1 GNU Autoconf NEWS - User visible changes.
3 * Major changes in Autoconf 2.64a (????-??-??) [experimental]
6 ** Autoconf is now licensed under the General Public License version 3
7 or later (GPLv3+). As with earlier versions, the license includes
8 an exception clause so that you may release a configure script
9 generated by autoconf under the license of your own program.
11 ** New macros to support Objective C++.
12 AC_PROG_OBJCXX AC_PROG_OBJCXXCPP
14 ** The following undocumented autoconf macros, removed in Autoconf 2.64,
18 These macros are present only for backwards compatibility purposes.
20 ** The AC_FC_FREEFORM macro no longer suffers from a whitespace bug that
21 made it fail with some Fortran compilers (regression introduced in
24 ** The AC_TYPE_UINT64_T and AC_TYPE_INT64_T macros have been fixed to no
25 longer mistakenly select a 32-bit type on some compilers (bug present
26 since macros were introduced in 2.59c).
28 ** The following documented autotest macros are new:
31 ** The following m4sugar macros now quote their expansion:
34 ** The `$tmp' temporary directory used in config.status is documented for
37 ** config.status now provides a --config option to produce the configuration.
39 ** Many cache variables used by Autoconf's macros are now documented.
41 * Major changes in Autoconf 2.64 (2009-07-26) [stable]
42 Released by Eric Blake, based on git versions 2.63b.*.
44 ** Autoconf now requires GNU M4 1.4.6 or later. Earlier versions of M4
45 have a bug in regular expression handling that interferes with some
46 of the speedups provided since Autoconf 2.63. GNU M4 1.4.13 or
49 ** AS_IF and AS_CASE have been taught to avoid syntax errors even when
50 given arguments that expand to just whitespace.
52 ** The following documented autoconf macros are new:
53 AC_ERLANG_SUBST_ERTS_VER
55 ** The autoheader tool now understands m4 macro arguments passed to
56 AC_DEFINE and AC_DEFINE_UNQUOTED.
58 ** Ensure AT_CHECK can support commands that include a # given with
59 proper m4 quoting. For shell comments, this is a new feature; for
60 non-shell comments, this fixes a regression introduced in 2.63b.
61 Additionally, AT_CHECK correctly supplies shell escapes for
62 metacharacters occurring in m4 macro expansions within the expected
63 stdout and stderr parameters.
65 ** The macro AT_CHECK now understands the concept of hard failure. If
66 a test exits with an unexpected status 99, cleanup actions for the
67 test are inhibited and the test is treated as a failure regardless
68 of AT_XFAIL_IF. It also understands the new directives
69 ignore-nolog, stdout-nolog, and stderr-nolog.
71 ** The following documented autotest macros are new:
72 AT_CHECK_UNQUOTED AT_FAIL_IF AT_SKIP_IF
74 ** The following documented m4sugar macros are new:
75 m4_argn m4_copy_force m4_default_nblank m4_default_nblank_quoted
76 m4_ifblank m4_ifnblank m4_rename_force
78 ** The autoconf testsuite now exercises all Erlang macros.
80 * Major changes in Autoconf 2.63b (2009-03-31) [beta]
81 Released by Eric Blake, based on git versions 2.63.*.
83 ** The manual is now shipped under the terms of the GNU FDL 1.3.
85 ** AC_REQUIRE now detects the case of an outer macro which first expands
86 then later indirectly requires the same inner macro. Previously,
87 this case led to silent out-of-order expansion (bug present since
88 2.50); it now issues a syntax warning, and duplicates the expansion
89 of the inner macro to guarantee dependencies have been met. See
90 the manual for advice on how to refactor macros in order to avoid
91 the bug in earlier autoconf versions and avoid increased script
92 size in the current version.
94 ** AC_DEFUN_ONCE has improved semantics. Previously, a macro declared
95 with AC_DEFUN_ONCE warned on a second invocation; and out-of-order
96 expansion was still possible. Now, dependencies are guaranteed,
97 and subsequent invocations are a silent no-op. This makes
98 AC_DEFUN_ONCE an ideal macro for silencing AC_REQUIRE warnings.
100 ** The following macros are now defined with AC_DEFUN_ONCE. This means
101 a subtle change in semantics; previously, an AC_DEFUN macro could
102 expand one of these macros multiple times or surround the macro
103 inside shell conditional text to bypass the effects of these
104 macros, but now the macro will expand exactly once, and prior to
105 the start of any enclosing AC_DEFUN macro:
106 AC_CANONICAL_BUILD AC_CANONICAL_HOST AC_CANONICAL_TARGET
107 AC_HEADER_ASSERT AC_PROG_INSTALL AC_PROG_MKDIR_P
108 AC_USE_SYSTEM_EXTENSIONS
110 ** AC_LANG_ERLANG works once again (regression introduced in 2.61a).
112 ** AC_HEADER_ASSERT is fixed so that './configure --enable-assert' no
113 longer mistakenly disables assertions.
115 ** AC_INIT now takes an optional fifth parameter that can be used to
116 set AC_PACKAGE_URL, a URL for the package's home page; the URL is
117 used in `configure --help' and is also available via AC_DEFINE.
119 ** Autotest testsuites accept an option --jobs[=N] for parallel testing.
120 This feature is still in testing, and may not work on every
121 platform, help in improving it would be appreciated.
123 ** Autotest testsuites do not attempt to write startup error messages
124 to the log file before that is opened (regression introduced in 2.63).
126 ** Configure scripts now use shell functions. This feature leads to
127 smaller configure files and faster execution.
129 ** Present But Cannot Be Compiled: Autoconf will now proceed with
130 the compiler's result if a header is present but cannot be compiled.
131 The warning is still printed, and you should really fix it by
132 providing a fourth parameter to AC_CHECK_HEADER/AC_CHECK_HEADERS.
134 ** Autoreconf added aclocal to the set of programs affected by the
135 `autoreconf -I dir' option.
137 ** The following documented m4sugar macros are new:
138 m4_chomp m4_chomp_all m4_cleardivert m4_curry m4_default_quoted
139 m4_esyscmd_s m4_map_args m4_map_args_pair m4_map_args_sep
140 m4_map_args_w m4_set_map m4_set_map_sep m4_stack_foreach
141 m4_stack_foreach_lifo m4_stack_foreach_sep
142 m4_stack_foreach_sep_lifo
144 ** The following m4sugar macros are documented now, but in some cases
145 with slightly different semantics than what the previous
146 undocumented version had:
147 m4_copy m4_dumpdefs m4_rename m4_version_prereq
149 ** The m4sugar macro m4_expand has been taught to handle unterminated
150 comments and shell case statements. As a result, it is used
151 internally in more places, such as AC_DEFINE and AT_CHECK. Most
152 uses of AC_DEFINE and AT_CHECK should not behave any differently;
153 however, it may be necessary to add double-quoting around
154 unbalanced `(' where single-quoting used to be sufficient.
156 ** The following documented m4sh macros are new:
157 AS_INIT_GENERATED AS_LINENO_PREPARE AS_ME_PREPARE AS_SET_STATUS
158 AS_VAR_APPEND AS_VAR_ARITH AS_VAR_COPY
160 ** The following m4sh macros are documented now, but in some cases
161 with slightly different semantics than what the previous
162 undocumented version had:
163 AS_ECHO AS_ECHO_N AS_ESCAPE AS_EXIT AS_LITERAL_IF AS_UNSET
164 AS_VAR_IF AS_VAR_POPDEF AS_VAR_PUSHDEF AS_VAR_SET AS_VAR_SET_IF
165 AS_VAR_TEST_SET AS_VERSION_COMPARE
167 ** The m4sh macros AS_IF and AS_CASE can now be used in shell lists.
168 The responsibility for supplying a trailing newline now belongs to
169 the call site, but since most users did not add dnl, this generally
170 results in fewer empty lines in configure.
173 * Major changes in Autoconf 2.63 (2008-09-09) [stable]
174 Released by Eric Blake, based on git versions 2.62.*.
176 ** AC_C_BIGENDIAN does not mistakenly report "universal" for some
177 bigendian hosts, a regression introduced with universal binary
180 ** AC_PATH_X now includes /lib64 and /usr/lib64 in its list of default
183 ** AC_USE_SYSTEM_EXTENSIONS no longer conflicts with an external
184 AC_DEFINE([__EXTENSIONS__]). This fixes a regression introduced in
185 2.62 when using macros such as AC_AIX that were made obsolete in
186 favor of the more portable AC_USE_SYSTEM_EXTENSIONS.
188 ** AC_CHECK_TARGET_TOOLS is usable in the non-cross-compile case.
190 ** Newly obsolete macros
191 The following macro has been marked obsolete, since current porting
192 targets can safely assume C89 semantics that signal handlers return
193 void. We have no current plans to remove the macro.
197 ** The macros m4_map and m4_map_sep now ignore any list elements
198 consisting of just empty quotes, and m4_map_sep now expands its
199 separator. This fixes a regression in 2.62 when these macros were
200 first documented, for the sake of clients expecting the semantics
201 that these macros had prior to that time. The new macros m4_mapall
202 and m4_mapall_sep, along with extra quoting of the separator, can
203 be used to get the semantics that m4_map_sep had in 2.62.
205 ** Clients of m4_expand, such as AS_HELP_STRING and AT_SETUP, can now
206 handle properly quoted but otherwise unbalanced parentheses (for
207 some macros, this fixes a regression in 2.62).
209 ** Two new quadrigraphs have been introduced: @{:@ for (, and @:}@ for ),
210 allowing the output of unbalanced parentheses in more contexts.
