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, AS_CASE, and AS_FOR have been taught to avoid syntax errors
7 even when given arguments that expand to just whitespace.
9 ** Ensure AT_CHECK can support commands that include a # given with
10 proper m4 quoting. For shell comments, this is a new feature; for
11 non-shell comments, this fixes a regression introduced in 2.63b.
13 ** The macro AT_CHECK now understands the concept of hard failure. If
14 a test exits with an unexpected status 99, cleanup actions for the
15 test are inhibited and the test is treated as a failure regardless
16 of AT_XFAIL_IF. It also understands the new directives
17 ignore-nolog, stdout-nolog, and stderr-nolog.
19 ** The autotest macro AT_CHECK_NOESCAPE is now documented.
21 ** The following documented m4sugar macros are new:
22 m4_argn m4_default_nblank m4_default_nblank_quoted m4_ifblank
25 * Major changes in Autoconf 2.63b (2009-03-31) [beta]
26 Released by Eric Blake, based on git versions 2.63.*.
28 ** The manual is now shipped under the terms of the GNU FDL 1.3.
30 ** AC_REQUIRE now detects the case of an outer macro which first expands
31 then later indirectly requires the same inner macro. Previously,
32 this case led to silent out-of-order expansion (bug present since
33 2.50); it now issues a syntax warning, and duplicates the expansion
34 of the inner macro to guarantee dependencies have been met. See
35 the manual for advice on how to refactor macros in order to avoid
36 the bug in earlier autoconf versions and avoid increased script
37 size in the current version.
39 ** AC_DEFUN_ONCE has improved semantics. Previously, a macro declared
40 with AC_DEFUN_ONCE warned on a second invocation; and out-of-order
41 expansion was still possible. Now, dependencies are guaranteed,
42 and subsequent invocations are a silent no-op. This makes
43 AC_DEFUN_ONCE an ideal macro for silencing AC_REQUIRE warnings.
45 ** The following macros are now defined with AC_DEFUN_ONCE. This means
46 a subtle change in semantics; previously, an AC_DEFUN macro could
47 expand one of these macros multiple times or surround the macro
48 inside shell conditional text to bypass the effects of these
49 macros, but now the macro will expand exactly once, and prior to
50 the start of any enclosing AC_DEFUN macro:
51 AC_CANONICAL_BUILD AC_CANONICAL_HOST AC_CANONICAL_TARGET
52 AC_HEADER_ASSERT AC_PROG_INSTALL AC_PROG_MKDIR_P
53 AC_USE_SYSTEM_EXTENSIONS
55 ** AC_LANG_ERLANG works once again (regression introduced in 2.61a).
57 ** AC_HEADER_ASSERT is fixed so that './configure --enable-assert' no
58 longer mistakenly disables assertions.
60 ** AC_INIT now takes an optional fifth parameter that can be used to
61 set AC_PACKAGE_URL, a URL for the package's home page; the URL is
62 used in `configure --help' and is also available via AC_DEFINE.
64 ** Autotest testsuites accept an option --jobs[=N] for parallel testing.
65 This feature is still in testing, and may not work on every
66 platform, help in improving it would be appreciated.
68 ** Autotest testsuites do not attempt to write startup error messages
69 to the log file before that is opened (regression introduced in 2.63).
71 ** Configure scripts now use shell functions. This feature leads to
72 smaller configure files and faster execution.
74 ** Present But Cannot Be Compiled: Autoconf will now proceed with
75 the compiler's result if a header is present but cannot be compiled.
76 The warning is still printed, and you should really fix it by
77 providing a fourth parameter to AC_CHECK_HEADER/AC_CHECK_HEADERS.
79 ** Autoreconf added aclocal to the set of programs affected by the
80 `autoreconf -I dir' option.
82 ** The following documented m4sugar macros are new:
83 m4_chomp m4_chomp_all m4_cleardivert m4_curry m4_default_quoted
84 m4_esyscmd_s m4_map_args m4_map_args_pair m4_map_args_sep
85 m4_map_args_w m4_set_map m4_set_map_sep m4_stack_foreach
86 m4_stack_foreach_lifo m4_stack_foreach_sep
87 m4_stack_foreach_sep_lifo
89 ** The following m4sugar macros are documented now, but in some cases
90 with slightly different semantics than what the previous
91 undocumented version had:
92 m4_copy m4_dumpdefs m4_rename m4_version_prereq
94 ** The m4sugar macro m4_expand has been taught to handle unterminated
95 comments and shell case statements. As a result, it is used
96 internally in more places, such as AC_DEFINE and AT_CHECK. Most
97 uses of AC_DEFINE and AT_CHECK should not behave any differently;
98 however, it may be necessary to add double-quoting around
99 unbalanced `(' where single-quoting used to be sufficient.
101 ** The following documented m4sh macros are new:
102 AS_INIT_GENERATED AS_LINENO_PREPARE AS_ME_PREPARE AS_SET_STATUS
103 AS_VAR_APPEND AS_VAR_ARITH AS_VAR_COPY
105 ** The following m4sh macros are documented now, but in some cases
106 with slightly different semantics than what the previous
107 undocumented version had:
108 AS_ECHO AS_ECHO_N AS_ESCAPE AS_EXIT AS_LITERAL_IF AS_UNSET
109 AS_VAR_IF AS_VAR_POPDEF AS_VAR_PUSHDEF AS_VAR_SET AS_VAR_SET_IF
110 AS_VAR_TEST_SET AS_VERSION_COMPARE
112 ** The m4sh macros AS_IF and AS_CASE can now be used in shell lists.
113 The responsibility for supplying a trailing newline now belongs to
114 the call site, but since most users did not add dnl, this generally
115 results in fewer empty lines in configure.
118 * Major changes in Autoconf 2.63 (2008-09-09) [stable]
119 Released by Eric Blake, based on git versions 2.62.*.
121 ** AC_C_BIGENDIAN does not mistakenly report "universal" for some
122 bigendian hosts, a regression introduced with universal binary
125 ** AC_PATH_X now includes /lib64 and /usr/lib64 in its list of default
128 ** AC_USE_SYSTEM_EXTENSIONS no longer conflicts with an external
129 AC_DEFINE([__EXTENSIONS__]). This fixes a regression introduced in
130 2.62 when using macros such as AC_AIX that were made obsolete in
131 favor of the more portable AC_USE_SYSTEM_EXTENSIONS.
133 ** AC_CHECK_TARGET_TOOLS is usable in the non-cross-compile case.
135 ** Newly obsolete macros
136 The following macro has been marked obsolete, since current porting
137 targets can safely assume C89 semantics that signal handlers return
138 void. We have no current plans to remove the macro.
142 ** The macros m4_map and m4_map_sep now ignore any list elements
143 consisting of just empty quotes, and m4_map_sep now expands its
144 separator. This fixes a regression in 2.62 when these macros were
145 first documented, for the sake of clients expecting the semantics
146 that these macros had prior to that time. The new macros m4_mapall
147 and m4_mapall_sep, along with extra quoting of the separator, can
148 be used to get the semantics that m4_map_sep had in 2.62.
150 ** Clients of m4_expand, such as AS_HELP_STRING and AT_SETUP, can now
151 handle properly quoted but otherwise unbalanced parentheses (for
152 some macros, this fixes a regression in 2.62).
154 ** Two new quadrigraphs have been introduced: @{:@ for (, and @:}@ for ),
155 allowing the output of unbalanced parentheses in more contexts.
157 ** The following m4sugar macros are new:
158 m4_cleardivert m4_joinall m4_mapall m4_mapall_sep m4_reverse
159 m4_set_add m4_set_add_all m4_set_contains m4_set_contents
160 m4_set_delete m4_set_difference m4_set_dump m4_set_empty
161 m4_set_foreach m4_set_intersection m4_set_list m4_set_listc
162 m4_set_remove m4_set_size m4_set_union
164 ** The following m4sugar macros now accept multiple arguments, as is the
165 case with underlying m4:
166 m4_defn m4_popdef m4_undefine
168 ** The following m4sugar macros now guarantee linear scaling; they
169 previously had linear scaling with m4 1.6 but quadratic scaling
170 when using m4 1.4.x. All macros built on top of these also gain
171 the scaling improvements.
172 m4_bmatch m4_bpatsubsts m4_case m4_cond m4_do m4_dquote_elt
173 m4_foreach m4_join m4_list_cmp m4_map m4_map_sep m4_max
176 ** AT_KEYWORDS once again performs expansion on its argument, such that
177 AT_KEYWORDS([m4_if([$1], [], [default])]) no longer complains about
178 the possibly unexpanded m4_if [regression introduced in 2.62].
180 ** Config header templates `#undef UNDEFINED /* comment */' do not lead to
181 nested comments any more; regression introduced in 2.62.
