1 GNU Autoconf NEWS - User visible changes.
3 * Major changes in Autoconf 2.64 (????-??-??) [stable]
4 Released by Eric Blake, based on git versions 2.63.*.
6 ** AC_LANG_ERLANG works once again (regression introduced in 2.61a).
8 ** Autotest testsuites accept an option --jobs[=N] for parallel testing.
10 ** Autotest testsuites do not attempt to write startup error messages
11 to the log file before that is opened (regression introduced in 2.63).
13 ** Configure scripts now use shell functions.
15 ** The following documented m4sugar macros are new:
16 m4_curry m4_default_quoted m4_map_args m4_map_args_pair
19 ** The following m4sugar macros are documented now:
22 ** The following documented m4sh macros are new:
23 AS_LINENO_PREPARE AS_ME_PREPARE AS_VAR_APPEND AS_VAR_ARITH
26 ** The following m4sh macros are documented now:
27 AS_ECHO AS_ECHO_N AS_EXIT AS_LITERAL_IF AS_UNSET AS_VAR_IF
28 AS_VAR_POPDEF AS_VAR_PUSHDEF AS_VAR_SET AS_VAR_SET_IF
29 AS_VAR_TEST_SET AS_VERSION_COMPARE
31 ** The m4sh macros AS_IF and AS_CASE can now be used in shell lists.
32 The responsibility for supplying a trailing newline now belongs to
33 the call site, but since most users did not add dnl, this generally
34 results in fewer empty lines in configure.
37 * Major changes in Autoconf 2.63 (2008-09-09) [stable]
38 Released by Eric Blake, based on git versions 2.62.*.
40 ** AC_C_BIGENDIAN does not mistakenly report "universal" for some
41 bigendian hosts, a regression introduced with universal binary
44 ** AC_PATH_X now includes /lib64 and /usr/lib64 in its list of default
47 ** AC_USE_SYSTEM_EXTENSIONS no longer conflicts with an external
48 AC_DEFINE([__EXTENSIONS__]). This fixes a regression introduced in
49 2.62 when using macros such as AC_AIX that were made obsolete in
50 favor of the more portable AC_USE_SYSTEM_EXTENSIONS.
52 ** AC_CHECK_TARGET_TOOLS is usable in the non-cross-compile case.
54 ** Newly obsolete macros
55 The following macro has been marked obsolete, since current porting
56 targets can safely assume C89 semantics that signal handlers return
57 void. We have no current plans to remove the macro.
61 ** The macros m4_map and m4_map_sep now ignore any list elements
62 consisting of just empty quotes, and m4_map_sep now expands its
63 separator. This fixes a regression in 2.62 when these macros were
64 first documented, for the sake of clients expecting the semantics
65 that these macros had prior to that time. The new macros m4_mapall
66 and m4_mapall_sep, along with extra quoting of the separator, can
67 be used to get the semantics that m4_map_sep had in 2.62.
69 ** Clients of m4_expand, such as AS_HELP_STRING and AT_SETUP, can now
70 handle properly quoted but otherwise unbalanced parentheses (for
71 some macros, this fixes a regression in 2.62).
73 ** Two new quadrigraphs have been introduced: @{:@ for (, and @:}@ for ),
74 allowing the output of unbalanced parentheses in more contexts.
76 ** The following m4sugar macros are new:
77 m4_joinall m4_mapall m4_mapall_sep m4_reverse m4_set_add
78 m4_set_add_all m4_set_contains m4_set_contents m4_set_delete
79 m4_set_difference m4_set_dump m4_set_empty m4_set_foreach
80 m4_set_intersection m4_set_list m4_set_listc m4_set_remove
81 m4_set_size m4_set_union
83 ** The following m4sugar macros now accept multiple arguments, as is the
84 case with underlying m4:
85 m4_defn m4_popdef m4_undefine
87 ** The following m4sugar macros now guarantee linear scaling; they
88 previously had linear scaling with m4 1.6 but quadratic scaling
89 when using m4 1.4.x. All macros built on top of these also gain
90 the scaling improvements.
91 m4_bmatch m4_bpatsubsts m4_case m4_cond m4_do m4_dquote_elt
92 m4_foreach m4_join m4_list_cmp m4_map m4_map_sep m4_max
95 ** AT_KEYWORDS once again performs expansion on its argument, such that
96 AT_KEYWORDS([m4_if([$1], [], [default])]) no longer complains about
97 the possibly unexpanded m4_if [regression introduced in 2.62].
99 ** Config header templates `#undef UNDEFINED /* comment */' do not lead to
100 nested comments any more; regression introduced in 2.62.
103 * Major changes in Autoconf 2.62 (2008-04-05) [stable]
104 Released by Eric Blake, based on git versions 2.61a.*.
106 ** Many optimizations have been applied to make overall execution faster.
108 ** Autotest now makes use of shell functions.
110 ** config.status now uses awk instead of sed also for config headers.
112 - As a side effect, AC_DEFINE and AC_DEFINE_UNQUOTED now handle multi-line
113 values, i.e., backslash-newline combinations are handled correctly.
114 Further, for config headers, the total size of values is not limited by
115 the POSIX length limit of text lines any more, only each single line.
117 ** New config variable `top_build_prefix'.
119 ** New Autoconf macros:
120 AC_AUTOCONF_VERSION AC_OPENMP AC_PATH_PROGS_FEATURE_CHECK
122 ** AC_C_BIGENDIAN now supports universal binaries a la Mac OS X.
124 ** AC_C_RESTRICT now prefers to #define 'restrict' to a variant spelling
125 like '__restrict' if the variant spelling is available, as this is
126 more likely to work when mixing C and C++ code.
128 ** AC_CHECK_ALIGNOF's type argument T is now documented better: it must
129 be a string of tokens such that "T y;" is a valid member declaration
132 ** AC_CHECK_SIZEOF now accepts objects as well as types: the general rule
133 is that sizeof (X) works, then AC_CHECK_SIZEOF (X) should work.
135 ** AC_CHECK_TYPE and AC_CHECK_TYPES now work on any C type-name; formerly,
136 they did not work for function types. In C++, they now work on any
137 type-id that can be the operand of sizeof; this is similar to C,
138 except it excludes anonymous struct and union types. Formerly,
139 some (but not all) C++ types involving anonymous struct and union
140 were accepted, though this was not documented.
142 ** AC_CONFIG_LINKS now prefers to link against files in the build tree
143 if found, and it works to link against a file of the same name in
144 the source tree, even if both trees coincide.
146 ** AC_INIT no longer alters $@; regression introduced in 2.60.
148 ** AC_USE_SYSTEM_EXTENSIONS now defines _ALL_SOURCE for Interix platforms.
150 ** AS_HELP_STRING no longer underquotes its first argument; it also handles
151 the case where the first argument contains single-quoted commas.
152 For example, "AS_HELP_STRING([-a, [--arg[=foo]]], [bar])" produces:
153 " -a, --arg[=foo] bar"
154 Additionally, the macro now takes two additional arguments,
155 indent-column and wrap-column; these should not normally be needed,
156 but can be used to fine-tune how the output text is wrapped.
158 ** AC_PROG_INSTALL now requires an install program that can install multiple
159 files into a target directory.
161 ** The command 'autoconf -' now correctly processes a file from stdin.
163 ** 'autoreconf -m' now honors $MAKE.
165 ** For all of the directory arguments for 'configure', such as '--prefix'
166 or '--bindir', trailing slashes are stripped. As an example, if
167 tab completion in the user's shell appends trailing slashes, the
168 command './configure --prefix=/usr/' will still result in an
169 expanded libdir value of /usr/lib, not /usr//lib.
171 ** `configure --help=recursive' now works in read-only trees and from
172 unconfigured build trees.
174 ** If precious variables differ only in whitespace, then the cache consistency
175 check warns instead of fails, and reuses the old value.
177 ** AT_BANNER is now documented.
179 ** AT_SETUP now handles macro expansions properly when calculating line
182 ** Autotest now determines $srcdir correctly.
184 ** Testsuites built by autotest now accept a -C/--directory=DIR option
185 to adjust the working directory prior to creating files.
187 ** Autoconf now requires GNU M4 1.4.5 or later. Earlier versions of M4 have
188 a bug in macro tracing that interferes with the interaction between
189 Autoconf and Automake. GNU M4 1.4.11 or later is recommended. The
190 configure search for a working M4 is improved.
192 ** For portability with the eventual M4 2.0, macros should no longer use
193 anything larger than $9 to refer to arguments.
195 ** Documentation for m4sugar is improved.
197 - The following macros were previously available as undocumented
198 interfaces; the macros are now documented as stable interfaces.
200 __oline__ m4_assert m4_bmatch m4_bpatsubsts m4_car m4_case
201 m4_cdr m4_default m4_divert_once m4_divert_pop m4_divert_push
202 m4_divert_text m4_do m4_errprintn m4_fatal m4_flatten
203 m4_ifndef m4_ifset m4_ifval m4_ifvaln m4_location
204 m4_n m4_shiftn m4_strip m4_warn
206 - The following macros were previously available as undocumented
207 interfaces, but had bug fixes or semantic changes as part of this
208 release. Packages that relied on the undocumented behavior
209 should be analyzed to make sure they will still work with the
210 new documented behavior.