212 ** The following m4sugar macros are new:
213 m4_cleardivert m4_joinall m4_mapall m4_mapall_sep m4_reverse
214 m4_set_add m4_set_add_all m4_set_contains m4_set_contents
215 m4_set_delete m4_set_difference m4_set_dump m4_set_empty
216 m4_set_foreach m4_set_intersection m4_set_list m4_set_listc
217 m4_set_remove m4_set_size m4_set_union
219 ** The following m4sugar macros now accept multiple arguments, as is the
220 case with underlying m4:
221 m4_defn m4_popdef m4_undefine
223 ** The following m4sugar macros now guarantee linear scaling; they
224 previously had linear scaling with m4 1.6 but quadratic scaling
225 when using m4 1.4.x. All macros built on top of these also gain
226 the scaling improvements.
227 m4_bmatch m4_bpatsubsts m4_case m4_cond m4_do m4_dquote_elt
228 m4_foreach m4_join m4_list_cmp m4_map m4_map_sep m4_max
231 ** AT_KEYWORDS once again performs expansion on its argument, such that
232 AT_KEYWORDS([m4_if([$1], [], [default])]) no longer complains about
233 the possibly unexpanded m4_if [regression introduced in 2.62].
235 ** Config header templates `#undef UNDEFINED /* comment */' do not lead to
236 nested comments any more; regression introduced in 2.62.
239 * Major changes in Autoconf 2.62 (2008-04-05) [stable]
240 Released by Eric Blake, based on git versions 2.61a.*.
242 ** Many optimizations have been applied to make overall execution faster.
244 ** Autotest now makes use of shell functions.
246 ** config.status now uses awk instead of sed also for config headers.
248 - As a side effect, AC_DEFINE and AC_DEFINE_UNQUOTED now handle multi-line
249 values, i.e., backslash-newline combinations are handled correctly.
250 Further, for config headers, the total size of values is not limited by
251 the POSIX length limit of text lines any more, only each single line.
253 ** New config variable `top_build_prefix'.
255 ** New Autoconf macros:
256 AC_AUTOCONF_VERSION AC_OPENMP AC_PATH_PROGS_FEATURE_CHECK
258 ** AC_C_BIGENDIAN now supports universal binaries a la Mac OS X.
260 ** AC_C_RESTRICT now prefers to #define 'restrict' to a variant spelling
261 like '__restrict' if the variant spelling is available, as this is
262 more likely to work when mixing C and C++ code.
264 ** AC_CHECK_ALIGNOF's type argument T is now documented better: it must
265 be a string of tokens such that "T y;" is a valid member declaration
268 ** AC_CHECK_SIZEOF now accepts objects as well as types: the general rule
269 is that sizeof (X) works, then AC_CHECK_SIZEOF (X) should work.
271 ** AC_CHECK_TYPE and AC_CHECK_TYPES now work on any C type-name; formerly,
272 they did not work for function types. In C++, they now work on any
273 type-id that can be the operand of sizeof; this is similar to C,
274 except it excludes anonymous struct and union types. Formerly,
275 some (but not all) C++ types involving anonymous struct and union
276 were accepted, though this was not documented.
278 ** AC_CONFIG_LINKS now prefers to link against files in the build tree
279 if found, and it works to link against a file of the same name in
280 the source tree, even if both trees coincide.
282 ** AC_INIT no longer alters $@; regression introduced in 2.60.
284 ** AC_USE_SYSTEM_EXTENSIONS now defines _ALL_SOURCE for Interix platforms.
286 ** AS_HELP_STRING no longer underquotes its first argument; it also handles
287 the case where the first argument contains single-quoted commas.
288 For example, "AS_HELP_STRING([-a, [--arg[=foo]]], [bar])" produces:
289 " -a, --arg[=foo] bar"
290 Additionally, the macro now takes two additional arguments,
291 indent-column and wrap-column; these should not normally be needed,
292 but can be used to fine-tune how the output text is wrapped.
294 ** AC_PROG_INSTALL now requires an install program that can install multiple
295 files into a target directory.
297 ** The command 'autoconf -' now correctly processes a file from stdin.
299 ** 'autoreconf -m' now honors $MAKE.
301 ** For all of the directory arguments for 'configure', such as '--prefix'
302 or '--bindir', trailing slashes are stripped. As an example, if
303 tab completion in the user's shell appends trailing slashes, the
304 command './configure --prefix=/usr/' will still result in an
305 expanded libdir value of /usr/lib, not /usr//lib.
307 ** `configure --help=recursive' now works in read-only trees and from
308 unconfigured build trees.
310 ** If precious variables differ only in whitespace, then the cache consistency
311 check warns instead of fails, and reuses the old value.
313 ** AT_BANNER is now documented.
315 ** AT_SETUP now handles macro expansions properly when calculating line
318 ** Autotest now determines $srcdir correctly.
320 ** Testsuites built by autotest now accept a -C/--directory=DIR option
321 to adjust the working directory prior to creating files.
323 ** Autoconf now requires GNU M4 1.4.5 or later. Earlier versions of M4 have
324 a bug in macro tracing that interferes with the interaction between
325 Autoconf and Automake. GNU M4 1.4.11 or later is recommended. The
326 configure search for a working M4 is improved.
328 ** For portability with the eventual M4 2.0, macros should no longer use
329 anything larger than $9 to refer to arguments.
331 ** Documentation for m4sugar is improved.
333 - The following macros were previously available as undocumented
334 interfaces; the macros are now documented as stable interfaces.
336 __oline__ m4_assert m4_bmatch m4_bpatsubsts m4_car m4_case
337 m4_cdr m4_default m4_divert_once m4_divert_pop m4_divert_push
338 m4_divert_text m4_do m4_errprintn m4_fatal m4_flatten
339 m4_ifndef m4_ifset m4_ifval m4_ifvaln m4_location
340 m4_n m4_shiftn m4_strip m4_warn
342 - The following macros were previously available as undocumented
343 interfaces, but had bug fixes or semantic changes as part of this
344 release. Packages that relied on the undocumented behavior
345 should be analyzed to make sure they will still work with the
346 new documented behavior.
348 m4_cmp m4_list_cmp m4_join m4_map m4_map_sep m4_sign
349 m4_text_box m4_text_wrap m4_version_compare
351 - The m4_wrap macro used to have unspecified order, but now
352 guarantees FIFO order. m4_wrap_lifo was added to guarantee LIFO
355 - Packages using the undocumented m4sugar macro m4_PACKAGE_VERSION
356 should consider using the new AC_AUTOCONF_VERSION instead.
358 - m4sugar macros that are not documented in the manual are still
359 deemed experimental, and should not be used outside of Autoconf.
361 ** The m4sugar macros m4_append and m4_append_uniq, first documented in
362 2.60, have been fixed to treat both the string and the separator
363 arguments consistently with regards to quoting. Prior to this fix,
364 m4_append_uniq could mistakenly duplicate entries if the expansion
365 of the separator resulted in a different string (for example, if it
366 contained quotes, a comma, or a macro name). However, it means
367 that programs previously using
368 m4_append([name], [string], [[, ]])
369 are now using a four-character separator instead of the intended
370 comma and space. If you need portability to earlier versions of
371 Autoconf, you can insert the following snippet after AC_INIT but
372 before any other macro expansions, to enforce the new semantics:
373 m4_pushdef([m4_append], [m4_define([$1],
374 m4_ifdef([$1], [m4_defn([$1])[$3]])[$2])])
375 Additionally, m4_append_uniq now takes optional parameters that can
376 be used to take action depending on whether anything was appended,
377 and warns if a non-empty separator occurs within the string being
378 appended, since that can lead to duplicates.
380 ** The following m4sugar macros are new:
381 m4_append_uniq_w m4_apply m4_combine m4_cond m4_count
382 m4_dquote_elt m4_echo m4_expand m4_ignore m4_make_list m4_max
383 m4_min m4_newline m4_shift2 m4_shift3 m4_unquote m4_wrap_lifo
385 ** Warnings are now generated by default when an installer invokes
386 'configure' with an unknown --enable-* or --with-* option.
387 These warnings can be disabled with the new AC_DISABLE_OPTION_CHECKING
388 macro, or by invoking 'configure' with --disable-option-checking.
390 ** Existing obsolete macros
391 The documentation for the following macros is adjusted to make it
392 more clear that they have previously been marked obsolete, as their
393 functionality can be accomplished by other macros. We have no
394 current plans to remove them from Autoconf.
396 AC_ENABLE AC_STRUCT_ST_BLKSIZE AC_STRUCT_ST_RDEV AC_WITH
398 ** Newly obsolete macros
399 The following macros have been marked obsolete, as they only
400 perform a subset of AC_USE_SYSTEM_EXTENSIONS. We have no current
401 plans to remove them.
403 AC_AIX AC_GNU_SOURCE AC_ISC_POSIX AC_MINIX
405 ** AC_C_LONG_DOUBLE is obsolescent.
406 The documentation now says that AC_C_LONG_DOUBLE is obsolescent: it
407 tests for problems that are so old that it is no longer of
408 practical importance on current systems. New programs need not use
409 AC_C_LONG_DOUBLE. We have no current plans to remove it.
411 ** AC_DIAGNOSE, AC_WARNING, and AC_FATAL are obsolescent.
412 The documentation now favors the use of M4sugar macros m4_warn and
413 m4_fatal, since the naming makes it more obvious that the
414 diagnostics are associated with M4 expansion (ie. when running
415 `autoconf'), and offers less confusion with the AC_MSG_ERROR,
416 AC_MSG_FAILURE, and AC_MSG_WARN macros which manage diagnostics
417 when running `configure'. We have no current plans to remove these
421 * Major changes in Autoconf 2.61a (2006-12-11)
423 ** AC_FUNC_FSEEKO was broken in 2.61; it didn't make fseeko and ftello visible
424 on many platforms. This has been fixed.
426 ** AC_FUNC_SETVBUF_REVERSED is now obsolete. It is still defined for backward
427 compatibility but it does nothing. The macro was already
428 obsolescent, as the last systems to have the problem were those
429 based on SVR2, which became obsolete in 1987. The macro had bugs
430 on some modern systems and could no longer be maintained reliably
431 due to lack of ancient systems to test it on.