184 * Major changes in Autoconf 2.62 (2008-04-05) [stable]
185 Released by Eric Blake, based on git versions 2.61a.*.
187 ** Many optimizations have been applied to make overall execution faster.
189 ** Autotest now makes use of shell functions.
191 ** config.status now uses awk instead of sed also for config headers.
193 - As a side effect, AC_DEFINE and AC_DEFINE_UNQUOTED now handle multi-line
194 values, i.e., backslash-newline combinations are handled correctly.
195 Further, for config headers, the total size of values is not limited by
196 the POSIX length limit of text lines any more, only each single line.
198 ** New config variable `top_build_prefix'.
200 ** New Autoconf macros:
201 AC_AUTOCONF_VERSION AC_OPENMP AC_PATH_PROGS_FEATURE_CHECK
203 ** AC_C_BIGENDIAN now supports universal binaries a la Mac OS X.
205 ** AC_C_RESTRICT now prefers to #define 'restrict' to a variant spelling
206 like '__restrict' if the variant spelling is available, as this is
207 more likely to work when mixing C and C++ code.
209 ** AC_CHECK_ALIGNOF's type argument T is now documented better: it must
210 be a string of tokens such that "T y;" is a valid member declaration
213 ** AC_CHECK_SIZEOF now accepts objects as well as types: the general rule
214 is that sizeof (X) works, then AC_CHECK_SIZEOF (X) should work.
216 ** AC_CHECK_TYPE and AC_CHECK_TYPES now work on any C type-name; formerly,
217 they did not work for function types. In C++, they now work on any
218 type-id that can be the operand of sizeof; this is similar to C,
219 except it excludes anonymous struct and union types. Formerly,
220 some (but not all) C++ types involving anonymous struct and union
221 were accepted, though this was not documented.
223 ** AC_CONFIG_LINKS now prefers to link against files in the build tree
224 if found, and it works to link against a file of the same name in
225 the source tree, even if both trees coincide.
227 ** AC_INIT no longer alters $@; regression introduced in 2.60.
229 ** AC_USE_SYSTEM_EXTENSIONS now defines _ALL_SOURCE for Interix platforms.
231 ** AS_HELP_STRING no longer underquotes its first argument; it also handles
232 the case where the first argument contains single-quoted commas.
233 For example, "AS_HELP_STRING([-a, [--arg[=foo]]], [bar])" produces:
234 " -a, --arg[=foo] bar"
235 Additionally, the macro now takes two additional arguments,
236 indent-column and wrap-column; these should not normally be needed,
237 but can be used to fine-tune how the output text is wrapped.
239 ** AC_PROG_INSTALL now requires an install program that can install multiple
240 files into a target directory.
242 ** The command 'autoconf -' now correctly processes a file from stdin.
244 ** 'autoreconf -m' now honors $MAKE.
246 ** For all of the directory arguments for 'configure', such as '--prefix'
247 or '--bindir', trailing slashes are stripped. As an example, if
248 tab completion in the user's shell appends trailing slashes, the
249 command './configure --prefix=/usr/' will still result in an
250 expanded libdir value of /usr/lib, not /usr//lib.
252 ** `configure --help=recursive' now works in read-only trees and from
253 unconfigured build trees.
255 ** If precious variables differ only in whitespace, then the cache consistency
256 check warns instead of fails, and reuses the old value.
258 ** AT_BANNER is now documented.
260 ** AT_SETUP now handles macro expansions properly when calculating line
263 ** Autotest now determines $srcdir correctly.
265 ** Testsuites built by autotest now accept a -C/--directory=DIR option
266 to adjust the working directory prior to creating files.
268 ** Autoconf now requires GNU M4 1.4.5 or later. Earlier versions of M4 have
269 a bug in macro tracing that interferes with the interaction between
270 Autoconf and Automake. GNU M4 1.4.11 or later is recommended. The
271 configure search for a working M4 is improved.
273 ** For portability with the eventual M4 2.0, macros should no longer use
274 anything larger than $9 to refer to arguments.
276 ** Documentation for m4sugar is improved.
278 - The following macros were previously available as undocumented
279 interfaces; the macros are now documented as stable interfaces.
281 __oline__ m4_assert m4_bmatch m4_bpatsubsts m4_car m4_case
282 m4_cdr m4_default m4_divert_once m4_divert_pop m4_divert_push
283 m4_divert_text m4_do m4_errprintn m4_fatal m4_flatten
284 m4_ifndef m4_ifset m4_ifval m4_ifvaln m4_location
285 m4_n m4_shiftn m4_strip m4_warn
287 - The following macros were previously available as undocumented
288 interfaces, but had bug fixes or semantic changes as part of this
289 release. Packages that relied on the undocumented behavior
290 should be analyzed to make sure they will still work with the
291 new documented behavior.
293 m4_cmp m4_list_cmp m4_join m4_map m4_map_sep m4_sign
294 m4_text_box m4_text_wrap m4_version_compare
296 - The m4_wrap macro used to have unspecified order, but now
297 guarantees FIFO order. m4_wrap_lifo was added to guarantee LIFO
300 - Packages using the undocumented m4sugar macro m4_PACKAGE_VERSION
301 should consider using the new AC_AUTOCONF_VERSION instead.
303 - m4sugar macros that are not documented in the manual are still
304 deemed experimental, and should not be used outside of Autoconf.
306 ** The m4sugar macros m4_append and m4_append_uniq, first documented in
307 2.60, have been fixed to treat both the string and the separator
308 arguments consistently with regards to quoting. Prior to this fix,
309 m4_append_uniq could mistakenly duplicate entries if the expansion
310 of the separator resulted in a different string (for example, if it
311 contained quotes, a comma, or a macro name). However, it means
312 that programs previously using
313 m4_append([name], [string], [[, ]])
314 are now using a four-character separator instead of the intended
315 comma and space. If you need portability to earlier versions of
316 Autoconf, you can insert the following snippet after AC_INIT but
317 before any other macro expansions, to enforce the new semantics:
318 m4_pushdef([m4_append], [m4_define([$1],
319 m4_ifdef([$1], [m4_defn([$1])[$3]])[$2])])
320 Additionally, m4_append_uniq now takes optional parameters that can
321 be used to take action depending on whether anything was appended,
322 and warns if a non-empty separator occurs within the string being
323 appended, since that can lead to duplicates.
325 ** The following m4sugar macros are new:
326 m4_append_uniq_w m4_apply m4_combine m4_cond m4_count
327 m4_dquote_elt m4_echo m4_expand m4_ignore m4_make_list m4_max
328 m4_min m4_newline m4_shift2 m4_shift3 m4_unquote m4_wrap_lifo
330 ** Warnings are now generated by default when an installer invokes
331 'configure' with an unknown --enable-* or --with-* option.
332 These warnings can be disabled with the new AC_DISABLE_OPTION_CHECKING
333 macro, or by invoking 'configure' with --disable-option-checking.
335 ** Existing obsolete macros
336 The documentation for the following macros is adjusted to make it
337 more clear that they have previously been marked obsolete, as their
338 functionality can be accomplished by other macros. We have no
339 current plans to remove them from Autoconf.
341 AC_ENABLE AC_STRUCT_ST_BLKSIZE AC_STRUCT_ST_RDEV AC_WITH
343 ** Newly obsolete macros
344 The following macros have been marked obsolete, as they only
345 perform a subset of AC_USE_SYSTEM_EXTENSIONS. We have no current
346 plans to remove them.
348 AC_AIX AC_GNU_SOURCE AC_ISC_POSIX AC_MINIX
350 ** AC_C_LONG_DOUBLE is obsolescent.
351 The documentation now says that AC_C_LONG_DOUBLE is obsolescent: it
352 tests for problems that are so old that it is no longer of
353 practical importance on current systems. New programs need not use
354 AC_C_LONG_DOUBLE. We have no current plans to remove it.
356 ** AC_DIAGNOSE, AC_WARNING, and AC_FATAL are obsolescent.
357 The documentation now favors the use of M4sugar macros m4_warn and
358 m4_fatal, since the naming makes it more obvious that the
359 diagnostics are associated with M4 expansion (ie. when running
360 `autoconf'), and offers less confusion with the AC_MSG_ERROR,
361 AC_MSG_FAILURE, and AC_MSG_WARN macros which manage diagnostics
362 when running `configure'. We have no current plans to remove these
366 * Major changes in Autoconf 2.61a (2006-12-11)
368 ** AC_FUNC_FSEEKO was broken in 2.61; it didn't make fseeko and ftello visible
369 on many platforms. This has been fixed.