212 m4_cmp m4_list_cmp m4_join m4_map m4_map_sep m4_sign
213 m4_text_box m4_text_wrap m4_version_compare
215 - The m4_wrap macro used to have unspecified order, but now
216 guarantees FIFO order. m4_wrap_lifo was added to guarantee LIFO
219 - Packages using the undocumented m4sugar macro m4_PACKAGE_VERSION
220 should consider using the new AC_AUTOCONF_VERSION instead.
222 - m4sugar macros that are not documented in the manual are still
223 deemed experimental, and should not be used outside of Autoconf.
225 ** The m4sugar macros m4_append and m4_append_uniq, first documented in
226 2.60, have been fixed to treat both the string and the separator
227 arguments consistently with regards to quoting. Prior to this fix,
228 m4_append_uniq could mistakenly duplicate entries if the expansion
229 of the separator resulted in a different string (for example, if it
230 contained quotes, a comma, or a macro name). However, it means
231 that programs previously using
232 m4_append([name], [string], [[, ]])
233 are now using a four-character separator instead of the intended
234 comma and space. If you need portability to earlier versions of
235 Autoconf, you can insert the following snippet after AC_INIT but
236 before any other macro expansions, to enforce the new semantics:
237 m4_pushdef([m4_append], [m4_define([$1],
238 m4_ifdef([$1], [m4_defn([$1])[$3]])[$2])])
239 Additionally, m4_append_uniq now takes optional parameters that can
240 be used to take action depending on whether anything was appended,
241 and warns if a non-empty separator occurs within the string being
242 appended, since that can lead to duplicates.
244 ** The following m4sugar macros are new:
245 m4_append_uniq_w m4_apply m4_combine m4_cond m4_count
246 m4_dquote_elt m4_echo m4_expand m4_ignore m4_make_list m4_max
247 m4_min m4_newline m4_shift2 m4_shift3 m4_unquote m4_wrap_lifo
249 ** Warnings are now generated by default when an installer invokes
250 'configure' with an unknown --enable-* or --with-* option.
251 These warnings can be disabled with the new AC_DISABLE_OPTION_CHECKING
252 macro, or by invoking 'configure' with --disable-option-checking.
254 ** Existing obsolete macros
255 The documentation for the following macros is adjusted to make it
256 more clear that they have previously been marked obsolete, as their
257 functionality can be accomplished by other macros. We have no
258 current plans to remove them from Autoconf.
260 AC_ENABLE AC_STRUCT_ST_BLKSIZE AC_STRUCT_ST_RDEV AC_WITH
262 ** Newly obsolete macros
263 The following macros have been marked obsolete, as they only
264 perform a subset of AC_USE_SYSTEM_EXTENSIONS. We have no current
265 plans to remove them.
267 AC_AIX AC_GNU_SOURCE AC_ISC_POSIX AC_MINIX
269 ** AC_C_LONG_DOUBLE is obsolescent.
270 The documentation now says that AC_C_LONG_DOUBLE is obsolescent: it
271 tests for problems that are so old that it is no longer of
272 practical importance on current systems. New programs need not use
273 AC_C_LONG_DOUBLE. We have no current plans to remove it.
275 ** AC_DIAGNOSE, AC_WARNING, and AC_FATAL are obsolescent.
276 The documentation now favors the use of M4sugar macros m4_warn and
277 m4_fatal, since the naming makes it more obvious that the
278 diagnostics are associated with M4 expansion (ie. when running
279 `autoconf'), and offers less confusion with the AC_MSG_ERROR,
280 AC_MSG_FAILURE, and AC_MSG_WARN macros which manage diagnostics
281 when running `configure'. We have no current plans to remove these
285 * Major changes in Autoconf 2.61a (2006-12-11)
287 ** AC_FUNC_FSEEKO was broken in 2.61; it didn't make fseeko and ftello visible
288 on many platforms. This has been fixed.
290 ** AC_FUNC_SETVBUF_REVERSED is now obsolete. It is still defined for backward
291 compatibility but it does nothing. The macro was already
292 obsolescent, as the last systems to have the problem were those
293 based on SVR2, which became obsolete in 1987. The macro had bugs
294 on some modern systems and could no longer be maintained reliably
295 due to lack of ancient systems to test it on.
297 ** config.status now uses awk instead of sed for most substitutions, for speed.
299 - As a side effect multi-line values of substituted variables no
300 longer have a small limit in total size, though for portability
301 each line should not exceed the POSIX length limit for text lines.
303 - It is now documented that Makefile.in should not contain
304 overlapping variable occurrences, e.g., @VAR1@VAR2@.
305 Autoconf's behavior was always iffy in such cases, and the
306 awk implementation has changed the behavior.
308 ** Many uses of 'echo' have been rewritten so that Autoconf-generated
309 scripts have fewer problems with strings or file names containing
310 embedded special characters such as backslash or leading "-". This
311 was implemented by using `printf '%s\n' "$foo"' instead of `echo
312 "$foo"' when printf works. Due to the implementation technique
313 used, Autoconf-generated scripts now run considerably more slowly
314 on ancient implementations lacking printf. However, this should
315 not be a problem, since Autoconf-generated scripts in practice
316 invariably find a more-modern shell these days.
319 * Major changes in Autoconf 2.61 (2006-11-17)
321 ** New macros AC_C_FLEXIBLE_ARRAY_MEMBER, AC_C_VARARRAYS.
323 ** AC_ARG_ENABLE and AC_ARG_WITH now allow '.' in feature and package names.
326 * Major changes in Autoconf 2.60b (2006-10-22)
329 Autoconf-generated shell scripts no longer export BIN_SH, due to
330 configuration hassles with this. Installers who need BIN_SH in
331 their environment should set it before invoking 'configure' and
332 'make'. As far as we know, this affects only Unixware installations.
334 ** Obsolescent macros
335 The documentation now says that the following macros are obsolescent,
336 as they are superseded by Gnulib:
338 AC_FUNC_FNMATCH AC_FUNC_FNMATCH_GNU AC_FUNC_GETLOADVG AC_REPLACE_FNMATCH
340 New programs should use the Gnulib counterparts of these macros.
341 We have no current plans to remove them from Autoconf.
343 ** AC_COMPUTE_INT no longer caches or reports results.
345 ** AC_CHECK_DECL now also works with aggregate objects.
347 ** AC_USE_SYSTEM_EXTENSIONS now defines _TANDEM_SOURCE for NonStop platforms.
349 ** GNU M4 1.4.7 or later is now recommended.
352 New M4sugar macro, which is more secure than the POSIX M4 maketemp.
355 Now an alias for m4_mkstemp.
357 * Major changes in Autoconf 2.60a (2006-08-25)
359 ** GNU M4 1.4.6 or later is now recommended.
361 ** The check for C99 now tests for varargs macros, as documented.
362 It also tests that the preprocessor supports 64-bit integers.
364 ** Autoconf now uses constructs like "#ifdef HAVE_STDLIB_H" rather than
365 "#if HAVE_STDLIB_H", so that it now works with "gcc -Wundef -Werror".
367 ** The functionality of the undocumented _AC_COMPUTE_INT is now provided
368 by a public and documented macro, AC_COMPUTE_INT. The parameters to the
369 two macros are different, so autoupdate will not change the old private name
370 to the new one. _AC_COMPUTE_INT may be removed in a future release.
372 ** AC_TYPE_LONG_LONG_INT and AC_TYPE_UNSIGNED_LONG_LONG_INT now require
373 that long long types be at least 64 bits wide, as C99 and tradition
374 requires. Formerly, they accepted implementations of any width.
377 * Major changes in Autoconf 2.60
379 Released 2006-06-23, by Ralf Wildenhues.
381 ** Autoconf no longer depends on whether m4wrap is FIFO (as Posix requires)
382 or LIFO (as in GNU M4 1.4.x). GNU M4 2.0 is expected to conform to Posix
383 here, so m4wrap/m4_wrap users should no longer depend on LIFO behavior.
385 ** Provide a way to turn off warnings about the changed directory variables.
387 * Major changes in Autoconf 2.59d
389 Released 2006-06-05, by Ralf Wildenhues.
391 ** GNU make now recommended for VPATH builds
392 INSTALL now suggests VPATH builds (e.g., "sh ../srcdir/configure")
393 only if you use GNU make. In practice, other 'make' implementations
394 have too many subtle incompatibilities in their support for VPATH.
395 Many packages (including Autoconf itself) are portable to other
396 'make' implementations, but some packages are not, and recommending
397 GNU make keeps the installation instructions simpler.
399 ** Even more safety checks for the new Directory variables:
400 Warn about suspicious `${datarootdir}' found in config files output.
402 ** AC_TRY_COMMAND, AC_TRY_EVAL, ac_config_guess, ac_config_sub, ac_configure
403 These never-documented macros and variables have been marked with
404 comments saying that they may be removed in a future release,
405 because their use can lead to unintended code being executed.
406 If you need functionality that only these macros or variables
407 currently supply, please write bug-autoconf@gnu.org.
