Work around a bug in Apple GCC 4.0.1 build 5465: In C99 mode, it supports
31   the ISO C 99 semantics of 'extern inline' (unlike the GNU C semantics of
32   earlier versions), but does not display it by setting __GNUC_STDC_INLINE__.
33   __APPLE__ && __MACH__ test for Mac OS X.
34   __APPLE_CC__ tests for the Apple compiler and its version.
35   __STDC_VERSION__ tests for the C99 mode.  */
36#if defined __APPLE__ && defined __MACH__ && __APPLE_CC__ >= 5465 && !defined __cplusplus && __STDC_VERSION__ >= 199901L && !defined __GNUC_STDC_INLINE__
37# define __GNUC_STDC_INLINE__ 1
38#endif])
39  AH_VERBATIM([unused_parameter],
40[/* Define as a marker that can be attached to declarations that might not
41    be used.  This helps to reduce warnings, such as from
42    GCC -Wunused-parameter.  */
43#if __GNUC__ >= 3 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 7)
44# define _GL_UNUSED __attribute__ ((__unused__))
45#else
46# define _GL_UNUSED
47#endif
48/* The name _UNUSED_PARAMETER_ is an earlier spelling, although the name
49   is a misnomer outside of parameter lists.  */
50#define _UNUSED_PARAMETER_ _GL_UNUSED
51
52/* gcc supports the "unused" attribute on possibly unused labels, and
53   g++ has since version 4.5.  Note to support C++ as well as C,
54   _GL_UNUSED_LABEL should be used with a trailing ;  */
55#if !defined __cplusplus || __GNUC__ > 4 \
56    || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)
57# define _GL_UNUSED_LABEL _GL_UNUSED
58#else
59# define _GL_UNUSED_LABEL
60#endif
61
62/* The __pure__ attribute was added in gcc 2.96.  */
63#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
64# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
65#else
66# define _GL_ATTRIBUTE_PURE /* empty */
67#endif
68
69/* The __const__ attribute was added in gcc 2.95.  */
70#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 95)
71# define _GL_ATTRIBUTE_CONST __attribute__ ((__const__))
72#else
73# define _GL_ATTRIBUTE_CONST /* empty */
74#endif
75])
76  dnl Preparation for running test programs:
77  dnl Tell glibc to write diagnostics from -D_FORTIFY_SOURCE=2 to stderr, not
78  dnl to /dev/tty, so they can be redirected to log files.  Such diagnostics
79  dnl arise e.g., in the macros gl_PRINTF_DIRECTIVE_N, gl_SNPRINTF_DIRECTIVE_N.
80  LIBC_FATAL_STDERR_=1
81  export LIBC_FATAL_STDERR_
82])
83
84# gl_MODULE_INDICATOR_CONDITION
85# expands to a C preprocessor expression that evaluates to 1 or 0, depending
86# whether a gnulib module that has been requested shall be considered present
87# or not.
88m4_define([gl_MODULE_INDICATOR_CONDITION], [1])
89
90# gl_MODULE_INDICATOR_SET_VARIABLE([modulename])
91# sets the shell variable that indicates the presence of the given module to
92# a C preprocessor expression that will evaluate to 1.
93AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE],
94[
95  gl_MODULE_INDICATOR_SET_VARIABLE_AUX(
96    [GNULIB_[]m4_translit([[$1]],
97                          [abcdefghijklmnopqrstuvwxyz./-],
98                          [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])],
99    [gl_MODULE_INDICATOR_CONDITION])
100])
101
102# gl_MODULE_INDICATOR_SET_VARIABLE_AUX([variable])
103# modifies the shell variable to include the gl_MODULE_INDICATOR_CONDITION.
104# The shell variable's value is a C preprocessor expression that evaluates
105# to 0 or 1.
106AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX],
107[
108  m4_if(m4_defn([gl_MODULE_INDICATOR_CONDITION]), [1],
109    [
110     dnl Simplify the expression VALUE || 1 to 1.