371 ** AC_FUNC_SETVBUF_REVERSED is now obsolete. It is still defined for backward
372 compatibility but it does nothing. The macro was already
373 obsolescent, as the last systems to have the problem were those
374 based on SVR2, which became obsolete in 1987. The macro had bugs
375 on some modern systems and could no longer be maintained reliably
376 due to lack of ancient systems to test it on.
378 ** config.status now uses awk instead of sed for most substitutions, for speed.
380 - As a side effect multi-line values of substituted variables no
381 longer have a small limit in total size, though for portability
382 each line should not exceed the POSIX length limit for text lines.
384 - It is now documented that Makefile.in should not contain
385 overlapping variable occurrences, e.g., @VAR1@VAR2@.
386 Autoconf's behavior was always iffy in such cases, and the
387 awk implementation has changed the behavior.
389 ** Many uses of 'echo' have been rewritten so that Autoconf-generated
390 scripts have fewer problems with strings or file names containing
391 embedded special characters such as backslash or leading "-". This
392 was implemented by using `printf '%s\n' "$foo"' instead of `echo
393 "$foo"' when printf works. Due to the implementation technique
394 used, Autoconf-generated scripts now run considerably more slowly
395 on ancient implementations lacking printf. However, this should
396 not be a problem, since Autoconf-generated scripts in practice
397 invariably find a more-modern shell these days.
400 * Major changes in Autoconf 2.61 (2006-11-17)
402 ** New macros AC_C_FLEXIBLE_ARRAY_MEMBER, AC_C_VARARRAYS.
404 ** AC_ARG_ENABLE and AC_ARG_WITH now allow '.' in feature and package names.
407 * Major changes in Autoconf 2.60b (2006-10-22)
410 Autoconf-generated shell scripts no longer export BIN_SH, due to
411 configuration hassles with this. Installers who need BIN_SH in
412 their environment should set it before invoking 'configure' and
413 'make'. As far as we know, this affects only Unixware installations.
415 ** Obsolescent macros
416 The documentation now says that the following macros are obsolescent,
417 as they are superseded by Gnulib:
419 AC_FUNC_FNMATCH AC_FUNC_FNMATCH_GNU AC_FUNC_GETLOADVG AC_REPLACE_FNMATCH
421 New programs should use the Gnulib counterparts of these macros.
422 We have no current plans to remove them from Autoconf.
424 ** AC_COMPUTE_INT no longer caches or reports results.
426 ** AC_CHECK_DECL now also works with aggregate objects.
428 ** AC_USE_SYSTEM_EXTENSIONS now defines _TANDEM_SOURCE for NonStop platforms.
430 ** GNU M4 1.4.7 or later is now recommended.
433 New M4sugar macro, which is more secure than the POSIX M4 maketemp.
436 Now an alias for m4_mkstemp.
438 * Major changes in Autoconf 2.60a (2006-08-25)
440 ** GNU M4 1.4.6 or later is now recommended.
442 ** The check for C99 now tests for varargs macros, as documented.
443 It also tests that the preprocessor supports 64-bit integers.
445 ** Autoconf now uses constructs like "#ifdef HAVE_STDLIB_H" rather than
446 "#if HAVE_STDLIB_H", so that it now works with "gcc -Wundef -Werror".
448 ** The functionality of the undocumented _AC_COMPUTE_INT is now provided
449 by a public and documented macro, AC_COMPUTE_INT. The parameters to the
450 two macros are different, so autoupdate will not change the old private name
451 to the new one. _AC_COMPUTE_INT may be removed in a future release.
453 ** AC_TYPE_LONG_LONG_INT and AC_TYPE_UNSIGNED_LONG_LONG_INT now require
454 that long long types be at least 64 bits wide, as C99 and tradition
455 requires. Formerly, they accepted implementations of any width.
458 * Major changes in Autoconf 2.60
460 Released 2006-06-23, by Ralf Wildenhues.
462 ** Autoconf no longer depends on whether m4wrap is FIFO (as Posix requires)
463 or LIFO (as in GNU M4 1.4.x). GNU M4 2.0 is expected to conform to Posix
464 here, so m4wrap/m4_wrap users should no longer depend on LIFO behavior.
466 ** Provide a way to turn off warnings about the changed directory variables.
468 * Major changes in Autoconf 2.59d
470 Released 2006-06-05, by Ralf Wildenhues.
472 ** GNU make now recommended for VPATH builds
473 INSTALL now suggests VPATH builds (e.g., "sh ../srcdir/configure")
474 only if you use GNU make. In practice, other 'make' implementations
475 have too many subtle incompatibilities in their support for VPATH.
476 Many packages (including Autoconf itself) are portable to other
477 'make' implementations, but some packages are not, and recommending
478 GNU make keeps the installation instructions simpler.
480 ** Even more safety checks for the new Directory variables:
481 Warn about suspicious `${datarootdir}' found in config files output.
483 ** AC_TRY_COMMAND, AC_TRY_EVAL, ac_config_guess, ac_config_sub, ac_configure
484 These never-documented macros and variables have been marked with
485 comments saying that they may be removed in a future release,
486 because their use can lead to unintended code being executed.
487 If you need functionality that only these macros or variables
488 currently supply, please write bug-autoconf@gnu.org.
490 ** AC_SUBST, AC_DEFINE
491 Literal arguments to these are passed to m4_pattern_allow now.
494 Passing 'ac_cv_prog_cc_stdc=no' to 'configure' now sets ac_cv_prog_cc_c99
495 and ac_cv_prog_cc_c89 to 'no' as well, for backward compatibility with
496 obsolete K&R tests in the Automake test suite.
505 Now more robust with special characters in file names, or when
506 multiple processes create the same directory at the same time.
508 ** Obsolescent macros
509 The documentation now says that the following macros are obsolescent:
510 they test for problems that are so old that they are no longer of
511 practical importance on current systems.
513 AC_C_BACKSLASH_A AC_FUNC_MEMCMP AC_HEADER_DIRENT
514 AC_C_CONST AC_FUNC_SELECT_ARGTYPES AC_HEADER_STAT
515 AC_C_PROTOTYPES AC_FUNC_SETPGRP AC_HEADER_STDC
516 AC_C_STRINGIZE AC_FUNC_SETVBUF_REVERSED AC_HEADER_SYS_WAIT
517 AC_C_VOLATILE AC_FUNC_STAT AC_HEADER_TIME
518 AC_FUNC_CLOSEDIR_VOID AC_FUNC_STRFTIME AC_ISC_POSIX
519 AC_FUNC_GETPGRP AC_FUNC_UTIME_NULL AC_PROG_GCC_TRADITIONAL
520 AC_FUNC_LSTAT AC_FUNC_VPRINTF AC_STRUCT_TM
522 New programs need not use these macros. We have no current plans to
526 For compatibility with future Libtool 2.0, autoreconf will invoke
527 libtoolize with the option `--ltdl' now, if LT_CONFIG_LTDL_DIR is
530 * Major changes in Autoconf 2.59c
532 Released 2006-04-12, by Ralf Wildenhues.
534 ** The configure command now redirects standard input from /dev/null,
535 to help avoid problems with subsidiary commands that might mistakenly
536 read standard input. AS_ORIGINAL_STDIN_FD points to the original
537 standard input before this redirection, if you really want configure to
538 read from standard input.
540 ** Directory variables adjusted to recent changes in the GNU Coding Standards.
541 The following directory variables are new:
543 datarootdir read-only architecture-independent data root [PREFIX/share]
544 localedir locale-specific message catalogs [DATAROOTDIR/locale]
545 docdir documentation root [DATAROOTDIR/doc/PACKAGE]
546 htmldir html documentation [DOCDIR]
547 dvidir dvi documentation [DOCDIR]
548 pdfdir pdf documentation [DOCDIR]
549 psdir ps documentation [DOCDIR]
551 The following variables have new default values:
553 datadir read-only architecture-independent data [DATAROOTDIR]
554 infodir info documentation [DATAROOTDIR/info]
555 mandir man documentation [DATAROOTDIR/man]
557 This means that if you use any of `@datadir@', `@infodir@', or
558 `@mandir@' in a file, you will have to ensure `${datarootdir}' is
559 defined in this file. As a temporary measure, if any of those are
560 found but no mention of `datarootdir', the substitutions will be
561 replaced with values that do not contain `${datarootdir}', and a
562 warning will be issued.
564 ** @top_builddir@ is now a dir name: it is always nonempty and doesn't have
565 a trailing slash. Similar change will be made to ac_top_builddir in a
566 future release; the old style value, which matches (../)*, is (and will
567 continue to be) available as ac_top_build_prefix.