409 ** AC_SUBST, AC_DEFINE
410 Literal arguments to these are passed to m4_pattern_allow now.
413 Passing 'ac_cv_prog_cc_stdc=no' to 'configure' now sets ac_cv_prog_cc_c99
414 and ac_cv_prog_cc_c89 to 'no' as well, for backward compatibility with
415 obsolete K&R tests in the Automake test suite.
424 Now more robust with special characters in file names, or when
425 multiple processes create the same directory at the same time.
427 ** Obsolescent macros
428 The documentation now says that the following macros are obsolescent:
429 they test for problems that are so old that they are no longer of
430 practical importance on current systems.
432 AC_C_BACKSLASH_A AC_FUNC_MEMCMP AC_HEADER_DIRENT
433 AC_C_CONST AC_FUNC_SELECT_ARGTYPES AC_HEADER_STAT
434 AC_C_PROTOTYPES AC_FUNC_SETPGRP AC_HEADER_STDC
435 AC_C_STRINGIZE AC_FUNC_SETVBUF_REVERSED AC_HEADER_SYS_WAIT
436 AC_C_VOLATILE AC_FUNC_STAT AC_HEADER_TIME
437 AC_FUNC_CLOSEDIR_VOID AC_FUNC_STRFTIME AC_ISC_POSIX
438 AC_FUNC_GETPGRP AC_FUNC_UTIME_NULL AC_PROG_GCC_TRADITIONAL
439 AC_FUNC_LSTAT AC_FUNC_VPRINTF AC_STRUCT_TM
441 New programs need not use these macros. We have no current plans to
445 For compatibility with future Libtool 2.0, autoreconf will invoke
446 libtoolize with the option `--ltdl' now, if LT_CONFIG_LTDL_DIR is
449 * Major changes in Autoconf 2.59c
451 Released 2006-04-12, by Ralf Wildenhues.
453 ** The configure command now redirects standard input from /dev/null,
454 to help avoid problems with subsidiary commands that might mistakenly
455 read standard input. AS_ORIGINAL_STDIN_FD points to the original
456 standard input before this redirection, if you really want configure to
457 read from standard input.
459 ** Directory variables adjusted to recent changes in the GNU Coding Standards.
460 The following directory variables are new:
462 datarootdir read-only architecture-independent data root [PREFIX/share]
463 localedir locale-specific message catalogs [DATAROOTDIR/locale]
464 docdir documentation root [DATAROOTDIR/doc/PACKAGE]
465 htmldir html documentation [DOCDIR]
466 dvidir dvi documentation [DOCDIR]
467 pdfdir pdf documentation [DOCDIR]
468 psdir ps documentation [DOCDIR]
470 The following variables have new default values:
472 datadir read-only architecture-independent data [DATAROOTDIR]
473 infodir info documentation [DATAROOTDIR/info]
474 mandir man documentation [DATAROOTDIR/man]
476 This means that if you use any of `@datadir@', `@infodir@', or
477 `@mandir@' in a file, you will have to ensure `${datarootdir}' is
478 defined in this file. As a temporary measure, if any of those are
479 found but no mention of `datarootdir', the substitutions will be
480 replaced with values that do not contain `${datarootdir}', and a
481 warning will be issued.
483 ** @top_builddir@ is now a dir name: it is always nonempty and doesn't have
484 a trailing slash. Similar change will be made to ac_top_builddir in a
485 future release; the old style value, which matches (../)*, is (and will
486 continue to be) available as ac_top_build_prefix.
489 New macro to check for support of 'typeof' syntax a la GNU C.
491 ** AC_CHECK_DECLS_ONCE, AC_CHECK_FUNCS_ONCE, AC_CHECK_HEADERS_ONCE
492 New "once-only" variants of commonly-used macros, to make 'configure'
493 smaller and faster in common cases.
496 New macro to check for strtold with C99 semantics.
499 New macro that lets builder disable assertions at 'configure'-time.
502 Now checks for X11/Xlib.h and XrmInitialize (X proper) rather than
503 X11/Intrinsic.h and XtMalloc (Xt).
505 ** AC_PRESERVE_HELP_ORDER
506 New macro that causes `configure' to display help strings for AC_ARG_ENABLE
507 and AC_ARG_WITH arguments in one region, in the order defined. The default
508 behavior is to group options of each classes separately.
510 ** AC_PROG_CC, AC_PROG_CXX
511 No longer automatically arrange to declare the 'exit' function of C,
512 when a C++ compiler is used. Standard Autoconf macros no longer use
513 'exit', so this is no longer an issue for them. If you use C++, and
514 want to call 'exit', you'll have to arrange for its declaration
515 yourself. But we now suggest you return from 'main' instead.
517 ** AC_PROG_CC_C89, AC_PROG_CC_C99
518 New macros for ISO C99 support. AC_PROG_CC_C89 and AC_PROG_CC_C99
519 check for ANSI C89 and ISO C99 support respectively.
522 Has been unobsoleted, and will check if the compiler supports ISO
523 C99, falling back to ANSI C89 if not. ac_cv_prog_cc_stdc is
524 retained for backwards compatibility, assuming the value of
525 ac_cv_prog_cc_c99 or ac_cv_prog_cc_c89 (whichever is valid, in
528 ** AC_STRUCT_DIRENT_D_INO, AC_STRUCT_DIRENT_D_TYPE
529 New macros for checking commonly-used members of struct dirent.
532 The substituted value can now contain newlines.
535 The substitution now occurs only when @variable@ is on a line by itself,
536 optionally surrounded by spaces and tabs. The whole line is replaced.
538 ** AC_TYPE_LONG_DOUBLE, AC_TYPE_LONG_DOUBLE_WIDER
539 New macros to check for long double, and whether it is wider than double.
540 The old macro AC_C_TYPE_LONG_DOUBLE has been marked as obsolete;
541 applications should switch to the new macro.
543 ** AC_TYPE_INT8_T, AC_TYPE_INT16_T, AC_TYPE_INT32_T, AC_TYPE_INT64_T,
544 AC_TYPE_INTMAX_T, AC_TYPE_INTPTR_T, AC_TYPE_LONG_LONG_INT, AC_TYPE_SSIZE_T,
545 AC_TYPE_UINT8_T, AC_TYPE_UINT16_T, AC_TYPE_UINT32_T, AC_TYPE_UINT64_T,
546 AC_TYPE_UINTMAX_T, AC_TYPE_UINTPTR_T, AC_TYPE_UNSIGNED_LONG_LONG_INT
547 New macros to check for C99 and POSIX types.
549 ** AC_USE_SYSTEM_EXTENSIONS
550 New macro to enable extensions to Posix.
553 New macro which is defined to the name of the first declared config header
554 or undefined if no config headers have been declared yet.
557 The macro correctly handles quadrigraphs now.
559 ** AS_BOURNE_COMPATIBLE, AS_SHELL_SANITIZE, AS_CASE
560 These macros are new or published now.
563 New macro for copyright notices in testsuite files.
565 ** ALLOCA, LIBOBJS, LTLIBOBJS
566 Object names added to these variables are now prefixed with `${LIBOBJDIR}',
567 as in `${LIBOBJDIR}alloca.o'. LIBOBJDIR is meant to be defined from
568 `Makefile.in' in case the object files lie in a different directory.
569 The LIBOBJDIR feature is experimental.
572 Supports --no-recursive now.
574 ** New macros to support Erlang/OTP.
575 New macros for configuring paths to Erlang tools and libraries:
576 AC_ERLANG_PATH_ERLC, AC_ERLANG_NEED_ERLC, AC_ERLANG_PATH_ERL,
577 AC_ERLANG_NEED_ERL, AC_ERLANG_CHECK_LIB, AC_ERLANG_SUBST_ROOT_DIR,
578 AC_ERLANG_SUBST_LIB_DIR.
580 New macros for configuring installation of Erlang libraries:
581 AC_ERLANG_SUBST_INSTALL_LIB_DIR, AC_ERLANG_SUBST_INSTALL_LIB_SUBDIR.
583 ** The manual now mentions Gnulib more prominently.
585 ** New macros to support Objective C.
586 AC_PROG_OBJC, AC_PROG_OBJCPP.
588 * Major changes in Autoconf 2.59b
590 Released 2004-08-20, by Paul Eggert.
593 New macro that computes the default alignment of a type.
595 ** AC_CHECK_TOOL, AC_PATH_TOOL, AC_CHECK_TOOLS
596 When cross-compiling, these macros will give a warning if the tool
597 is not prefixed. In the future, unprefixed cross tools will not
598 be detected; please consult the info documentation for information
599 about the reason of this change.
601 ** AC_CHECK_TARGET_TOOL, AC_PATH_TARGET_TOOL, AC_CHECK_TARGET_TOOLS
602 New macros that detect programs whose name is prefixed with the
603 target type, if the build type and target type are different.
605 ** AC_REQUIRE_AUX_FILE
606 New trace macro that declares expected auxiliary files.
609 New macro that tests for a grep program that accepts as a long a line
612 ** AC_PROG_EGREP, AC_PROG_FGREP
613 These macros now require AC_PROG_GREP, and try EGREP="$GREP -E" and
614 FGREP="$GREP -F" respectively if possible, or else run a path search for
615 a program that accepts as long a line as possible.
