1 GNU Autoconf NEWS - User visible changes.
3 * Major changes in Autoconf 2.64 (2009-??-??) [stable]
4 Released by Eric Blake, based on git versions 2.63b.*.
6 ** AS_IF and AS_CASE have been taught to avoid syntax errors even when
7 given arguments that expand to just whitespace.
9 ** The following documented autoconf macros are new:
10 AC_ERLANG_SUBST_ERTS_VER
12 ** Ensure AT_CHECK can support commands that include a # given with
13 proper m4 quoting. For shell comments, this is a new feature; for
14 non-shell comments, this fixes a regression introduced in 2.63b.
15 Additionally, AT_CHECK correctly supplies shell escapes for
16 metacharacters occurring in m4 macro expansions within the expected
17 stdout and stderr parameters.
19 ** The macro AT_CHECK now understands the concept of hard failure. If
20 a test exits with an unexpected status 99, cleanup actions for the
21 test are inhibited and the test is treated as a failure regardless
22 of AT_XFAIL_IF. It also understands the new directives
23 ignore-nolog, stdout-nolog, and stderr-nolog.
25 ** The following documented autotest macros are new:
28 ** The following documented m4sugar macros are new:
29 m4_argn m4_copy_force m4_default_nblank m4_default_nblank_quoted
30 m4_ifblank m4_ifnblank m4_rename_force
32 * Major changes in Autoconf 2.63b (2009-03-31) [beta]
33 Released by Eric Blake, based on git versions 2.63.*.
35 ** The manual is now shipped under the terms of the GNU FDL 1.3.
37 ** AC_REQUIRE now detects the case of an outer macro which first expands
38 then later indirectly requires the same inner macro. Previously,
39 this case led to silent out-of-order expansion (bug present since
40 2.50); it now issues a syntax warning, and duplicates the expansion
41 of the inner macro to guarantee dependencies have been met. See
42 the manual for advice on how to refactor macros in order to avoid
43 the bug in earlier autoconf versions and avoid increased script
44 size in the current version.
46 ** AC_DEFUN_ONCE has improved semantics. Previously, a macro declared
47 with AC_DEFUN_ONCE warned on a second invocation; and out-of-order
48 expansion was still possible. Now, dependencies are guaranteed,
49 and subsequent invocations are a silent no-op. This makes
50 AC_DEFUN_ONCE an ideal macro for silencing AC_REQUIRE warnings.
52 ** The following macros are now defined with AC_DEFUN_ONCE. This means
53 a subtle change in semantics; previously, an AC_DEFUN macro could
54 expand one of these macros multiple times or surround the macro
55 inside shell conditional text to bypass the effects of these
56 macros, but now the macro will expand exactly once, and prior to
57 the start of any enclosing AC_DEFUN macro:
58 AC_CANONICAL_BUILD AC_CANONICAL_HOST AC_CANONICAL_TARGET
59 AC_HEADER_ASSERT AC_PROG_INSTALL AC_PROG_MKDIR_P
60 AC_USE_SYSTEM_EXTENSIONS
62 ** AC_LANG_ERLANG works once again (regression introduced in 2.61a).
64 ** AC_HEADER_ASSERT is fixed so that './configure --enable-assert' no
65 longer mistakenly disables assertions.
67 ** AC_INIT now takes an optional fifth parameter that can be used to
68 set AC_PACKAGE_URL, a URL for the package's home page; the URL is
69 used in `configure --help' and is also available via AC_DEFINE.
71 ** Autotest testsuites accept an option --jobs[=N] for parallel testing.
72 This feature is still in testing, and may not work on every
73 platform, help in improving it would be appreciated.
75 ** Autotest testsuites do not attempt to write startup error messages
76 to the log file before that is opened (regression introduced in 2.63).
78 ** Configure scripts now use shell functions. This feature leads to
79 smaller configure files and faster execution.
81 ** Present But Cannot Be Compiled: Autoconf will now proceed with
82 the compiler's result if a header is present but cannot be compiled.
83 The warning is still printed, and you should really fix it by
84 providing a fourth parameter to AC_CHECK_HEADER/AC_CHECK_HEADERS.
86 ** Autoreconf added aclocal to the set of programs affected by the
87 `autoreconf -I dir' option.
89 ** The following documented m4sugar macros are new:
90 m4_chomp m4_chomp_all m4_cleardivert m4_curry m4_default_quoted
91 m4_esyscmd_s m4_map_args m4_map_args_pair m4_map_args_sep
92 m4_map_args_w m4_set_map m4_set_map_sep m4_stack_foreach
93 m4_stack_foreach_lifo m4_stack_foreach_sep
94 m4_stack_foreach_sep_lifo
96 ** The following m4sugar macros are documented now, but in some cases
97 with slightly different semantics than what the previous
98 undocumented version had:
99 m4_copy m4_dumpdefs m4_rename m4_version_prereq
101 ** The m4sugar macro m4_expand has been taught to handle unterminated
102 comments and shell case statements. As a result, it is used
103 internally in more places, such as AC_DEFINE and AT_CHECK. Most
104 uses of AC_DEFINE and AT_CHECK should not behave any differently;
105 however, it may be necessary to add double-quoting around
106 unbalanced `(' where single-quoting used to be sufficient.
108 ** The following documented m4sh macros are new:
109 AS_INIT_GENERATED AS_LINENO_PREPARE AS_ME_PREPARE AS_SET_STATUS
110 AS_VAR_APPEND AS_VAR_ARITH AS_VAR_COPY
112 ** The following m4sh macros are documented now, but in some cases
113 with slightly different semantics than what the previous
114 undocumented version had:
115 AS_ECHO AS_ECHO_N AS_ESCAPE AS_EXIT AS_LITERAL_IF AS_UNSET
116 AS_VAR_IF AS_VAR_POPDEF AS_VAR_PUSHDEF AS_VAR_SET AS_VAR_SET_IF
117 AS_VAR_TEST_SET AS_VERSION_COMPARE
119 ** The m4sh macros AS_IF and AS_CASE can now be used in shell lists.
120 The responsibility for supplying a trailing newline now belongs to
121 the call site, but since most users did not add dnl, this generally
122 results in fewer empty lines in configure.
125 * Major changes in Autoconf 2.63 (2008-09-09) [stable]
126 Released by Eric Blake, based on git versions 2.62.*.
128 ** AC_C_BIGENDIAN does not mistakenly report "universal" for some
129 bigendian hosts, a regression introduced with universal binary
132 ** AC_PATH_X now includes /lib64 and /usr/lib64 in its list of default
135 ** AC_USE_SYSTEM_EXTENSIONS no longer conflicts with an external
136 AC_DEFINE([__EXTENSIONS__]). This fixes a regression introduced in
137 2.62 when using macros such as AC_AIX that were made obsolete in
138 favor of the more portable AC_USE_SYSTEM_EXTENSIONS.
140 ** AC_CHECK_TARGET_TOOLS is usable in the non-cross-compile case.
142 ** Newly obsolete macros
143 The following macro has been marked obsolete, since current porting
144 targets can safely assume C89 semantics that signal handlers return
145 void. We have no current plans to remove the macro.
149 ** The macros m4_map and m4_map_sep now ignore any list elements
150 consisting of just empty quotes, and m4_map_sep now expands its
151 separator. This fixes a regression in 2.62 when these macros were
152 first documented, for the sake of clients expecting the semantics
153 that these macros had prior to that time. The new macros m4_mapall
154 and m4_mapall_sep, along with extra quoting of the separator, can
155 be used to get the semantics that m4_map_sep had in 2.62.
157 ** Clients of m4_expand, such as AS_HELP_STRING and AT_SETUP, can now
158 handle properly quoted but otherwise unbalanced parentheses (for
159 some macros, this fixes a regression in 2.62).
161 ** Two new quadrigraphs have been introduced: @{:@ for (, and @:}@ for ),
162 allowing the output of unbalanced parentheses in more contexts.
164 ** The following m4sugar macros are new:
165 m4_cleardivert m4_joinall m4_mapall m4_mapall_sep m4_reverse
166 m4_set_add m4_set_add_all m4_set_contains m4_set_contents
167 m4_set_delete m4_set_difference m4_set_dump m4_set_empty
168 m4_set_foreach m4_set_intersection m4_set_list m4_set_listc
169 m4_set_remove m4_set_size m4_set_union
171 ** The following m4sugar macros now accept multiple arguments, as is the
172 case with underlying m4:
173 m4_defn m4_popdef m4_undefine
175 ** The following m4sugar macros now guarantee linear scaling; they
176 previously had linear scaling with m4 1.6 but quadratic scaling
177 when using m4 1.4.x. All macros built on top of these also gain
178 the scaling improvements.
179 m4_bmatch m4_bpatsubsts m4_case m4_cond m4_do m4_dquote_elt
180 m4_foreach m4_join m4_list_cmp m4_map m4_map_sep m4_max
183 ** AT_KEYWORDS once again performs expansion on its argument, such that
184 AT_KEYWORDS([m4_if([$1], [], [default])]) no longer complains about
185 the possibly unexpanded m4_if [regression introduced in 2.62].
187 ** Config header templates `#undef UNDEFINED /* comment */' do not lead to
188 nested comments any more; regression introduced in 2.62.
191 * Major changes in Autoconf 2.62 (2008-04-05) [stable]
192 Released by Eric Blake, based on git versions 2.61a.*.
194 ** Many optimizations have been applied to make overall execution faster.
196 ** Autotest now makes use of shell functions.
198 ** config.status now uses awk instead of sed also for config headers.
200 - As a side effect, AC_DEFINE and AC_DEFINE_UNQUOTED now handle multi-line
201 values, i.e., backslash-newline combinations are handled correctly.