433 ** config.status now uses awk instead of sed for most substitutions, for speed.
435 - As a side effect multi-line values of substituted variables no
436 longer have a small limit in total size, though for portability
437 each line should not exceed the POSIX length limit for text lines.
439 - It is now documented that Makefile.in should not contain
440 overlapping variable occurrences, e.g., @VAR1@VAR2@.
441 Autoconf's behavior was always iffy in such cases, and the
442 awk implementation has changed the behavior.
444 ** Many uses of 'echo' have been rewritten so that Autoconf-generated
445 scripts have fewer problems with strings or file names containing
446 embedded special characters such as backslash or leading "-". This
447 was implemented by using `printf '%s\n' "$foo"' instead of `echo
448 "$foo"' when printf works. Due to the implementation technique
449 used, Autoconf-generated scripts now run considerably more slowly
450 on ancient implementations lacking printf. However, this should
451 not be a problem, since Autoconf-generated scripts in practice
452 invariably find a more-modern shell these days.
455 * Major changes in Autoconf 2.61 (2006-11-17)
457 ** New macros AC_C_FLEXIBLE_ARRAY_MEMBER, AC_C_VARARRAYS.
459 ** AC_ARG_ENABLE and AC_ARG_WITH now allow '.' in feature and package names.
462 * Major changes in Autoconf 2.60b (2006-10-22)
465 Autoconf-generated shell scripts no longer export BIN_SH, due to
466 configuration hassles with this. Installers who need BIN_SH in
467 their environment should set it before invoking 'configure' and
468 'make'. As far as we know, this affects only Unixware installations.
470 ** Obsolescent macros
471 The documentation now says that the following macros are obsolescent,
472 as they are superseded by Gnulib:
474 AC_FUNC_FNMATCH AC_FUNC_FNMATCH_GNU AC_FUNC_GETLOADVG AC_REPLACE_FNMATCH
476 New programs should use the Gnulib counterparts of these macros.
477 We have no current plans to remove them from Autoconf.
479 ** AC_COMPUTE_INT no longer caches or reports results.
481 ** AC_CHECK_DECL now also works with aggregate objects.
483 ** AC_USE_SYSTEM_EXTENSIONS now defines _TANDEM_SOURCE for NonStop platforms.
485 ** GNU M4 1.4.7 or later is now recommended.
488 New M4sugar macro, which is more secure than the POSIX M4 maketemp.
491 Now an alias for m4_mkstemp.
493 * Major changes in Autoconf 2.60a (2006-08-25)
495 ** GNU M4 1.4.6 or later is now recommended.
497 ** The check for C99 now tests for varargs macros, as documented.
498 It also tests that the preprocessor supports 64-bit integers.
500 ** Autoconf now uses constructs like "#ifdef HAVE_STDLIB_H" rather than
501 "#if HAVE_STDLIB_H", so that it now works with "gcc -Wundef -Werror".
503 ** The functionality of the undocumented _AC_COMPUTE_INT is now provided
504 by a public and documented macro, AC_COMPUTE_INT. The parameters to the
505 two macros are different, so autoupdate will not change the old private name
506 to the new one. _AC_COMPUTE_INT may be removed in a future release.
508 ** AC_TYPE_LONG_LONG_INT and AC_TYPE_UNSIGNED_LONG_LONG_INT now require
509 that long long types be at least 64 bits wide, as C99 and tradition
510 requires. Formerly, they accepted implementations of any width.
513 * Major changes in Autoconf 2.60
515 Released 2006-06-23, by Ralf Wildenhues.
517 ** Autoconf no longer depends on whether m4wrap is FIFO (as Posix requires)
518 or LIFO (as in GNU M4 1.4.x). GNU M4 2.0 is expected to conform to Posix
519 here, so m4wrap/m4_wrap users should no longer depend on LIFO behavior.
521 ** Provide a way to turn off warnings about the changed directory variables.
523 * Major changes in Autoconf 2.59d
525 Released 2006-06-05, by Ralf Wildenhues.
527 ** GNU make now recommended for VPATH builds
528 INSTALL now suggests VPATH builds (e.g., "sh ../srcdir/configure")
529 only if you use GNU make. In practice, other 'make' implementations
530 have too many subtle incompatibilities in their support for VPATH.
531 Many packages (including Autoconf itself) are portable to other
532 'make' implementations, but some packages are not, and recommending
533 GNU make keeps the installation instructions simpler.
535 ** Even more safety checks for the new Directory variables:
536 Warn about suspicious `${datarootdir}' found in config files output.
538 ** AC_TRY_COMMAND, AC_TRY_EVAL, ac_config_guess, ac_config_sub, ac_configure
539 These never-documented macros and variables have been marked with
540 comments saying that they may be removed in a future release,
541 because their use can lead to unintended code being executed.
542 If you need functionality that only these macros or variables
543 currently supply, please write bug-autoconf@gnu.org.
545 ** AC_SUBST, AC_DEFINE
546 Literal arguments to these are passed to m4_pattern_allow now.
549 Passing 'ac_cv_prog_cc_stdc=no' to 'configure' now sets ac_cv_prog_cc_c99
550 and ac_cv_prog_cc_c89 to 'no' as well, for backward compatibility with
551 obsolete K&R tests in the Automake test suite.
560 Now more robust with special characters in file names, or when
561 multiple processes create the same directory at the same time.
563 ** Obsolescent macros
564 The documentation now says that the following macros are obsolescent:
565 they test for problems that are so old that they are no longer of
566 practical importance on current systems.
568 AC_C_BACKSLASH_A AC_FUNC_MEMCMP AC_HEADER_DIRENT
569 AC_C_CONST AC_FUNC_SELECT_ARGTYPES AC_HEADER_STAT
570 AC_C_PROTOTYPES AC_FUNC_SETPGRP AC_HEADER_STDC
571 AC_C_STRINGIZE AC_FUNC_SETVBUF_REVERSED AC_HEADER_SYS_WAIT
572 AC_C_VOLATILE AC_FUNC_STAT AC_HEADER_TIME
573 AC_FUNC_CLOSEDIR_VOID AC_FUNC_STRFTIME AC_ISC_POSIX
574 AC_FUNC_GETPGRP AC_FUNC_UTIME_NULL AC_PROG_GCC_TRADITIONAL
575 AC_FUNC_LSTAT AC_FUNC_VPRINTF AC_STRUCT_TM
577 New programs need not use these macros. We have no current plans to
581 For compatibility with future Libtool 2.0, autoreconf will invoke
582 libtoolize with the option `--ltdl' now, if LT_CONFIG_LTDL_DIR is
585 * Major changes in Autoconf 2.59c
587 Released 2006-04-12, by Ralf Wildenhues.
589 ** The configure command now redirects standard input from /dev/null,
590 to help avoid problems with subsidiary commands that might mistakenly
591 read standard input. AS_ORIGINAL_STDIN_FD points to the original
592 standard input before this redirection, if you really want configure to
593 read from standard input.
595 ** Directory variables adjusted to recent changes in the GNU Coding Standards.
596 The following directory variables are new:
598 datarootdir read-only architecture-independent data root [PREFIX/share]
599 localedir locale-specific message catalogs [DATAROOTDIR/locale]
600 docdir documentation root [DATAROOTDIR/doc/PACKAGE]
601 htmldir html documentation [DOCDIR]
602 dvidir dvi documentation [DOCDIR]
603 pdfdir pdf documentation [DOCDIR]
604 psdir ps documentation [DOCDIR]
606 The following variables have new default values:
608 datadir read-only architecture-independent data [DATAROOTDIR]
609 infodir info documentation [DATAROOTDIR/info]
610 mandir man documentation [DATAROOTDIR/man]
612 This means that if you use any of `@datadir@', `@infodir@', or
613 `@mandir@' in a file, you will have to ensure `${datarootdir}' is
614 defined in this file. As a temporary measure, if any of those are
615 found but no mention of `datarootdir', the substitutions will be
616 replaced with values that do not contain `${datarootdir}', and a
617 warning will be issued.
619 ** @top_builddir@ is now a dir name: it is always nonempty and doesn't have
620 a trailing slash. Similar change will be made to ac_top_builddir in a
621 future release; the old style value, which matches (../)*, is (and will
622 continue to be) available as ac_top_build_prefix.
625 New macro to check for support of 'typeof' syntax a la GNU C.
627 ** AC_CHECK_DECLS_ONCE, AC_CHECK_FUNCS_ONCE, AC_CHECK_HEADERS_ONCE
628 New "once-only" variants of commonly-used macros, to make 'configure'
629 smaller and faster in common cases.
632 New macro to check for strtold with C99 semantics.
635 New macro that lets builder disable assertions at 'configure'-time.
638 Now checks for X11/Xlib.h and XrmInitialize (X proper) rather than
639 X11/Intrinsic.h and XtMalloc (Xt).
641 ** AC_PRESERVE_HELP_ORDER
642 New macro that causes `configure' to display help strings for AC_ARG_ENABLE
643 and AC_ARG_WITH arguments in one region, in the order defined. The default
644 behavior is to group options of each classes separately.
646 ** AC_PROG_CC, AC_PROG_CXX
647 No longer automatically arrange to declare the 'exit' function of C,
648 when a C++ compiler is used. Standard Autoconf macros no longer use
649 'exit', so this is no longer an issue for them. If you use C++, and
650 want to call 'exit', you'll have to arrange for its declaration
651 yourself. But we now suggest you return from 'main' instead.
653 ** AC_PROG_CC_C89, AC_PROG_CC_C99
654 New macros for ISO C99 support. AC_PROG_CC_C89 and AC_PROG_CC_C99
655 check for ANSI C89 and ISO C99 support respectively.
