1 # gnulib-common.m4 serial 50
2 dnl Copyright (C) 2007-2020 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.
10 # is expanded unconditionally through gnulib-tool magic.
11 AC_DEFUN([gl_COMMON], [
12 dnl Use AC_REQUIRE here, so that the code is expanded once only.
13 AC_REQUIRE([gl_00GNULIB])
14 AC_REQUIRE([gl_COMMON_BODY])
15 AC_REQUIRE([gl_ZZGNULIB])
17 AC_DEFUN([gl_COMMON_BODY], [
18 AH_VERBATIM([_GL_GNUC_PREREQ],
19 [/* True if the compiler says it groks GNU C version MAJOR.MINOR. */
20 #if defined __GNUC__ && defined __GNUC_MINOR__
21 # define _GL_GNUC_PREREQ(major, minor) \
22 ((major) < __GNUC__ + ((minor) <= __GNUC_MINOR__))
24 # define _GL_GNUC_PREREQ(major, minor) 0
27 AH_VERBATIM([_Noreturn],
28 [/* The _Noreturn keyword of C11. */
30 # if (defined __cplusplus \
31 && ((201103 <= __cplusplus && !(__GNUC__ == 4 && __GNUC_MINOR__ == 7)) \
32 || (defined _MSC_VER && 1900 <= _MSC_VER)) \
34 /* [[noreturn]] is not practically usable, because with it the syntax
35 extern _Noreturn void func (...);
36 would not be valid; such a declaration would only be valid with 'extern'
37 and '_Noreturn' swapped, or without the 'extern' keyword. However, some
38 AIX system header files and several gnulib header files use precisely
39 this syntax with 'extern'. */
40 # define _Noreturn [[noreturn]]
41 # elif ((!defined __cplusplus || defined __clang__) \
42 && (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) \
43 || _GL_GNUC_PREREQ (4, 7) \
44 || (defined __apple_build_version__ \
45 ? 6000000 <= __apple_build_version__ \
46 : 3 < __clang_major__ + (5 <= __clang_minor__))))
47 /* _Noreturn works as-is. */
48 # elif _GL_GNUC_PREREQ (2, 8) || 0x5110 <= __SUNPRO_C
49 # define _Noreturn __attribute__ ((__noreturn__))
50 # elif 1200 <= (defined _MSC_VER ? _MSC_VER : 0)
51 # define _Noreturn __declspec (noreturn)
57 AH_VERBATIM([isoc99_inline],
58 [/* Work around a bug in Apple GCC 4.0.1 build 5465: In C99 mode, it supports
59 the ISO C 99 semantics of 'extern inline' (unlike the GNU C semantics of
60 earlier versions), but does not display it by setting __GNUC_STDC_INLINE__.
61 __APPLE__ && __MACH__ test for Mac OS X.
62 __APPLE_CC__ tests for the Apple compiler and its version.
63 __STDC_VERSION__ tests for the C99 mode. */
64 #if defined __APPLE__ && defined __MACH__ && __APPLE_CC__ >= 5465 && !defined __cplusplus && __STDC_VERSION__ >= 199901L && !defined __GNUC_STDC_INLINE__
65 # define __GNUC_STDC_INLINE__ 1
67 AH_VERBATIM([attribute],
69 #ifdef __has_attribute
70 # define _GL_HAS_ATTRIBUTE(attr) __has_attribute (__##attr##__)
72 # define _GL_HAS_ATTRIBUTE(attr) _GL_ATTR_##attr
73 # define _GL_ATTR_alloc_size _GL_GNUC_PREREQ (4, 3)
74 # define _GL_ATTR_always_inline _GL_GNUC_PREREQ (3, 2)
75 # define _GL_ATTR_artificial _GL_GNUC_PREREQ (4, 3)