618 New macro that tests for a sed program that truncates as few characters
621 * Major changes in Autoconf 2.59
623 Released 2003-11-04, by Akim Demaille
625 ** ac_abs_builddir etc.
626 Absolute file names were actually relative in 2.58.
628 * Major changes in Autoconf 2.58
630 Released 2003-11-04, by Akim Demaille
633 core.* files are no longer removed, as they may be valid user files.
635 ** autoreconf and auxiliary directory
636 Autoreconf creates the auxiliary directory if needed. This is
637 especially useful for initial "bootstrapping" of fresh CVS checkouts.
639 ** AC_CONFIG_MACRO_DIR
640 Use this macro to declare the directory for local M4 macros for aclocal.
643 No longer includes twice the same file in LIBOBJS if invoked
646 ** AC_CONFIG_COMMANDS
647 The directory for its first argument is automatically created. For
650 AC_CONFIG_COMMANDS([src/modules.hh], [...])
652 $top_builddir/src/ is created if needed.
654 ** Autotest and local.at
655 The optional file local.at is always included in Autotest test suites.
658 The warnings are always issued, including with cached runs.
659 This became a significant problem since aclocal and automake can
660 run autoconf behind the scene.
662 ** autoheader warnings
663 The warnings of autoheader can be turned off, using --warning.
664 For instance, -Wno-obsolete disables the complaints about acconfig.h
665 and other deprecated constructs.
668 AC_C_RESTRICT, AC_INCLUDES_DEFAULT, AC_LANG_ASSERT, AC_LANG_WERROR,
671 ** AC_DECL_SYS_SIGLIST
675 Now checks that mktime is the inverse of localtime.
677 ** Improve DJGPP portability
678 The Autoconf tools and configure behave better under DJGPP.
680 ** Present But Cannot Be Compiled
681 New FAQ section dedicated to the mystic
683 configure: WARNING: pi.h: present but cannot be compiled
684 configure: WARNING: pi.h: check for missing prerequisite headers?
685 configure: WARNING: pi.h: proceeding with the preprocessor's result
688 ** Concurrent executions of autom4te
689 autom4te now locks its internal files, which enables concurrent
690 executions of autom4te, likely to happen if automake, autoconf,
691 autoheader etc. are run simultaneously.
694 Use of Libtool 1.5 and higher is encouraged. Compatibility with
695 Libtool pre-1.4 is not checked.
698 Testsuites no longer rerun failed tests in verbose mode; instead,
699 failures are logged while the test is run.
701 In addition, expected failures can be marked as such.
703 * Major changes in Autoconf 2.57
705 Released 2002-12-03 by Paul Eggert.
707 Bug fixes for problems with AIX linker, with freestanding C compilers,
708 with GNU M4 limitations, and with obsolete copies of GNU documents.
710 The Free Documentation License has been upgraded from 1.1 to 1.2.
712 * Major changes in Autoconf 2.56
714 Released 2002-11-15 by Akim Demaille.
716 One packaging problem fixed (config/install-sh was not executable).
718 * Major changes in Autoconf 2.55
720 Released 2002-11-14 by Akim Demaille.
724 Have your configure.ac checked by autoscan ("autoscan").
725 Try the warning options ("autoreconf -fv -Wall").
729 - AC_CHECK_HEADER, AC_CHECK_HEADERS
730 More information on proper use.
732 - Writing Test Programs
734 This sections explains how to write good test sources to use with
735 AC_COMPILE_IFELSE etc. It documents AC_LANG_PROGRAM and so forth.
737 - AC_FOO_IFELSE vs. AC_TRY_FOO
739 Explains why Autoconf moves from AC_TRY_COMPILE etc. to
740 AC_COMPILE_IFELSE and AC_LANG_PROGRAM etc.
744 - Is more robust to different Gettext installations.
746 - Produces messages (when --verbose) to be understood by Emacs'
749 - Supports -W/--warnings.
752 Once the GNU Build System reinstalled, run `./config.status
753 --recheck && ./config.status && make' if possible.
757 - Supports --cache, and --no-cache.
759 - ~/.autom4te.cfg makes it possible to disable the caching mechanism
760 (autom4te.cache). See `Customizing autom4te' in the documentation.
767 Support for the obsoleted options -m, --macrodir, -l, --localdir is
768 dropped in favor of the safer --include/--prepend-include scheme.
773 AC_COMPILER_IFELSE, AC_FUNC_MBRTOWC, AC_HEADER_STDBOOL,
774 AC_LANG_CONFTEST, AC_LANG_SOURCE, AC_LANG_PROGRAM, AC_LANG_CALL,
775 AC_LANG_FUNC_TRY_LINK, AC_MSG_FAILURE, AC_PREPROC_IFELSE.
778 Obsoleted macros are kept for Autoconf backward compatibility, but
779 should be avoided in configure.ac. Running autoupdate is advised.
782 - AC_DEFINE/AC_DEFINE_UNQUOTED
784 We have to stop using the old compatibility scheme --that tried to
785 avoid useless backslashes-- because Libtool 1.4.3 contains a
787 AC_DEFINE([error_t], [int],
788 [Define to a type to use for \`error_t' if it is not
789 otherwise available.])
791 We have to quote the single quotes and backslashes with \. The old
792 compatibility scheme saw that ` was backslashed, and therefore did
793 not quote the single quote... Failure. Hence, Autoconf 2.54 is not
794 compatible with Libtool. Autoconf 2.55 is, but in some cases might
795 produce more \ than wanted.
797 Please, note that in the future the same problem will happen with
798 AC_MSG_*: use `autoreconf -f -Wall'.
802 - Portability of the Autoconf package to Solaris.
804 - Spurious warnings caused by config.status.
805 This bug is benign, but painful: on some systems (typically
806 FreeBSD), warnings such as:
808 config.status: creating Makefile
809 mv: Makefile: set owner/group (was: 1357/0): Operation not permitted
811 could be issued. This is fixed.
814 Simultaneous executions of config.status are possible again.
816 - Precious variables accumulation
818 config.status could stack several copies of the precious variables
822 ** Plans for later versions
826 The compatibility hooks with the old scheme will be completely
827 removed. Please, advice/use `--build', `--host', and `--target'
830 - AC_CHECK_HEADER, AC_CHECK_HEADERS
832 The tests will be stricter, please make sure your invocations are
837 Shell functions will gradually be introduced, probably starting with
838 Autotest. If you know machines which are in use that you suspect
839 *not* to support shell functions, please run the test suite of
840 Autoconf 2.55 on it, and report the results to
841 bug-autoconf@gnu.org.
845 Special characters in AC_MSG_* need not be quoted. Currently,
846 Autoconf has heuristics to decide when a string is escaped, or has
847 to be escaped. This scheme is fragile, and will be removed; the
848 only risk is uglified messages. Please, run `autoreconf -f -Wall'
849 to find occurrences that will be affected.
851 * Major changes in Autoconf 2.54
853 Released 2002-09-13 by Akim Demaille.
857 - autoreconf no longer changes the version of the gettext/po/intl
858 support files. It now adds the files the correspond to the
859 AM_GNU_GETTEXT_VERSION declared in configure.ac.
861 Warning: It now relies on the 'autopoint' program, which is part
862 of GNU gettext 0.11.4 and newer.
864 Please note that you need to have a GNU gettext version that
865 corresponds at least to the AM_GNU_GETTEXT_VERSION declared
866 in configure.ac. You can upgrade to newer GNU gettext versions,
867 though, without needing to change configure.ac.
869 - The -I DIR or --include=DIR option now appends DIR to the include path
870 instead of prepending; this is for consistency with other GNU tools.
871 The new -B DIR or --prepend-include=DIR option has the old behavior.
876 Now handles all the gory details about LIBOBJS and LTLIBOBJS.
877 Please, remove lines such as
879 # This is necessary so that .o files in LIBOBJS are also
880 # built via the ANSI2KNR-filtering rules.
881 LIBOBJS=`echo $LIBOBJS|sed 's/\.o /\$U.o /g;s/\.o$/\$U.o/'`
883 and read the `AC_LIBOBJ vs LIBOBJS' section. Do not define U in
884 your Makefiles either.
886 - AC_CONFIG_LINKS now makes copies if it can't make links.
888 - AC_FUNC_FNMATCH now tests only for POSIX compatibility, reverting to
889 Autoconf 2.13 behavior. The new macro AC_FUNC_FNMATCH_GNU also
890 tests for GNU extensions to fnmatch, and replaces fnmatch if needed.
892 - AC_FUNC_SETVBUF_REVERSED no longer fails when cross-compiling.
894 - AC_PROG_CC_STDC is integrated into AC_PROG_CC.
896 - AC_PROG_F77 default search no longer includes cf77 and cfg77.
