1# gnulib-common.m4 serial 33
2dnl Copyright (C) 2007-2012 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/* The __pure__ attribute was added in gcc 2.96.  */
53#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
54# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
55#else
56# define _GL_ATTRIBUTE_PURE /* empty */
57#endif
58
59/* The __const__ attribute was added in gcc 2.95.  */
60#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 95)
61# define _GL_ATTRIBUTE_CONST __attribute__ ((__const__))
62#else
63# define _GL_ATTRIBUTE_CONST /* empty */
64#endif
65])
66  dnl Preparation for running test programs:
67  dnl Tell glibc to write diagnostics from -D_FORTIFY_SOURCE=2 to stderr, not
68  dnl to /dev/tty, so they can be redirected to log files.  Such diagnostics
69  dnl arise e.g., in the macros gl_PRINTF_DIRECTIVE_N, gl_SNPRINTF_DIRECTIVE_N.
70  LIBC_FATAL_STDERR_=1
71  export LIBC_FATAL_STDERR_
72])
73
74# gl_MODULE_INDICATOR_CONDITION
75# expands to a C preprocessor expression that evaluates to 1 or 0, depending
76# whether a gnulib module that has been requested shall be considered present
77# or not.
78m4_define([gl_MODULE_INDICATOR_CONDITION], [1])
79
80# gl_MODULE_INDICATOR_SET_VARIABLE([modulename])
81# sets the shell variable that indicates the presence of the given module to
82# a C preprocessor expression that will evaluate to 1.
83AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE],
84[
85  gl_MODULE_INDICATOR_SET_VARIABLE_AUX(
86    [GNULIB_[]m4_translit([[$1]],
87                          [abcdefghijklmnopqrstuvwxyz./-],
88                          [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])],
89    [gl_MODULE_INDICATOR_CONDITION])
90])
91
92# gl_MODULE_INDICATOR_SET_VARIABLE_AUX([variable])
93# modifies the shell variable to include the gl_MODULE_INDICATOR_CONDITION.
94# The shell variable's value is a C preprocessor expression that evaluates
95# to 0 or 1.
96AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX],
97[
98  m4_if(m4_defn([gl_MODULE_INDICATOR_CONDITION]), [1],
99    [
100     dnl Simplify the expression VALUE || 1 to 1.
101     $1=1
102    ],
103    [gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([$1],
104                                             [gl_MODULE_INDICATOR_CONDITION])])
105])
106
107# gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([variable], [condition])
108# modifies the shell variable to include the given condition.  The shell
109# variable's value is a C preprocessor expression that evaluates to 0 or 1.
110AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR],
111[
112  dnl Simplify the expression 1 || CONDITION to 1.
113  if test "$[]$1" != 1; then
114    dnl Simplify the expression 0 || CONDITION to CONDITION.
115    if test "$[]$1" = 0; then
116      $1=$2
117    else
118      $1="($[]$1 || $2)"
119    fi
120  fi
121])
122
123# gl_MODULE_INDICATOR([modulename])
124# defines a C macro indicating the presence of the given module
125# in a location where it can be used.
126#                                             |  Value  |   Value   |
127#                                             | in lib/ | in tests/ |
128# --------------------------------------------+---------+-----------+
129# Module present among main modules:          |    1    |     1     |
130# --------------------------------------------+---------+-----------+
131# Module present among tests-related modules: |    0    |     1     |
132# --------------------------------------------+---------+-----------+
133# Module not present at all:                  |    0    |     0     |
134# --------------------------------------------+---------+-----------+
135AC_DEFUN([gl_MODULE_INDICATOR],
136[
137  AC_DEFINE_UNQUOTED([GNULIB_]m4_translit([[$1]],
138      [abcdefghijklmnopqrstuvwxyz./-],
139      [ABCDEFGHIJKLMNOPQRSTUVWXYZ___]),
140    [gl_MODULE_INDICATOR_CONDITION],
141    [Define to a C preprocessor expression that evaluates to 1 or 0,
142     depending whether the gnulib module $1 shall be considered present.])
143])
144
145# gl_MODULE_INDICATOR_FOR_TESTS([modulename])
146# defines a C macro indicating the presence of the given module
147# in lib or tests. This is useful to determine whether the module
148# should be tested.
149#                                             |  Value  |   Value   |
150#                                             | in lib/ | in tests/ |
151# --------------------------------------------+---------+-----------+
152# Module present among main modules:          |    1    |     1     |
153# --------------------------------------------+---------+-----------+
154# Module present among tests-related modules: |    1    |     1     |
155# --------------------------------------------+---------+-----------+
156# Module not present at all:                  |    0    |     0     |
157# --------------------------------------------+---------+-----------+
158AC_DEFUN([gl_MODULE_INDICATOR_FOR_TESTS],
159[
160  AC_DEFINE([GNULIB_TEST_]m4_translit([[$1]],
161      [abcdefghijklmnopqrstuvwxyz./-],
162      [ABCDEFGHIJKLMNOPQRSTUVWXYZ___]), [1],
163    [Define to 1 when the gnulib module $1 should be tested.])