76 # define _GL_ATTR_cold _GL_GNUC_PREREQ (4, 3)
77 # define _GL_ATTR_const _GL_GNUC_PREREQ (2, 95)
78 # define _GL_ATTR_deprecated _GL_GNUC_PREREQ (3, 1)
79 # define _GL_ATTR_error _GL_GNUC_PREREQ (4, 3)
80 # define _GL_ATTR_externally_visible _GL_GNUC_PREREQ (4, 1)
81 # define _GL_ATTR_fallthrough _GL_GNUC_PREREQ (7, 0)
82 # define _GL_ATTR_format _GL_GNUC_PREREQ (2, 7)
83 # define _GL_ATTR_leaf _GL_GNUC_PREREQ (4, 6)
85 # define _GL_ATTR_may_alias 0
87 # define _GL_ATTR_may_alias _GL_GNUC_PREREQ (3, 3)
89 # define _GL_ATTR_malloc _GL_GNUC_PREREQ (3, 0)
90 # define _GL_ATTR_noinline _GL_GNUC_PREREQ (3, 1)
91 # define _GL_ATTR_nonnull _GL_GNUC_PREREQ (3, 3)
92 # define _GL_ATTR_nonstring _GL_GNUC_PREREQ (8, 0)
93 # define _GL_ATTR_nothrow _GL_GNUC_PREREQ (3, 3)
94 # define _GL_ATTR_packed _GL_GNUC_PREREQ (2, 7)
95 # define _GL_ATTR_pure _GL_GNUC_PREREQ (2, 96)
96 # define _GL_ATTR_returns_nonnull _GL_GNUC_PREREQ (4, 9)
97 # define _GL_ATTR_sentinel _GL_GNUC_PREREQ (4, 0)
98 # define _GL_ATTR_unused _GL_GNUC_PREREQ (2, 7)
99 # define _GL_ATTR_warn_unused_result _GL_GNUC_PREREQ (3, 4)
102 ]dnl There is no _GL_ATTRIBUTE_ALIGNED; use stdalign's _Alignas instead.
104 #if _GL_HAS_ATTRIBUTE (alloc_size)
105 # define _GL_ATTRIBUTE_ALLOC_SIZE(args) __attribute__ ((__alloc_size__ args))
107 # define _GL_ATTRIBUTE_ALLOC_SIZE(args)
110 #if _GL_HAS_ATTRIBUTE (always_inline)
111 # define _GL_ATTRIBUTE_ALWAYS_INLINE __attribute__ ((__always_inline__))
113 # define _GL_ATTRIBUTE_ALWAYS_INLINE
116 #if _GL_HAS_ATTRIBUTE (artificial)
117 # define _GL_ATTRIBUTE_ARTIFICIAL __attribute__ ((__artificial__))
119 # define _GL_ATTRIBUTE_ARTIFICIAL
122 /* Avoid __attribute__ ((cold)) on MinGW; see thread starting at
123 <https://lists.gnu.org/r/emacs-devel/2019-04/msg01152.html>. */
124 #if _GL_HAS_ATTRIBUTE (cold) && !defined __MINGW32__
125 # define _GL_ATTRIBUTE_COLD __attribute__ ((__cold__))
127 # define _GL_ATTRIBUTE_COLD
130 #if _GL_HAS_ATTRIBUTE (const)
131 # define _GL_ATTRIBUTE_CONST __attribute__ ((__const__))
133 # define _GL_ATTRIBUTE_CONST
136 #if 201710L < __STDC_VERSION__
137 # define _GL_ATTRIBUTE_DEPRECATED [[__deprecated__]]
138 #elif _GL_HAS_ATTRIBUTE (deprecated)
139 # define _GL_ATTRIBUTE_DEPRECATED __attribute__ ((__deprecated__))
141 # define _GL_ATTRIBUTE_DEPRECATED
144 #if _GL_HAS_ATTRIBUTE (error)
145 # define _GL_ATTRIBUTE_ERROR(msg) __attribute__ ((__error__ (msg)))
146 # define _GL_ATTRIBUTE_WARNING(msg) __attribute__ ((__warning__ (msg)))
148 # define _GL_ATTRIBUTE_ERROR(msg)
149 # define _GL_ATTRIBUTE_WARNING(msg)
152 #if _GL_HAS_ATTRIBUTE (externally_visible)
153 # define _GL_ATTRIBUTE_EXTERNALLY_VISIBLE __attribute__ ((externally_visible))
155 # define _GL_ATTRIBUTE_EXTERNALLY_VISIBLE
158 /* FALLTHROUGH is special, because it always expands to something. */