658 Has been unobsoleted, and will check if the compiler supports ISO
659 C99, falling back to ANSI C89 if not. ac_cv_prog_cc_stdc is
660 retained for backwards compatibility, assuming the value of
661 ac_cv_prog_cc_c99 or ac_cv_prog_cc_c89 (whichever is valid, in
664 ** AC_STRUCT_DIRENT_D_INO, AC_STRUCT_DIRENT_D_TYPE
665 New macros for checking commonly-used members of struct dirent.
668 The substituted value can now contain newlines.
671 The substitution now occurs only when @variable@ is on a line by itself,
672 optionally surrounded by spaces and tabs. The whole line is replaced.
674 ** AC_TYPE_LONG_DOUBLE, AC_TYPE_LONG_DOUBLE_WIDER
675 New macros to check for long double, and whether it is wider than double.
676 The old macro AC_C_TYPE_LONG_DOUBLE has been marked as obsolete;
677 applications should switch to the new macro.
679 ** AC_TYPE_INT8_T, AC_TYPE_INT16_T, AC_TYPE_INT32_T, AC_TYPE_INT64_T,
680 AC_TYPE_INTMAX_T, AC_TYPE_INTPTR_T, AC_TYPE_LONG_LONG_INT, AC_TYPE_SSIZE_T,
681 AC_TYPE_UINT8_T, AC_TYPE_UINT16_T, AC_TYPE_UINT32_T, AC_TYPE_UINT64_T,
682 AC_TYPE_UINTMAX_T, AC_TYPE_UINTPTR_T, AC_TYPE_UNSIGNED_LONG_LONG_INT
683 New macros to check for C99 and POSIX types.
685 ** AC_USE_SYSTEM_EXTENSIONS
686 New macro to enable extensions to Posix.
689 New macro which is defined to the name of the first declared config header
690 or undefined if no config headers have been declared yet.
693 The macro correctly handles quadrigraphs now.
695 ** AS_BOURNE_COMPATIBLE, AS_SHELL_SANITIZE, AS_CASE
696 These macros are new or published now.
699 New macro for copyright notices in testsuite files.
701 ** ALLOCA, LIBOBJS, LTLIBOBJS
702 Object names added to these variables are now prefixed with `${LIBOBJDIR}',
703 as in `${LIBOBJDIR}alloca.o'. LIBOBJDIR is meant to be defined from
704 `Makefile.in' in case the object files lie in a different directory.
705 The LIBOBJDIR feature is experimental.
708 Supports --no-recursive now.
710 ** New macros to support Erlang/OTP.
711 New macros for configuring paths to Erlang tools and libraries:
712 AC_ERLANG_PATH_ERLC, AC_ERLANG_NEED_ERLC, AC_ERLANG_PATH_ERL,
713 AC_ERLANG_NEED_ERL, AC_ERLANG_CHECK_LIB, AC_ERLANG_SUBST_ROOT_DIR,
714 AC_ERLANG_SUBST_LIB_DIR.
716 New macros for configuring installation of Erlang libraries:
717 AC_ERLANG_SUBST_INSTALL_LIB_DIR, AC_ERLANG_SUBST_INSTALL_LIB_SUBDIR.
719 ** The manual now mentions Gnulib more prominently.
721 ** New macros to support Objective C.
722 AC_PROG_OBJC, AC_PROG_OBJCPP.
724 * Major changes in Autoconf 2.59b
726 Released 2004-08-20, by Paul Eggert.
729 New macro that computes the default alignment of a type.
731 ** AC_CHECK_TOOL, AC_PATH_TOOL, AC_CHECK_TOOLS
732 When cross-compiling, these macros will give a warning if the tool
733 is not prefixed. In the future, unprefixed cross tools will not
734 be detected; please consult the info documentation for information
735 about the reason of this change.
737 ** AC_CHECK_TARGET_TOOL, AC_PATH_TARGET_TOOL, AC_CHECK_TARGET_TOOLS
738 New macros that detect programs whose name is prefixed with the
739 target type, if the build type and target type are different.
741 ** AC_REQUIRE_AUX_FILE
742 New trace macro that declares expected auxiliary files.
745 New macro that tests for a grep program that accepts as a long a line
748 ** AC_PROG_EGREP, AC_PROG_FGREP
749 These macros now require AC_PROG_GREP, and try EGREP="$GREP -E" and
750 FGREP="$GREP -F" respectively if possible, or else run a path search for
751 a program that accepts as long a line as possible.
754 New macro that tests for a sed program that truncates as few characters
757 * Major changes in Autoconf 2.59
759 Released 2003-11-04, by Akim Demaille
761 ** ac_abs_builddir etc.
762 Absolute file names were actually relative in 2.58.
764 * Major changes in Autoconf 2.58
766 Released 2003-11-04, by Akim Demaille
769 core.* files are no longer removed, as they may be valid user files.
771 ** autoreconf and auxiliary directory
772 Autoreconf creates the auxiliary directory if needed. This is
773 especially useful for initial "bootstrapping" of fresh CVS checkouts.
775 ** AC_CONFIG_MACRO_DIR
776 Use this macro to declare the directory for local M4 macros for aclocal.
779 No longer includes twice the same file in LIBOBJS if invoked
782 ** AC_CONFIG_COMMANDS
783 The directory for its first argument is automatically created. For
786 AC_CONFIG_COMMANDS([src/modules.hh], [...])
788 $top_builddir/src/ is created if needed.
790 ** Autotest and local.at
791 The optional file local.at is always included in Autotest test suites.
794 The warnings are always issued, including with cached runs.
795 This became a significant problem since aclocal and automake can
796 run autoconf behind the scene.
798 ** autoheader warnings
799 The warnings of autoheader can be turned off, using --warning.
800 For instance, -Wno-obsolete disables the complaints about acconfig.h
801 and other deprecated constructs.
804 AC_C_RESTRICT, AC_INCLUDES_DEFAULT, AC_LANG_ASSERT, AC_LANG_WERROR,
807 ** AC_DECL_SYS_SIGLIST
811 Now checks that mktime is the inverse of localtime.
813 ** Improve DJGPP portability
814 The Autoconf tools and configure behave better under DJGPP.
816 ** Present But Cannot Be Compiled
817 New FAQ section dedicated to the mystic
819 configure: WARNING: pi.h: present but cannot be compiled
820 configure: WARNING: pi.h: check for missing prerequisite headers?
821 configure: WARNING: pi.h: proceeding with the preprocessor's result
824 ** Concurrent executions of autom4te
825 autom4te now locks its internal files, which enables concurrent
826 executions of autom4te, likely to happen if automake, autoconf,
827 autoheader etc. are run simultaneously.
830 Use of Libtool 1.5 and higher is encouraged. Compatibility with
831 Libtool pre-1.4 is not checked.
834 Testsuites no longer rerun failed tests in verbose mode; instead,
835 failures are logged while the test is run.
837 In addition, expected failures can be marked as such.
839 * Major changes in Autoconf 2.57
841 Released 2002-12-03 by Paul Eggert.
843 Bug fixes for problems with AIX linker, with freestanding C compilers,
844 with GNU M4 limitations, and with obsolete copies of GNU documents.
846 The Free Documentation License has been upgraded from 1.1 to 1.2.
848 * Major changes in Autoconf 2.56
850 Released 2002-11-15 by Akim Demaille.
852 One packaging problem fixed (config/install-sh was not executable).
854 * Major changes in Autoconf 2.55
856 Released 2002-11-14 by Akim Demaille.
860 Have your configure.ac checked by autoscan ("autoscan").
861 Try the warning options ("autoreconf -fv -Wall").
865 - AC_CHECK_HEADER, AC_CHECK_HEADERS
866 More information on proper use.
868 - Writing Test Programs
870 This sections explains how to write good test sources to use with
871 AC_COMPILE_IFELSE etc. It documents AC_LANG_PROGRAM and so forth.
873 - AC_FOO_IFELSE vs. AC_TRY_FOO
875 Explains why Autoconf moves from AC_TRY_COMPILE etc. to
876 AC_COMPILE_IFELSE and AC_LANG_PROGRAM etc.
880 - Is more robust to different Gettext installations.
882 - Produces messages (when --verbose) to be understood by Emacs'
885 - Supports -W/--warnings.
888 Once the GNU Build System reinstalled, run `./config.status
889 --recheck && ./config.status && make' if possible.
893 - Supports --cache, and --no-cache.
895 - ~/.autom4te.cfg makes it possible to disable the caching mechanism
896 (autom4te.cache). See `Customizing autom4te' in the documentation.
903 Support for the obsoleted options -m, --macrodir, -l, --localdir is
904 dropped in favor of the safer --include/--prepend-include scheme.
909 AC_COMPILER_IFELSE, AC_FUNC_MBRTOWC, AC_HEADER_STDBOOL,
910 AC_LANG_CONFTEST, AC_LANG_SOURCE, AC_LANG_PROGRAM, AC_LANG_CALL,
911 AC_LANG_FUNC_TRY_LINK, AC_MSG_FAILURE, AC_PREPROC_IFELSE.
914 Obsoleted macros are kept for Autoconf backward compatibility, but
915 should be avoided in configure.ac. Running autoupdate is advised.
918 - AC_DEFINE/AC_DEFINE_UNQUOTED
920 We have to stop using the old compatibility scheme --that tried to
921 avoid useless backslashes-- because Libtool 1.4.3 contains a
923 AC_DEFINE([error_t], [int],
924 [Define to a type to use for \`error_t' if it is not
925 otherwise available.])
927 We have to quote the single quotes and backslashes with \. The old
928 compatibility scheme saw that ` was backslashed, and therefore did
929 not quote the single quote... Failure. Hence, Autoconf 2.54 is not
930 compatible with Libtool. Autoconf 2.55 is, but in some cases might
931 produce more \ than wanted.
933 Please, note that in the future the same problem will happen with
934 AC_MSG_*: use `autoreconf -f -Wall'.
938 - Portability of the Autoconf package to Solaris.
940 - Spurious warnings caused by config.status.