111     $1=1
112    ],
113    [gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([$1],
114                                             [gl_MODULE_INDICATOR_CONDITION])])
115])
116
117# gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([variable], [condition])
118# modifies the shell variable to include the given condition.  The shell
119# variable's value is a C preprocessor expression that evaluates to 0 or 1.
120AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR],
121[
122  dnl Simplify the expression 1 || CONDITION to 1.
123  if test "$[]$1" != 1; then
124    dnl Simplify the expression 0 || CONDITION to CONDITION.
125    if test "$[]$1" = 0; then
126      $1=$2
127    else
128      $1="($[]$1 || $2)"
129    fi
130  fi
131])
132
133# gl_MODULE_INDICATOR([modulename])
134# defines a C macro indicating the presence of the given module
135# in a location where it can be used.
136#                                             |  Value  |   Value   |
137#                                             | in lib/ | in tests/ |
138# --------------------------------------------+---------+-----------+
139# Module present among main modules:          |    1    |     1     |
140# --------------------------------------------+---------+-----------+
141# Module present among tests-related modules: |    0    |     1     |
142# --------------------------------------------+---------+-----------+
143# Module not present at all:                  |    0    |     0     |
144# --------------------------------------------+---------+-----------+
145AC_DEFUN([gl_MODULE_INDICATOR],
146[
147  AC_DEFINE_UNQUOTED([GNULIB_]m4_translit([[$1]],
148      [abcdefghijklmnopqrstuvwxyz./-],
149      [ABCDEFGHIJKLMNOPQRSTUVWXYZ___]),
150    [gl_MODULE_INDICATOR_CONDITION],
151    [Define to a C preprocessor expression that evaluates to 1 or 0,
152     depending whether the gnulib module $1 shall be considered present.])
153])
154
155# gl_MODULE_INDICATOR_FOR_TESTS([modulename])
156# defines a C macro indicating the presence of the given module
157# in lib or tests. This is useful to determine whether the module
158# should be tested.
159#                                             |  Value  |   Value   |
160#                                             | in lib/ | in tests/ |
161# --------------------------------------------+---------+-----------+
162# Module present among main modules:          |    1    |     1     |
163# --------------------------------------------+---------+-----------+
164# Module present among tests-related modules: |    1    |     1     |
165# --------------------------------------------+---------+-----------+
166# Module not present at all:                  |    0    |     0     |
167# --------------------------------------------+---------+-----------+
168AC_DEFUN([gl_MODULE_INDICATOR_FOR_TESTS],
169[
170  AC_DEFINE([GNULIB_TEST_]m4_translit([[$1]],
171      [abcdefghijklmnopqrstuvwxyz./-],
172      [ABCDEFGHIJKLMNOPQRSTUVWXYZ___]), [1],
173    [Define to 1 when the gnulib module $1 should be tested.])
174])
175
176# gl_ASSERT_NO_GNULIB_POSIXCHECK
177# asserts that there will never be a need to #define GNULIB_POSIXCHECK.
178# and thereby enables an optimization of configure and config.h.
179# Used by Emacs.
180AC_DEFUN([gl_ASSERT_NO_GNULIB_POSIXCHECK],
181[
182  dnl Override gl_WARN_ON_USE_PREPARE.
183  dnl But hide this definition from 'aclocal'.
184  AC_DEFUN([gl_W][ARN_ON_USE_PREPARE], [])
185])
186
187# gl_ASSERT_NO_GNULIB_TESTS
188# asserts that there will be no gnulib tests in the scope of the configure.ac
189# and thereby enables an optimization of config.h.
190# Used by Emacs.
191AC_DEFUN([gl_ASSERT_NO_GNULIB_TESTS],
192[
193  dnl Override gl_MODULE_INDICATOR_FOR_TESTS.
194  AC_DEFUN([gl_MODULE_INDICATOR_FOR_TESTS], [])
195])
196
197# Test whether <features.h> exists.
198# Set HAVE_FEATURES_H.