202 Further, for config headers, the total size of values is not limited by
203 the POSIX length limit of text lines any more, only each single line.
205 ** New config variable `top_build_prefix'.
207 ** New Autoconf macros:
208 AC_AUTOCONF_VERSION AC_OPENMP AC_PATH_PROGS_FEATURE_CHECK
210 ** AC_C_BIGENDIAN now supports universal binaries a la Mac OS X.
212 ** AC_C_RESTRICT now prefers to #define 'restrict' to a variant spelling
213 like '__restrict' if the variant spelling is available, as this is
214 more likely to work when mixing C and C++ code.
216 ** AC_CHECK_ALIGNOF's type argument T is now documented better: it must
217 be a string of tokens such that "T y;" is a valid member declaration
220 ** AC_CHECK_SIZEOF now accepts objects as well as types: the general rule
221 is that sizeof (X) works, then AC_CHECK_SIZEOF (X) should work.
223 ** AC_CHECK_TYPE and AC_CHECK_TYPES now work on any C type-name; formerly,
224 they did not work for function types. In C++, they now work on any
225 type-id that can be the operand of sizeof; this is similar to C,
226 except it excludes anonymous struct and union types. Formerly,
227 some (but not all) C++ types involving anonymous struct and union
228 were accepted, though this was not documented.
230 ** AC_CONFIG_LINKS now prefers to link against files in the build tree
231 if found, and it works to link against a file of the same name in
232 the source tree, even if both trees coincide.
234 ** AC_INIT no longer alters $@; regression introduced in 2.60.
236 ** AC_USE_SYSTEM_EXTENSIONS now defines _ALL_SOURCE for Interix platforms.
238 ** AS_HELP_STRING no longer underquotes its first argument; it also handles
239 the case where the first argument contains single-quoted commas.
240 For example, "AS_HELP_STRING([-a, [--arg[=foo]]], [bar])" produces:
241 " -a, --arg[=foo] bar"
242 Additionally, the macro now takes two additional arguments,
243 indent-column and wrap-column; these should not normally be needed,
244 but can be used to fine-tune how the output text is wrapped.
246 ** AC_PROG_INSTALL now requires an install program that can install multiple
247 files into a target directory.
249 ** The command 'autoconf -' now correctly processes a file from stdin.
251 ** 'autoreconf -m' now honors $MAKE.
253 ** For all of the directory arguments for 'configure', such as '--prefix'
254 or '--bindir', trailing slashes are stripped. As an example, if
255 tab completion in the user's shell appends trailing slashes, the
256 command './configure --prefix=/usr/' will still result in an
257 expanded libdir value of /usr/lib, not /usr//lib.
259 ** `configure --help=recursive' now works in read-only trees and from
260 unconfigured build trees.
262 ** If precious variables differ only in whitespace, then the cache consistency
263 check warns instead of fails, and reuses the old value.
265 ** AT_BANNER is now documented.
267 ** AT_SETUP now handles macro expansions properly when calculating line
270 ** Autotest now determines $srcdir correctly.
272 ** Testsuites built by autotest now accept a -C/--directory=DIR option
273 to adjust the working directory prior to creating files.
275 ** Autoconf now requires GNU M4 1.4.5 or later. Earlier versions of M4 have
276 a bug in macro tracing that interferes with the interaction between
277 Autoconf and Automake. GNU M4 1.4.11 or later is recommended. The
278 configure search for a working M4 is improved.
280 ** For portability with the eventual M4 2.0, macros should no longer use
281 anything larger than $9 to refer to arguments.
283 ** Documentation for m4sugar is improved.
285 - The following macros were previously available as undocumented
286 interfaces; the macros are now documented as stable interfaces.
288 __oline__ m4_assert m4_bmatch m4_bpatsubsts m4_car m4_case
289 m4_cdr m4_default m4_divert_once m4_divert_pop m4_divert_push
290 m4_divert_text m4_do m4_errprintn m4_fatal m4_flatten
291 m4_ifndef m4_ifset m4_ifval m4_ifvaln m4_location
292 m4_n m4_shiftn m4_strip m4_warn
294 - The following macros were previously available as undocumented
295 interfaces, but had bug fixes or semantic changes as part of this
296 release. Packages that relied on the undocumented behavior
297 should be analyzed to make sure they will still work with the
298 new documented behavior.
300 m4_cmp m4_list_cmp m4_join m4_map m4_map_sep m4_sign
301 m4_text_box m4_text_wrap m4_version_compare
303 - The m4_wrap macro used to have unspecified order, but now
304 guarantees FIFO order. m4_wrap_lifo was added to guarantee LIFO
307 - Packages using the undocumented m4sugar macro m4_PACKAGE_VERSION
308 should consider using the new AC_AUTOCONF_VERSION instead.
310 - m4sugar macros that are not documented in the manual are still
311 deemed experimental, and should not be used outside of Autoconf.
313 ** The m4sugar macros m4_append and m4_append_uniq, first documented in
314 2.60, have been fixed to treat both the string and the separator
315 arguments consistently with regards to quoting. Prior to this fix,
316 m4_append_uniq could mistakenly duplicate entries if the expansion
317 of the separator resulted in a different string (for example, if it
318 contained quotes, a comma, or a macro name). However, it means
319 that programs previously using
320 m4_append([name], [string], [[, ]])
321 are now using a four-character separator instead of the intended
322 comma and space. If you need portability to earlier versions of
323 Autoconf, you can insert the following snippet after AC_INIT but
324 before any other macro expansions, to enforce the new semantics:
325 m4_pushdef([m4_append], [m4_define([$1],
326 m4_ifdef([$1], [m4_defn([$1])[$3]])[$2])])
327 Additionally, m4_append_uniq now takes optional parameters that can
328 be used to take action depending on whether anything was appended,
329 and warns if a non-empty separator occurs within the string being
330 appended, since that can lead to duplicates.
332 ** The following m4sugar macros are new:
333 m4_append_uniq_w m4_apply m4_combine m4_cond m4_count
334 m4_dquote_elt m4_echo m4_expand m4_ignore m4_make_list m4_max
335 m4_min m4_newline m4_shift2 m4_shift3 m4_unquote m4_wrap_lifo
337 ** Warnings are now generated by default when an installer invokes
338 'configure' with an unknown --enable-* or --with-* option.
339 These warnings can be disabled with the new AC_DISABLE_OPTION_CHECKING
340 macro, or by invoking 'configure' with --disable-option-checking.
342 ** Existing obsolete macros
343 The documentation for the following macros is adjusted to make it
344 more clear that they have previously been marked obsolete, as their
345 functionality can be accomplished by other macros. We have no
346 current plans to remove them from Autoconf.
348 AC_ENABLE AC_STRUCT_ST_BLKSIZE AC_STRUCT_ST_RDEV AC_WITH
350 ** Newly obsolete macros
351 The following macros have been marked obsolete, as they only
352 perform a subset of AC_USE_SYSTEM_EXTENSIONS. We have no current
353 plans to remove them.
355 AC_AIX AC_GNU_SOURCE AC_ISC_POSIX AC_MINIX
357 ** AC_C_LONG_DOUBLE is obsolescent.
358 The documentation now says that AC_C_LONG_DOUBLE is obsolescent: it
359 tests for problems that are so old that it is no longer of
360 practical importance on current systems. New programs need not use
361 AC_C_LONG_DOUBLE. We have no current plans to remove it.
363 ** AC_DIAGNOSE, AC_WARNING, and AC_FATAL are obsolescent.
364 The documentation now favors the use of M4sugar macros m4_warn and
365 m4_fatal, since the naming makes it more obvious that the
366 diagnostics are associated with M4 expansion (ie. when running
367 `autoconf'), and offers less confusion with the AC_MSG_ERROR,
368 AC_MSG_FAILURE, and AC_MSG_WARN macros which manage diagnostics
369 when running `configure'. We have no current plans to remove these
373 * Major changes in Autoconf 2.61a (2006-12-11)
375 ** AC_FUNC_FSEEKO was broken in 2.61; it didn't make fseeko and ftello visible
376 on many platforms. This has been fixed.
378 ** AC_FUNC_SETVBUF_REVERSED is now obsolete. It is still defined for backward
379 compatibility but it does nothing. The macro was already
380 obsolescent, as the last systems to have the problem were those
381 based on SVR2, which became obsolete in 1987. The macro had bugs
382 on some modern systems and could no longer be maintained reliably
383 due to lack of ancient systems to test it on.
385 ** config.status now uses awk instead of sed for most substitutions, for speed.
387 - As a side effect multi-line values of substituted variables no
388 longer have a small limit in total size, though for portability
389 each line should not exceed the POSIX length limit for text lines.
391 - It is now documented that Makefile.in should not contain
392 overlapping variable occurrences, e.g., @VAR1@VAR2@.
393 Autoconf's behavior was always iffy in such cases, and the
394 awk implementation has changed the behavior.
396 ** Many uses of 'echo' have been rewritten so that Autoconf-generated
397 scripts have fewer problems with strings or file names containing
398 embedded special characters such as backslash or leading "-". This
399 was implemented by using `printf '%s\n' "$foo"' instead of `echo
400 "$foo"' when printf works. Due to the implementation technique
401 used, Autoconf-generated scripts now run considerably more slowly
402 on ancient implementations lacking printf. However, this should
403 not be a problem, since Autoconf-generated scripts in practice
404 invariably find a more-modern shell these days.
407 * Major changes in Autoconf 2.61 (2006-11-17)
409 ** New macros AC_C_FLEXIBLE_ARRAY_MEMBER, AC_C_VARARRAYS.
411 ** AC_ARG_ENABLE and AC_ARG_WITH now allow '.' in feature and package names.