570 New macro to check for support of 'typeof' syntax a la GNU C.
572 ** AC_CHECK_DECLS_ONCE, AC_CHECK_FUNCS_ONCE, AC_CHECK_HEADERS_ONCE
573 New "once-only" variants of commonly-used macros, to make 'configure'
574 smaller and faster in common cases.
577 New macro to check for strtold with C99 semantics.
580 New macro that lets builder disable assertions at 'configure'-time.
583 Now checks for X11/Xlib.h and XrmInitialize (X proper) rather than
584 X11/Intrinsic.h and XtMalloc (Xt).
586 ** AC_PRESERVE_HELP_ORDER
587 New macro that causes `configure' to display help strings for AC_ARG_ENABLE
588 and AC_ARG_WITH arguments in one region, in the order defined. The default
589 behavior is to group options of each classes separately.
591 ** AC_PROG_CC, AC_PROG_CXX
592 No longer automatically arrange to declare the 'exit' function of C,
593 when a C++ compiler is used. Standard Autoconf macros no longer use
594 'exit', so this is no longer an issue for them. If you use C++, and
595 want to call 'exit', you'll have to arrange for its declaration
596 yourself. But we now suggest you return from 'main' instead.
598 ** AC_PROG_CC_C89, AC_PROG_CC_C99
599 New macros for ISO C99 support. AC_PROG_CC_C89 and AC_PROG_CC_C99
600 check for ANSI C89 and ISO C99 support respectively.
603 Has been unobsoleted, and will check if the compiler supports ISO
604 C99, falling back to ANSI C89 if not. ac_cv_prog_cc_stdc is
605 retained for backwards compatibility, assuming the value of
606 ac_cv_prog_cc_c99 or ac_cv_prog_cc_c89 (whichever is valid, in
609 ** AC_STRUCT_DIRENT_D_INO, AC_STRUCT_DIRENT_D_TYPE
610 New macros for checking commonly-used members of struct dirent.
613 The substituted value can now contain newlines.
616 The substitution now occurs only when @variable@ is on a line by itself,
617 optionally surrounded by spaces and tabs. The whole line is replaced.
619 ** AC_TYPE_LONG_DOUBLE, AC_TYPE_LONG_DOUBLE_WIDER
620 New macros to check for long double, and whether it is wider than double.
621 The old macro AC_C_TYPE_LONG_DOUBLE has been marked as obsolete;
622 applications should switch to the new macro.
624 ** AC_TYPE_INT8_T, AC_TYPE_INT16_T, AC_TYPE_INT32_T, AC_TYPE_INT64_T,
625 AC_TYPE_INTMAX_T, AC_TYPE_INTPTR_T, AC_TYPE_LONG_LONG_INT, AC_TYPE_SSIZE_T,
626 AC_TYPE_UINT8_T, AC_TYPE_UINT16_T, AC_TYPE_UINT32_T, AC_TYPE_UINT64_T,
627 AC_TYPE_UINTMAX_T, AC_TYPE_UINTPTR_T, AC_TYPE_UNSIGNED_LONG_LONG_INT
628 New macros to check for C99 and POSIX types.
630 ** AC_USE_SYSTEM_EXTENSIONS
631 New macro to enable extensions to Posix.
634 New macro which is defined to the name of the first declared config header
635 or undefined if no config headers have been declared yet.
638 The macro correctly handles quadrigraphs now.
640 ** AS_BOURNE_COMPATIBLE, AS_SHELL_SANITIZE, AS_CASE
641 These macros are new or published now.
644 New macro for copyright notices in testsuite files.
646 ** ALLOCA, LIBOBJS, LTLIBOBJS
647 Object names added to these variables are now prefixed with `${LIBOBJDIR}',
648 as in `${LIBOBJDIR}alloca.o'. LIBOBJDIR is meant to be defined from
649 `Makefile.in' in case the object files lie in a different directory.
650 The LIBOBJDIR feature is experimental.
653 Supports --no-recursive now.
655 ** New macros to support Erlang/OTP.
656 New macros for configuring paths to Erlang tools and libraries:
657 AC_ERLANG_PATH_ERLC, AC_ERLANG_NEED_ERLC, AC_ERLANG_PATH_ERL,
658 AC_ERLANG_NEED_ERL, AC_ERLANG_CHECK_LIB, AC_ERLANG_SUBST_ROOT_DIR,
659 AC_ERLANG_SUBST_LIB_DIR.
661 New macros for configuring installation of Erlang libraries:
662 AC_ERLANG_SUBST_INSTALL_LIB_DIR, AC_ERLANG_SUBST_INSTALL_LIB_SUBDIR.
664 ** The manual now mentions Gnulib more prominently.
666 ** New macros to support Objective C.
667 AC_PROG_OBJC, AC_PROG_OBJCPP.
669 * Major changes in Autoconf 2.59b
671 Released 2004-08-20, by Paul Eggert.
674 New macro that computes the default alignment of a type.
676 ** AC_CHECK_TOOL, AC_PATH_TOOL, AC_CHECK_TOOLS
677 When cross-compiling, these macros will give a warning if the tool
678 is not prefixed. In the future, unprefixed cross tools will not
679 be detected; please consult the info documentation for information
680 about the reason of this change.
682 ** AC_CHECK_TARGET_TOOL, AC_PATH_TARGET_TOOL, AC_CHECK_TARGET_TOOLS
683 New macros that detect programs whose name is prefixed with the
684 target type, if the build type and target type are different.
686 ** AC_REQUIRE_AUX_FILE
687 New trace macro that declares expected auxiliary files.
690 New macro that tests for a grep program that accepts as a long a line
693 ** AC_PROG_EGREP, AC_PROG_FGREP
694 These macros now require AC_PROG_GREP, and try EGREP="$GREP -E" and
695 FGREP="$GREP -F" respectively if possible, or else run a path search for
696 a program that accepts as long a line as possible.
699 New macro that tests for a sed program that truncates as few characters
702 * Major changes in Autoconf 2.59
704 Released 2003-11-04, by Akim Demaille
706 ** ac_abs_builddir etc.
707 Absolute file names were actually relative in 2.58.
709 * Major changes in Autoconf 2.58
711 Released 2003-11-04, by Akim Demaille
714 core.* files are no longer removed, as they may be valid user files.
716 ** autoreconf and auxiliary directory
717 Autoreconf creates the auxiliary directory if needed. This is
718 especially useful for initial "bootstrapping" of fresh CVS checkouts.
720 ** AC_CONFIG_MACRO_DIR
721 Use this macro to declare the directory for local M4 macros for aclocal.
724 No longer includes twice the same file in LIBOBJS if invoked
727 ** AC_CONFIG_COMMANDS
728 The directory for its first argument is automatically created. For
731 AC_CONFIG_COMMANDS([src/modules.hh], [...])
733 $top_builddir/src/ is created if needed.
735 ** Autotest and local.at
736 The optional file local.at is always included in Autotest test suites.
739 The warnings are always issued, including with cached runs.
740 This became a significant problem since aclocal and automake can
741 run autoconf behind the scene.
743 ** autoheader warnings
744 The warnings of autoheader can be turned off, using --warning.
745 For instance, -Wno-obsolete disables the complaints about acconfig.h
746 and other deprecated constructs.
749 AC_C_RESTRICT, AC_INCLUDES_DEFAULT, AC_LANG_ASSERT, AC_LANG_WERROR,
752 ** AC_DECL_SYS_SIGLIST
756 Now checks that mktime is the inverse of localtime.
758 ** Improve DJGPP portability
759 The Autoconf tools and configure behave better under DJGPP.
761 ** Present But Cannot Be Compiled
762 New FAQ section dedicated to the mystic
764 configure: WARNING: pi.h: present but cannot be compiled
765 configure: WARNING: pi.h: check for missing prerequisite headers?
766 configure: WARNING: pi.h: proceeding with the preprocessor's result
769 ** Concurrent executions of autom4te
770 autom4te now locks its internal files, which enables concurrent
771 executions of autom4te, likely to happen if automake, autoconf,
772 autoheader etc. are run simultaneously.
775 Use of Libtool 1.5 and higher is encouraged. Compatibility with
776 Libtool pre-1.4 is not checked.
779 Testsuites no longer rerun failed tests in verbose mode; instead,
780 failures are logged while the test is run.
782 In addition, expected failures can be marked as such.
784 * Major changes in Autoconf 2.57
786 Released 2002-12-03 by Paul Eggert.
788 Bug fixes for problems with AIX linker, with freestanding C compilers,
789 with GNU M4 limitations, and with obsolete copies of GNU documents.