164])
165
166# gl_ASSERT_NO_GNULIB_POSIXCHECK
167# asserts that there will never be a need to #define GNULIB_POSIXCHECK.
168# and thereby enables an optimization of configure and config.h.
169# Used by Emacs.
170AC_DEFUN([gl_ASSERT_NO_GNULIB_POSIXCHECK],
171[
172  dnl Override gl_WARN_ON_USE_PREPARE.
173  dnl But hide this definition from 'aclocal'.
174  AC_DEFUN([gl_W][ARN_ON_USE_PREPARE], [])
175])
176
177# gl_ASSERT_NO_GNULIB_TESTS
178# asserts that there will be no gnulib tests in the scope of the configure.ac
179# and thereby enables an optimization of config.h.
180# Used by Emacs.
181AC_DEFUN([gl_ASSERT_NO_GNULIB_TESTS],
182[
183  dnl Override gl_MODULE_INDICATOR_FOR_TESTS.
184  AC_DEFUN([gl_MODULE_INDICATOR_FOR_TESTS], [])
185])
186
187# Test whether <features.h> exists.
188# Set HAVE_FEATURES_H.
189AC_DEFUN([gl_FEATURES_H],
190[
191  AC_CHECK_HEADERS_ONCE([features.h])
192  if test $ac_cv_header_features_h = yes; then
193    HAVE_FEATURES_H=1
194  else
195    HAVE_FEATURES_H=0
196  fi
197  AC_SUBST([HAVE_FEATURES_H])
198])
199
200# m4_foreach_w
201# is a backport of autoconf-2.59c's m4_foreach_w.
202# Remove this macro when we can assume autoconf >= 2.60.
203m4_ifndef([m4_foreach_w],
204  [m4_define([m4_foreach_w],
205    [m4_foreach([$1], m4_split(m4_normalize([$2]), [ ]), [$3])])])
206
207# AS_VAR_IF(VAR, VALUE, [IF-MATCH], [IF-NOT-MATCH])
208# ----------------------------------------------------
209# Backport of autoconf-2.63b's macro.
210# Remove this macro when we can assume autoconf >= 2.64.
211m4_ifndef([AS_VAR_IF],
212[m4_define([AS_VAR_IF],
213[AS_IF([test x"AS_VAR_GET([$1])" = x""$2], [$3], [$4])])])
214
215# gl_PROG_CC_C99
216# Modifies the value of the shell variable CC in an attempt to make $CC
217# understand ISO C99 source code.
218# This is like AC_PROG_CC_C99, except that
219# - AC_PROG_CC_C99 did not exist in Autoconf versions < 2.60,
220# - AC_PROG_CC_C99 does not mix well with AC_PROG_CC_STDC
221#   <http://lists.gnu.org/archive/html/bug-gnulib/2011-09/msg00367.html>,
222#   but many more packages use AC_PROG_CC_STDC than AC_PROG_CC_C99
223#   <http://lists.gnu.org/archive/html/bug-gnulib/2011-09/msg00441.html>.
224# Remaining problems:
225# - When AC_PROG_CC_STDC is invoked twice, it adds the C99 enabling options
226#   to CC twice
227#   <http://lists.gnu.org/archive/html/bug-gnulib/2011-09/msg00431.html>.
228# - AC_PROG_CC_STDC is likely to change now that C11 is an ISO standard.
229AC_DEFUN([gl_PROG_CC_C99],
230[
231  dnl Change that version number to the minimum Autoconf version that supports
232  dnl mixing AC_PROG_CC_C99 calls with AC_PROG_CC_STDC calls.
233  m4_version_prereq([9.0],
234    [AC_REQUIRE([AC_PROG_CC_C99])],
235    [AC_REQUIRE([AC_PROG_CC_STDC])])
236])
237
238# gl_PROG_AR_RANLIB
239# Determines the values for AR, ARFLAGS, RANLIB that fit with the compiler.
240# The user can set the variables AR, ARFLAGS, RANLIB if he wants to override
241# the values.
242AC_DEFUN([gl_PROG_AR_RANLIB],
243[
244  dnl Minix 3 comes with two toolchains: The Amsterdam Compiler Kit compiler
245  dnl as "cc", and GCC as "gcc". They have different object file formats and
246  dnl library formats. In particular, the GNU binutils programs ar, ranlib
247  dnl produce libraries that work only with gcc, not with cc.
248  AC_REQUIRE([AC_PROG_CC])
249  AC_CACHE_CHECK([for Minix Amsterdam compiler], [gl_cv_c_amsterdam_compiler],
250    [
251      AC_EGREP_CPP([Amsterdam],
252        [
253#ifdef __ACK__
254Amsterdam
255#endif
256        ],
257        [gl_cv_c_amsterdam_compiler=yes],
258        [gl_cv_c_amsterdam_compiler=no])
259    ])
260  if test -z "$AR"; then
261    if test $gl_cv_c_amsterdam_compiler = yes; then
262      AR='cc -c.a'
263      if test -z "$ARFLAGS"; then
264        ARFLAGS='-o'
265      fi
266    else
267      dnl Use the Automake-documented default values for AR and ARFLAGS,
268      dnl but prefer ${host}-ar over ar (useful for cross-compiling).