199AC_DEFUN([gl_FEATURES_H],
200[
201  AC_CHECK_HEADERS_ONCE([features.h])
202  if test $ac_cv_header_features_h = yes; then
203    HAVE_FEATURES_H=1
204  else
205    HAVE_FEATURES_H=0
206  fi
207  AC_SUBST([HAVE_FEATURES_H])
208])
209
210# m4_foreach_w
211# is a backport of autoconf-2.59c's m4_foreach_w.
212# Remove this macro when we can assume autoconf >= 2.60.
213m4_ifndef([m4_foreach_w],
214  [m4_define([m4_foreach_w],
215    [m4_foreach([$1], m4_split(m4_normalize([$2]), [ ]), [$3])])])
216
217# AS_VAR_IF(VAR, VALUE, [IF-MATCH], [IF-NOT-MATCH])
218# ----------------------------------------------------
219# Backport of autoconf-2.63b's macro.
220# Remove this macro when we can assume autoconf >= 2.64.
221m4_ifndef([AS_VAR_IF],
222[m4_define([AS_VAR_IF],
223[AS_IF([test x"AS_VAR_GET([$1])" = x""$2], [$3], [$4])])])
224
225# gl_PROG_CC_C99
226# Modifies the value of the shell variable CC in an attempt to make $CC
227# understand ISO C99 source code.
228# This is like AC_PROG_CC_C99, except that
229# - AC_PROG_CC_C99 did not exist in Autoconf versions < 2.60,
230# - AC_PROG_CC_C99 does not mix well with AC_PROG_CC_STDC
231#   <http://lists.gnu.org/archive/html/bug-gnulib/2011-09/msg00367.html>,
232#   but many more packages use AC_PROG_CC_STDC than AC_PROG_CC_C99
233#   <http://lists.gnu.org/archive/html/bug-gnulib/2011-09/msg00441.html>.
234# Remaining problems:
235# - When AC_PROG_CC_STDC is invoked twice, it adds the C99 enabling options
236#   to CC twice
237#   <http://lists.gnu.org/archive/html/bug-gnulib/2011-09/msg00431.html>.
238# - AC_PROG_CC_STDC is likely to change now that C11 is an ISO standard.
239AC_DEFUN([gl_PROG_CC_C99],
240[
241  dnl Change that version number to the minimum Autoconf version that supports
242  dnl mixing AC_PROG_CC_C99 calls with AC_PROG_CC_STDC calls.
243  m4_version_prereq([9.0],
244    [AC_REQUIRE([AC_PROG_CC_C99])],
245    [AC_REQUIRE([AC_PROG_CC_STDC])])
246])
247
248# gl_PROG_AR_RANLIB
249# Determines the values for AR, ARFLAGS, RANLIB that fit with the compiler.
250# The user can set the variables AR, ARFLAGS, RANLIB if he wants to override
251# the values.
252AC_DEFUN([gl_PROG_AR_RANLIB],
253[
254  dnl Minix 3 comes with two toolchains: The Amsterdam Compiler Kit compiler
255  dnl as "cc", and GCC as "gcc". They have different object file formats and
256  dnl library formats. In particular, the GNU binutils programs ar, ranlib
257  dnl produce libraries that work only with gcc, not with cc.
258  AC_REQUIRE([AC_PROG_CC])
259  AC_CACHE_CHECK([for Minix Amsterdam compiler], [gl_cv_c_amsterdam_compiler],
260    [
261      AC_EGREP_CPP([Amsterdam],
262        [
263#ifdef __ACK__
264Amsterdam
265#endif
266        ],
267        [gl_cv_c_amsterdam_compiler=yes],
268        [gl_cv_c_amsterdam_compiler=no])
269    ])
270  if test -z "$AR"; then
271    if test $gl_cv_c_amsterdam_compiler = yes; then
272      AR='cc -c.a'
273      if test -z "$ARFLAGS"; then
274        ARFLAGS='-o'
275      fi
276    else
277      dnl Use the Automake-documented default values for AR and ARFLAGS,
278      dnl but prefer ${host}-ar over ar (useful for cross-compiling).