900 AC_C_BACKSLASH_A, AC_CONFIG_LIBOBJ_DIR, AC_GNU_SOURCE,
901 AC_PROG_EGREP, AC_PROG_FGREP, AC_REPLACE_FNMATCH,
902 AC_FUNC_FNMATCH_GNU, AC_FUNC_REALLOC, AC_TYPE_MBSTATE_T.
905 looks for getloadavg.c in the CONFIG_LIBOBJ_DIR.
908 Now defines HAVE_MALLOC to 0 if `malloc' does not work, and asks
909 for an AC_LIBOBJ replacement.
913 - Spurious complaints from `m4_bmatch' about invalid regular
914 expressions are suppressed.
916 - Empty top_builddirs are properly handled.
918 - AC_CHECK_MEMBER works correctly when the member is an aggregate.
921 Now colon in the optional path arguments are properly handled.
923 ** Improved portability
925 - Both Autoconf the package, and the scripts it produces, should run
926 more reliably with Zsh. Bear in mind it is the default Bourne shell
929 - Autoconf and the scripts it produces no longer assume the existence of
930 the obsolescent commands egrep and fgrep.
934 - Limitations of Make
938 The GNATS base moved to
939 http://bugs.gnu.org/cgi-bin/gnatsweb.pl?database=autoconf
940 (It is no longer available, though.)
945 Now contains the list of ouput variables and files (AC_SUBST,
948 * Major changes in Autoconf 2.53
950 Released 2002-03-08 by Akim Demaille.
954 Perl 5.005_03 or later is required: autom4te is written in Perl and is
955 needed by autoconf. autoheader, autoreconf, ifnames, and autoscan are
961 Argument requirements, output variables, defined macros.
962 - M4sugar, M4sh, Autotest
964 - Double quoting macros
965 AC_TRY_CPP, AC_TRY_COMPILE, AC_TRY_LINK and AC_TRY_RUN.
967 The Autoconf manual is now distributed under the terms of the GNU FDL.
968 - Section `Hosts and Cross-Compilation'
969 Explains the rationale for the 2.5x changes in the cross-compilation
970 chain, and in the relationships between build, host, and target
972 Emphasizes that `cross-compilation' == `--host is given'.
973 If you are working on compilers etc., be sure to read this section.
974 - Section `AC_LIBOBJ vs. LIBOBJS'
975 Explains why assigning LIBOBJS directly is now an error.
976 Details how to update the code.
981 Now used instead of hard coded line numbers.
982 This eases the comparison of `configure's, and diminishes the
983 pressure over control version archives.
984 Automatic replacement for shells that don't support this feature.
985 - New output variables
986 @builddir@, @top_builddir@, @abs_srcdir@, @abs_top_srcdir@, @abs_builddir@,
991 Autoconf and Autotest modes are provided.
996 New, used by the Autoconf suite to cache and speed up most processing.
998 Supported by autom4te, autoconf and autoheader.
1000 Replaces --autoconf-dir and --localdir in autoconf, autoheader,
1001 autoupdate, and autoreconf.
1003 No longer passes --cygnus, --foreign, --gnits, --gnu, --include-deps:
1004 automake options are to be given via AUTOMAKE_OPTIONS.
1006 Runs gettextize and libtoolize when appropriate.
1008 --m4dir is no longer supported.
1010 Now runs only in the specified directories, defaulting to `.',
1011 but understands AC_CONFIG_SUBDIRS for dependent directories.
1012 Before, it used to run on all the `configure.ac' found in the
1014 Independent packages are properly updated.
1018 - The top level $prefix is propagated to the AC_CONFIG_SUBDIRS configures.
1020 Under the user pressure, $? is finally available. Probably a mistake.
1021 - AC_F77_LIBRARY_LDFLAGS now supports the HP/UX f90 compiler.
1022 - Precious variables accumulation
1023 config.status could stack several copies of the precious variables
1025 - AC_PATH_PROG and family.
1026 Works properly when given a literal path.
1028 Somewhere since 2.13, the result had been reversed.
1032 - AC_C_BIGENDIAN supports the cross-compiling case.
1033 - AC_C_BIGENDIAN accepts ACTION-IF-TRUE, ACTION-IF-FALSE, and
1034 ACTION-IF-UNKNOWN arguments. All are facultative, and the default
1035 for ACTION-IF-TRUE is to define WORDS_BIGENDIAN like AC_C_BIGENDIAN
1037 - AC_C_LONG_DOUBLE now succeeds only if `long double' has more range or
1038 precision than `double'.
1043 It now defines the preprocessor symbols PACKAGE_NAME,
1044 PACKAGE_TARNAME, PACKAGE_VERSION, PACKAGE_STRING, and
1048 Admits a fourth optional parameter: the tar name.
1050 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS.
1051 Provide the user with srcdir, ac_srcdir, ac_top_srcdir, ac_builddir,
1052 ac_top_builddir, ac_abs_srcdir, ac_abs_top_srcdir, ac_abs_builddir,
1053 ac_abs_top_builddir.
1055 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS and AC_OUTPUT.
1056 Are much less expensive when using long lists of files.
1059 Works with shell variables, and non alphanumeric names.
1063 - AC_FUNC_STRERROR_R now sets STRERROR_R_CHAR_P, not HAVE_WORKING_STRERROR_R,
1064 because POSIX 1003.1-200x draft 7 says strerror_r returns int, not char *.
1066 - AC_FUNC_STRTOD substitutes POW_LIB.
1071 * Major changes in Autoconf 2.52
1073 Released 2001-07-18 by Akim Demaille.
1078 This feature was present in autoconf 2.50 but was not documented.
1079 For example, `@<:@' is translated to `[' just before output. This
1080 is useful when writing strings that contain unbalanced quotes, or
1081 other hard-to-quote constructs.
1082 - m4_pattern_forbid, m4_pattern_allow
1083 - Tips for upgrading from 2.13.
1084 - Using autoscan to maintain a configure.ac.
1087 - Now include stdint.h.
1088 - sys/types.h and sys/stat.h are guarded.
1089 - strings.h is included if available, and not conflicting with string.h.
1092 - The test suite is more robust and presents less false failures.
1093 - Invocation of GNU M4 now robust to POSIXLY_CORRECT.
1094 - configure accepts --prefix='' again.
1095 - AC_CHECK_LIB works properly when its first argument is not a
1097 - HAVE_INTTYPES_H is defined only if not conflicting with sys/types.h.
1098 - build_, host_, and target_alias are AC_SUBST as in 2.13.
1099 - AC_ARG_VAR properly propagates precious variables inherited from the
1100 environment to ./config.status.
1101 - Using --program-suffix/--program-prefix is portable.
1102 - Failures to detect the default compiler's output extension are less
1104 - `config.status foo' works properly when `foo' depends on variables
1105 set in an AC_CONFIG_THING INIT-CMD.
1106 - autoheader is more robust to broken input.
1107 - Fixed Fortran name-mangling and link tests on a number of systems,
1108 e.g. NetBSD; see AC_F77_DUMMY_MAIN, below.
1111 - AC_CHECK_HEADER and AC_CHECK_HEADERS support a fourth argument to
1112 specify pre-includes. In this case, the headers are compiled with
1113 cc, not merely preprocessed by cpp. Therefore it is the _usability_
1114 of a header which is checked for, not just its availability.
1115 - AC_ARG_VAR refuses to run configure when precious variables have
1117 - Versions of compilers are dumped in the logs.
1118 - AC_CHECK_TYPE recognizes use of `foo_t' as a replacement type.
1121 - AC_PATH_XTRA only adds -ldnet to $LIBS if it's needed to link.
1122 - AC_FUNC_WAIT3 and AC_SYS_RESTARTABLE_SYSCALLS are obsoleted.
1123 - AM_FUNC_ERROR_AT_LINE, AM_FUNC_FNMATCH, AM_FUNC_MKTIME,
1124 AM_FUNC_OBSTACK, and AM_FUNC_STRTOD are now activated.
1125 Be sure to read `Upgrading from Version 2.13' to understand why
1126 running `autoupdate' is needed.
1127 - AC_F77_DUMMY_MAIN, AC_F77_MAIN: new macros to detect whether
1128 a main-like routine is required/possible when linking C/C++ with
1129 Fortran. Users of e.g. AC_F77_WRAPPERS should be aware of these.
1130 - AC_FUNC_GETPGRG behaves better when cross-compiling.
1132 * Major changes in Autoconf 2.51
1133 There was no release of Autoconf 2.51 since some packagers had used
1134 this version number without permission to ship intermediary versions
1135 of 2.50. The version was skipped to avoid confusion.
1137 * Major changes in Autoconf 2.50
1139 Released 2001-05-21 by Akim Demaille.
1141 ** Lots of bug fixes
1142 There have been far too many to enumerate them here. Check out
1143 ChangeLog if you really want to know more.
1145 ** Improved documentation
1146 In particular, portability issues are better covered.
1149 All the standard GNU Makefile targets are supported. The layout has
1150 changed: m4/ holds the M4 extensions Autoconf needs for its
1151 configuration, doc/ contains the documentation, and tests/ contains
1154 ** Man pages are provided
1155 For autoconf, autoreconf, autoupdate, autoheader, autoscan, ifnames,
1156 config.guess, config.sub.