414 * Major changes in Autoconf 2.60b (2006-10-22)
417 Autoconf-generated shell scripts no longer export BIN_SH, due to
418 configuration hassles with this. Installers who need BIN_SH in
419 their environment should set it before invoking 'configure' and
420 'make'. As far as we know, this affects only Unixware installations.
422 ** Obsolescent macros
423 The documentation now says that the following macros are obsolescent,
424 as they are superseded by Gnulib:
426 AC_FUNC_FNMATCH AC_FUNC_FNMATCH_GNU AC_FUNC_GETLOADVG AC_REPLACE_FNMATCH
428 New programs should use the Gnulib counterparts of these macros.
429 We have no current plans to remove them from Autoconf.
431 ** AC_COMPUTE_INT no longer caches or reports results.
433 ** AC_CHECK_DECL now also works with aggregate objects.
435 ** AC_USE_SYSTEM_EXTENSIONS now defines _TANDEM_SOURCE for NonStop platforms.
437 ** GNU M4 1.4.7 or later is now recommended.
440 New M4sugar macro, which is more secure than the POSIX M4 maketemp.
443 Now an alias for m4_mkstemp.
445 * Major changes in Autoconf 2.60a (2006-08-25)
447 ** GNU M4 1.4.6 or later is now recommended.
449 ** The check for C99 now tests for varargs macros, as documented.
450 It also tests that the preprocessor supports 64-bit integers.
452 ** Autoconf now uses constructs like "#ifdef HAVE_STDLIB_H" rather than
453 "#if HAVE_STDLIB_H", so that it now works with "gcc -Wundef -Werror".
455 ** The functionality of the undocumented _AC_COMPUTE_INT is now provided
456 by a public and documented macro, AC_COMPUTE_INT. The parameters to the
457 two macros are different, so autoupdate will not change the old private name
458 to the new one. _AC_COMPUTE_INT may be removed in a future release.
460 ** AC_TYPE_LONG_LONG_INT and AC_TYPE_UNSIGNED_LONG_LONG_INT now require
461 that long long types be at least 64 bits wide, as C99 and tradition
462 requires. Formerly, they accepted implementations of any width.
465 * Major changes in Autoconf 2.60
467 Released 2006-06-23, by Ralf Wildenhues.
469 ** Autoconf no longer depends on whether m4wrap is FIFO (as Posix requires)
470 or LIFO (as in GNU M4 1.4.x). GNU M4 2.0 is expected to conform to Posix
471 here, so m4wrap/m4_wrap users should no longer depend on LIFO behavior.
473 ** Provide a way to turn off warnings about the changed directory variables.
475 * Major changes in Autoconf 2.59d
477 Released 2006-06-05, by Ralf Wildenhues.
479 ** GNU make now recommended for VPATH builds
480 INSTALL now suggests VPATH builds (e.g., "sh ../srcdir/configure")
481 only if you use GNU make. In practice, other 'make' implementations
482 have too many subtle incompatibilities in their support for VPATH.
483 Many packages (including Autoconf itself) are portable to other
484 'make' implementations, but some packages are not, and recommending
485 GNU make keeps the installation instructions simpler.
487 ** Even more safety checks for the new Directory variables:
488 Warn about suspicious `${datarootdir}' found in config files output.
490 ** AC_TRY_COMMAND, AC_TRY_EVAL, ac_config_guess, ac_config_sub, ac_configure
491 These never-documented macros and variables have been marked with
492 comments saying that they may be removed in a future release,
493 because their use can lead to unintended code being executed.
494 If you need functionality that only these macros or variables
495 currently supply, please write bug-autoconf@gnu.org.
497 ** AC_SUBST, AC_DEFINE
498 Literal arguments to these are passed to m4_pattern_allow now.
501 Passing 'ac_cv_prog_cc_stdc=no' to 'configure' now sets ac_cv_prog_cc_c99
502 and ac_cv_prog_cc_c89 to 'no' as well, for backward compatibility with
503 obsolete K&R tests in the Automake test suite.
512 Now more robust with special characters in file names, or when
513 multiple processes create the same directory at the same time.
515 ** Obsolescent macros
516 The documentation now says that the following macros are obsolescent:
517 they test for problems that are so old that they are no longer of
518 practical importance on current systems.
520 AC_C_BACKSLASH_A AC_FUNC_MEMCMP AC_HEADER_DIRENT
521 AC_C_CONST AC_FUNC_SELECT_ARGTYPES AC_HEADER_STAT
522 AC_C_PROTOTYPES AC_FUNC_SETPGRP AC_HEADER_STDC
523 AC_C_STRINGIZE AC_FUNC_SETVBUF_REVERSED AC_HEADER_SYS_WAIT
524 AC_C_VOLATILE AC_FUNC_STAT AC_HEADER_TIME
525 AC_FUNC_CLOSEDIR_VOID AC_FUNC_STRFTIME AC_ISC_POSIX
526 AC_FUNC_GETPGRP AC_FUNC_UTIME_NULL AC_PROG_GCC_TRADITIONAL
527 AC_FUNC_LSTAT AC_FUNC_VPRINTF AC_STRUCT_TM
529 New programs need not use these macros. We have no current plans to
533 For compatibility with future Libtool 2.0, autoreconf will invoke
534 libtoolize with the option `--ltdl' now, if LT_CONFIG_LTDL_DIR is
537 * Major changes in Autoconf 2.59c
539 Released 2006-04-12, by Ralf Wildenhues.
541 ** The configure command now redirects standard input from /dev/null,
542 to help avoid problems with subsidiary commands that might mistakenly
543 read standard input. AS_ORIGINAL_STDIN_FD points to the original
544 standard input before this redirection, if you really want configure to
545 read from standard input.
547 ** Directory variables adjusted to recent changes in the GNU Coding Standards.
548 The following directory variables are new:
550 datarootdir read-only architecture-independent data root [PREFIX/share]
551 localedir locale-specific message catalogs [DATAROOTDIR/locale]
552 docdir documentation root [DATAROOTDIR/doc/PACKAGE]
553 htmldir html documentation [DOCDIR]
554 dvidir dvi documentation [DOCDIR]
555 pdfdir pdf documentation [DOCDIR]
556 psdir ps documentation [DOCDIR]
558 The following variables have new default values:
560 datadir read-only architecture-independent data [DATAROOTDIR]
561 infodir info documentation [DATAROOTDIR/info]
562 mandir man documentation [DATAROOTDIR/man]
564 This means that if you use any of `@datadir@', `@infodir@', or
565 `@mandir@' in a file, you will have to ensure `${datarootdir}' is
566 defined in this file. As a temporary measure, if any of those are
567 found but no mention of `datarootdir', the substitutions will be
568 replaced with values that do not contain `${datarootdir}', and a
569 warning will be issued.
571 ** @top_builddir@ is now a dir name: it is always nonempty and doesn't have
572 a trailing slash. Similar change will be made to ac_top_builddir in a
573 future release; the old style value, which matches (../)*, is (and will
574 continue to be) available as ac_top_build_prefix.
577 New macro to check for support of 'typeof' syntax a la GNU C.
579 ** AC_CHECK_DECLS_ONCE, AC_CHECK_FUNCS_ONCE, AC_CHECK_HEADERS_ONCE
580 New "once-only" variants of commonly-used macros, to make 'configure'
581 smaller and faster in common cases.
584 New macro to check for strtold with C99 semantics.
587 New macro that lets builder disable assertions at 'configure'-time.
590 Now checks for X11/Xlib.h and XrmInitialize (X proper) rather than
591 X11/Intrinsic.h and XtMalloc (Xt).
593 ** AC_PRESERVE_HELP_ORDER
594 New macro that causes `configure' to display help strings for AC_ARG_ENABLE
595 and AC_ARG_WITH arguments in one region, in the order defined. The default
596 behavior is to group options of each classes separately.
598 ** AC_PROG_CC, AC_PROG_CXX
599 No longer automatically arrange to declare the 'exit' function of C,
600 when a C++ compiler is used. Standard Autoconf macros no longer use
601 'exit', so this is no longer an issue for them. If you use C++, and
602 want to call 'exit', you'll have to arrange for its declaration
603 yourself. But we now suggest you return from 'main' instead.
605 ** AC_PROG_CC_C89, AC_PROG_CC_C99
606 New macros for ISO C99 support. AC_PROG_CC_C89 and AC_PROG_CC_C99
607 check for ANSI C89 and ISO C99 support respectively.
610 Has been unobsoleted, and will check if the compiler supports ISO
611 C99, falling back to ANSI C89 if not. ac_cv_prog_cc_stdc is
612 retained for backwards compatibility, assuming the value of
613 ac_cv_prog_cc_c99 or ac_cv_prog_cc_c89 (whichever is valid, in
616 ** AC_STRUCT_DIRENT_D_INO, AC_STRUCT_DIRENT_D_TYPE
617 New macros for checking commonly-used members of struct dirent.
620 The substituted value can now contain newlines.
623 The substitution now occurs only when @variable@ is on a line by itself,
624 optionally surrounded by spaces and tabs. The whole line is replaced.
626 ** AC_TYPE_LONG_DOUBLE, AC_TYPE_LONG_DOUBLE_WIDER
627 New macros to check for long double, and whether it is wider than double.
628 The old macro AC_C_TYPE_LONG_DOUBLE has been marked as obsolete;
629 applications should switch to the new macro.