279      AC_CHECK_TOOL([AR], [ar], [ar])
280      if test -z "$ARFLAGS"; then
281        ARFLAGS='cru'
282      fi
283    fi
284  else
285    if test -z "$ARFLAGS"; then
286      ARFLAGS='cru'
287    fi
288  fi
289  AC_SUBST([AR])
290  AC_SUBST([ARFLAGS])
291  if test -z "$RANLIB"; then
292    if test $gl_cv_c_amsterdam_compiler = yes; then
293      RANLIB=':'
294    else
295      dnl Use the ranlib program if it is available.
296      AC_PROG_RANLIB
297    fi
298  fi
299  AC_SUBST([RANLIB])
300])
301
302# AC_PROG_MKDIR_P
303# is a backport of autoconf-2.60's AC_PROG_MKDIR_P, with a fix
304# for interoperability with automake-1.9.6 from autoconf-2.62.
305# Remove this macro when we can assume autoconf >= 2.62 or
306# autoconf >= 2.60 && automake >= 1.10.
307# AC_AUTOCONF_VERSION was introduced in 2.62, so use that as the witness.
308m4_ifndef([AC_AUTOCONF_VERSION],[
309m4_ifdef([AC_PROG_MKDIR_P], [
310  dnl For automake-1.9.6 && autoconf < 2.62: Ensure MKDIR_P is AC_SUBSTed.
311  m4_define([AC_PROG_MKDIR_P],
312    m4_defn([AC_PROG_MKDIR_P])[
313    AC_SUBST([MKDIR_P])])], [
314  dnl For autoconf < 2.60: Backport of AC_PROG_MKDIR_P.
315  AC_DEFUN_ONCE([AC_PROG_MKDIR_P],
316    [AC_REQUIRE([AM_PROG_MKDIR_P])dnl defined by automake
317     MKDIR_P='$(mkdir_p)'
318     AC_SUBST([MKDIR_P])])])
319])
320
321# AC_C_RESTRICT
322# This definition is copied from post-2.69 Autoconf and overrides the
323# AC_C_RESTRICT macro from autoconf 2.60..2.69.  It can be removed
324# once autoconf >= 2.70 can be assumed.  It's painful to check version
325# numbers, and in practice this macro is more up-to-date than Autoconf
326# is, so override Autoconf unconditionally.
327AC_DEFUN([AC_C_RESTRICT],
328[AC_CACHE_CHECK([for C/C++ restrict keyword], [ac_cv_c_restrict],
329  [ac_cv_c_restrict=no
330   # The order here caters to the fact that C++ does not require restrict.
331   for ac_kw in __restrict __restrict__ _Restrict restrict; do
332     AC_COMPILE_IFELSE(
333      [AC_LANG_PROGRAM(
334	 [[typedef int *int_ptr;
335	   int foo (int_ptr $ac_kw ip) { return ip[0]; }
336	   int bar (int [$ac_kw]); /* Catch GCC bug 14050.  */
337	   int bar (int ip[$ac_kw]) { return ip[0]; }
338	 ]],
339	 [[int s[1];
340	   int *$ac_kw t = s;
341	   t[0] = 0;
342	   return foo (t) + bar (t);
343	 ]])],
344      [ac_cv_c_restrict=$ac_kw])
345     test "$ac_cv_c_restrict" != no && break
346   done
347  ])
348 AH_VERBATIM([restrict],
349[/* Define to the equivalent of the C99 'restrict' keyword, or to
350   nothing if this is not supported.  Do not define if restrict is
351   supported directly.  */
352#undef restrict
353/* Work around a bug in Sun C++: it does not support _Restrict or
354   __restrict__, even though the corresponding Sun C compiler ends up with
355   "#define restrict _Restrict" or "#define restrict __restrict__" in the
356   previous line.  Perhaps some future version of Sun C++ will work with
357   restrict; if so, hopefully it defines __RESTRICT like Sun C does.  */
358#if defined __SUNPRO_CC && !defined __RESTRICT
359# define _Restrict
360# define __restrict__
361#endif])
362 case $ac_cv_c_restrict in
363   restrict) ;;
364   no) AC_DEFINE([restrict], []) ;;
365   *)  AC_DEFINE_UNQUOTED([restrict], [$ac_cv_c_restrict]) ;;
366 esac
367])# AC_C_RESTRICT
368
369# gl_BIGENDIAN
370# is like AC_C_BIGENDIAN, except that it can be AC_REQUIREd.