941 This bug is benign, but painful: on some systems (typically
942 FreeBSD), warnings such as:
944 config.status: creating Makefile
945 mv: Makefile: set owner/group (was: 1357/0): Operation not permitted
947 could be issued. This is fixed.
950 Simultaneous executions of config.status are possible again.
952 - Precious variables accumulation
954 config.status could stack several copies of the precious variables
958 ** Plans for later versions
962 The compatibility hooks with the old scheme will be completely
963 removed. Please, advice/use `--build', `--host', and `--target'
966 - AC_CHECK_HEADER, AC_CHECK_HEADERS
968 The tests will be stricter, please make sure your invocations are
973 Shell functions will gradually be introduced, probably starting with
974 Autotest. If you know machines which are in use that you suspect
975 *not* to support shell functions, please run the test suite of
976 Autoconf 2.55 on it, and report the results to
977 bug-autoconf@gnu.org.
981 Special characters in AC_MSG_* need not be quoted. Currently,
982 Autoconf has heuristics to decide when a string is escaped, or has
983 to be escaped. This scheme is fragile, and will be removed; the
984 only risk is uglified messages. Please, run `autoreconf -f -Wall'
985 to find occurrences that will be affected.
987 * Major changes in Autoconf 2.54
989 Released 2002-09-13 by Akim Demaille.
993 - autoreconf no longer changes the version of the gettext/po/intl
994 support files. It now adds the files the correspond to the
995 AM_GNU_GETTEXT_VERSION declared in configure.ac.
997 Warning: It now relies on the 'autopoint' program, which is part
998 of GNU gettext 0.11.4 and newer.
1000 Please note that you need to have a GNU gettext version that
1001 corresponds at least to the AM_GNU_GETTEXT_VERSION declared
1002 in configure.ac. You can upgrade to newer GNU gettext versions,
1003 though, without needing to change configure.ac.
1005 - The -I DIR or --include=DIR option now appends DIR to the include path
1006 instead of prepending; this is for consistency with other GNU tools.
1007 The new -B DIR or --prepend-include=DIR option has the old behavior.
1012 Now handles all the gory details about LIBOBJS and LTLIBOBJS.
1013 Please, remove lines such as
1015 # This is necessary so that .o files in LIBOBJS are also
1016 # built via the ANSI2KNR-filtering rules.
1017 LIBOBJS=`echo $LIBOBJS|sed 's/\.o /\$U.o /g;s/\.o$/\$U.o/'`
1019 and read the `AC_LIBOBJ vs LIBOBJS' section. Do not define U in
1020 your Makefiles either.
1022 - AC_CONFIG_LINKS now makes copies if it can't make links.
1024 - AC_FUNC_FNMATCH now tests only for POSIX compatibility, reverting to
1025 Autoconf 2.13 behavior. The new macro AC_FUNC_FNMATCH_GNU also
1026 tests for GNU extensions to fnmatch, and replaces fnmatch if needed.
1028 - AC_FUNC_SETVBUF_REVERSED no longer fails when cross-compiling.
1030 - AC_PROG_CC_STDC is integrated into AC_PROG_CC.
1032 - AC_PROG_F77 default search no longer includes cf77 and cfg77.
1036 AC_C_BACKSLASH_A, AC_CONFIG_LIBOBJ_DIR, AC_GNU_SOURCE,
1037 AC_PROG_EGREP, AC_PROG_FGREP, AC_REPLACE_FNMATCH,
1038 AC_FUNC_FNMATCH_GNU, AC_FUNC_REALLOC, AC_TYPE_MBSTATE_T.
1040 - AC_FUNC_GETLOADAVG
1041 looks for getloadavg.c in the CONFIG_LIBOBJ_DIR.
1044 Now defines HAVE_MALLOC to 0 if `malloc' does not work, and asks
1045 for an AC_LIBOBJ replacement.
1049 - Spurious complaints from `m4_bmatch' about invalid regular
1050 expressions are suppressed.
1052 - Empty top_builddirs are properly handled.
1054 - AC_CHECK_MEMBER works correctly when the member is an aggregate.
1057 Now colon in the optional path arguments are properly handled.
1059 ** Improved portability
1061 - Both Autoconf the package, and the scripts it produces, should run
1062 more reliably with Zsh. Bear in mind it is the default Bourne shell
1065 - Autoconf and the scripts it produces no longer assume the existence of
1066 the obsolescent commands egrep and fgrep.
1070 - Limitations of Make
1074 The GNATS base moved to
1075 http://bugs.gnu.org/cgi-bin/gnatsweb.pl?database=autoconf
1076 (It is no longer available, though.)
1081 Now contains the list of ouput variables and files (AC_SUBST,
1084 * Major changes in Autoconf 2.53
1086 Released 2002-03-08 by Akim Demaille.
1090 Perl 5.005_03 or later is required: autom4te is written in Perl and is
1091 needed by autoconf. autoheader, autoreconf, ifnames, and autoscan are
1097 Argument requirements, output variables, defined macros.
1098 - M4sugar, M4sh, Autotest
1100 - Double quoting macros
1101 AC_TRY_CPP, AC_TRY_COMPILE, AC_TRY_LINK and AC_TRY_RUN.
1103 The Autoconf manual is now distributed under the terms of the GNU FDL.
1104 - Section `Hosts and Cross-Compilation'
1105 Explains the rationale for the 2.5x changes in the cross-compilation
1106 chain, and in the relationships between build, host, and target
1108 Emphasizes that `cross-compilation' == `--host is given'.
1109 If you are working on compilers etc., be sure to read this section.
1110 - Section `AC_LIBOBJ vs. LIBOBJS'
1111 Explains why assigning LIBOBJS directly is now an error.
1112 Details how to update the code.
1117 Now used instead of hard coded line numbers.
1118 This eases the comparison of `configure's, and diminishes the
1119 pressure over control version archives.
1120 Automatic replacement for shells that don't support this feature.
1121 - New output variables
1122 @builddir@, @top_builddir@, @abs_srcdir@, @abs_top_srcdir@, @abs_builddir@,
1127 Autoconf and Autotest modes are provided.
1132 New, used by the Autoconf suite to cache and speed up most processing.
1134 Supported by autom4te, autoconf and autoheader.
1136 Replaces --autoconf-dir and --localdir in autoconf, autoheader,
1137 autoupdate, and autoreconf.
1139 No longer passes --cygnus, --foreign, --gnits, --gnu, --include-deps:
1140 automake options are to be given via AUTOMAKE_OPTIONS.
1142 Runs gettextize and libtoolize when appropriate.
1144 --m4dir is no longer supported.
1146 Now runs only in the specified directories, defaulting to `.',
1147 but understands AC_CONFIG_SUBDIRS for dependent directories.
1148 Before, it used to run on all the `configure.ac' found in the
1150 Independent packages are properly updated.
1154 - The top level $prefix is propagated to the AC_CONFIG_SUBDIRS configures.
1156 Under the user pressure, $? is finally available. Probably a mistake.
1157 - AC_F77_LIBRARY_LDFLAGS now supports the HP/UX f90 compiler.
1158 - Precious variables accumulation
1159 config.status could stack several copies of the precious variables
1161 - AC_PATH_PROG and family.
1162 Works properly when given a literal path.
1164 Somewhere since 2.13, the result had been reversed.
1168 - AC_C_BIGENDIAN supports the cross-compiling case.
1169 - AC_C_BIGENDIAN accepts ACTION-IF-TRUE, ACTION-IF-FALSE, and
1170 ACTION-IF-UNKNOWN arguments. All are facultative, and the default
1171 for ACTION-IF-TRUE is to define WORDS_BIGENDIAN like AC_C_BIGENDIAN
1173 - AC_C_LONG_DOUBLE now succeeds only if `long double' has more range or
1174 precision than `double'.
1179 It now defines the preprocessor symbols PACKAGE_NAME,
1180 PACKAGE_TARNAME, PACKAGE_VERSION, PACKAGE_STRING, and
1184 Admits a fourth optional parameter: the tar name.
1186 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS.
1187 Provide the user with srcdir, ac_srcdir, ac_top_srcdir, ac_builddir,
1188 ac_top_builddir, ac_abs_srcdir, ac_abs_top_srcdir, ac_abs_builddir,
1189 ac_abs_top_builddir.
1191 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS and AC_OUTPUT.
1192 Are much less expensive when using long lists of files.
1195 Works with shell variables, and non alphanumeric names.
1199 - AC_FUNC_STRERROR_R now sets STRERROR_R_CHAR_P, not HAVE_WORKING_STRERROR_R,
1200 because POSIX 1003.1-200x draft 7 says strerror_r returns int, not char *.
1202 - AC_FUNC_STRTOD substitutes POW_LIB.
1207 * Major changes in Autoconf 2.52
1209 Released 2001-07-18 by Akim Demaille.
1214 This feature was present in autoconf 2.50 but was not documented.
1215 For example, `@<:@' is translated to `[' just before output. This
1216 is useful when writing strings that contain unbalanced quotes, or
1217 other hard-to-quote constructs.
1218 - m4_pattern_forbid, m4_pattern_allow
1219 - Tips for upgrading from 2.13.
1220 - Using autoscan to maintain a configure.ac.
1223 - Now include stdint.h.
1224 - sys/types.h and sys/stat.h are guarded.
1225 - strings.h is included if available, and not conflicting with string.h.
1228 - The test suite is more robust and presents less false failures.
1229 - Invocation of GNU M4 now robust to POSIXLY_CORRECT.
1230 - configure accepts --prefix='' again.
1231 - AC_CHECK_LIB works properly when its first argument is not a
1233 - HAVE_INTTYPES_H is defined only if not conflicting with sys/types.h.
1234 - build_, host_, and target_alias are AC_SUBST as in 2.13.
1235 - AC_ARG_VAR properly propagates precious variables inherited from the
1236 environment to ./config.status.
1237 - Using --program-suffix/--program-prefix is portable.