631 ** AC_TYPE_INT8_T, AC_TYPE_INT16_T, AC_TYPE_INT32_T, AC_TYPE_INT64_T,
632 AC_TYPE_INTMAX_T, AC_TYPE_INTPTR_T, AC_TYPE_LONG_LONG_INT, AC_TYPE_SSIZE_T,
633 AC_TYPE_UINT8_T, AC_TYPE_UINT16_T, AC_TYPE_UINT32_T, AC_TYPE_UINT64_T,
634 AC_TYPE_UINTMAX_T, AC_TYPE_UINTPTR_T, AC_TYPE_UNSIGNED_LONG_LONG_INT
635 New macros to check for C99 and POSIX types.
637 ** AC_USE_SYSTEM_EXTENSIONS
638 New macro to enable extensions to Posix.
641 New macro which is defined to the name of the first declared config header
642 or undefined if no config headers have been declared yet.
645 The macro correctly handles quadrigraphs now.
647 ** AS_BOURNE_COMPATIBLE, AS_SHELL_SANITIZE, AS_CASE
648 These macros are new or published now.
651 New macro for copyright notices in testsuite files.
653 ** ALLOCA, LIBOBJS, LTLIBOBJS
654 Object names added to these variables are now prefixed with `${LIBOBJDIR}',
655 as in `${LIBOBJDIR}alloca.o'. LIBOBJDIR is meant to be defined from
656 `Makefile.in' in case the object files lie in a different directory.
657 The LIBOBJDIR feature is experimental.
660 Supports --no-recursive now.
662 ** New macros to support Erlang/OTP.
663 New macros for configuring paths to Erlang tools and libraries:
664 AC_ERLANG_PATH_ERLC, AC_ERLANG_NEED_ERLC, AC_ERLANG_PATH_ERL,
665 AC_ERLANG_NEED_ERL, AC_ERLANG_CHECK_LIB, AC_ERLANG_SUBST_ROOT_DIR,
666 AC_ERLANG_SUBST_LIB_DIR.
668 New macros for configuring installation of Erlang libraries:
669 AC_ERLANG_SUBST_INSTALL_LIB_DIR, AC_ERLANG_SUBST_INSTALL_LIB_SUBDIR.
671 ** The manual now mentions Gnulib more prominently.
673 ** New macros to support Objective C.
674 AC_PROG_OBJC, AC_PROG_OBJCPP.
676 * Major changes in Autoconf 2.59b
678 Released 2004-08-20, by Paul Eggert.
681 New macro that computes the default alignment of a type.
683 ** AC_CHECK_TOOL, AC_PATH_TOOL, AC_CHECK_TOOLS
684 When cross-compiling, these macros will give a warning if the tool
685 is not prefixed. In the future, unprefixed cross tools will not
686 be detected; please consult the info documentation for information
687 about the reason of this change.
689 ** AC_CHECK_TARGET_TOOL, AC_PATH_TARGET_TOOL, AC_CHECK_TARGET_TOOLS
690 New macros that detect programs whose name is prefixed with the
691 target type, if the build type and target type are different.
693 ** AC_REQUIRE_AUX_FILE
694 New trace macro that declares expected auxiliary files.
697 New macro that tests for a grep program that accepts as a long a line
700 ** AC_PROG_EGREP, AC_PROG_FGREP
701 These macros now require AC_PROG_GREP, and try EGREP="$GREP -E" and
702 FGREP="$GREP -F" respectively if possible, or else run a path search for
703 a program that accepts as long a line as possible.
706 New macro that tests for a sed program that truncates as few characters
709 * Major changes in Autoconf 2.59
711 Released 2003-11-04, by Akim Demaille
713 ** ac_abs_builddir etc.
714 Absolute file names were actually relative in 2.58.
716 * Major changes in Autoconf 2.58
718 Released 2003-11-04, by Akim Demaille
721 core.* files are no longer removed, as they may be valid user files.
723 ** autoreconf and auxiliary directory
724 Autoreconf creates the auxiliary directory if needed. This is
725 especially useful for initial "bootstrapping" of fresh CVS checkouts.
727 ** AC_CONFIG_MACRO_DIR
728 Use this macro to declare the directory for local M4 macros for aclocal.
731 No longer includes twice the same file in LIBOBJS if invoked
734 ** AC_CONFIG_COMMANDS
735 The directory for its first argument is automatically created. For
738 AC_CONFIG_COMMANDS([src/modules.hh], [...])
740 $top_builddir/src/ is created if needed.
742 ** Autotest and local.at
743 The optional file local.at is always included in Autotest test suites.
746 The warnings are always issued, including with cached runs.
747 This became a significant problem since aclocal and automake can
748 run autoconf behind the scene.
750 ** autoheader warnings
751 The warnings of autoheader can be turned off, using --warning.
752 For instance, -Wno-obsolete disables the complaints about acconfig.h
753 and other deprecated constructs.
756 AC_C_RESTRICT, AC_INCLUDES_DEFAULT, AC_LANG_ASSERT, AC_LANG_WERROR,
759 ** AC_DECL_SYS_SIGLIST
763 Now checks that mktime is the inverse of localtime.
765 ** Improve DJGPP portability
766 The Autoconf tools and configure behave better under DJGPP.
768 ** Present But Cannot Be Compiled
769 New FAQ section dedicated to the mystic
771 configure: WARNING: pi.h: present but cannot be compiled
772 configure: WARNING: pi.h: check for missing prerequisite headers?
773 configure: WARNING: pi.h: proceeding with the preprocessor's result
776 ** Concurrent executions of autom4te
777 autom4te now locks its internal files, which enables concurrent
778 executions of autom4te, likely to happen if automake, autoconf,
779 autoheader etc. are run simultaneously.
782 Use of Libtool 1.5 and higher is encouraged. Compatibility with
783 Libtool pre-1.4 is not checked.
786 Testsuites no longer rerun failed tests in verbose mode; instead,
787 failures are logged while the test is run.
789 In addition, expected failures can be marked as such.
791 * Major changes in Autoconf 2.57
793 Released 2002-12-03 by Paul Eggert.
795 Bug fixes for problems with AIX linker, with freestanding C compilers,
796 with GNU M4 limitations, and with obsolete copies of GNU documents.
798 The Free Documentation License has been upgraded from 1.1 to 1.2.
800 * Major changes in Autoconf 2.56
802 Released 2002-11-15 by Akim Demaille.
804 One packaging problem fixed (config/install-sh was not executable).
806 * Major changes in Autoconf 2.55
808 Released 2002-11-14 by Akim Demaille.
812 Have your configure.ac checked by autoscan ("autoscan").
813 Try the warning options ("autoreconf -fv -Wall").
817 - AC_CHECK_HEADER, AC_CHECK_HEADERS
818 More information on proper use.
820 - Writing Test Programs
822 This sections explains how to write good test sources to use with
823 AC_COMPILE_IFELSE etc. It documents AC_LANG_PROGRAM and so forth.
825 - AC_FOO_IFELSE vs. AC_TRY_FOO
827 Explains why Autoconf moves from AC_TRY_COMPILE etc. to
828 AC_COMPILE_IFELSE and AC_LANG_PROGRAM etc.
832 - Is more robust to different Gettext installations.
834 - Produces messages (when --verbose) to be understood by Emacs'
837 - Supports -W/--warnings.
840 Once the GNU Build System reinstalled, run `./config.status
841 --recheck && ./config.status && make' if possible.
845 - Supports --cache, and --no-cache.
847 - ~/.autom4te.cfg makes it possible to disable the caching mechanism
848 (autom4te.cache). See `Customizing autom4te' in the documentation.
855 Support for the obsoleted options -m, --macrodir, -l, --localdir is
856 dropped in favor of the safer --include/--prepend-include scheme.
861 AC_COMPILER_IFELSE, AC_FUNC_MBRTOWC, AC_HEADER_STDBOOL,
862 AC_LANG_CONFTEST, AC_LANG_SOURCE, AC_LANG_PROGRAM, AC_LANG_CALL,
863 AC_LANG_FUNC_TRY_LINK, AC_MSG_FAILURE, AC_PREPROC_IFELSE.
866 Obsoleted macros are kept for Autoconf backward compatibility, but
867 should be avoided in configure.ac. Running autoupdate is advised.
870 - AC_DEFINE/AC_DEFINE_UNQUOTED
872 We have to stop using the old compatibility scheme --that tried to
873 avoid useless backslashes-- because Libtool 1.4.3 contains a
875 AC_DEFINE([error_t], [int],
876 [Define to a type to use for \`error_t' if it is not
877 otherwise available.])
879 We have to quote the single quotes and backslashes with \. The old
880 compatibility scheme saw that ` was backslashed, and therefore did
881 not quote the single quote... Failure. Hence, Autoconf 2.54 is not
882 compatible with Libtool. Autoconf 2.55 is, but in some cases might
883 produce more \ than wanted.
885 Please, note that in the future the same problem will happen with
886 AC_MSG_*: use `autoreconf -f -Wall'.
890 - Portability of the Autoconf package to Solaris.
892 - Spurious warnings caused by config.status.
893 This bug is benign, but painful: on some systems (typically
894 FreeBSD), warnings such as:
896 config.status: creating Makefile
897 mv: Makefile: set owner/group (was: 1357/0): Operation not permitted
899 could be issued. This is fixed.
902 Simultaneous executions of config.status are possible again.
904 - Precious variables accumulation
906 config.status could stack several copies of the precious variables
910 ** Plans for later versions
914 The compatibility hooks with the old scheme will be completely
915 removed. Please, advice/use `--build', `--host', and `--target'
918 - AC_CHECK_HEADER, AC_CHECK_HEADERS
920 The tests will be stricter, please make sure your invocations are
925 Shell functions will gradually be introduced, probably starting with
926 Autotest. If you know machines which are in use that you suspect
927 *not* to support shell functions, please run the test suite of
928 Autoconf 2.55 on it, and report the results to
929 bug-autoconf@gnu.org.