159 #if 201710L < __STDC_VERSION__
160 # define _GL_ATTRIBUTE_FALLTHROUGH [[__fallthrough__]]
161 #elif _GL_HAS_ATTRIBUTE (fallthrough)
162 # define _GL_ATTRIBUTE_FALLTHROUGH __attribute__ ((__fallthrough__))
164 # define _GL_ATTRIBUTE_FALLTHROUGH ((void) 0)
167 #if _GL_HAS_ATTRIBUTE (format)
168 # define _GL_ATTRIBUTE_FORMAT(spec) __attribute__ ((__format__ spec))
170 # define _GL_ATTRIBUTE_FORMAT(spec)
173 #if _GL_HAS_ATTRIBUTE (leaf)
174 # define _GL_ATTRIBUTE_LEAF __attribute__ ((__leaf__))
176 # define _GL_ATTRIBUTE_LEAF
179 #if _GL_HAS_ATTRIBUTE (may_alias)
180 # define _GL_ATTRIBUTE_MAY_ALIAS __attribute__ ((__may_alias__))
182 # define _GL_ATTRIBUTE_MAY_ALIAS
185 #if 201710L < __STDC_VERSION__
186 # define _GL_ATTRIBUTE_MAYBE_UNUSED [[__maybe_unused__]]
187 #elif _GL_HAS_ATTRIBUTE (unused)
188 # define _GL_ATTRIBUTE_MAYBE_UNUSED __attribute__ ((__unused__))
190 # define _GL_ATTRIBUTE_MAYBE_UNUSED
192 /* Earlier spellings of this macro. */
193 #define _GL_UNUSED _GL_ATTRIBUTE_MAYBE_UNUSED
194 #define _UNUSED_PARAMETER_ _GL_ATTRIBUTE_MAYBE_UNUSED
196 #if _GL_HAS_ATTRIBUTE (malloc)
197 # define _GL_ATTRIBUTE_MALLOC __attribute__ ((__malloc__))
199 # define _GL_ATTRIBUTE_MALLOC
202 #if 201710L < __STDC_VERSION__
203 # define _GL_ATTRIBUTE_NODISCARD [[__nodiscard__]]
204 #elif _GL_HAS_ATTRIBUTE (warn_unused_result)
205 # define _GL_ATTRIBUTE_NODISCARD __attribute__ ((__warn_unused_result__))
207 # define _GL_ATTRIBUTE_NODISCARD
210 #if _GL_HAS_ATTRIBUTE (noinline)
211 # define _GL_ATTRIBUTE_NOINLINE __attribute__ ((__noinline__))
213 # define _GL_ATTRIBUTE_NOINLINE
216 #if _GL_HAS_ATTRIBUTE (nonnull)
217 # define _GL_ATTRIBUTE_NONNULL(args) __attribute__ ((__nonnull__ args))
219 # define _GL_ATTRIBUTE_NONNULL(args)
222 #if _GL_HAS_ATTRIBUTE (nonstring)
223 # define _GL_ATTRIBUTE_NONSTRING __attribute__ ((__nonstring__))
225 # define _GL_ATTRIBUTE_NONSTRING
228 /* There is no _GL_ATTRIBUTE_NORETURN; use _Noreturn instead. */
230 #if _GL_HAS_ATTRIBUTE (nothrow) && !defined __cplusplus
231 # define _GL_ATTRIBUTE_NOTHROW __attribute__ ((__nothrow__))
233 # define _GL_ATTRIBUTE_NOTHROW
236 #if _GL_HAS_ATTRIBUTE (packed)
237 # define _GL_ATTRIBUTE_PACKED __attribute__ ((__packed__))
239 # define _GL_ATTRIBUTE_PACKED
242 #if _GL_HAS_ATTRIBUTE (pure)
243 # define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
245 # define _GL_ATTRIBUTE_PURE
248 #if _GL_HAS_ATTRIBUTE (returns_nonnull)
249 # define _GL_ATTRIBUTE_RETURNS_NONNULL __attribute__ ((__returns_nonnull__))
251 # define _GL_ATTRIBUTE_RETURNS_NONNULL
254 #if _GL_HAS_ATTRIBUTE (sentinel)
255 # define _GL_ATTRIBUTE_SENTINEL(pos) __attribute__ ((__sentinel__ pos))
257 # define _GL_ATTRIBUTE_SENTINEL(pos)
260 ]dnl There is no _GL_ATTRIBUTE_VISIBILITY; see m4/visibility.m4 instead.