1238 - Failures to detect the default compiler's output extension are less
1240 - `config.status foo' works properly when `foo' depends on variables
1241 set in an AC_CONFIG_THING INIT-CMD.
1242 - autoheader is more robust to broken input.
1243 - Fixed Fortran name-mangling and link tests on a number of systems,
1244 e.g. NetBSD; see AC_F77_DUMMY_MAIN, below.
1247 - AC_CHECK_HEADER and AC_CHECK_HEADERS support a fourth argument to
1248 specify pre-includes. In this case, the headers are compiled with
1249 cc, not merely preprocessed by cpp. Therefore it is the _usability_
1250 of a header which is checked for, not just its availability.
1251 - AC_ARG_VAR refuses to run configure when precious variables have
1253 - Versions of compilers are dumped in the logs.
1254 - AC_CHECK_TYPE recognizes use of `foo_t' as a replacement type.
1257 - AC_PATH_XTRA only adds -ldnet to $LIBS if it's needed to link.
1258 - AC_FUNC_WAIT3 and AC_SYS_RESTARTABLE_SYSCALLS are obsoleted.
1259 - AM_FUNC_ERROR_AT_LINE, AM_FUNC_FNMATCH, AM_FUNC_MKTIME,
1260 AM_FUNC_OBSTACK, and AM_FUNC_STRTOD are now activated.
1261 Be sure to read `Upgrading from Version 2.13' to understand why
1262 running `autoupdate' is needed.
1263 - AC_F77_DUMMY_MAIN, AC_F77_MAIN: new macros to detect whether
1264 a main-like routine is required/possible when linking C/C++ with
1265 Fortran. Users of e.g. AC_F77_WRAPPERS should be aware of these.
1266 - AC_FUNC_GETPGRG behaves better when cross-compiling.
1268 * Major changes in Autoconf 2.51
1269 There was no release of Autoconf 2.51 since some packagers had used
1270 this version number without permission to ship intermediary versions
1271 of 2.50. The version was skipped to avoid confusion.
1273 * Major changes in Autoconf 2.50
1275 Released 2001-05-21 by Akim Demaille.
1277 ** Lots of bug fixes
1278 There have been far too many to enumerate them here. Check out
1279 ChangeLog if you really want to know more.
1281 ** Improved documentation
1282 In particular, portability issues are better covered.
1285 All the standard GNU Makefile targets are supported. The layout has
1286 changed: m4/ holds the M4 extensions Autoconf needs for its
1287 configuration, doc/ contains the documentation, and tests/ contains
1290 ** Man pages are provided
1291 For autoconf, autoreconf, autoupdate, autoheader, autoscan, ifnames,
1292 config.guess, config.sub.
1296 Provides a safe and powerful means to trace the macro uses. This
1297 provide the parsing layer for tools which need to `study'
1301 Specify what category of warnings should be enabled.
1303 - When recursing into subdirectories, try for configure.gnu before
1304 configure to adapt for packages not using autoconf on case-insensitive
1308 More errors are now caught (circular AC_REQUIRE dependencies,
1309 AC_DEFINE in the action part of an AC_CACHE_CHECK, too many pops
1310 etc.). In addition, their location and call stack are given.
1313 autoupdate is much more powerful, and is able to provide the glue code
1314 which might be needed to move from an old macro to its newer
1317 You are strongly encouraged to use it to modernize both your
1318 `configure.in' and your .m4 extension files.
1321 The internal machinery of autoheader has completely changed. As a
1322 result, using `acconfig.h' should be considered to be obsoleted, and
1323 you are encouraged to get rid of it using the AH macros.
1328 ** Fortran 77 compilers
1329 Globally, the support for Fortran 77 is considerably improved.
1331 Support for automatically determining a Fortran 77 compiler's
1332 name-mangling scheme. New CPP macros F77_FUNC and F77_FUNC_ are
1333 provided to wrap C/C++ identifiers, thus making it easier and more
1334 transparent for C/C++ to call Fortran 77 routines, and Fortran 77 to
1335 call C/C++ routines. See the Texinfo documentation for details.
1338 The test suite no longer uses DejaGNU. It should be easy to submit
1339 test cases in this new framework.
1342 - --help, --help=long, -hl
1343 no longer dumps useless items.
1345 lists only specific options.
1346 - --help=recursive, -hr
1347 displays the help of all the embedded packages.
1348 - Remembers environment variables when reconfiguring.
1349 The previous scheme to set envvar before running configure was
1351 what prevented configure from remembering the environment in which
1352 it was run, therefore --recheck was run in an inconsistent
1353 environment. Now, one should run
1355 and then --recheck will work properly. Variables declared with
1356 AC_ARG_VAR are also preserved.
1358 $build defaults to `config.guess`, $host to $build, and then $target
1360 Cross-compilation is a global status of the package, it no longer
1361 depends upon the current language.
1362 Cross compilation is enabled iff the user specified `--host'.
1363 `configure' now fails if it can't run the executables it compiles,
1364 unless cross-compilation is enabled.
1366 The cache file is disabled by default. The new options
1367 `--config-cache', `-C' set the cache to `config.cache'.
1371 Much faster on most architectures.
1372 - concurrent executions
1373 It is safe to use `make -j' with config.status.
1374 - human interface improved
1375 It is possible to invoke
1376 ./config.status foobar
1377 instead of the former form (still valid)
1378 CONFIG_COMMANDS= CONFIG_HEADERS= CONFIG_LINKS= \
1379 CONFIG_FILES=foobar:foo.in:bar.in \
1381 The same holds for configuration headers and links.
1382 You can instantiate unknown files and headers:
1383 ./config.status --header foo.h:foo.h.in --file bar:baz
1384 - has a useful --help
1385 - accepts special file name "-" for stdin/stdout
1390 Specify additional copyright information.
1393 Now expects the identity of the package as argument.
1397 Most macros, if not all, now strictly follow the `one quotation
1398 level' rule. This results in a more predictable expansion.
1401 A sly bug in the AC_REQUIRE machinery, which could produce incorrect
1402 configure scripts, was fixed by Axel Thimm.
1406 Document and ask for the registration of an envvar.
1409 Specifies the file which `configure' should look for when trying to
1410 find the source tree (used to be handled by AC_INIT).
1412 - AC_CONFIG_COMMANDS
1413 To add new actions to config.status. Should be used instead of
1417 Replaces AC_LINK_FILES.
1419 - AC_CONFIG_HEADERS, AC_CONFIG_COMMANDS, AC_CONFIG_SUBDIRS,
1420 AC_CONFIG_LINKS, and AC_CONFIG_FILES
1421 They now obey sh: you should no longer use shell variables as
1422 argument. Instead of
1424 test "$package_foo_enabled" = yes && $my_subdirs="$my_subdirs foo"
1425 AC_CONFIG_SUBDIRS($my_subdirs)
1429 if test "$package_foo_enabled" = yes; then
1430 AC_CONFIG_SUBDIRS(foo)
1434 To format an Autoconf macro's help string so that it looks pretty
1435 when the user executes `configure --help'.
1438 ** Generic Test Macros
1440 The interface of the AC_CHECK families of macros (decl, header,
1441 type, member, func) is now uniform. They support the same set of
1444 - AC_CHECK_DECL, AC_CHECK_DECLS
1445 To check whether a symbol is declared.
1447 - AC_CHECK_SIZEOF, AC_C_CHAR_UNSIGNED.
1448 No longer need a cross-compilation default.
1451 The test it performs is much more robust than previously, and makes
1452 it possible to test builtin types in addition to typedefs.
1453 It is now schizophrenic:
1454 - AC_CHECK_TYPE(TYPE, REPLACEMENT)
1455 remains for backward compatibility, but its use is discouraged.
1456 - AC_CHECK_TYPE(TYPE, IF-FOUND, IF-NOT-FOUND, INCLUDES)
1457 behaves exactly like the other AC_CHECK macros.
1460 Checks whether given types are supported by the system.
1462 - AC_CHECK_MEMBER, AC_CHECK_MEMBERS
1463 Check for given members in aggregates (e.g., pw_gecos in struct
1467 Checks if the compiler supports ISO C, included when needs special
1471 Checking whether the preprocessor indicates missing includes by the
1472 error code. stderr is checked by AC_TRY_CPP only as a fallback.
1475 Takes a language as argument and replaces AC_LANG_C,
1476 AC_LANG_CPLUSPLUS and AC_LANG_FORTRAN77.
1478 - AC_LANG_PUSH, AC_LANG_POP
1479 Are preferred to AC_LANG_SAVE, AC_LANG_RESTORE.
1482 - AC_FUNC_CHOWN, AC_FUNC_MALLOC, AC_FUNC_STRERROR_R,
1483 AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK, AC_FUNC_STAT, AC_FUNC_LSTAT,
1484 AC_FUNC_ERROR_AT_LINE, AC_FUNC_OBSTACK, AC_FUNC_STRTOD, AC_FUNC_FSEEKO.
1488 Sets GETGROUPS_LIBS.
1490 - AC_FUNC_GETLOADAVG
1491 Defines `HAVE_STRUCT_NLIST_N_UN_N_NAME' instead of `NLIST_NAME_UNION'.
1494 Now integrates `AC_DECL_YYTEXT' which is obsoleted.
1497 Arrange for large-file support.
1499 - AC_EXEEXT, AC_OBJEXT
1500 You are no longer expected to use them: their computation is
1501 performed by default.
1503 ** C++ compatibility
1504 Every macro has been revisited in order to support at best CC=c++.
1506 Major changes in Autoconf 2.14:
1507 There was no release of GNU Autoconf 2.14.
1509 Major changes in Autoconf 2.13:
1511 Released 1999-05-01 by Ben Elliston.
1513 * Support for building on Win32 systems where the only available C or
1514 C++ compiler is the Microsoft Visual C++ command line compiler
1515 (`cl'). Additional support for building on Win32 systems which are
1516 using the Cygwin or Mingw32 environments.