933 Special characters in AC_MSG_* need not be quoted. Currently,
934 Autoconf has heuristics to decide when a string is escaped, or has
935 to be escaped. This scheme is fragile, and will be removed; the
936 only risk is uglified messages. Please, run `autoreconf -f -Wall'
937 to find occurrences that will be affected.
939 * Major changes in Autoconf 2.54
941 Released 2002-09-13 by Akim Demaille.
945 - autoreconf no longer changes the version of the gettext/po/intl
946 support files. It now adds the files the correspond to the
947 AM_GNU_GETTEXT_VERSION declared in configure.ac.
949 Warning: It now relies on the 'autopoint' program, which is part
950 of GNU gettext 0.11.4 and newer.
952 Please note that you need to have a GNU gettext version that
953 corresponds at least to the AM_GNU_GETTEXT_VERSION declared
954 in configure.ac. You can upgrade to newer GNU gettext versions,
955 though, without needing to change configure.ac.
957 - The -I DIR or --include=DIR option now appends DIR to the include path
958 instead of prepending; this is for consistency with other GNU tools.
959 The new -B DIR or --prepend-include=DIR option has the old behavior.
964 Now handles all the gory details about LIBOBJS and LTLIBOBJS.
965 Please, remove lines such as
967 # This is necessary so that .o files in LIBOBJS are also
968 # built via the ANSI2KNR-filtering rules.
969 LIBOBJS=`echo $LIBOBJS|sed 's/\.o /\$U.o /g;s/\.o$/\$U.o/'`
971 and read the `AC_LIBOBJ vs LIBOBJS' section. Do not define U in
972 your Makefiles either.
974 - AC_CONFIG_LINKS now makes copies if it can't make links.
976 - AC_FUNC_FNMATCH now tests only for POSIX compatibility, reverting to
977 Autoconf 2.13 behavior. The new macro AC_FUNC_FNMATCH_GNU also
978 tests for GNU extensions to fnmatch, and replaces fnmatch if needed.
980 - AC_FUNC_SETVBUF_REVERSED no longer fails when cross-compiling.
982 - AC_PROG_CC_STDC is integrated into AC_PROG_CC.
984 - AC_PROG_F77 default search no longer includes cf77 and cfg77.
988 AC_C_BACKSLASH_A, AC_CONFIG_LIBOBJ_DIR, AC_GNU_SOURCE,
989 AC_PROG_EGREP, AC_PROG_FGREP, AC_REPLACE_FNMATCH,
990 AC_FUNC_FNMATCH_GNU, AC_FUNC_REALLOC, AC_TYPE_MBSTATE_T.
993 looks for getloadavg.c in the CONFIG_LIBOBJ_DIR.
996 Now defines HAVE_MALLOC to 0 if `malloc' does not work, and asks
997 for an AC_LIBOBJ replacement.
1001 - Spurious complaints from `m4_bmatch' about invalid regular
1002 expressions are suppressed.
1004 - Empty top_builddirs are properly handled.
1006 - AC_CHECK_MEMBER works correctly when the member is an aggregate.
1009 Now colon in the optional path arguments are properly handled.
1011 ** Improved portability
1013 - Both Autoconf the package, and the scripts it produces, should run
1014 more reliably with Zsh. Bear in mind it is the default Bourne shell
1017 - Autoconf and the scripts it produces no longer assume the existence of
1018 the obsolescent commands egrep and fgrep.
1022 - Limitations of Make
1026 The GNATS base moved to
1027 http://bugs.gnu.org/cgi-bin/gnatsweb.pl?database=autoconf
1028 (It is no longer available, though.)
1033 Now contains the list of ouput variables and files (AC_SUBST,
1036 * Major changes in Autoconf 2.53
1038 Released 2002-03-08 by Akim Demaille.
1042 Perl 5.005_03 or later is required: autom4te is written in Perl and is
1043 needed by autoconf. autoheader, autoreconf, ifnames, and autoscan are
1049 Argument requirements, output variables, defined macros.
1050 - M4sugar, M4sh, Autotest
1052 - Double quoting macros
1053 AC_TRY_CPP, AC_TRY_COMPILE, AC_TRY_LINK and AC_TRY_RUN.
1055 The Autoconf manual is now distributed under the terms of the GNU FDL.
1056 - Section `Hosts and Cross-Compilation'
1057 Explains the rationale for the 2.5x changes in the cross-compilation
1058 chain, and in the relationships between build, host, and target
1060 Emphasizes that `cross-compilation' == `--host is given'.
1061 If you are working on compilers etc., be sure to read this section.
1062 - Section `AC_LIBOBJ vs. LIBOBJS'
1063 Explains why assigning LIBOBJS directly is now an error.
1064 Details how to update the code.
1069 Now used instead of hard coded line numbers.
1070 This eases the comparison of `configure's, and diminishes the
1071 pressure over control version archives.
1072 Automatic replacement for shells that don't support this feature.
1073 - New output variables
1074 @builddir@, @top_builddir@, @abs_srcdir@, @abs_top_srcdir@, @abs_builddir@,
1079 Autoconf and Autotest modes are provided.
1084 New, used by the Autoconf suite to cache and speed up most processing.
1086 Supported by autom4te, autoconf and autoheader.
1088 Replaces --autoconf-dir and --localdir in autoconf, autoheader,
1089 autoupdate, and autoreconf.
1091 No longer passes --cygnus, --foreign, --gnits, --gnu, --include-deps:
1092 automake options are to be given via AUTOMAKE_OPTIONS.
1094 Runs gettextize and libtoolize when appropriate.
1096 --m4dir is no longer supported.
1098 Now runs only in the specified directories, defaulting to `.',
1099 but understands AC_CONFIG_SUBDIRS for dependent directories.
1100 Before, it used to run on all the `configure.ac' found in the
1102 Independent packages are properly updated.
1106 - The top level $prefix is propagated to the AC_CONFIG_SUBDIRS configures.
1108 Under the user pressure, $? is finally available. Probably a mistake.
1109 - AC_F77_LIBRARY_LDFLAGS now supports the HP/UX f90 compiler.
1110 - Precious variables accumulation
1111 config.status could stack several copies of the precious variables
1113 - AC_PATH_PROG and family.
1114 Works properly when given a literal path.
1116 Somewhere since 2.13, the result had been reversed.
1120 - AC_C_BIGENDIAN supports the cross-compiling case.
1121 - AC_C_BIGENDIAN accepts ACTION-IF-TRUE, ACTION-IF-FALSE, and
1122 ACTION-IF-UNKNOWN arguments. All are facultative, and the default
1123 for ACTION-IF-TRUE is to define WORDS_BIGENDIAN like AC_C_BIGENDIAN
1125 - AC_C_LONG_DOUBLE now succeeds only if `long double' has more range or
1126 precision than `double'.
1131 It now defines the preprocessor symbols PACKAGE_NAME,
1132 PACKAGE_TARNAME, PACKAGE_VERSION, PACKAGE_STRING, and
1136 Admits a fourth optional parameter: the tar name.
1138 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS.
1139 Provide the user with srcdir, ac_srcdir, ac_top_srcdir, ac_builddir,
1140 ac_top_builddir, ac_abs_srcdir, ac_abs_top_srcdir, ac_abs_builddir,
1141 ac_abs_top_builddir.
1143 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS and AC_OUTPUT.
1144 Are much less expensive when using long lists of files.
1147 Works with shell variables, and non alphanumeric names.
1151 - AC_FUNC_STRERROR_R now sets STRERROR_R_CHAR_P, not HAVE_WORKING_STRERROR_R,
1152 because POSIX 1003.1-200x draft 7 says strerror_r returns int, not char *.
1154 - AC_FUNC_STRTOD substitutes POW_LIB.
1159 * Major changes in Autoconf 2.52
1161 Released 2001-07-18 by Akim Demaille.
1166 This feature was present in autoconf 2.50 but was not documented.
1167 For example, `@<:@' is translated to `[' just before output. This
1168 is useful when writing strings that contain unbalanced quotes, or
1169 other hard-to-quote constructs.
1170 - m4_pattern_forbid, m4_pattern_allow
1171 - Tips for upgrading from 2.13.
1172 - Using autoscan to maintain a configure.ac.
1175 - Now include stdint.h.
1176 - sys/types.h and sys/stat.h are guarded.
1177 - strings.h is included if available, and not conflicting with string.h.
1180 - The test suite is more robust and presents less false failures.
1181 - Invocation of GNU M4 now robust to POSIXLY_CORRECT.
1182 - configure accepts --prefix='' again.
1183 - AC_CHECK_LIB works properly when its first argument is not a
1185 - HAVE_INTTYPES_H is defined only if not conflicting with sys/types.h.
1186 - build_, host_, and target_alias are AC_SUBST as in 2.13.
1187 - AC_ARG_VAR properly propagates precious variables inherited from the
1188 environment to ./config.status.
1189 - Using --program-suffix/--program-prefix is portable.
1190 - Failures to detect the default compiler's output extension are less
1192 - `config.status foo' works properly when `foo' depends on variables
1193 set in an AC_CONFIG_THING INIT-CMD.
1194 - autoheader is more robust to broken input.
1195 - Fixed Fortran name-mangling and link tests on a number of systems,
1196 e.g. NetBSD; see AC_F77_DUMMY_MAIN, below.
1199 - AC_CHECK_HEADER and AC_CHECK_HEADERS support a fourth argument to
1200 specify pre-includes. In this case, the headers are compiled with
1201 cc, not merely preprocessed by cpp. Therefore it is the _usability_
1202 of a header which is checked for, not just its availability.
1203 - AC_ARG_VAR refuses to run configure when precious variables have
1205 - Versions of compilers are dumped in the logs.