262 /* To support C++ as well as C, use _GL_UNUSED_LABEL with trailing ';'. */
263 #if !defined __cplusplus || _GL_GNUC_PREREQ (4, 5)
264 # define _GL_UNUSED_LABEL _GL_ATTRIBUTE_MAYBE_UNUSED
266 # define _GL_UNUSED_LABEL
269 AH_VERBATIM([async_safe],
270 [/* The _GL_ASYNC_SAFE marker should be attached to functions that are
271 signal handlers (for signals other than SIGABRT, SIGPIPE) or can be
272 invoked from such signal handlers. Such functions have some restrictions:
273 * All functions that it calls should be marked _GL_ASYNC_SAFE as well,
274 or should be listed as async-signal-safe in POSIX
275 <https://pubs.opengroup.org/onlinepubs/9699919799/functions/V2_chap02.html#tag_15_04>
276 section 2.4.3. Note that malloc(), sprintf(), and fwrite(), in
277 particular, are NOT async-signal-safe.
278 * All memory locations (variables and struct fields) that these functions
279 access must be marked 'volatile'. This holds for both read and write
280 accesses. Otherwise the compiler might optimize away stores to and
281 reads from such locations that occur in the program, depending on its
282 data flow analysis. For example, when the program contains a loop
283 that is intended to inspect a variable set from within a signal handler
284 while (!signal_occurred)
286 the compiler is allowed to transform this into an endless loop if the
287 variable 'signal_occurred' is not declared 'volatile'.
288 Additionally, recall that:
289 * A signal handler should not modify errno (except if it is a handler
290 for a fatal signal and ends by raising the same signal again, thus
291 provoking the termination of the process). If it invokes a function
292 that may clobber errno, it needs to save and restore the value of
294 #define _GL_ASYNC_SAFE
296 dnl Hint which direction to take regarding cross-compilation guesses:
297 dnl When a user installs a program on a platform they are not intimately
298 dnl familiar with, --enable-cross-guesses=conservative is the appropriate
299 dnl choice. It implements the "If we don't know, assume the worst" principle.
300 dnl However, when an operating system developer (on a platform which is not
301 dnl yet known to gnulib) builds packages for their platform, they want to
302 dnl expose, not hide, possible platform bugs; in this case,
303 dnl --enable-cross-guesses=risky is the appropriate choice.
304 dnl Sets the variables
305 dnl gl_cross_guess_normal (to be used when 'yes' is good and 'no' is bad),
306 dnl gl_cross_guess_inverted (to be used when 'no' is good and 'yes' is bad).
307 AC_ARG_ENABLE([cross-guesses],
308 [AS_HELP_STRING([--enable-cross-guesses={conservative|risky}],
309 [specify policy for cross-compilation guesses])],
310 [if test "x$enableval" != xconservative && test "x$enableval" != xrisky; then
311 AC_MSG_WARN([invalid argument supplied to --enable-cross-guesses])
312 enableval=conservative
314 gl_cross_guesses="$enableval"],
315 [gl_cross_guesses=conservative])
316 if test $gl_cross_guesses = risky; then
317 gl_cross_guess_normal="guessing yes"
318 gl_cross_guess_inverted="guessing no"
320 gl_cross_guess_normal="guessing no"
321 gl_cross_guess_inverted="guessing yes"
323 dnl Preparation for running test programs:
324 dnl Tell glibc to write diagnostics from -D_FORTIFY_SOURCE=2 to stderr, not
325 dnl to /dev/tty, so they can be redirected to log files. Such diagnostics
326 dnl arise e.g., in the macros gl_PRINTF_DIRECTIVE_N, gl_SNPRINTF_DIRECTIVE_N.