791 The Free Documentation License has been upgraded from 1.1 to 1.2.
793 * Major changes in Autoconf 2.56
795 Released 2002-11-15 by Akim Demaille.
797 One packaging problem fixed (config/install-sh was not executable).
799 * Major changes in Autoconf 2.55
801 Released 2002-11-14 by Akim Demaille.
805 Have your configure.ac checked by autoscan ("autoscan").
806 Try the warning options ("autoreconf -fv -Wall").
810 - AC_CHECK_HEADER, AC_CHECK_HEADERS
811 More information on proper use.
813 - Writing Test Programs
815 This sections explains how to write good test sources to use with
816 AC_COMPILE_IFELSE etc. It documents AC_LANG_PROGRAM and so forth.
818 - AC_FOO_IFELSE vs. AC_TRY_FOO
820 Explains why Autoconf moves from AC_TRY_COMPILE etc. to
821 AC_COMPILE_IFELSE and AC_LANG_PROGRAM etc.
825 - Is more robust to different Gettext installations.
827 - Produces messages (when --verbose) to be understood by Emacs'
830 - Supports -W/--warnings.
833 Once the GNU Build System reinstalled, run `./config.status
834 --recheck && ./config.status && make' if possible.
838 - Supports --cache, and --no-cache.
840 - ~/.autom4te.cfg makes it possible to disable the caching mechanism
841 (autom4te.cache). See `Customizing autom4te' in the documentation.
848 Support for the obsoleted options -m, --macrodir, -l, --localdir is
849 dropped in favor of the safer --include/--prepend-include scheme.
854 AC_COMPILER_IFELSE, AC_FUNC_MBRTOWC, AC_HEADER_STDBOOL,
855 AC_LANG_CONFTEST, AC_LANG_SOURCE, AC_LANG_PROGRAM, AC_LANG_CALL,
856 AC_LANG_FUNC_TRY_LINK, AC_MSG_FAILURE, AC_PREPROC_IFELSE.
859 Obsoleted macros are kept for Autoconf backward compatibility, but
860 should be avoided in configure.ac. Running autoupdate is advised.
863 - AC_DEFINE/AC_DEFINE_UNQUOTED
865 We have to stop using the old compatibility scheme --that tried to
866 avoid useless backslashes-- because Libtool 1.4.3 contains a
868 AC_DEFINE([error_t], [int],
869 [Define to a type to use for \`error_t' if it is not
870 otherwise available.])
872 We have to quote the single quotes and backslashes with \. The old
873 compatibility scheme saw that ` was backslashed, and therefore did
874 not quote the single quote... Failure. Hence, Autoconf 2.54 is not
875 compatible with Libtool. Autoconf 2.55 is, but in some cases might
876 produce more \ than wanted.
878 Please, note that in the future the same problem will happen with
879 AC_MSG_*: use `autoreconf -f -Wall'.
883 - Portability of the Autoconf package to Solaris.
885 - Spurious warnings caused by config.status.
886 This bug is benign, but painful: on some systems (typically
887 FreeBSD), warnings such as:
889 config.status: creating Makefile
890 mv: Makefile: set owner/group (was: 1357/0): Operation not permitted
892 could be issued. This is fixed.
895 Simultaneous executions of config.status are possible again.
897 - Precious variables accumulation
899 config.status could stack several copies of the precious variables
903 ** Plans for later versions
907 The compatibility hooks with the old scheme will be completely
908 removed. Please, advice/use `--build', `--host', and `--target'
911 - AC_CHECK_HEADER, AC_CHECK_HEADERS
913 The tests will be stricter, please make sure your invocations are
918 Shell functions will gradually be introduced, probably starting with
919 Autotest. If you know machines which are in use that you suspect
920 *not* to support shell functions, please run the test suite of
921 Autoconf 2.55 on it, and report the results to
922 bug-autoconf@gnu.org.
926 Special characters in AC_MSG_* need not be quoted. Currently,
927 Autoconf has heuristics to decide when a string is escaped, or has
928 to be escaped. This scheme is fragile, and will be removed; the
929 only risk is uglified messages. Please, run `autoreconf -f -Wall'
930 to find occurrences that will be affected.
932 * Major changes in Autoconf 2.54
934 Released 2002-09-13 by Akim Demaille.
938 - autoreconf no longer changes the version of the gettext/po/intl
939 support files. It now adds the files the correspond to the
940 AM_GNU_GETTEXT_VERSION declared in configure.ac.
942 Warning: It now relies on the 'autopoint' program, which is part
943 of GNU gettext 0.11.4 and newer.
945 Please note that you need to have a GNU gettext version that
946 corresponds at least to the AM_GNU_GETTEXT_VERSION declared
947 in configure.ac. You can upgrade to newer GNU gettext versions,
948 though, without needing to change configure.ac.
950 - The -I DIR or --include=DIR option now appends DIR to the include path
951 instead of prepending; this is for consistency with other GNU tools.
952 The new -B DIR or --prepend-include=DIR option has the old behavior.
957 Now handles all the gory details about LIBOBJS and LTLIBOBJS.
958 Please, remove lines such as
960 # This is necessary so that .o files in LIBOBJS are also
961 # built via the ANSI2KNR-filtering rules.
962 LIBOBJS=`echo $LIBOBJS|sed 's/\.o /\$U.o /g;s/\.o$/\$U.o/'`
964 and read the `AC_LIBOBJ vs LIBOBJS' section. Do not define U in
965 your Makefiles either.
967 - AC_CONFIG_LINKS now makes copies if it can't make links.
969 - AC_FUNC_FNMATCH now tests only for POSIX compatibility, reverting to
970 Autoconf 2.13 behavior. The new macro AC_FUNC_FNMATCH_GNU also
971 tests for GNU extensions to fnmatch, and replaces fnmatch if needed.
973 - AC_FUNC_SETVBUF_REVERSED no longer fails when cross-compiling.
975 - AC_PROG_CC_STDC is integrated into AC_PROG_CC.
977 - AC_PROG_F77 default search no longer includes cf77 and cfg77.
981 AC_C_BACKSLASH_A, AC_CONFIG_LIBOBJ_DIR, AC_GNU_SOURCE,
982 AC_PROG_EGREP, AC_PROG_FGREP, AC_REPLACE_FNMATCH,
983 AC_FUNC_FNMATCH_GNU, AC_FUNC_REALLOC, AC_TYPE_MBSTATE_T.
986 looks for getloadavg.c in the CONFIG_LIBOBJ_DIR.
989 Now defines HAVE_MALLOC to 0 if `malloc' does not work, and asks
990 for an AC_LIBOBJ replacement.
994 - Spurious complaints from `m4_bmatch' about invalid regular
995 expressions are suppressed.
997 - Empty top_builddirs are properly handled.
999 - AC_CHECK_MEMBER works correctly when the member is an aggregate.
1002 Now colon in the optional path arguments are properly handled.
1004 ** Improved portability
1006 - Both Autoconf the package, and the scripts it produces, should run
1007 more reliably with Zsh. Bear in mind it is the default Bourne shell
1010 - Autoconf and the scripts it produces no longer assume the existence of
1011 the obsolescent commands egrep and fgrep.
1015 - Limitations of Make
1019 The GNATS base moved to
1020 http://bugs.gnu.org/cgi-bin/gnatsweb.pl?database=autoconf
1021 (It is no longer available, though.)
1026 Now contains the list of ouput variables and files (AC_SUBST,
1029 * Major changes in Autoconf 2.53
1031 Released 2002-03-08 by Akim Demaille.
1035 Perl 5.005_03 or later is required: autom4te is written in Perl and is
1036 needed by autoconf. autoheader, autoreconf, ifnames, and autoscan are
1042 Argument requirements, output variables, defined macros.
1043 - M4sugar, M4sh, Autotest
1045 - Double quoting macros
1046 AC_TRY_CPP, AC_TRY_COMPILE, AC_TRY_LINK and AC_TRY_RUN.
1048 The Autoconf manual is now distributed under the terms of the GNU FDL.
1049 - Section `Hosts and Cross-Compilation'
1050 Explains the rationale for the 2.5x changes in the cross-compilation
1051 chain, and in the relationships between build, host, and target
1053 Emphasizes that `cross-compilation' == `--host is given'.
1054 If you are working on compilers etc., be sure to read this section.
1055 - Section `AC_LIBOBJ vs. LIBOBJS'
1056 Explains why assigning LIBOBJS directly is now an error.
1057 Details how to update the code.
1062 Now used instead of hard coded line numbers.
1063 This eases the comparison of `configure's, and diminishes the
1064 pressure over control version archives.
1065 Automatic replacement for shells that don't support this feature.
1066 - New output variables
1067 @builddir@, @top_builddir@, @abs_srcdir@, @abs_top_srcdir@, @abs_builddir@,
1072 Autoconf and Autotest modes are provided.
1077 New, used by the Autoconf suite to cache and speed up most processing.
1079 Supported by autom4te, autoconf and autoheader.
1081 Replaces --autoconf-dir and --localdir in autoconf, autoheader,
1082 autoupdate, and autoreconf.