1206 - AC_CHECK_TYPE recognizes use of `foo_t' as a replacement type.
1209 - AC_PATH_XTRA only adds -ldnet to $LIBS if it's needed to link.
1210 - AC_FUNC_WAIT3 and AC_SYS_RESTARTABLE_SYSCALLS are obsoleted.
1211 - AM_FUNC_ERROR_AT_LINE, AM_FUNC_FNMATCH, AM_FUNC_MKTIME,
1212 AM_FUNC_OBSTACK, and AM_FUNC_STRTOD are now activated.
1213 Be sure to read `Upgrading from Version 2.13' to understand why
1214 running `autoupdate' is needed.
1215 - AC_F77_DUMMY_MAIN, AC_F77_MAIN: new macros to detect whether
1216 a main-like routine is required/possible when linking C/C++ with
1217 Fortran. Users of e.g. AC_F77_WRAPPERS should be aware of these.
1218 - AC_FUNC_GETPGRG behaves better when cross-compiling.
1220 * Major changes in Autoconf 2.51
1221 There was no release of Autoconf 2.51 since some packagers had used
1222 this version number without permission to ship intermediary versions
1223 of 2.50. The version was skipped to avoid confusion.
1225 * Major changes in Autoconf 2.50
1227 Released 2001-05-21 by Akim Demaille.
1229 ** Lots of bug fixes
1230 There have been far too many to enumerate them here. Check out
1231 ChangeLog if you really want to know more.
1233 ** Improved documentation
1234 In particular, portability issues are better covered.
1237 All the standard GNU Makefile targets are supported. The layout has
1238 changed: m4/ holds the M4 extensions Autoconf needs for its
1239 configuration, doc/ contains the documentation, and tests/ contains
1242 ** Man pages are provided
1243 For autoconf, autoreconf, autoupdate, autoheader, autoscan, ifnames,
1244 config.guess, config.sub.
1248 Provides a safe and powerful means to trace the macro uses. This
1249 provide the parsing layer for tools which need to `study'
1253 Specify what category of warnings should be enabled.
1255 - When recursing into subdirectories, try for configure.gnu before
1256 configure to adapt for packages not using autoconf on case-insensitive
1260 More errors are now caught (circular AC_REQUIRE dependencies,
1261 AC_DEFINE in the action part of an AC_CACHE_CHECK, too many pops
1262 etc.). In addition, their location and call stack are given.
1265 autoupdate is much more powerful, and is able to provide the glue code
1266 which might be needed to move from an old macro to its newer
1269 You are strongly encouraged to use it to modernize both your
1270 `configure.in' and your .m4 extension files.
1273 The internal machinery of autoheader has completely changed. As a
1274 result, using `acconfig.h' should be considered to be obsoleted, and
1275 you are encouraged to get rid of it using the AH macros.
1280 ** Fortran 77 compilers
1281 Globally, the support for Fortran 77 is considerably improved.
1283 Support for automatically determining a Fortran 77 compiler's
1284 name-mangling scheme. New CPP macros F77_FUNC and F77_FUNC_ are
1285 provided to wrap C/C++ identifiers, thus making it easier and more
1286 transparent for C/C++ to call Fortran 77 routines, and Fortran 77 to
1287 call C/C++ routines. See the Texinfo documentation for details.
1290 The test suite no longer uses DejaGNU. It should be easy to submit
1291 test cases in this new framework.
1294 - --help, --help=long, -hl
1295 no longer dumps useless items.
1297 lists only specific options.
1298 - --help=recursive, -hr
1299 displays the help of all the embedded packages.
1300 - Remembers environment variables when reconfiguring.
1301 The previous scheme to set envvar before running configure was
1303 what prevented configure from remembering the environment in which
1304 it was run, therefore --recheck was run in an inconsistent
1305 environment. Now, one should run
1307 and then --recheck will work properly. Variables declared with
1308 AC_ARG_VAR are also preserved.
1310 $build defaults to `config.guess`, $host to $build, and then $target
1312 Cross-compilation is a global status of the package, it no longer
1313 depends upon the current language.
1314 Cross compilation is enabled iff the user specified `--host'.
1315 `configure' now fails if it can't run the executables it compiles,
1316 unless cross-compilation is enabled.
1318 The cache file is disabled by default. The new options
1319 `--config-cache', `-C' set the cache to `config.cache'.
1323 Much faster on most architectures.
1324 - concurrent executions
1325 It is safe to use `make -j' with config.status.
1326 - human interface improved
1327 It is possible to invoke
1328 ./config.status foobar
1329 instead of the former form (still valid)
1330 CONFIG_COMMANDS= CONFIG_HEADERS= CONFIG_LINKS= \
1331 CONFIG_FILES=foobar:foo.in:bar.in \
1333 The same holds for configuration headers and links.
1334 You can instantiate unknown files and headers:
1335 ./config.status --header foo.h:foo.h.in --file bar:baz
1336 - has a useful --help
1337 - accepts special file name "-" for stdin/stdout
1342 Specify additional copyright information.
1345 Now expects the identity of the package as argument.
1349 Most macros, if not all, now strictly follow the `one quotation
1350 level' rule. This results in a more predictable expansion.
1353 A sly bug in the AC_REQUIRE machinery, which could produce incorrect
1354 configure scripts, was fixed by Axel Thimm.
1358 Document and ask for the registration of an envvar.
1361 Specifies the file which `configure' should look for when trying to
1362 find the source tree (used to be handled by AC_INIT).
1364 - AC_CONFIG_COMMANDS
1365 To add new actions to config.status. Should be used instead of
1369 Replaces AC_LINK_FILES.
1371 - AC_CONFIG_HEADERS, AC_CONFIG_COMMANDS, AC_CONFIG_SUBDIRS,
1372 AC_CONFIG_LINKS, and AC_CONFIG_FILES
1373 They now obey sh: you should no longer use shell variables as
1374 argument. Instead of
1376 test "$package_foo_enabled" = yes && $my_subdirs="$my_subdirs foo"
1377 AC_CONFIG_SUBDIRS($my_subdirs)
1381 if test "$package_foo_enabled" = yes; then
1382 AC_CONFIG_SUBDIRS(foo)
1386 To format an Autoconf macro's help string so that it looks pretty
1387 when the user executes `configure --help'.
1390 ** Generic Test Macros
1392 The interface of the AC_CHECK families of macros (decl, header,
1393 type, member, func) is now uniform. They support the same set of
1396 - AC_CHECK_DECL, AC_CHECK_DECLS
1397 To check whether a symbol is declared.
1399 - AC_CHECK_SIZEOF, AC_C_CHAR_UNSIGNED.
1400 No longer need a cross-compilation default.
1403 The test it performs is much more robust than previously, and makes
1404 it possible to test builtin types in addition to typedefs.
1405 It is now schizophrenic:
1406 - AC_CHECK_TYPE(TYPE, REPLACEMENT)
1407 remains for backward compatibility, but its use is discouraged.
1408 - AC_CHECK_TYPE(TYPE, IF-FOUND, IF-NOT-FOUND, INCLUDES)
1409 behaves exactly like the other AC_CHECK macros.
1412 Checks whether given types are supported by the system.
1414 - AC_CHECK_MEMBER, AC_CHECK_MEMBERS
1415 Check for given members in aggregates (e.g., pw_gecos in struct
1419 Checks if the compiler supports ISO C, included when needs special
1423 Checking whether the preprocessor indicates missing includes by the
1424 error code. stderr is checked by AC_TRY_CPP only as a fallback.
1427 Takes a language as argument and replaces AC_LANG_C,
1428 AC_LANG_CPLUSPLUS and AC_LANG_FORTRAN77.
1430 - AC_LANG_PUSH, AC_LANG_POP
1431 Are preferred to AC_LANG_SAVE, AC_LANG_RESTORE.
1434 - AC_FUNC_CHOWN, AC_FUNC_MALLOC, AC_FUNC_STRERROR_R,
1435 AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK, AC_FUNC_STAT, AC_FUNC_LSTAT,
1436 AC_FUNC_ERROR_AT_LINE, AC_FUNC_OBSTACK, AC_FUNC_STRTOD, AC_FUNC_FSEEKO.
1440 Sets GETGROUPS_LIBS.
1442 - AC_FUNC_GETLOADAVG
1443 Defines `HAVE_STRUCT_NLIST_N_UN_N_NAME' instead of `NLIST_NAME_UNION'.
1446 Now integrates `AC_DECL_YYTEXT' which is obsoleted.
1449 Arrange for large-file support.
1451 - AC_EXEEXT, AC_OBJEXT
1452 You are no longer expected to use them: their computation is
1453 performed by default.
1455 ** C++ compatibility
1456 Every macro has been revisited in order to support at best CC=c++.
1458 Major changes in Autoconf 2.14:
1459 There was no release of GNU Autoconf 2.14.
1461 Major changes in Autoconf 2.13:
1463 Released 1999-05-01 by Ben Elliston.
1465 * Support for building on Win32 systems where the only available C or
1466 C++ compiler is the Microsoft Visual C++ command line compiler
1467 (`cl'). Additional support for building on Win32 systems which are
1468 using the Cygwin or Mingw32 environments.
1469 * Support for alternative object file and executable file extensions.
1470 On Win32, for example, these are .obj and .exe. These are discovered
1471 using AC_OBJEXT and AC_EXEEXT, which substitute @OBJEXT@ and
1472 @EXEEXT@ in the output, respectively.