1517 * Support for alternative object file and executable file extensions.
1518 On Win32, for example, these are .obj and .exe. These are discovered
1519 using AC_OBJEXT and AC_EXEEXT, which substitute @OBJEXT@ and
1520 @EXEEXT@ in the output, respectively.
1521 * New macros: AC_CACHE_LOAD, AC_CACHE_SAVE, AC_FUNC_SELECT_ARGTYPES,
1522 AC_VALIDATE_CACHED_SYSTEM_TUPLE, AC_SEARCH_LIBS, AC_TRY_LINK_FUNC,
1523 AC_C_STRINGIZE, AC_CHECK_FILE(S), AC_PROG_F77 (and friends).
1524 * AC_DEFINE now has an optional third argument for a description to be
1525 placed in the config header input file (e.g. config.h.in).
1526 * The C++ code fragment compiled for the C++ compiler test had to be
1527 improved to include an explicit return type for main(). This was
1528 causing failures on systems using recent versions of the EGCS C++
1530 * Fixed an important bug in AC_CHECK_TYPE that would cause a configure
1531 script to report that `sometype_t' was present when only `type_t'
1533 * Merge of the FSF version of config.guess and config.sub to modernize
1534 these scripts. Add support for a few new hosts in config.guess.
1535 Incorporate latest versions of install-sh, mkinstalldirs and
1536 texinfo.tex from the FSF.
1537 * autoreconf is capable of running automake if necessary (and
1539 * Support for Fortran 77. See the Texinfo documentation for details.
1540 * Bug fixes and workarounds for quirky bugs in vendor utilities.
1542 Major changes in Autoconf 2.12:
1544 Released 1996-11-26 by David J. MacKenzie
1546 * AC_OUTPUT and AC_CONFIG_HEADER can create output files by
1547 concatenating multiple input files separated by colons, like so:
1548 AC_CONFIG_HEADER(config.h:conf.pre:config.h.in:conf.post)
1549 AC_OUTPUT(Makefile:Makefile.in:Makefile.rules)
1550 The arguments may be shell variables, to compute the lists on the fly.
1551 * AC_LINK_FILES and AC_CONFIG_SUBDIRS may be called multiple times.
1552 * New macro AC_OUTPUT_COMMANDS adds more commands to run in config.status.
1555 Major changes in Autoconf 2.11:
1557 Released November 18th, 1996, by David J. MacKenzie
1559 * AC_PROG_CC and AC_PROG_CXX check whether the compiler works.
1560 They also default CFLAGS/CXXFLAGS to "-g -O2" for gcc, instead of "-g -O".
1561 * AC_REPLACE_FUNCS defines HAVE_foo if the system has the function `foo'.
1562 * AC_CONFIG_HEADER expands shell variables in its argument.
1563 * New macros: AC_FUNC_FNMATCH, AC_FUNC_SETPGRP.
1564 * The "checking..." messages and the source code for test programs that
1565 fail are saved in config.log.
1566 * Another workaround has been added for seds with small command length limits.
1567 * config.sub and config.guess recognize more system types.
1570 Major changes in Autoconf 2.10:
1572 Released May 7th, 1996, by Roland McGrath
1575 * The cache variable names used by `AC_CHECK_LIB(LIB, FUNC, ...)' has
1576 changed: now $ac_cv_lib_LIB_FUNC, previously $ac_cv_lib_LIB.
1578 Major changes in Autoconf 2.9:
1580 Released March 16th, 1996, by Roland McGrath
1584 Major changes in Autoconf 2.8:
1586 Released March 8th, 1996, by Roland McGrath
1590 Major changes in Autoconf 2.7:
1592 Released November 22nd, 1995, by David J. MacKenzie
1596 Major changes in Autoconf 2.6:
1598 Released November 20th, 1995, by David J. MacKenzie
1602 Major changes in Autoconf 2.5:
1604 Released November 17th, 1995, by Roland McGrath
1606 * New configure options --bindir, --libdir, --datadir, etc., with
1607 corresponding output variables.
1608 * New macro: AC_CACHE_CHECK, to make using the cache easier.
1609 * config.log contains the command being run as well as any output from it.
1610 * AC_CHECK_LIB can check for libraries with "." or "/" or "+" in their name.
1611 * AC_PROG_INSTALL doesn't cache a name for install-sh, for sharing caches.
1612 * AC_CHECK_PROG, AC_PATH_PROG, AC_CHECK_PROGS, AC_PATH_PROGS, and
1613 AC_CHECK_TOOL can search a path other than $PATH.
1614 * AC_CHECK_SIZEOF takes an optional size to use when cross-compiling.
1616 Major changes in Autoconf 2.4:
1618 Released June 14th, 1995, by David J. MacKenzie
1620 * Fix a few bugs found by Emacs testers.
1622 Major changes in Autoconf 2.3:
1624 Released March 27th, 1995, by David J. MacKenzie
1626 * Fix the cleanup trap in several ways.
1627 * Handle C compilers that are picky about option placement.
1628 * ifnames gets the version number from the right directory.
1630 Major changes in Autoconf 2.2:
1632 Released March 8th, 1995, by David J. MacKenzie
1634 * The ifnames utility is much faster but requires a "new awk" interpreter.
1635 * AC_CHECK_LIB and AC_HAVE_LIBRARY check and add the new
1636 library before existing libs, not after, in case it uses them.
1637 * New macros: AC_FUNC_GETPGRP, AC_CHECK_TOOL.
1638 * Lots of bug fixes.
1639 * Many additions to the TODO file :-)
1641 Major changes in Autoconf 2.1:
1643 Released November 4th, 1994, by David J. MacKenzie
1646 * More explanations in the manual.
1647 * Fix a spurious failure in the testsuite.
1648 * Clarify some warning messages.
1649 * autoreconf by default only rebuilds configure and config.h.in files
1650 that are older than any of their particular input files; there is a
1651 --force option to use after installing a new version of Autoconf.
1653 Thanks to everybody who's submitted changes and additions to Autoconf!
1654 I've incorporated many of them, and am still considering others for
1655 future releases -- but I didn't want to postpone this release indefinitely.
1657 Caution: don't indiscriminately rebuild configure scripts with
1658 Autoconf version 2. Some configure.in files need minor adjustments to
1659 work with it; the documentation has a chapter on upgrading. A few
1660 configure.in files, including those for GNU Emacs and the GNU C
1661 Library, need major changes because they relied on undocumented
1662 internals of version 1. Future releases of those packages will have
1663 updated configure.in files.
1665 It's best to use GNU M4 1.3 (or later) with Autoconf version 2.
1666 Autoconf now makes heavy use of M4 diversions, which were implemented
1667 inefficiently in GNU M4 releases before 1.3.
1669 Major changes in Autoconf 2.0:
1671 Released October 26th, 1994, by David J. MacKenzie
1673 ** New copyright terms:
1674 * There are no restrictions on distribution or use of configure scripts.
1677 * Autoconf manual is reorganized to make information easier to find
1678 and has several new indexes.
1679 * INSTALL is reorganized and clearer and is now made from Texinfo source.
1682 * autoscan to generate a preliminary configure.in for a package by
1683 scanning its source code for commonly used nonportable functions,
1684 programs, and header files.
1685 * ifnames to list the symbols used in #if and #ifdef directives in a
1687 * autoupdate to update a configure.in to use the version 2 macro names.
1688 * autoreconf to recursively remake configure and configuration header
1689 files in a source tree.
1691 ** Changed utilities:
1692 * autoheader can take pieces of acconfig.h to replace config.h.{top,bot}.
1693 * autoconf and autoheader can look for package-local definition files
1694 in an alternate directory.
1697 * AC_CACHE_VAL to share results of tests between configure runs.
1698 * AC_DEFUN to define macros, automatically AC_PROVIDE them, and ensure
1699 that macros invoked with AC_REQUIRE don't interrupt other macros.
1700 * AC_CONFIG_AUX_DIR, AC_CANONICAL_SYSTEM, AC_CANONICAL_HOST, AC_LINK_FILES to
1701 support deciding unguessable features based on the host and target types.
1702 * AC_CONFIG_SUBDIRS to recursively configure a source tree.
1703 * AC_ARG_PROGRAM to use the options --program-prefix,
1704 --program-suffix, and --program-transform-name to change the names
1705 of programs being installed.
1706 * AC_PREFIX_DEFAULT to change the default installation prefix.
1707 * AC_TRY_COMPILE to compile a test program without linking it.
1708 * AC_CHECK_TYPE to check whether sys/types.h or stdlib.h defines a given type.
1709 * AC_CHECK_LIB to check for a particular function and library.
1710 * AC_MSG_CHECKING and AC_MSG_RESULT to print test results, on a single line,
1711 whether or not the test succeeds. They obsolete AC_CHECKING and AC_VERBOSE.
1712 * AC_SUBST_FILE to insert one file into another.
1713 * AC_FUNC_MEMCMP to check whether memcmp is 8-bit clean.
1714 * AC_FUNC_STRFTIME to find strftime even if it's in -lintl.
1715 * AC_FUNC_GETMNTENT to find getmntent even if it's in -lsun or -lseq.
1716 * AC_HEADER_SYS_WAIT to check whether sys/wait.h is POSIX.1 compatible.
1719 * Many macros renamed systematically, but old names are accepted for
1720 backward compatibility.
1721 * AC_OUTPUT adds the "automatically generated" comment to
1722 non-Makefiles where it finds @configure_input@ in an input file, to
1723 support files with various comment syntaxes.
1724 * AC_OUTPUT does not replace "prefix" and "exec_prefix" in generated
1725 files when they are not enclosed in @ signs.
1726 * AC_OUTPUT allows the optional environment variable CONFIG_STATUS to
1727 override the file name "config.status".
1728 * AC_OUTPUT takes an optional argument for passing variables from
1729 configure to config.status.
1730 * AC_OUTPUT and AC_CONFIG_HEADER allow you to override the input-file names.