328 export LIBC_FATAL_STDERR_
331 # gl_MODULE_INDICATOR_CONDITION
332 # expands to a C preprocessor expression that evaluates to 1 or 0, depending
333 # whether a gnulib module that has been requested shall be considered present
335 m4_define([gl_MODULE_INDICATOR_CONDITION], [1])
337 # gl_MODULE_INDICATOR_SET_VARIABLE([modulename])
338 # sets the shell variable that indicates the presence of the given module to
339 # a C preprocessor expression that will evaluate to 1.
340 AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE],
342 gl_MODULE_INDICATOR_SET_VARIABLE_AUX(
343 [GNULIB_[]m4_translit([[$1]],
344 [abcdefghijklmnopqrstuvwxyz./-],
345 [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])],
346 [gl_MODULE_INDICATOR_CONDITION])
349 # gl_MODULE_INDICATOR_SET_VARIABLE_AUX([variable])
350 # modifies the shell variable to include the gl_MODULE_INDICATOR_CONDITION.
351 # The shell variable's value is a C preprocessor expression that evaluates
353 AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX],
355 m4_if(m4_defn([gl_MODULE_INDICATOR_CONDITION]), [1],
357 dnl Simplify the expression VALUE || 1 to 1.
360 [gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([$1],
361 [gl_MODULE_INDICATOR_CONDITION])])
364 # gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([variable], [condition])
365 # modifies the shell variable to include the given condition. The shell
366 # variable's value is a C preprocessor expression that evaluates to 0 or 1.
367 AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR],
369 dnl Simplify the expression 1 || CONDITION to 1.
370 if test "$[]$1" != 1; then
371 dnl Simplify the expression 0 || CONDITION to CONDITION.
372 if test "$[]$1" = 0; then
380 # gl_MODULE_INDICATOR([modulename])
381 # defines a C macro indicating the presence of the given module
382 # in a location where it can be used.
384 # | in lib/ | in tests/ |
385 # --------------------------------------------+---------+-----------+
386 # Module present among main modules: | 1 | 1 |
387 # --------------------------------------------+---------+-----------+
388 # Module present among tests-related modules: | 0 | 1 |
389 # --------------------------------------------+---------+-----------+
390 # Module not present at all: | 0 | 0 |
391 # --------------------------------------------+---------+-----------+
392 AC_DEFUN([gl_MODULE_INDICATOR],
394 AC_DEFINE_UNQUOTED([GNULIB_]m4_translit([[$1]],
395 [abcdefghijklmnopqrstuvwxyz./-],
396 [ABCDEFGHIJKLMNOPQRSTUVWXYZ___]),
397 [gl_MODULE_INDICATOR_CONDITION],
398 [Define to a C preprocessor expression that evaluates to 1 or 0,
399 depending whether the gnulib module $1 shall be considered present.])
402 # gl_MODULE_INDICATOR_FOR_TESTS([modulename])
403 # defines a C macro indicating the presence of the given module
404 # in lib or tests. This is useful to determine whether the module
407 # | in lib/ | in tests/ |
408 # --------------------------------------------+---------+-----------+
409 # Module present among main modules: | 1 | 1 |
410 # --------------------------------------------+---------+-----------+
411 # Module present among tests-related modules: | 1 | 1 |
412 # --------------------------------------------+---------+-----------+
413 # Module not present at all: | 0 | 0 |
414 # --------------------------------------------+---------+-----------+
415 AC_DEFUN([gl_MODULE_INDICATOR_FOR_TESTS],
417 AC_DEFINE([GNULIB_TEST_]m4_translit([[$1]],
418 [abcdefghijklmnopqrstuvwxyz./-],
419 [ABCDEFGHIJKLMNOPQRSTUVWXYZ___]), [1],
420 [Define to 1 when the gnulib module $1 should be tested.])
423 # gl_ASSERT_NO_GNULIB_POSIXCHECK
424 # asserts that there will never be a need to #define GNULIB_POSIXCHECK.
425 # and thereby enables an optimization of configure and config.h.
427 AC_DEFUN([gl_ASSERT_NO_GNULIB_POSIXCHECK],
429 dnl Override gl_WARN_ON_USE_PREPARE.
430 dnl But hide this definition from 'aclocal'.