1473 * New macros: AC_CACHE_LOAD, AC_CACHE_SAVE, AC_FUNC_SELECT_ARGTYPES,
1474 AC_VALIDATE_CACHED_SYSTEM_TUPLE, AC_SEARCH_LIBS, AC_TRY_LINK_FUNC,
1475 AC_C_STRINGIZE, AC_CHECK_FILE(S), AC_PROG_F77 (and friends).
1476 * AC_DEFINE now has an optional third argument for a description to be
1477 placed in the config header input file (e.g. config.h.in).
1478 * The C++ code fragment compiled for the C++ compiler test had to be
1479 improved to include an explicit return type for main(). This was
1480 causing failures on systems using recent versions of the EGCS C++
1482 * Fixed an important bug in AC_CHECK_TYPE that would cause a configure
1483 script to report that `sometype_t' was present when only `type_t'
1485 * Merge of the FSF version of config.guess and config.sub to modernize
1486 these scripts. Add support for a few new hosts in config.guess.
1487 Incorporate latest versions of install-sh, mkinstalldirs and
1488 texinfo.tex from the FSF.
1489 * autoreconf is capable of running automake if necessary (and
1491 * Support for Fortran 77. See the Texinfo documentation for details.
1492 * Bug fixes and workarounds for quirky bugs in vendor utilities.
1494 Major changes in Autoconf 2.12:
1496 Released 1996-11-26 by David J. MacKenzie
1498 * AC_OUTPUT and AC_CONFIG_HEADER can create output files by
1499 concatenating multiple input files separated by colons, like so:
1500 AC_CONFIG_HEADER(config.h:conf.pre:config.h.in:conf.post)
1501 AC_OUTPUT(Makefile:Makefile.in:Makefile.rules)
1502 The arguments may be shell variables, to compute the lists on the fly.
1503 * AC_LINK_FILES and AC_CONFIG_SUBDIRS may be called multiple times.
1504 * New macro AC_OUTPUT_COMMANDS adds more commands to run in config.status.
1507 Major changes in Autoconf 2.11:
1509 Released November 18th, 1996, by David J. MacKenzie
1511 * AC_PROG_CC and AC_PROG_CXX check whether the compiler works.
1512 They also default CFLAGS/CXXFLAGS to "-g -O2" for gcc, instead of "-g -O".
1513 * AC_REPLACE_FUNCS defines HAVE_foo if the system has the function `foo'.
1514 * AC_CONFIG_HEADER expands shell variables in its argument.
1515 * New macros: AC_FUNC_FNMATCH, AC_FUNC_SETPGRP.
1516 * The "checking..." messages and the source code for test programs that
1517 fail are saved in config.log.
1518 * Another workaround has been added for seds with small command length limits.
1519 * config.sub and config.guess recognize more system types.
1522 Major changes in Autoconf 2.10:
1524 Released May 7th, 1996, by Roland McGrath
1527 * The cache variable names used by `AC_CHECK_LIB(LIB, FUNC, ...)' has
1528 changed: now $ac_cv_lib_LIB_FUNC, previously $ac_cv_lib_LIB.
1530 Major changes in Autoconf 2.9:
1532 Released March 16th, 1996, by Roland McGrath
1536 Major changes in Autoconf 2.8:
1538 Released March 8th, 1996, by Roland McGrath
1542 Major changes in Autoconf 2.7:
1544 Released November 22nd, 1995, by David J. MacKenzie
1548 Major changes in Autoconf 2.6:
1550 Released November 20th, 1995, by David J. MacKenzie
1554 Major changes in Autoconf 2.5:
1556 Released November 17th, 1995, by Roland McGrath
1558 * New configure options --bindir, --libdir, --datadir, etc., with
1559 corresponding output variables.
1560 * New macro: AC_CACHE_CHECK, to make using the cache easier.
1561 * config.log contains the command being run as well as any output from it.
1562 * AC_CHECK_LIB can check for libraries with "." or "/" or "+" in their name.
1563 * AC_PROG_INSTALL doesn't cache a name for install-sh, for sharing caches.
1564 * AC_CHECK_PROG, AC_PATH_PROG, AC_CHECK_PROGS, AC_PATH_PROGS, and
1565 AC_CHECK_TOOL can search a path other than $PATH.
1566 * AC_CHECK_SIZEOF takes an optional size to use when cross-compiling.
1568 Major changes in Autoconf 2.4:
1570 Released June 14th, 1995, by David J. MacKenzie
1572 * Fix a few bugs found by Emacs testers.
1574 Major changes in Autoconf 2.3:
1576 Released March 27th, 1995, by David J. MacKenzie
1578 * Fix the cleanup trap in several ways.
1579 * Handle C compilers that are picky about option placement.
1580 * ifnames gets the version number from the right directory.
1582 Major changes in Autoconf 2.2:
1584 Released March 8th, 1995, by David J. MacKenzie
1586 * The ifnames utility is much faster but requires a "new awk" interpreter.
1587 * AC_CHECK_LIB and AC_HAVE_LIBRARY check and add the new
1588 library before existing libs, not after, in case it uses them.
1589 * New macros: AC_FUNC_GETPGRP, AC_CHECK_TOOL.
1590 * Lots of bug fixes.
1591 * Many additions to the TODO file :-)
1593 Major changes in Autoconf 2.1:
1595 Released November 4th, 1994, by David J. MacKenzie
1598 * More explanations in the manual.
1599 * Fix a spurious failure in the testsuite.
1600 * Clarify some warning messages.
1601 * autoreconf by default only rebuilds configure and config.h.in files
1602 that are older than any of their particular input files; there is a
1603 --force option to use after installing a new version of Autoconf.
1605 Thanks to everybody who's submitted changes and additions to Autoconf!
1606 I've incorporated many of them, and am still considering others for
1607 future releases -- but I didn't want to postpone this release indefinitely.
1609 Caution: don't indiscriminately rebuild configure scripts with
1610 Autoconf version 2. Some configure.in files need minor adjustments to
1611 work with it; the documentation has a chapter on upgrading. A few
1612 configure.in files, including those for GNU Emacs and the GNU C
1613 Library, need major changes because they relied on undocumented
1614 internals of version 1. Future releases of those packages will have
1615 updated configure.in files.
1617 It's best to use GNU M4 1.3 (or later) with Autoconf version 2.
1618 Autoconf now makes heavy use of M4 diversions, which were implemented
1619 inefficiently in GNU M4 releases before 1.3.
1621 Major changes in Autoconf 2.0:
1623 Released October 26th, 1994, by David J. MacKenzie
1625 ** New copyright terms:
1626 * There are no restrictions on distribution or use of configure scripts.
1629 * Autoconf manual is reorganized to make information easier to find
1630 and has several new indexes.
1631 * INSTALL is reorganized and clearer and is now made from Texinfo source.
1634 * autoscan to generate a preliminary configure.in for a package by
1635 scanning its source code for commonly used nonportable functions,
1636 programs, and header files.
1637 * ifnames to list the symbols used in #if and #ifdef directives in a
1639 * autoupdate to update a configure.in to use the version 2 macro names.
1640 * autoreconf to recursively remake configure and configuration header
1641 files in a source tree.
1643 ** Changed utilities:
1644 * autoheader can take pieces of acconfig.h to replace config.h.{top,bot}.
1645 * autoconf and autoheader can look for package-local definition files
1646 in an alternate directory.
1649 * AC_CACHE_VAL to share results of tests between configure runs.
1650 * AC_DEFUN to define macros, automatically AC_PROVIDE them, and ensure
1651 that macros invoked with AC_REQUIRE don't interrupt other macros.
1652 * AC_CONFIG_AUX_DIR, AC_CANONICAL_SYSTEM, AC_CANONICAL_HOST, AC_LINK_FILES to
1653 support deciding unguessable features based on the host and target types.
1654 * AC_CONFIG_SUBDIRS to recursively configure a source tree.
1655 * AC_ARG_PROGRAM to use the options --program-prefix,
1656 --program-suffix, and --program-transform-name to change the names
1657 of programs being installed.
1658 * AC_PREFIX_DEFAULT to change the default installation prefix.
1659 * AC_TRY_COMPILE to compile a test program without linking it.
1660 * AC_CHECK_TYPE to check whether sys/types.h or stdlib.h defines a given type.
1661 * AC_CHECK_LIB to check for a particular function and library.
1662 * AC_MSG_CHECKING and AC_MSG_RESULT to print test results, on a single line,
1663 whether or not the test succeeds. They obsolete AC_CHECKING and AC_VERBOSE.
1664 * AC_SUBST_FILE to insert one file into another.
1665 * AC_FUNC_MEMCMP to check whether memcmp is 8-bit clean.
1666 * AC_FUNC_STRFTIME to find strftime even if it's in -lintl.
1667 * AC_FUNC_GETMNTENT to find getmntent even if it's in -lsun or -lseq.
1668 * AC_HEADER_SYS_WAIT to check whether sys/wait.h is POSIX.1 compatible.
1671 * Many macros renamed systematically, but old names are accepted for
1672 backward compatibility.
1673 * AC_OUTPUT adds the "automatically generated" comment to
1674 non-Makefiles where it finds @configure_input@ in an input file, to
1675 support files with various comment syntaxes.
1676 * AC_OUTPUT does not replace "prefix" and "exec_prefix" in generated
1677 files when they are not enclosed in @ signs.
1678 * AC_OUTPUT allows the optional environment variable CONFIG_STATUS to
1679 override the file name "config.status".
1680 * AC_OUTPUT takes an optional argument for passing variables from
1681 configure to config.status.
1682 * AC_OUTPUT and AC_CONFIG_HEADER allow you to override the input-file names.
1683 * AC_OUTPUT automatically substitutes the values of CFLAGS, CXXFLAGS,
1684 CPPFLAGS, and LDFLAGS from the environment.
1685 * AC_PROG_CC and AC_PROG_CXX now set CFLAGS and CXXFLAGS, respectively.