1084 No longer passes --cygnus, --foreign, --gnits, --gnu, --include-deps:
1085 automake options are to be given via AUTOMAKE_OPTIONS.
1087 Runs gettextize and libtoolize when appropriate.
1089 --m4dir is no longer supported.
1091 Now runs only in the specified directories, defaulting to `.',
1092 but understands AC_CONFIG_SUBDIRS for dependent directories.
1093 Before, it used to run on all the `configure.ac' found in the
1095 Independent packages are properly updated.
1099 - The top level $prefix is propagated to the AC_CONFIG_SUBDIRS configures.
1101 Under the user pressure, $? is finally available. Probably a mistake.
1102 - AC_F77_LIBRARY_LDFLAGS now supports the HP/UX f90 compiler.
1103 - Precious variables accumulation
1104 config.status could stack several copies of the precious variables
1106 - AC_PATH_PROG and family.
1107 Works properly when given a literal path.
1109 Somewhere since 2.13, the result had been reversed.
1113 - AC_C_BIGENDIAN supports the cross-compiling case.
1114 - AC_C_BIGENDIAN accepts ACTION-IF-TRUE, ACTION-IF-FALSE, and
1115 ACTION-IF-UNKNOWN arguments. All are facultative, and the default
1116 for ACTION-IF-TRUE is to define WORDS_BIGENDIAN like AC_C_BIGENDIAN
1118 - AC_C_LONG_DOUBLE now succeeds only if `long double' has more range or
1119 precision than `double'.
1124 It now defines the preprocessor symbols PACKAGE_NAME,
1125 PACKAGE_TARNAME, PACKAGE_VERSION, PACKAGE_STRING, and
1129 Admits a fourth optional parameter: the tar name.
1131 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS.
1132 Provide the user with srcdir, ac_srcdir, ac_top_srcdir, ac_builddir,
1133 ac_top_builddir, ac_abs_srcdir, ac_abs_top_srcdir, ac_abs_builddir,
1134 ac_abs_top_builddir.
1136 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS and AC_OUTPUT.
1137 Are much less expensive when using long lists of files.
1140 Works with shell variables, and non alphanumeric names.
1144 - AC_FUNC_STRERROR_R now sets STRERROR_R_CHAR_P, not HAVE_WORKING_STRERROR_R,
1145 because POSIX 1003.1-200x draft 7 says strerror_r returns int, not char *.
1147 - AC_FUNC_STRTOD substitutes POW_LIB.
1152 * Major changes in Autoconf 2.52
1154 Released 2001-07-18 by Akim Demaille.
1159 This feature was present in autoconf 2.50 but was not documented.
1160 For example, `@<:@' is translated to `[' just before output. This
1161 is useful when writing strings that contain unbalanced quotes, or
1162 other hard-to-quote constructs.
1163 - m4_pattern_forbid, m4_pattern_allow
1164 - Tips for upgrading from 2.13.
1165 - Using autoscan to maintain a configure.ac.
1168 - Now include stdint.h.
1169 - sys/types.h and sys/stat.h are guarded.
1170 - strings.h is included if available, and not conflicting with string.h.
1173 - The test suite is more robust and presents less false failures.
1174 - Invocation of GNU M4 now robust to POSIXLY_CORRECT.
1175 - configure accepts --prefix='' again.
1176 - AC_CHECK_LIB works properly when its first argument is not a
1178 - HAVE_INTTYPES_H is defined only if not conflicting with sys/types.h.
1179 - build_, host_, and target_alias are AC_SUBST as in 2.13.
1180 - AC_ARG_VAR properly propagates precious variables inherited from the
1181 environment to ./config.status.
1182 - Using --program-suffix/--program-prefix is portable.
1183 - Failures to detect the default compiler's output extension are less
1185 - `config.status foo' works properly when `foo' depends on variables
1186 set in an AC_CONFIG_THING INIT-CMD.
1187 - autoheader is more robust to broken input.
1188 - Fixed Fortran name-mangling and link tests on a number of systems,
1189 e.g. NetBSD; see AC_F77_DUMMY_MAIN, below.
1192 - AC_CHECK_HEADER and AC_CHECK_HEADERS support a fourth argument to
1193 specify pre-includes. In this case, the headers are compiled with
1194 cc, not merely preprocessed by cpp. Therefore it is the _usability_
1195 of a header which is checked for, not just its availability.
1196 - AC_ARG_VAR refuses to run configure when precious variables have
1198 - Versions of compilers are dumped in the logs.
1199 - AC_CHECK_TYPE recognizes use of `foo_t' as a replacement type.
1202 - AC_PATH_XTRA only adds -ldnet to $LIBS if it's needed to link.
1203 - AC_FUNC_WAIT3 and AC_SYS_RESTARTABLE_SYSCALLS are obsoleted.
1204 - AM_FUNC_ERROR_AT_LINE, AM_FUNC_FNMATCH, AM_FUNC_MKTIME,
1205 AM_FUNC_OBSTACK, and AM_FUNC_STRTOD are now activated.
1206 Be sure to read `Upgrading from Version 2.13' to understand why
1207 running `autoupdate' is needed.
1208 - AC_F77_DUMMY_MAIN, AC_F77_MAIN: new macros to detect whether
1209 a main-like routine is required/possible when linking C/C++ with
1210 Fortran. Users of e.g. AC_F77_WRAPPERS should be aware of these.
1211 - AC_FUNC_GETPGRG behaves better when cross-compiling.
1213 * Major changes in Autoconf 2.51
1214 There was no release of Autoconf 2.51 since some packagers had used
1215 this version number without permission to ship intermediary versions
1216 of 2.50. The version was skipped to avoid confusion.
1218 * Major changes in Autoconf 2.50
1220 Released 2001-05-21 by Akim Demaille.
1222 ** Lots of bug fixes
1223 There have been far too many to enumerate them here. Check out
1224 ChangeLog if you really want to know more.
1226 ** Improved documentation
1227 In particular, portability issues are better covered.
1230 All the standard GNU Makefile targets are supported. The layout has
1231 changed: m4/ holds the M4 extensions Autoconf needs for its
1232 configuration, doc/ contains the documentation, and tests/ contains
1235 ** Man pages are provided
1236 For autoconf, autoreconf, autoupdate, autoheader, autoscan, ifnames,
1237 config.guess, config.sub.
1241 Provides a safe and powerful means to trace the macro uses. This
1242 provide the parsing layer for tools which need to `study'
1246 Specify what category of warnings should be enabled.
1248 - When recursing into subdirectories, try for configure.gnu before
1249 configure to adapt for packages not using autoconf on case-insensitive
1253 More errors are now caught (circular AC_REQUIRE dependencies,
1254 AC_DEFINE in the action part of an AC_CACHE_CHECK, too many pops
1255 etc.). In addition, their location and call stack are given.
1258 autoupdate is much more powerful, and is able to provide the glue code
1259 which might be needed to move from an old macro to its newer
1262 You are strongly encouraged to use it to modernize both your
1263 `configure.in' and your .m4 extension files.
1266 The internal machinery of autoheader has completely changed. As a
1267 result, using `acconfig.h' should be considered to be obsoleted, and
1268 you are encouraged to get rid of it using the AH macros.
1273 ** Fortran 77 compilers
1274 Globally, the support for Fortran 77 is considerably improved.
1276 Support for automatically determining a Fortran 77 compiler's
1277 name-mangling scheme. New CPP macros F77_FUNC and F77_FUNC_ are
1278 provided to wrap C/C++ identifiers, thus making it easier and more
1279 transparent for C/C++ to call Fortran 77 routines, and Fortran 77 to
1280 call C/C++ routines. See the Texinfo documentation for details.
1283 The test suite no longer uses DejaGNU. It should be easy to submit
1284 test cases in this new framework.
1287 - --help, --help=long, -hl
1288 no longer dumps useless items.
1290 lists only specific options.
1291 - --help=recursive, -hr
1292 displays the help of all the embedded packages.
1293 - Remembers environment variables when reconfiguring.
1294 The previous scheme to set envvar before running configure was
1296 what prevented configure from remembering the environment in which
1297 it was run, therefore --recheck was run in an inconsistent
1298 environment. Now, one should run
1300 and then --recheck will work properly. Variables declared with
1301 AC_ARG_VAR are also preserved.
1303 $build defaults to `config.guess`, $host to $build, and then $target
1305 Cross-compilation is a global status of the package, it no longer
1306 depends upon the current language.
1307 Cross compilation is enabled iff the user specified `--host'.
1308 `configure' now fails if it can't run the executables it compiles,
1309 unless cross-compilation is enabled.