371# Note that AC_REQUIRE([AC_C_BIGENDIAN]) does not work reliably because some
372# macros invoke AC_C_BIGENDIAN with arguments.
373AC_DEFUN([gl_BIGENDIAN],
374[
375  AC_C_BIGENDIAN
376])
377
378# gl_CACHE_VAL_SILENT(cache-id, command-to-set-it)
379# is like AC_CACHE_VAL(cache-id, command-to-set-it), except that it does not
380# output a spurious "(cached)" mark in the midst of other configure output.
381# This macro should be used instead of AC_CACHE_VAL when it is not surrounded
382# by an AC_MSG_CHECKING/AC_MSG_RESULT pair.
383AC_DEFUN([gl_CACHE_VAL_SILENT],
384[
385  saved_as_echo_n="$as_echo_n"
386  as_echo_n=':'
387  AC_CACHE_VAL([$1], [$2])
388  as_echo_n="$saved_as_echo_n"
389])
390
391# AS_VAR_COPY was added in autoconf 2.63b
392m4_define_default([AS_VAR_COPY],
393[AS_LITERAL_IF([$1[]$2], [$1=$$2], [eval $1=\$$2])])
394
395# AC_PROG_SED was added in autoconf 2.59b
396m4_ifndef([AC_PROG_SED],
397[AC_DEFUN([AC_PROG_SED],
398[AC_CACHE_CHECK([for a sed that does not truncate output], ac_cv_path_SED,
399    [dnl ac_script should not contain more than 99 commands (for HP-UX sed),
400     dnl but more than about 7000 bytes, to catch a limit in Solaris 8 /usr/ucb/sed.
401     ac_script=s/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb/
402     for ac_i in 1 2 3 4 5 6 7; do
403       ac_script="$ac_script$as_nl$ac_script"
404     done
405     echo "$ac_script" 2>/dev/null | sed 99q >conftest.sed
406     AS_UNSET([ac_script])
407     if test -z "$SED"; then
408       ac_path_SED_found=false
409       _AS_PATH_WALK([], [
410         for ac_prog in sed gsed; do
411           for ac_exec_ext in '' $ac_executable_extensions; do
412             ac_path_SED="$as_dir/$ac_prog$ac_exec_ext"
413             AS_EXECUTABLE_P(["$ac_path_SED"]) || continue
414             case `"$ac_path_SED" --version 2>&1` in
415               *GNU*) ac_cv_path_SED=$ac_path_SED ac_path_SED_found=:;;
416               *)
417                 ac_count=0
418                 _AS_ECHO_N([0123456789]) >conftest.in
419                 while :
420                 do
421                   cat conftest.in conftest.in >conftest.tmp
422                   mv conftest.tmp conftest.in
423                   cp conftest.in conftest.nl
424                   echo >> conftest.nl
425                   "$ac_path_SED" -f conftest.sed <conftest.nl >conftest.out 2>/dev/null || break
426                   diff conftest.out conftest.nl >/dev/null 2>&1 || break
427                   ac_count=`expr $ac_count + 1`
428                   if test $ac_count -gt ${ac_path_SED_max-0}; then
429                     # Best so far, but keep looking for better
430                     ac_cv_path_SED=$ac_path_SED
431                     ac_path_SED_max=$ac_count
432                   fi
433                   test $ac_count -gt 10 && break
434                 done
435                 rm -f conftest.in conftest.tmp conftest.nl conftest.out;;
436             esac
437             $ac_path_SED_found && break 3
438           done
439         done])
440       if test -z "$ac_cv_path_SED"; then
441         AC_ERROR([no acceptable sed could be found in \$PATH])
442       fi
443     else
444       ac_cv_path_SED=$SED
445     fi
446 SED="$ac_cv_path_SED"
447 AC_SUBST([SED])dnl
448 rm -f conftest.sed
449])])])
450