1686 * AC_PROG_INSTALL looks for install-sh or install.sh in the directory
1687 specified by AC_CONFIG_AUXDIR, or srcdir or srcdir/.. or
1688 srcdir/../.. by default.
1689 * AC_DEFINE, AC_DEFINE_UNQUOTED, and AC_SUBST are more robust and smaller.
1690 * AC_DEFINE no longer prints anything, because of the new result reporting
1691 mechanism (AC_MSG_CHECKING and AC_MSG_RESULT).
1692 * AC_VERBOSE pays attention to --quiet/--silent, not --verbose.
1693 * AC_ARG_ENABLE and AC_ARG_WITH support whitespace in the arguments to
1694 --enable- and --with- options.
1695 * AC_CHECK_FUNCS and AC_CHECK_HEADERS take optional shell commands to
1696 execute on success or failure.
1697 * Checking for C functions in C++ works.
1700 * AC_REMOTE_TAPE and AC_RSH removed; too specific to tar and cpio, and
1701 better maintained with them.
1702 * AC_ARG_ARRAY removed because no one was likely using it.
1703 * AC_HAVE_POUNDBANG replaced with AC_SYS_INTERPRETER, which doesn't
1704 take arguments, for consistency with all of the other specific checks.
1707 * Comes with config.sub and config.guess, and uses them optionally.
1708 * Uses config.cache to cache test results. An alternate cache file
1709 can be selected with the --cache-file=FILE option.
1710 * Uses optional shell scripts $prefix/share/config.site and
1711 $prefix/etc/config.site to perform site or system specific initializations.
1712 * configure saves compiler output to ./config.log for debugging.
1713 * New files autoconf.m4 and autoheader.m4 load the other Autoconf macros.
1714 * acsite.m4 is the new name for the system-wide aclocal.m4.
1715 * Has a DejaGnu test suite.
1717 Major changes in Autoconf 1.11:
1719 * AC_PROG_INSTALL calls install.sh with the -c option.
1720 * AC_SET_MAKE cleans up after itself.
1721 * AC_OUTPUT sets prefix and exec_prefix if they weren't set already.
1722 * AC_OUTPUT prevents shells from looking in PATH for config.status.
1724 Plus a few other bug fixes.
1726 Major changes in Autoconf 1.10:
1728 * autoheader uses config.h.bot if present, analogous to config.h.top.
1729 * AC_PROG_INSTALL looks for install.sh in srcdir or srcdir/.. and
1731 * AC_PROG_CXX looks for cxx as a C++ compiler.
1733 Plus several bugs fixed.
1735 Major changes in Autoconf 1.9:
1737 * AC_YYTEXT_POINTER replaces AC_DECLARE_YYTEXT.
1738 * AC_SIZEOF_TYPE generates the cpp symbol name automatically,
1739 and autoheader generates entries for those names automatically.
1740 * AC_FIND_X gets the result from xmkmf correctly.
1741 * AC_FIND_X assumes no X if --without-x was given.
1742 * AC_FIND_XTRA adds libraries to the variable X_EXTRA_LIBS.
1743 * AC_PROG_INSTALL finds OSF/1 installbsd.
1745 Major changes in Autoconf 1.8:
1748 * New macros AC_LANG_C, AC_LANG_CPLUSPLUS, AC_LANG_SAVE, AC_LANG_RESTORE,
1749 AC_PROG_CXX, AC_PROG_CXXCPP, AC_REQUIRE_CPP
1750 for checking both C++ and C features in one configure script.
1751 * New macros AC_CHECKING, AC_VERBOSE, AC_WARN, AC_ERROR for printing messages.
1752 * New macros AC_FIND_XTRA, AC_MMAP, AC_SIZEOF_TYPE, AC_PREREQ,
1753 AC_SET_MAKE, AC_ENABLE.
1756 * AC_FIND_X looks for X in more places.
1757 * AC_PROG_INSTALL defaults to install.sh instead of cp, if it's in srcdir.
1758 install.sh is distributed with Autoconf.
1759 * AC_DECLARE_YYTEXT has been removed because it can't work, pending
1760 a rewrite of quoting in AC_DEFINE.
1761 * AC_OUTPUT adds its comments in C format when substituting in C files.
1762 * AC_COMPILE_CHECK protects its ECHO-TEXT argument with double quotes.
1764 ** New or changed command line options:
1765 * configure accepts --enable-FEATURE[=ARG] and --disable-FEATURE options.
1766 * configure accepts --without-PACKAGE, which sets withval=no.
1767 * configure accepts --x-includes=DIR and --x-libraries=DIR.
1768 * Giving --with-PACKAGE no argument sets withval=yes instead of withval=1.
1769 * configure accepts --help, --version, --silent/--quiet, --no-create options.
1770 * configure accepts and ignores most other Cygnus configure options, and
1771 warns about unknown options.
1772 * config.status accepts --help, --version options.
1774 ** File names and other changes:
1775 * Relative srcdir values are not made absolute.
1776 * The values of @prefix@ and @exec_prefix@ and @top_srcdir@ get substituted.
1777 * Autoconf library files are installed in ${datadir}/autoconf, not ${datadir}.
1778 * autoheader optionally copies config.h.top to the beginning of config.h.in.
1779 * The example Makefile dependencies for configure et al. work better.
1780 * Namespace cleanup: all shell variables used internally by Autoconf
1781 have names beginning with `ac_'.
1783 More big improvements are in process for future releases, but have not
1784 yet been (variously) finished, integrated, tested, or documented enough
1787 Major changes in Autoconf 1.7:
1789 * New macro AC_OBSOLETE.
1790 * Bugs in Makefile.in fixed.
1791 * AC_LONG_FILE_NAMES improved.
1793 Major changes in Autoconf 1.6:
1795 * New macro AC_LONG_64_BITS.
1796 * Multiple .h files can be created.
1797 * AC_FIND_X looks for X files directly if it doesn't find xmkmf.
1798 * AC_ALLOCA defines C_ALLOCA if using alloca.c.
1799 * --with-NAME can take a value, e.g., --with-targets=sun4,hp300bsd.
1800 * Unused --no-create option to configure removed.
1801 * autoheader doesn't change the timestamp of its output file if
1802 the file didn't change.
1803 * All macros that look for libraries now use AC_HAVE_LIBRARY.
1804 * config.status checks three optional environment variables to
1805 modify its behavior.
1806 * The usual bug fixes.
1808 Major changes in Autoconf 1.5:
1810 * New macros AC_FIND_X, AC_OFF_T, AC_STAT_MACROS_BROKEN, AC_REVISION.
1811 * autoconf and autoheader scripts have GNU standards conforming
1812 --version and --help options (they print their message and exit).
1815 Major changes in Autoconf 1.4:
1817 * New macros AC_HAVE_POUNDBANG, AC_TIME_WITH_SYS_TIME, AC_LONG_DOUBLE,
1818 AC_GETGROUPS_T, AC_DEFINE_UNQUOTED.
1819 * autoconf and autoheader use the M4 environment variable to determine the
1820 name of the M4 program to use.
1821 * The --macrodir option to autoconf and autoheader specifies the directory
1822 in which acspecific.m4, acgeneral.m4, etc. reside if not the default.
1823 * autoconf and autoheader can take `-' as their file names, which means to
1824 read stdin as input.
1825 * Resulting configure scripts can take a --verbose option which causes them
1826 to print the results of their tests.
1827 * AC_DEFINE quotes its second argument in such a way that spaces, magic
1828 shell characters, etc. will be preserved during various stages of
1829 expansion done by the shell. If you don't want this, use
1830 AC_DEFINE_UNQUOTED instead.
1831 * Much textual processing done with external calls to tr and sed have been
1832 internalized with builtin M4 `patsubst' and `translit' calls.
1833 * AC_OUTPUT doesn't hardwire the file names it outputs. Instead, you can
1834 set the shell variables `gen_files' and `gen_config' to the list of
1835 file names to output.
1836 * AC_DECLARE_YYTEXT does an AC_SUBST of `LEX_OUTPUT_ROOT', which may be
1837 "lex.yy" or "lexyy", depending on the system.
1838 * AC_PROGRAMS_CHECK takes an optional third arg. If given, it is used as
1840 * If AC_ALLOCA chooses alloca.c, it also defines STACK_DIRECTION.
1841 * AC_CONST works much more reliably on more systems.
1844 Major changes in Autoconf 1.3:
1846 configure no longer requires awk for packages that use a config.h.
1847 Support handling --with-PACKAGE options.
1848 New `autoheader' script to create `config.h.in' from `configure.in'.
1849 Ignore troublesome -lucb and -lPW when searching for alloca.
1850 Rename --exec_prefix to --exec-prefix for GNU standards conformance.
1851 Improve detection of STDC library.
1852 Add AC_HAVE_LIBRARY to check for non-default libraries.
1853 Function checking should work with future GNU libc releases.
1855 Major changes in Autoconf 1.2:
1857 The --srcdir option is now usually unnecessary.
1858 Add a file containing sample comments describing CPP macros.
1859 A comment in config.status tells which host it was configured on.
1860 Substituted variable values can now contain commas.
1861 Fix bugs in various feature checks.
1863 Major changes in Autoconf 1.1:
1865 Added AC_STRCOLL macro.
1866 Made AC_GETLOADAVG check for more things.
1867 AC_OUTPUT argument is now optional.
1872 Copyright (C) 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002,
1873 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free Software Foundation,
1876 Copying and distribution of this file, with or without modification,
1877 are permitted in any medium without royalty provided the copyright
1878 notice and this notice are preserved. This file is offered as-is,
1879 without warranty of any kind.