1311 The cache file is disabled by default. The new options
1312 `--config-cache', `-C' set the cache to `config.cache'.
1316 Much faster on most architectures.
1317 - concurrent executions
1318 It is safe to use `make -j' with config.status.
1319 - human interface improved
1320 It is possible to invoke
1321 ./config.status foobar
1322 instead of the former form (still valid)
1323 CONFIG_COMMANDS= CONFIG_HEADERS= CONFIG_LINKS= \
1324 CONFIG_FILES=foobar:foo.in:bar.in \
1326 The same holds for configuration headers and links.
1327 You can instantiate unknown files and headers:
1328 ./config.status --header foo.h:foo.h.in --file bar:baz
1329 - has a useful --help
1330 - accepts special file name "-" for stdin/stdout
1335 Specify additional copyright information.
1338 Now expects the identity of the package as argument.
1342 Most macros, if not all, now strictly follow the `one quotation
1343 level' rule. This results in a more predictable expansion.
1346 A sly bug in the AC_REQUIRE machinery, which could produce incorrect
1347 configure scripts, was fixed by Axel Thimm.
1351 Document and ask for the registration of an envvar.
1354 Specifies the file which `configure' should look for when trying to
1355 find the source tree (used to be handled by AC_INIT).
1357 - AC_CONFIG_COMMANDS
1358 To add new actions to config.status. Should be used instead of
1362 Replaces AC_LINK_FILES.
1364 - AC_CONFIG_HEADERS, AC_CONFIG_COMMANDS, AC_CONFIG_SUBDIRS,
1365 AC_CONFIG_LINKS, and AC_CONFIG_FILES
1366 They now obey sh: you should no longer use shell variables as
1367 argument. Instead of
1369 test "$package_foo_enabled" = yes && $my_subdirs="$my_subdirs foo"
1370 AC_CONFIG_SUBDIRS($my_subdirs)
1374 if test "$package_foo_enabled" = yes; then
1375 AC_CONFIG_SUBDIRS(foo)
1379 To format an Autoconf macro's help string so that it looks pretty
1380 when the user executes `configure --help'.
1383 ** Generic Test Macros
1385 The interface of the AC_CHECK families of macros (decl, header,
1386 type, member, func) is now uniform. They support the same set of
1389 - AC_CHECK_DECL, AC_CHECK_DECLS
1390 To check whether a symbol is declared.
1392 - AC_CHECK_SIZEOF, AC_C_CHAR_UNSIGNED.
1393 No longer need a cross-compilation default.
1396 The test it performs is much more robust than previously, and makes
1397 it possible to test builtin types in addition to typedefs.
1398 It is now schizophrenic:
1399 - AC_CHECK_TYPE(TYPE, REPLACEMENT)
1400 remains for backward compatibility, but its use is discouraged.
1401 - AC_CHECK_TYPE(TYPE, IF-FOUND, IF-NOT-FOUND, INCLUDES)
1402 behaves exactly like the other AC_CHECK macros.
1405 Checks whether given types are supported by the system.
1407 - AC_CHECK_MEMBER, AC_CHECK_MEMBERS
1408 Check for given members in aggregates (e.g., pw_gecos in struct
1412 Checks if the compiler supports ISO C, included when needs special
1416 Checking whether the preprocessor indicates missing includes by the
1417 error code. stderr is checked by AC_TRY_CPP only as a fallback.
1420 Takes a language as argument and replaces AC_LANG_C,
1421 AC_LANG_CPLUSPLUS and AC_LANG_FORTRAN77.
1423 - AC_LANG_PUSH, AC_LANG_POP
1424 Are preferred to AC_LANG_SAVE, AC_LANG_RESTORE.
1427 - AC_FUNC_CHOWN, AC_FUNC_MALLOC, AC_FUNC_STRERROR_R,
1428 AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK, AC_FUNC_STAT, AC_FUNC_LSTAT,
1429 AC_FUNC_ERROR_AT_LINE, AC_FUNC_OBSTACK, AC_FUNC_STRTOD, AC_FUNC_FSEEKO.
1433 Sets GETGROUPS_LIBS.
1435 - AC_FUNC_GETLOADAVG
1436 Defines `HAVE_STRUCT_NLIST_N_UN_N_NAME' instead of `NLIST_NAME_UNION'.
1439 Now integrates `AC_DECL_YYTEXT' which is obsoleted.
1442 Arrange for large-file support.
1444 - AC_EXEEXT, AC_OBJEXT
1445 You are no longer expected to use them: their computation is
1446 performed by default.
1448 ** C++ compatibility
1449 Every macro has been revisited in order to support at best CC=c++.
1451 Major changes in Autoconf 2.14:
1452 There was no release of GNU Autoconf 2.14.
1454 Major changes in Autoconf 2.13:
1456 Released 1999-05-01 by Ben Elliston.
1458 * Support for building on Win32 systems where the only available C or
1459 C++ compiler is the Microsoft Visual C++ command line compiler
1460 (`cl'). Additional support for building on Win32 systems which are
1461 using the Cygwin or Mingw32 environments.
1462 * Support for alternative object file and executable file extensions.
1463 On Win32, for example, these are .obj and .exe. These are discovered
1464 using AC_OBJEXT and AC_EXEEXT, which substitute @OBJEXT@ and
1465 @EXEEXT@ in the output, respectively.
1466 * New macros: AC_CACHE_LOAD, AC_CACHE_SAVE, AC_FUNC_SELECT_ARGTYPES,
1467 AC_VALIDATE_CACHED_SYSTEM_TUPLE, AC_SEARCH_LIBS, AC_TRY_LINK_FUNC,
1468 AC_C_STRINGIZE, AC_CHECK_FILE(S), AC_PROG_F77 (and friends).
1469 * AC_DEFINE now has an optional third argument for a description to be
1470 placed in the config header input file (e.g. config.h.in).
1471 * The C++ code fragment compiled for the C++ compiler test had to be
1472 improved to include an explicit return type for main(). This was
1473 causing failures on systems using recent versions of the EGCS C++
1475 * Fixed an important bug in AC_CHECK_TYPE that would cause a configure
1476 script to report that `sometype_t' was present when only `type_t'
1478 * Merge of the FSF version of config.guess and config.sub to modernize
1479 these scripts. Add support for a few new hosts in config.guess.
1480 Incorporate latest versions of install-sh, mkinstalldirs and
1481 texinfo.tex from the FSF.
1482 * autoreconf is capable of running automake if necessary (and
1484 * Support for Fortran 77. See the Texinfo documentation for details.
1485 * Bug fixes and workarounds for quirky bugs in vendor utilities.
1487 Major changes in Autoconf 2.12:
1489 Released 1996-11-26 by David J. MacKenzie
1491 * AC_OUTPUT and AC_CONFIG_HEADER can create output files by
1492 concatenating multiple input files separated by colons, like so:
1493 AC_CONFIG_HEADER(config.h:conf.pre:config.h.in:conf.post)
1494 AC_OUTPUT(Makefile:Makefile.in:Makefile.rules)
1495 The arguments may be shell variables, to compute the lists on the fly.
1496 * AC_LINK_FILES and AC_CONFIG_SUBDIRS may be called multiple times.
1497 * New macro AC_OUTPUT_COMMANDS adds more commands to run in config.status.
1500 Major changes in Autoconf 2.11:
1502 Released November 18th, 1996, by David J. MacKenzie
1504 * AC_PROG_CC and AC_PROG_CXX check whether the compiler works.
1505 They also default CFLAGS/CXXFLAGS to "-g -O2" for gcc, instead of "-g -O".
1506 * AC_REPLACE_FUNCS defines HAVE_foo if the system has the function `foo'.
1507 * AC_CONFIG_HEADER expands shell variables in its argument.
1508 * New macros: AC_FUNC_FNMATCH, AC_FUNC_SETPGRP.
1509 * The "checking..." messages and the source code for test programs that
1510 fail are saved in config.log.
1511 * Another workaround has been added for seds with small command length limits.
1512 * config.sub and config.guess recognize more system types.
1515 Major changes in Autoconf 2.10:
1517 Released May 7th, 1996, by Roland McGrath
1520 * The cache variable names used by `AC_CHECK_LIB(LIB, FUNC, ...)' has
1521 changed: now $ac_cv_lib_LIB_FUNC, previously $ac_cv_lib_LIB.
1523 Major changes in Autoconf 2.9:
1525 Released March 16th, 1996, by Roland McGrath
1529 Major changes in Autoconf 2.8:
1531 Released March 8th, 1996, by Roland McGrath
1535 Major changes in Autoconf 2.7:
1537 Released November 22nd, 1995, by David J. MacKenzie
1541 Major changes in Autoconf 2.6:
1543 Released November 20th, 1995, by David J. MacKenzie
1547 Major changes in Autoconf 2.5:
1549 Released November 17th, 1995, by Roland McGrath
1551 * New configure options --bindir, --libdir, --datadir, etc., with
1552 corresponding output variables.