431 AC_DEFUN([gl_W][ARN_ON_USE_PREPARE], [])
434 # gl_ASSERT_NO_GNULIB_TESTS
435 # asserts that there will be no gnulib tests in the scope of the configure.ac
436 # and thereby enables an optimization of config.h.
438 AC_DEFUN([gl_ASSERT_NO_GNULIB_TESTS],
440 dnl Override gl_MODULE_INDICATOR_FOR_TESTS.
441 AC_DEFUN([gl_MODULE_INDICATOR_FOR_TESTS], [])
444 # Test whether <features.h> exists.
445 # Set HAVE_FEATURES_H.
446 AC_DEFUN([gl_FEATURES_H],
448 AC_CHECK_HEADERS_ONCE([features.h])
449 if test $ac_cv_header_features_h = yes; then
454 AC_SUBST([HAVE_FEATURES_H])
457 # AS_VAR_IF(VAR, VALUE, [IF-MATCH], [IF-NOT-MATCH])
458 # ----------------------------------------------------
459 # Backport of autoconf-2.63b's macro.
460 # Remove this macro when we can assume autoconf >= 2.64.
461 m4_ifndef([AS_VAR_IF],
462 [m4_define([AS_VAR_IF],
463 [AS_IF([test x"AS_VAR_GET([$1])" = x""$2], [$3], [$4])])])
466 # Modifies the value of the shell variable CC in an attempt to make $CC
467 # understand ISO C99 source code.
468 # This is like AC_PROG_CC_C99, except that
469 # - AC_PROG_CC_C99 does not mix well with AC_PROG_CC_STDC
470 # <https://lists.gnu.org/r/bug-gnulib/2011-09/msg00367.html>,
471 # but many more packages use AC_PROG_CC_STDC than AC_PROG_CC_C99
472 # <https://lists.gnu.org/r/bug-gnulib/2011-09/msg00441.html>.
473 # Remaining problems:
474 # - When AC_PROG_CC_STDC is invoked twice, it adds the C99 enabling options
476 # <https://lists.gnu.org/r/bug-gnulib/2011-09/msg00431.html>.
477 # - AC_PROG_CC_STDC is likely to change now that C11 is an ISO standard.
478 AC_DEFUN([gl_PROG_CC_C99],
480 dnl Change that version number to the minimum Autoconf version that supports
481 dnl mixing AC_PROG_CC_C99 calls with AC_PROG_CC_STDC calls.
482 m4_version_prereq([9.0],
483 [AC_REQUIRE([AC_PROG_CC_C99])],
484 [AC_REQUIRE([AC_PROG_CC_STDC])])
488 # Determines the values for AR, ARFLAGS, RANLIB that fit with the compiler.
489 # The user can set the variables AR, ARFLAGS, RANLIB if he wants to override
491 AC_DEFUN([gl_PROG_AR_RANLIB],
493 dnl Minix 3 comes with two toolchains: The Amsterdam Compiler Kit compiler
494 dnl as "cc", and GCC as "gcc". They have different object file formats and
495 dnl library formats. In particular, the GNU binutils programs ar and ranlib
496 dnl produce libraries that work only with gcc, not with cc.
497 AC_REQUIRE([AC_PROG_CC])
498 dnl The '][' hides this use from 'aclocal'.
499 AC_BEFORE([$0], [A][M_PROG_AR])
500 AC_CACHE_CHECK([for Minix Amsterdam compiler], [gl_cv_c_amsterdam_compiler],
502 AC_EGREP_CPP([Amsterdam],
508 [gl_cv_c_amsterdam_compiler=yes],
509 [gl_cv_c_amsterdam_compiler=no])
512 dnl Don't compete with AM_PROG_AR's decision about AR/ARFLAGS if we are not
513 dnl building with __ACK__.
514 if test $gl_cv_c_amsterdam_compiler = yes; then
515 if test -z "$AR"; then
518 if test -z "$ARFLAGS"; then
522 dnl AM_PROG_AR was added in automake v1.11.2. AM_PROG_AR does not AC_SUBST
523 dnl ARFLAGS variable (it is filed into Makefile.in directly by automake
524 dnl script on-demand, if not specified by ./configure of course).