1160 Provides a safe and powerful means to trace the macro uses. This
1161 provide the parsing layer for tools which need to `study'
1165 Specify what category of warnings should be enabled.
1167 - When recursing into subdirectories, try for configure.gnu before
1168 configure to adapt for packages not using autoconf on case-insensitive
1172 More errors are now caught (circular AC_REQUIRE dependencies,
1173 AC_DEFINE in the action part of an AC_CACHE_CHECK, too many pops
1174 etc.). In addition, their location and call stack are given.
1177 autoupdate is much more powerful, and is able to provide the glue code
1178 which might be needed to move from an old macro to its newer
1181 You are strongly encouraged to use it to modernize both your
1182 `configure.in' and your .m4 extension files.
1185 The internal machinery of autoheader has completely changed. As a
1186 result, using `acconfig.h' should be considered to be obsoleted, and
1187 you are encouraged to get rid of it using the AH macros.
1192 ** Fortran 77 compilers
1193 Globally, the support for Fortran 77 is considerably improved.
1195 Support for automatically determining a Fortran 77 compiler's
1196 name-mangling scheme. New CPP macros F77_FUNC and F77_FUNC_ are
1197 provided to wrap C/C++ identifiers, thus making it easier and more
1198 transparent for C/C++ to call Fortran 77 routines, and Fortran 77 to
1199 call C/C++ routines. See the Texinfo documentation for details.
1202 The test suite no longer uses DejaGNU. It should be easy to submit
1203 test cases in this new framework.
1206 - --help, --help=long, -hl
1207 no longer dumps useless items.
1209 lists only specific options.
1210 - --help=recursive, -hr
1211 displays the help of all the embedded packages.
1212 - Remembers environment variables when reconfiguring.
1213 The previous scheme to set envvar before running configure was
1215 what prevented configure from remembering the environment in which
1216 it was run, therefore --recheck was run in an inconsistent
1217 environment. Now, one should run
1219 and then --recheck will work properly. Variables declared with
1220 AC_ARG_VAR are also preserved.
1222 $build defaults to `config.guess`, $host to $build, and then $target
1224 Cross-compilation is a global status of the package, it no longer
1225 depends upon the current language.
1226 Cross compilation is enabled iff the user specified `--host'.
1227 `configure' now fails if it can't run the executables it compiles,
1228 unless cross-compilation is enabled.
1230 The cache file is disabled by default. The new options
1231 `--config-cache', `-C' set the cache to `config.cache'.
1235 Much faster on most architectures.
1236 - concurrent executions
1237 It is safe to use `make -j' with config.status.
1238 - human interface improved
1239 It is possible to invoke
1240 ./config.status foobar
1241 instead of the former form (still valid)
1242 CONFIG_COMMANDS= CONFIG_HEADERS= CONFIG_LINKS= \
1243 CONFIG_FILES=foobar:foo.in:bar.in \
1245 The same holds for configuration headers and links.
1246 You can instantiate unknown files and headers:
1247 ./config.status --header foo.h:foo.h.in --file bar:baz
1248 - has a useful --help
1249 - accepts special file name "-" for stdin/stdout
1254 Specify additional copyright information.
1257 Now expects the identity of the package as argument.
1261 Most macros, if not all, now strictly follow the `one quotation
1262 level' rule. This results in a more predictable expansion.
1265 A sly bug in the AC_REQUIRE machinery, which could produce incorrect
1266 configure scripts, was fixed by Axel Thimm.
1270 Document and ask for the registration of an envvar.
1273 Specifies the file which `configure' should look for when trying to
1274 find the source tree (used to be handled by AC_INIT).
1276 - AC_CONFIG_COMMANDS
1277 To add new actions to config.status. Should be used instead of
1281 Replaces AC_LINK_FILES.
1283 - AC_CONFIG_HEADERS, AC_CONFIG_COMMANDS, AC_CONFIG_SUBDIRS,
1284 AC_CONFIG_LINKS, and AC_CONFIG_FILES
1285 They now obey sh: you should no longer use shell variables as
1286 argument. Instead of
1288 test "$package_foo_enabled" = yes && $my_subdirs="$my_subdirs foo"
1289 AC_CONFIG_SUBDIRS($my_subdirs)
1293 if test "$package_foo_enabled" = yes; then
1294 AC_CONFIG_SUBDIRS(foo)
1298 To format an Autoconf macro's help string so that it looks pretty
1299 when the user executes `configure --help'.
1302 ** Generic Test Macros
1304 The interface of the AC_CHECK families of macros (decl, header,
1305 type, member, func) is now uniform. They support the same set of
1308 - AC_CHECK_DECL, AC_CHECK_DECLS
1309 To check whether a symbol is declared.
1311 - AC_CHECK_SIZEOF, AC_C_CHAR_UNSIGNED.
1312 No longer need a cross-compilation default.
1315 The test it performs is much more robust than previously, and makes
1316 it possible to test builtin types in addition to typedefs.
1317 It is now schizophrenic:
1318 - AC_CHECK_TYPE(TYPE, REPLACEMENT)
1319 remains for backward compatibility, but its use is discouraged.
1320 - AC_CHECK_TYPE(TYPE, IF-FOUND, IF-NOT-FOUND, INCLUDES)
1321 behaves exactly like the other AC_CHECK macros.
1324 Checks whether given types are supported by the system.
1326 - AC_CHECK_MEMBER, AC_CHECK_MEMBERS
1327 Check for given members in aggregates (e.g., pw_gecos in struct
1331 Checks if the compiler supports ISO C, included when needs special
1335 Checking whether the preprocessor indicates missing includes by the
1336 error code. stderr is checked by AC_TRY_CPP only as a fallback.
1339 Takes a language as argument and replaces AC_LANG_C,
1340 AC_LANG_CPLUSPLUS and AC_LANG_FORTRAN77.
1342 - AC_LANG_PUSH, AC_LANG_POP
1343 Are preferred to AC_LANG_SAVE, AC_LANG_RESTORE.
1346 - AC_FUNC_CHOWN, AC_FUNC_MALLOC, AC_FUNC_STRERROR_R,
1347 AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK, AC_FUNC_STAT, AC_FUNC_LSTAT,
1348 AC_FUNC_ERROR_AT_LINE, AC_FUNC_OBSTACK, AC_FUNC_STRTOD, AC_FUNC_FSEEKO.
1352 Sets GETGROUPS_LIBS.
1354 - AC_FUNC_GETLOADAVG
1355 Defines `HAVE_STRUCT_NLIST_N_UN_N_NAME' instead of `NLIST_NAME_UNION'.
1358 Now integrates `AC_DECL_YYTEXT' which is obsoleted.
1361 Arrange for large-file support.
1363 - AC_EXEEXT, AC_OBJEXT
1364 You are no longer expected to use them: their computation is
1365 performed by default.
1367 ** C++ compatibility
1368 Every macro has been revisited in order to support at best CC=c++.
1370 Major changes in Autoconf 2.14:
1371 There was no release of GNU Autoconf 2.14.
1373 Major changes in Autoconf 2.13:
1375 Released 1999-05-01 by Ben Elliston.
1377 * Support for building on Win32 systems where the only available C or
1378 C++ compiler is the Microsoft Visual C++ command line compiler
1379 (`cl'). Additional support for building on Win32 systems which are
1380 using the Cygwin or Mingw32 environments.
1381 * Support for alternative object file and executable file extensions.
1382 On Win32, for example, these are .obj and .exe. These are discovered
1383 using AC_OBJEXT and AC_EXEEXT, which substitute @OBJEXT@ and
1384 @EXEEXT@ in the output, respectively.
1385 * New macros: AC_CACHE_LOAD, AC_CACHE_SAVE, AC_FUNC_SELECT_ARGTYPES,
1386 AC_VALIDATE_CACHED_SYSTEM_TUPLE, AC_SEARCH_LIBS, AC_TRY_LINK_FUNC,
1387 AC_C_STRINGIZE, AC_CHECK_FILE(S), AC_PROG_F77 (and friends).
1388 * AC_DEFINE now has an optional third argument for a description to be
1389 placed in the config header input file (e.g. config.h.in).
1390 * The C++ code fragment compiled for the C++ compiler test had to be
1391 improved to include an explicit return type for main(). This was
1392 causing failures on systems using recent versions of the EGCS C++
1394 * Fixed an important bug in AC_CHECK_TYPE that would cause a configure
1395 script to report that `sometype_t' was present when only `type_t'
1397 * Merge of the FSF version of config.guess and config.sub to modernize
1398 these scripts. Add support for a few new hosts in config.guess.
1399 Incorporate latest versions of install-sh, mkinstalldirs and
1400 texinfo.tex from the FSF.
1401 * autoreconf is capable of running automake if necessary (and
1403 * Support for Fortran 77. See the Texinfo documentation for details.
1404 * Bug fixes and workarounds for quirky bugs in vendor utilities.
1406 Major changes in Autoconf 2.12:
1408 Released 1996-11-26 by David J. MacKenzie
1410 * AC_OUTPUT and AC_CONFIG_HEADER can create output files by
1411 concatenating multiple input files separated by colons, like so:
1412 AC_CONFIG_HEADER(config.h:conf.pre:config.h.in:conf.post)
1413 AC_OUTPUT(Makefile:Makefile.in:Makefile.rules)
1414 The arguments may be shell variables, to compute the lists on the fly.
1415 * AC_LINK_FILES and AC_CONFIG_SUBDIRS may be called multiple times.