1731 * AC_OUTPUT automatically substitutes the values of CFLAGS, CXXFLAGS,
1732 CPPFLAGS, and LDFLAGS from the environment.
1733 * AC_PROG_CC and AC_PROG_CXX now set CFLAGS and CXXFLAGS, respectively.
1734 * AC_PROG_INSTALL looks for install-sh or install.sh in the directory
1735 specified by AC_CONFIG_AUXDIR, or srcdir or srcdir/.. or
1736 srcdir/../.. by default.
1737 * AC_DEFINE, AC_DEFINE_UNQUOTED, and AC_SUBST are more robust and smaller.
1738 * AC_DEFINE no longer prints anything, because of the new result reporting
1739 mechanism (AC_MSG_CHECKING and AC_MSG_RESULT).
1740 * AC_VERBOSE pays attention to --quiet/--silent, not --verbose.
1741 * AC_ARG_ENABLE and AC_ARG_WITH support whitespace in the arguments to
1742 --enable- and --with- options.
1743 * AC_CHECK_FUNCS and AC_CHECK_HEADERS take optional shell commands to
1744 execute on success or failure.
1745 * Checking for C functions in C++ works.
1748 * AC_REMOTE_TAPE and AC_RSH removed; too specific to tar and cpio, and
1749 better maintained with them.
1750 * AC_ARG_ARRAY removed because no one was likely using it.
1751 * AC_HAVE_POUNDBANG replaced with AC_SYS_INTERPRETER, which doesn't
1752 take arguments, for consistency with all of the other specific checks.
1755 * Comes with config.sub and config.guess, and uses them optionally.
1756 * Uses config.cache to cache test results. An alternate cache file
1757 can be selected with the --cache-file=FILE option.
1758 * Uses optional shell scripts $prefix/share/config.site and
1759 $prefix/etc/config.site to perform site or system specific initializations.
1760 * configure saves compiler output to ./config.log for debugging.
1761 * New files autoconf.m4 and autoheader.m4 load the other Autoconf macros.
1762 * acsite.m4 is the new name for the system-wide aclocal.m4.
1763 * Has a DejaGnu test suite.
1765 Major changes in Autoconf 1.11:
1767 * AC_PROG_INSTALL calls install.sh with the -c option.
1768 * AC_SET_MAKE cleans up after itself.
1769 * AC_OUTPUT sets prefix and exec_prefix if they weren't set already.
1770 * AC_OUTPUT prevents shells from looking in PATH for config.status.
1772 Plus a few other bug fixes.
1774 Major changes in Autoconf 1.10:
1776 * autoheader uses config.h.bot if present, analogous to config.h.top.
1777 * AC_PROG_INSTALL looks for install.sh in srcdir or srcdir/.. and
1779 * AC_PROG_CXX looks for cxx as a C++ compiler.
1781 Plus several bugs fixed.
1783 Major changes in Autoconf 1.9:
1785 * AC_YYTEXT_POINTER replaces AC_DECLARE_YYTEXT.
1786 * AC_SIZEOF_TYPE generates the cpp symbol name automatically,
1787 and autoheader generates entries for those names automatically.
1788 * AC_FIND_X gets the result from xmkmf correctly.
1789 * AC_FIND_X assumes no X if --without-x was given.
1790 * AC_FIND_XTRA adds libraries to the variable X_EXTRA_LIBS.
1791 * AC_PROG_INSTALL finds OSF/1 installbsd.
1793 Major changes in Autoconf 1.8:
1796 * New macros AC_LANG_C, AC_LANG_CPLUSPLUS, AC_LANG_SAVE, AC_LANG_RESTORE,
1797 AC_PROG_CXX, AC_PROG_CXXCPP, AC_REQUIRE_CPP
1798 for checking both C++ and C features in one configure script.
1799 * New macros AC_CHECKING, AC_VERBOSE, AC_WARN, AC_ERROR for printing messages.
1800 * New macros AC_FIND_XTRA, AC_MMAP, AC_SIZEOF_TYPE, AC_PREREQ,
1801 AC_SET_MAKE, AC_ENABLE.
1804 * AC_FIND_X looks for X in more places.
1805 * AC_PROG_INSTALL defaults to install.sh instead of cp, if it's in srcdir.
1806 install.sh is distributed with Autoconf.
1807 * AC_DECLARE_YYTEXT has been removed because it can't work, pending
1808 a rewrite of quoting in AC_DEFINE.
1809 * AC_OUTPUT adds its comments in C format when substituting in C files.
1810 * AC_COMPILE_CHECK protects its ECHO-TEXT argument with double quotes.
1812 ** New or changed command line options:
1813 * configure accepts --enable-FEATURE[=ARG] and --disable-FEATURE options.
1814 * configure accepts --without-PACKAGE, which sets withval=no.
1815 * configure accepts --x-includes=DIR and --x-libraries=DIR.
1816 * Giving --with-PACKAGE no argument sets withval=yes instead of withval=1.
1817 * configure accepts --help, --version, --silent/--quiet, --no-create options.
1818 * configure accepts and ignores most other Cygnus configure options, and
1819 warns about unknown options.
1820 * config.status accepts --help, --version options.
1822 ** File names and other changes:
1823 * Relative srcdir values are not made absolute.
1824 * The values of @prefix@ and @exec_prefix@ and @top_srcdir@ get substituted.
1825 * Autoconf library files are installed in ${datadir}/autoconf, not ${datadir}.
1826 * autoheader optionally copies config.h.top to the beginning of config.h.in.
1827 * The example Makefile dependencies for configure et al. work better.
1828 * Namespace cleanup: all shell variables used internally by Autoconf
1829 have names beginning with `ac_'.
1831 More big improvements are in process for future releases, but have not
1832 yet been (variously) finished, integrated, tested, or documented enough
1835 Major changes in Autoconf 1.7:
1837 * New macro AC_OBSOLETE.
1838 * Bugs in Makefile.in fixed.
1839 * AC_LONG_FILE_NAMES improved.
1841 Major changes in Autoconf 1.6:
1843 * New macro AC_LONG_64_BITS.
1844 * Multiple .h files can be created.
1845 * AC_FIND_X looks for X files directly if it doesn't find xmkmf.
1846 * AC_ALLOCA defines C_ALLOCA if using alloca.c.
1847 * --with-NAME can take a value, e.g., --with-targets=sun4,hp300bsd.
1848 * Unused --no-create option to configure removed.
1849 * autoheader doesn't change the timestamp of its output file if
1850 the file didn't change.
1851 * All macros that look for libraries now use AC_HAVE_LIBRARY.
1852 * config.status checks three optional environment variables to
1853 modify its behavior.
1854 * The usual bug fixes.
1856 Major changes in Autoconf 1.5:
1858 * New macros AC_FIND_X, AC_OFF_T, AC_STAT_MACROS_BROKEN, AC_REVISION.
1859 * autoconf and autoheader scripts have GNU standards conforming
1860 --version and --help options (they print their message and exit).
1863 Major changes in Autoconf 1.4:
1865 * New macros AC_HAVE_POUNDBANG, AC_TIME_WITH_SYS_TIME, AC_LONG_DOUBLE,
1866 AC_GETGROUPS_T, AC_DEFINE_UNQUOTED.
1867 * autoconf and autoheader use the M4 environment variable to determine the
1868 name of the M4 program to use.
1869 * The --macrodir option to autoconf and autoheader specifies the directory
1870 in which acspecific.m4, acgeneral.m4, etc. reside if not the default.
1871 * autoconf and autoheader can take `-' as their file names, which means to
1872 read stdin as input.
1873 * Resulting configure scripts can take a --verbose option which causes them
1874 to print the results of their tests.
1875 * AC_DEFINE quotes its second argument in such a way that spaces, magic
1876 shell characters, etc. will be preserved during various stages of
1877 expansion done by the shell. If you don't want this, use
1878 AC_DEFINE_UNQUOTED instead.
1879 * Much textual processing done with external calls to tr and sed have been
1880 internalized with builtin M4 `patsubst' and `translit' calls.
1881 * AC_OUTPUT doesn't hardwire the file names it outputs. Instead, you can
1882 set the shell variables `gen_files' and `gen_config' to the list of
1883 file names to output.
1884 * AC_DECLARE_YYTEXT does an AC_SUBST of `LEX_OUTPUT_ROOT', which may be
1885 "lex.yy" or "lexyy", depending on the system.
1886 * AC_PROGRAMS_CHECK takes an optional third arg. If given, it is used as
1888 * If AC_ALLOCA chooses alloca.c, it also defines STACK_DIRECTION.
1889 * AC_CONST works much more reliably on more systems.
1892 Major changes in Autoconf 1.3:
1894 configure no longer requires awk for packages that use a config.h.
1895 Support handling --with-PACKAGE options.
1896 New `autoheader' script to create `config.h.in' from `configure.in'.
1897 Ignore troublesome -lucb and -lPW when searching for alloca.
1898 Rename --exec_prefix to --exec-prefix for GNU standards conformance.
1899 Improve detection of STDC library.
1900 Add AC_HAVE_LIBRARY to check for non-default libraries.
1901 Function checking should work with future GNU libc releases.
1903 Major changes in Autoconf 1.2:
1905 The --srcdir option is now usually unnecessary.
1906 Add a file containing sample comments describing CPP macros.
1907 A comment in config.status tells which host it was configured on.
1908 Substituted variable values can now contain commas.
1909 Fix bugs in various feature checks.
1911 Major changes in Autoconf 1.1:
1913 Added AC_STRCOLL macro.
1914 Made AC_GETLOADAVG check for more things.
1915 AC_OUTPUT argument is now optional.
1920 Copyright (C) 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002,
1921 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
1923 Copying and distribution of this file, with or without modification,
1924 are permitted in any medium without royalty provided the copyright
1925 notice and this notice are preserved. This file is offered as-is,
1926 without warranty of any kind.