269      AC_CHECK_TOOL([AR], [ar], [ar])
270      if test -z "$ARFLAGS"; then
271        ARFLAGS='cru'
272      fi
273    fi
274  else
275    if test -z "$ARFLAGS"; then
276      ARFLAGS='cru'
277    fi
278  fi
279  AC_SUBST([AR])
280  AC_SUBST([ARFLAGS])
281  if test -z "$RANLIB"; then
282    if test $gl_cv_c_amsterdam_compiler = yes; then
283      RANLIB=':'
284    else
285      dnl Use the ranlib program if it is available.
286      AC_PROG_RANLIB
287    fi
288  fi
289  AC_SUBST([RANLIB])
290])
291
292# AC_PROG_MKDIR_P
293# is a backport of autoconf-2.60's AC_PROG_MKDIR_P, with a fix
294# for interoperability with automake-1.9.6 from autoconf-2.62.
295# Remove this macro when we can assume autoconf >= 2.62 or
296# autoconf >= 2.60 && automake >= 1.10.
297m4_ifdef([AC_PROG_MKDIR_P], [
298  dnl For automake-1.9.6 && autoconf < 2.62: Ensure MKDIR_P is AC_SUBSTed.
299  m4_define([AC_PROG_MKDIR_P],
300    m4_defn([AC_PROG_MKDIR_P])[
301    AC_SUBST([MKDIR_P])])], [
302  dnl For autoconf < 2.60: Backport of AC_PROG_MKDIR_P.
303  AC_DEFUN_ONCE([AC_PROG_MKDIR_P],
304    [AC_REQUIRE([AM_PROG_MKDIR_P])dnl defined by automake
305     MKDIR_P='$(mkdir_p)'
306     AC_SUBST([MKDIR_P])])])
307
308# AC_C_RESTRICT
309# This definition overrides the AC_C_RESTRICT macro from autoconf 2.60..2.61,
310# so that mixed use of GNU C and GNU C++ and mixed use of Sun C and Sun C++
311# works.
312# This definition can be removed once autoconf >= 2.62 can be assumed.
313m4_if(m4_version_compare(m4_defn([m4_PACKAGE_VERSION]),[2.62]),[-1],[
314AC_DEFUN([AC_C_RESTRICT],
315[AC_CACHE_CHECK([for C/C++ restrict keyword], [ac_cv_c_restrict],
316  [ac_cv_c_restrict=no
317   # The order here caters to the fact that C++ does not require restrict.
318   for ac_kw in __restrict __restrict__ _Restrict restrict; do
319     AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
320      [[typedef int * int_ptr;
321        int foo (int_ptr $ac_kw ip) {
322        return ip[0];
323       }]],
324      [[int s[1];
325        int * $ac_kw t = s;
326        t[0] = 0;
327        return foo(t)]])],
328      [ac_cv_c_restrict=$ac_kw])
329     test "$ac_cv_c_restrict" != no && break
330   done
331  ])
332 AH_VERBATIM([restrict],
333[/* Define to the equivalent of the C99 'restrict' keyword, or to
334   nothing if this is not supported.  Do not define if restrict is
335   supported directly.  */
336#undef restrict
337/* Work around a bug in Sun C++: it does not support _Restrict, even
338   though the corresponding Sun C compiler does, which causes
339   "#define restrict _Restrict" in the previous line.  Perhaps some future
340   version of Sun C++ will work with _Restrict; if so, it'll probably
341   define __RESTRICT, just as Sun C does.  */
342#if defined __SUNPRO_CC && !defined __RESTRICT
343# define _Restrict
344#endif])
345 case $ac_cv_c_restrict in
346   restrict) ;;
347   no) AC_DEFINE([restrict], []) ;;
348   *)  AC_DEFINE_UNQUOTED([restrict], [$ac_cv_c_restrict]) ;;
349 esac
350])
351])
352
353# gl_BIGENDIAN
354# is like AC_C_BIGENDIAN, except that it can be AC_REQUIREd.
355# Note that AC_REQUIRE([AC_C_BIGENDIAN]) does not work reliably because some
356# macros invoke AC_C_BIGENDIAN with arguments.
357AC_DEFUN([gl_BIGENDIAN],
358[
359  AC_C_BIGENDIAN
360])
361
362# gl_CACHE_VAL_SILENT(cache-id, command-to-set-it)
363# is like AC_CACHE_VAL(cache-id, command-to-set-it), except that it does not
364# output a spurious "(cached)" mark in the midst of other configure output.
365# This macro should be used instead of AC_CACHE_VAL when it is not surrounded
366# by an AC_MSG_CHECKING/AC_MSG_RESULT pair.
367AC_DEFUN([gl_CACHE_VAL_SILENT],
368[
369  saved_as_echo_n="$as_echo_n"
370  as_echo_n=':'
371  AC_CACHE_VAL([$1], [$2])
372  as_echo_n="$saved_as_echo_n"
373])
374