1416 * New macro AC_OUTPUT_COMMANDS adds more commands to run in config.status.
1419 Major changes in Autoconf 2.11:
1421 Released November 18th, 1996, by David J. MacKenzie
1423 * AC_PROG_CC and AC_PROG_CXX check whether the compiler works.
1424 They also default CFLAGS/CXXFLAGS to "-g -O2" for gcc, instead of "-g -O".
1425 * AC_REPLACE_FUNCS defines HAVE_foo if the system has the function `foo'.
1426 * AC_CONFIG_HEADER expands shell variables in its argument.
1427 * New macros: AC_FUNC_FNMATCH, AC_FUNC_SETPGRP.
1428 * The "checking..." messages and the source code for test programs that
1429 fail are saved in config.log.
1430 * Another workaround has been added for seds with small command length limits.
1431 * config.sub and config.guess recognize more system types.
1434 Major changes in Autoconf 2.10:
1436 Released May 7th, 1996, by Roland McGrath
1439 * The cache variable names used by `AC_CHECK_LIB(LIB, FUNC, ...)' has
1440 changed: now $ac_cv_lib_LIB_FUNC, previously $ac_cv_lib_LIB.
1442 Major changes in Autoconf 2.9:
1444 Released March 16th, 1996, by Roland McGrath
1448 Major changes in Autoconf 2.8:
1450 Released March 8th, 1996, by Roland McGrath
1454 Major changes in Autoconf 2.7:
1456 Released November 22nd, 1995, by David J. MacKenzie
1460 Major changes in Autoconf 2.6:
1462 Released November 20th, 1995, by David J. MacKenzie
1466 Major changes in Autoconf 2.5:
1468 Released November 17th, 1995, by Roland McGrath
1470 * New configure options --bindir, --libdir, --datadir, etc., with
1471 corresponding output variables.
1472 * New macro: AC_CACHE_CHECK, to make using the cache easier.
1473 * config.log contains the command being run as well as any output from it.
1474 * AC_CHECK_LIB can check for libraries with "." or "/" or "+" in their name.
1475 * AC_PROG_INSTALL doesn't cache a name for install-sh, for sharing caches.
1476 * AC_CHECK_PROG, AC_PATH_PROG, AC_CHECK_PROGS, AC_PATH_PROGS, and
1477 AC_CHECK_TOOL can search a path other than $PATH.
1478 * AC_CHECK_SIZEOF takes an optional size to use when cross-compiling.
1480 Major changes in Autoconf 2.4:
1482 Released June 14th, 1995, by David J. MacKenzie
1484 * Fix a few bugs found by Emacs testers.
1486 Major changes in Autoconf 2.3:
1488 Released March 27th, 1995, by David J. MacKenzie
1490 * Fix the cleanup trap in several ways.
1491 * Handle C compilers that are picky about option placement.
1492 * ifnames gets the version number from the right directory.
1494 Major changes in Autoconf 2.2:
1496 Released March 8th, 1995, by David J. MacKenzie
1498 * The ifnames utility is much faster but requires a "new awk" interpreter.
1499 * AC_CHECK_LIB and AC_HAVE_LIBRARY check and add the new
1500 library before existing libs, not after, in case it uses them.
1501 * New macros: AC_FUNC_GETPGRP, AC_CHECK_TOOL.
1502 * Lots of bug fixes.
1503 * Many additions to the TODO file :-)
1505 Major changes in Autoconf 2.1:
1507 Released November 4th, 1994, by David J. MacKenzie
1510 * More explanations in the manual.
1511 * Fix a spurious failure in the testsuite.
1512 * Clarify some warning messages.
1513 * autoreconf by default only rebuilds configure and config.h.in files
1514 that are older than any of their particular input files; there is a
1515 --force option to use after installing a new version of Autoconf.
1517 Thanks to everybody who's submitted changes and additions to Autoconf!
1518 I've incorporated many of them, and am still considering others for
1519 future releases -- but I didn't want to postpone this release indefinitely.
1521 Caution: don't indiscriminately rebuild configure scripts with
1522 Autoconf version 2. Some configure.in files need minor adjustments to
1523 work with it; the documentation has a chapter on upgrading. A few
1524 configure.in files, including those for GNU Emacs and the GNU C
1525 Library, need major changes because they relied on undocumented
1526 internals of version 1. Future releases of those packages will have
1527 updated configure.in files.
1529 It's best to use GNU M4 1.3 (or later) with Autoconf version 2.
1530 Autoconf now makes heavy use of M4 diversions, which were implemented
1531 inefficiently in GNU M4 releases before 1.3.
1533 Major changes in Autoconf 2.0:
1535 Released October 26th, 1994, by David J. MacKenzie
1537 ** New copyright terms:
1538 * There are no restrictions on distribution or use of configure scripts.
1541 * Autoconf manual is reorganized to make information easier to find
1542 and has several new indexes.
1543 * INSTALL is reorganized and clearer and is now made from Texinfo source.
1546 * autoscan to generate a preliminary configure.in for a package by
1547 scanning its source code for commonly used nonportable functions,
1548 programs, and header files.
1549 * ifnames to list the symbols used in #if and #ifdef directives in a
1551 * autoupdate to update a configure.in to use the version 2 macro names.
1552 * autoreconf to recursively remake configure and configuration header
1553 files in a source tree.
1555 ** Changed utilities:
1556 * autoheader can take pieces of acconfig.h to replace config.h.{top,bot}.
1557 * autoconf and autoheader can look for package-local definition files
1558 in an alternate directory.
1561 * AC_CACHE_VAL to share results of tests between configure runs.
1562 * AC_DEFUN to define macros, automatically AC_PROVIDE them, and ensure
1563 that macros invoked with AC_REQUIRE don't interrupt other macros.
1564 * AC_CONFIG_AUX_DIR, AC_CANONICAL_SYSTEM, AC_CANONICAL_HOST, AC_LINK_FILES to
1565 support deciding unguessable features based on the host and target types.
1566 * AC_CONFIG_SUBDIRS to recursively configure a source tree.
1567 * AC_ARG_PROGRAM to use the options --program-prefix,
1568 --program-suffix, and --program-transform-name to change the names
1569 of programs being installed.
1570 * AC_PREFIX_DEFAULT to change the default installation prefix.
1571 * AC_TRY_COMPILE to compile a test program without linking it.
1572 * AC_CHECK_TYPE to check whether sys/types.h or stdlib.h defines a given type.
1573 * AC_CHECK_LIB to check for a particular function and library.
1574 * AC_MSG_CHECKING and AC_MSG_RESULT to print test results, on a single line,
1575 whether or not the test succeeds. They obsolete AC_CHECKING and AC_VERBOSE.
1576 * AC_SUBST_FILE to insert one file into another.
1577 * AC_FUNC_MEMCMP to check whether memcmp is 8-bit clean.
1578 * AC_FUNC_STRFTIME to find strftime even if it's in -lintl.
1579 * AC_FUNC_GETMNTENT to find getmntent even if it's in -lsun or -lseq.
1580 * AC_HEADER_SYS_WAIT to check whether sys/wait.h is POSIX.1 compatible.
1583 * Many macros renamed systematically, but old names are accepted for
1584 backward compatibility.
1585 * AC_OUTPUT adds the "automatically generated" comment to
1586 non-Makefiles where it finds @configure_input@ in an input file, to
1587 support files with various comment syntaxes.
1588 * AC_OUTPUT does not replace "prefix" and "exec_prefix" in generated
1589 files when they are not enclosed in @ signs.
1590 * AC_OUTPUT allows the optional environment variable CONFIG_STATUS to
1591 override the file name "config.status".
1592 * AC_OUTPUT takes an optional argument for passing variables from
1593 configure to config.status.
1594 * AC_OUTPUT and AC_CONFIG_HEADER allow you to override the input-file names.
1595 * AC_OUTPUT automatically substitutes the values of CFLAGS, CXXFLAGS,
1596 CPPFLAGS, and LDFLAGS from the environment.
1597 * AC_PROG_CC and AC_PROG_CXX now set CFLAGS and CXXFLAGS, respectively.
1598 * AC_PROG_INSTALL looks for install-sh or install.sh in the directory
1599 specified by AC_CONFIG_AUXDIR, or srcdir or srcdir/.. or
1600 srcdir/../.. by default.
1601 * AC_DEFINE, AC_DEFINE_UNQUOTED, and AC_SUBST are more robust and smaller.
1602 * AC_DEFINE no longer prints anything, because of the new result reporting
1603 mechanism (AC_MSG_CHECKING and AC_MSG_RESULT).
1604 * AC_VERBOSE pays attention to --quiet/--silent, not --verbose.
1605 * AC_ARG_ENABLE and AC_ARG_WITH support whitespace in the arguments to
1606 --enable- and --with- options.
1607 * AC_CHECK_FUNCS and AC_CHECK_HEADERS take optional shell commands to
1608 execute on success or failure.