525 dnl Don't AC_REQUIRE the AM_PROG_AR otherwise the code for __ACK__ above
526 dnl will be ignored. Also, pay attention to call AM_PROG_AR in else block
527 dnl because AM_PROG_AR is written so it could re-set AR variable even for
528 dnl __ACK__. It may seem like its easier to avoid calling the macro here,
529 dnl but we need to AC_SUBST both AR/ARFLAGS (thus those must have some good
530 dnl default value and automake should usually know them).
532 dnl The '][' hides this use from 'aclocal'.
533 m4_ifdef([A][M_PROG_AR], [A][M_PROG_AR], [:])
536 dnl In case the code above has not helped with setting AR/ARFLAGS, use
537 dnl Automake-documented default values for AR and ARFLAGS, but prefer
538 dnl ${host}-ar over ar (useful for cross-compiling).
539 AC_CHECK_TOOL([AR], [ar], [ar])
540 if test -z "$ARFLAGS"; then
546 if test -z "$RANLIB"; then
547 if test $gl_cv_c_amsterdam_compiler = yes; then
550 dnl Use the ranlib program if it is available.
558 # This definition is copied from post-2.69 Autoconf and overrides the
559 # AC_C_RESTRICT macro from autoconf 2.60..2.69. It can be removed
560 # once autoconf >= 2.70 can be assumed. It's painful to check version
561 # numbers, and in practice this macro is more up-to-date than Autoconf
562 # is, so override Autoconf unconditionally.
563 AC_DEFUN([AC_C_RESTRICT],
564 [AC_CACHE_CHECK([for C/C++ restrict keyword], [ac_cv_c_restrict],
566 # The order here caters to the fact that C++ does not require restrict.
567 for ac_kw in __restrict __restrict__ _Restrict restrict; do
570 [[typedef int *int_ptr;
571 int foo (int_ptr $ac_kw ip) { return ip[0]; }
572 int bar (int [$ac_kw]); /* Catch GCC bug 14050. */
573 int bar (int ip[$ac_kw]) { return ip[0]; }
578 return foo (t) + bar (t);
580 [ac_cv_c_restrict=$ac_kw])
581 test "$ac_cv_c_restrict" != no && break
584 AH_VERBATIM([restrict],
585 [/* Define to the equivalent of the C99 'restrict' keyword, or to
586 nothing if this is not supported. Do not define if restrict is
587 supported directly. */
589 /* Work around a bug in older versions of Sun C++, which did not
590 #define __restrict__ or support _Restrict or __restrict__
591 even though the corresponding Sun C compiler ended up with
592 "#define restrict _Restrict" or "#define restrict __restrict__"
593 in the previous line. This workaround can be removed once
594 we assume Oracle Developer Studio 12.5 (2016) or later. */
595 #if defined __SUNPRO_CC && !defined __RESTRICT && !defined __restrict__
597 # define __restrict__
599 case $ac_cv_c_restrict in
601 no) AC_DEFINE([restrict], []) ;;
602 *) AC_DEFINE_UNQUOTED([restrict], [$ac_cv_c_restrict]) ;;
607 # is like AC_C_BIGENDIAN, except that it can be AC_REQUIREd.
608 # Note that AC_REQUIRE([AC_C_BIGENDIAN]) does not work reliably because some
609 # macros invoke AC_C_BIGENDIAN with arguments.
610 AC_DEFUN([gl_BIGENDIAN],
615 # gl_CACHE_VAL_SILENT(cache-id, command-to-set-it)
616 # is like AC_CACHE_VAL(cache-id, command-to-set-it), except that it does not
617 # output a spurious "(cached)" mark in the midst of other configure output.
618 # This macro should be used instead of AC_CACHE_VAL when it is not surrounded
619 # by an AC_MSG_CHECKING/AC_MSG_RESULT pair.
620 AC_DEFUN([gl_CACHE_VAL_SILENT],
622 saved_as_echo_n="$as_echo_n"
624 AC_CACHE_VAL([$1], [$2])
625 as_echo_n="$saved_as_echo_n"
628 # AS_VAR_COPY was added in autoconf 2.63b
629 m4_define_default([AS_VAR_COPY],
630 [AS_LITERAL_IF([$1[]$2], [$1=$$2], [eval $1=\$$2])])