1609 * Checking for C functions in C++ works.
1612 * AC_REMOTE_TAPE and AC_RSH removed; too specific to tar and cpio, and
1613 better maintained with them.
1614 * AC_ARG_ARRAY removed because no one was likely using it.
1615 * AC_HAVE_POUNDBANG replaced with AC_SYS_INTERPRETER, which doesn't
1616 take arguments, for consistency with all of the other specific checks.
1619 * Comes with config.sub and config.guess, and uses them optionally.
1620 * Uses config.cache to cache test results. An alternate cache file
1621 can be selected with the --cache-file=FILE option.
1622 * Uses optional shell scripts $prefix/share/config.site and
1623 $prefix/etc/config.site to perform site or system specific initializations.
1624 * configure saves compiler output to ./config.log for debugging.
1625 * New files autoconf.m4 and autoheader.m4 load the other Autoconf macros.
1626 * acsite.m4 is the new name for the system-wide aclocal.m4.
1627 * Has a DejaGnu test suite.
1629 Major changes in Autoconf 1.11:
1631 * AC_PROG_INSTALL calls install.sh with the -c option.
1632 * AC_SET_MAKE cleans up after itself.
1633 * AC_OUTPUT sets prefix and exec_prefix if they weren't set already.
1634 * AC_OUTPUT prevents shells from looking in PATH for config.status.
1636 Plus a few other bug fixes.
1638 Major changes in Autoconf 1.10:
1640 * autoheader uses config.h.bot if present, analogous to config.h.top.
1641 * AC_PROG_INSTALL looks for install.sh in srcdir or srcdir/.. and
1643 * AC_PROG_CXX looks for cxx as a C++ compiler.
1645 Plus several bugs fixed.
1647 Major changes in Autoconf 1.9:
1649 * AC_YYTEXT_POINTER replaces AC_DECLARE_YYTEXT.
1650 * AC_SIZEOF_TYPE generates the cpp symbol name automatically,
1651 and autoheader generates entries for those names automatically.
1652 * AC_FIND_X gets the result from xmkmf correctly.
1653 * AC_FIND_X assumes no X if --without-x was given.
1654 * AC_FIND_XTRA adds libraries to the variable X_EXTRA_LIBS.
1655 * AC_PROG_INSTALL finds OSF/1 installbsd.
1657 Major changes in Autoconf 1.8:
1660 * New macros AC_LANG_C, AC_LANG_CPLUSPLUS, AC_LANG_SAVE, AC_LANG_RESTORE,
1661 AC_PROG_CXX, AC_PROG_CXXCPP, AC_REQUIRE_CPP
1662 for checking both C++ and C features in one configure script.
1663 * New macros AC_CHECKING, AC_VERBOSE, AC_WARN, AC_ERROR for printing messages.
1664 * New macros AC_FIND_XTRA, AC_MMAP, AC_SIZEOF_TYPE, AC_PREREQ,
1665 AC_SET_MAKE, AC_ENABLE.
1668 * AC_FIND_X looks for X in more places.
1669 * AC_PROG_INSTALL defaults to install.sh instead of cp, if it's in srcdir.
1670 install.sh is distributed with Autoconf.
1671 * AC_DECLARE_YYTEXT has been removed because it can't work, pending
1672 a rewrite of quoting in AC_DEFINE.
1673 * AC_OUTPUT adds its comments in C format when substituting in C files.
1674 * AC_COMPILE_CHECK protects its ECHO-TEXT argument with double quotes.
1676 ** New or changed command line options:
1677 * configure accepts --enable-FEATURE[=ARG] and --disable-FEATURE options.
1678 * configure accepts --without-PACKAGE, which sets withval=no.
1679 * configure accepts --x-includes=DIR and --x-libraries=DIR.
1680 * Giving --with-PACKAGE no argument sets withval=yes instead of withval=1.
1681 * configure accepts --help, --version, --silent/--quiet, --no-create options.
1682 * configure accepts and ignores most other Cygnus configure options, and
1683 warns about unknown options.
1684 * config.status accepts --help, --version options.
1686 ** File names and other changes:
1687 * Relative srcdir values are not made absolute.
1688 * The values of @prefix@ and @exec_prefix@ and @top_srcdir@ get substituted.
1689 * Autoconf library files are installed in ${datadir}/autoconf, not ${datadir}.
1690 * autoheader optionally copies config.h.top to the beginning of config.h.in.
1691 * The example Makefile dependencies for configure et al. work better.
1692 * Namespace cleanup: all shell variables used internally by Autoconf
1693 have names beginning with `ac_'.
1695 More big improvements are in process for future releases, but have not
1696 yet been (variously) finished, integrated, tested, or documented enough
1699 Major changes in Autoconf 1.7:
1701 * New macro AC_OBSOLETE.
1702 * Bugs in Makefile.in fixed.
1703 * AC_LONG_FILE_NAMES improved.
1705 Major changes in Autoconf 1.6:
1707 * New macro AC_LONG_64_BITS.
1708 * Multiple .h files can be created.
1709 * AC_FIND_X looks for X files directly if it doesn't find xmkmf.
1710 * AC_ALLOCA defines C_ALLOCA if using alloca.c.
1711 * --with-NAME can take a value, e.g., --with-targets=sun4,hp300bsd.
1712 * Unused --no-create option to configure removed.
1713 * autoheader doesn't change the timestamp of its output file if
1714 the file didn't change.
1715 * All macros that look for libraries now use AC_HAVE_LIBRARY.
1716 * config.status checks three optional environment variables to
1717 modify its behavior.
1718 * The usual bug fixes.
1720 Major changes in Autoconf 1.5:
1722 * New macros AC_FIND_X, AC_OFF_T, AC_STAT_MACROS_BROKEN, AC_REVISION.
1723 * autoconf and autoheader scripts have GNU standards conforming
1724 --version and --help options (they print their message and exit).
1727 Major changes in Autoconf 1.4:
1729 * New macros AC_HAVE_POUNDBANG, AC_TIME_WITH_SYS_TIME, AC_LONG_DOUBLE,
1730 AC_GETGROUPS_T, AC_DEFINE_UNQUOTED.
1731 * autoconf and autoheader use the M4 environment variable to determine the
1732 name of the M4 program to use.
1733 * The --macrodir option to autoconf and autoheader specifies the directory
1734 in which acspecific.m4, acgeneral.m4, etc. reside if not the default.
1735 * autoconf and autoheader can take `-' as their file names, which means to
1736 read stdin as input.
1737 * Resulting configure scripts can take a --verbose option which causes them
1738 to print the results of their tests.
1739 * AC_DEFINE quotes its second argument in such a way that spaces, magic
1740 shell characters, etc. will be preserved during various stages of
1741 expansion done by the shell. If you don't want this, use
1742 AC_DEFINE_UNQUOTED instead.
1743 * Much textual processing done with external calls to tr and sed have been
1744 internalized with builtin M4 `patsubst' and `translit' calls.
1745 * AC_OUTPUT doesn't hardwire the file names it outputs. Instead, you can
1746 set the shell variables `gen_files' and `gen_config' to the list of
1747 file names to output.
1748 * AC_DECLARE_YYTEXT does an AC_SUBST of `LEX_OUTPUT_ROOT', which may be
1749 "lex.yy" or "lexyy", depending on the system.
1750 * AC_PROGRAMS_CHECK takes an optional third arg. If given, it is used as
1752 * If AC_ALLOCA chooses alloca.c, it also defines STACK_DIRECTION.
1753 * AC_CONST works much more reliably on more systems.
1756 Major changes in Autoconf 1.3:
1758 configure no longer requires awk for packages that use a config.h.
1759 Support handling --with-PACKAGE options.
1760 New `autoheader' script to create `config.h.in' from `configure.in'.
1761 Ignore troublesome -lucb and -lPW when searching for alloca.
1762 Rename --exec_prefix to --exec-prefix for GNU standards conformance.
1763 Improve detection of STDC library.
1764 Add AC_HAVE_LIBRARY to check for non-default libraries.
1765 Function checking should work with future GNU libc releases.
1767 Major changes in Autoconf 1.2:
1769 The --srcdir option is now usually unnecessary.
1770 Add a file containing sample comments describing CPP macros.
1771 A comment in config.status tells which host it was configured on.
1772 Substituted variable values can now contain commas.
1773 Fix bugs in various feature checks.
1775 Major changes in Autoconf 1.1:
1777 Added AC_STRCOLL macro.
1778 Made AC_GETLOADAVG check for more things.
1779 AC_OUTPUT argument is now optional.
1784 Copyright (C) 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002,
1785 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
1787 This program is free software: you can redistribute it and/or modify
1788 it under the terms of the GNU General Public License as published by
1789 the Free Software Foundation, either version 3 of the License, or
1790 (at your option) any later version.
1792 This program is distributed in the hope that it will be useful,
1793 but WITHOUT ANY WARRANTY; without even the implied warranty of
1794 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1795 GNU General Public License for more details.
1797 You should have received a copy of the GNU General Public License
1798 along with this program. If not, see <http://www.gnu.org/licenses/>.