1553 * New macro: AC_CACHE_CHECK, to make using the cache easier.
1554 * config.log contains the command being run as well as any output from it.
1555 * AC_CHECK_LIB can check for libraries with "." or "/" or "+" in their name.
1556 * AC_PROG_INSTALL doesn't cache a name for install-sh, for sharing caches.
1557 * AC_CHECK_PROG, AC_PATH_PROG, AC_CHECK_PROGS, AC_PATH_PROGS, and
1558 AC_CHECK_TOOL can search a path other than $PATH.
1559 * AC_CHECK_SIZEOF takes an optional size to use when cross-compiling.
1561 Major changes in Autoconf 2.4:
1563 Released June 14th, 1995, by David J. MacKenzie
1565 * Fix a few bugs found by Emacs testers.
1567 Major changes in Autoconf 2.3:
1569 Released March 27th, 1995, by David J. MacKenzie
1571 * Fix the cleanup trap in several ways.
1572 * Handle C compilers that are picky about option placement.
1573 * ifnames gets the version number from the right directory.
1575 Major changes in Autoconf 2.2:
1577 Released March 8th, 1995, by David J. MacKenzie
1579 * The ifnames utility is much faster but requires a "new awk" interpreter.
1580 * AC_CHECK_LIB and AC_HAVE_LIBRARY check and add the new
1581 library before existing libs, not after, in case it uses them.
1582 * New macros: AC_FUNC_GETPGRP, AC_CHECK_TOOL.
1583 * Lots of bug fixes.
1584 * Many additions to the TODO file :-)
1586 Major changes in Autoconf 2.1:
1588 Released November 4th, 1994, by David J. MacKenzie
1591 * More explanations in the manual.
1592 * Fix a spurious failure in the testsuite.
1593 * Clarify some warning messages.
1594 * autoreconf by default only rebuilds configure and config.h.in files
1595 that are older than any of their particular input files; there is a
1596 --force option to use after installing a new version of Autoconf.
1598 Thanks to everybody who's submitted changes and additions to Autoconf!
1599 I've incorporated many of them, and am still considering others for
1600 future releases -- but I didn't want to postpone this release indefinitely.
1602 Caution: don't indiscriminately rebuild configure scripts with
1603 Autoconf version 2. Some configure.in files need minor adjustments to
1604 work with it; the documentation has a chapter on upgrading. A few
1605 configure.in files, including those for GNU Emacs and the GNU C
1606 Library, need major changes because they relied on undocumented
1607 internals of version 1. Future releases of those packages will have
1608 updated configure.in files.
1610 It's best to use GNU M4 1.3 (or later) with Autoconf version 2.
1611 Autoconf now makes heavy use of M4 diversions, which were implemented
1612 inefficiently in GNU M4 releases before 1.3.
1614 Major changes in Autoconf 2.0:
1616 Released October 26th, 1994, by David J. MacKenzie
1618 ** New copyright terms:
1619 * There are no restrictions on distribution or use of configure scripts.
1622 * Autoconf manual is reorganized to make information easier to find
1623 and has several new indexes.
1624 * INSTALL is reorganized and clearer and is now made from Texinfo source.
1627 * autoscan to generate a preliminary configure.in for a package by
1628 scanning its source code for commonly used nonportable functions,
1629 programs, and header files.
1630 * ifnames to list the symbols used in #if and #ifdef directives in a
1632 * autoupdate to update a configure.in to use the version 2 macro names.
1633 * autoreconf to recursively remake configure and configuration header
1634 files in a source tree.
1636 ** Changed utilities:
1637 * autoheader can take pieces of acconfig.h to replace config.h.{top,bot}.
1638 * autoconf and autoheader can look for package-local definition files
1639 in an alternate directory.
1642 * AC_CACHE_VAL to share results of tests between configure runs.
1643 * AC_DEFUN to define macros, automatically AC_PROVIDE them, and ensure
1644 that macros invoked with AC_REQUIRE don't interrupt other macros.
1645 * AC_CONFIG_AUX_DIR, AC_CANONICAL_SYSTEM, AC_CANONICAL_HOST, AC_LINK_FILES to
1646 support deciding unguessable features based on the host and target types.
1647 * AC_CONFIG_SUBDIRS to recursively configure a source tree.
1648 * AC_ARG_PROGRAM to use the options --program-prefix,
1649 --program-suffix, and --program-transform-name to change the names
1650 of programs being installed.
1651 * AC_PREFIX_DEFAULT to change the default installation prefix.
1652 * AC_TRY_COMPILE to compile a test program without linking it.
1653 * AC_CHECK_TYPE to check whether sys/types.h or stdlib.h defines a given type.
1654 * AC_CHECK_LIB to check for a particular function and library.
1655 * AC_MSG_CHECKING and AC_MSG_RESULT to print test results, on a single line,
1656 whether or not the test succeeds. They obsolete AC_CHECKING and AC_VERBOSE.
1657 * AC_SUBST_FILE to insert one file into another.
1658 * AC_FUNC_MEMCMP to check whether memcmp is 8-bit clean.
1659 * AC_FUNC_STRFTIME to find strftime even if it's in -lintl.
1660 * AC_FUNC_GETMNTENT to find getmntent even if it's in -lsun or -lseq.
1661 * AC_HEADER_SYS_WAIT to check whether sys/wait.h is POSIX.1 compatible.
1664 * Many macros renamed systematically, but old names are accepted for
1665 backward compatibility.
1666 * AC_OUTPUT adds the "automatically generated" comment to
1667 non-Makefiles where it finds @configure_input@ in an input file, to
1668 support files with various comment syntaxes.
1669 * AC_OUTPUT does not replace "prefix" and "exec_prefix" in generated
1670 files when they are not enclosed in @ signs.
1671 * AC_OUTPUT allows the optional environment variable CONFIG_STATUS to
1672 override the file name "config.status".
1673 * AC_OUTPUT takes an optional argument for passing variables from
1674 configure to config.status.
1675 * AC_OUTPUT and AC_CONFIG_HEADER allow you to override the input-file names.
1676 * AC_OUTPUT automatically substitutes the values of CFLAGS, CXXFLAGS,
1677 CPPFLAGS, and LDFLAGS from the environment.
1678 * AC_PROG_CC and AC_PROG_CXX now set CFLAGS and CXXFLAGS, respectively.
1679 * AC_PROG_INSTALL looks for install-sh or install.sh in the directory
1680 specified by AC_CONFIG_AUXDIR, or srcdir or srcdir/.. or
1681 srcdir/../.. by default.
1682 * AC_DEFINE, AC_DEFINE_UNQUOTED, and AC_SUBST are more robust and smaller.
1683 * AC_DEFINE no longer prints anything, because of the new result reporting
1684 mechanism (AC_MSG_CHECKING and AC_MSG_RESULT).
1685 * AC_VERBOSE pays attention to --quiet/--silent, not --verbose.
1686 * AC_ARG_ENABLE and AC_ARG_WITH support whitespace in the arguments to
1687 --enable- and --with- options.
1688 * AC_CHECK_FUNCS and AC_CHECK_HEADERS take optional shell commands to
1689 execute on success or failure.
1690 * Checking for C functions in C++ works.
1693 * AC_REMOTE_TAPE and AC_RSH removed; too specific to tar and cpio, and
1694 better maintained with them.
1695 * AC_ARG_ARRAY removed because no one was likely using it.
1696 * AC_HAVE_POUNDBANG replaced with AC_SYS_INTERPRETER, which doesn't
1697 take arguments, for consistency with all of the other specific checks.
1700 * Comes with config.sub and config.guess, and uses them optionally.
1701 * Uses config.cache to cache test results. An alternate cache file
1702 can be selected with the --cache-file=FILE option.
1703 * Uses optional shell scripts $prefix/share/config.site and
1704 $prefix/etc/config.site to perform site or system specific initializations.
1705 * configure saves compiler output to ./config.log for debugging.
1706 * New files autoconf.m4 and autoheader.m4 load the other Autoconf macros.
1707 * acsite.m4 is the new name for the system-wide aclocal.m4.
1708 * Has a DejaGnu test suite.
1710 Major changes in Autoconf 1.11:
1712 * AC_PROG_INSTALL calls install.sh with the -c option.
1713 * AC_SET_MAKE cleans up after itself.
1714 * AC_OUTPUT sets prefix and exec_prefix if they weren't set already.
1715 * AC_OUTPUT prevents shells from looking in PATH for config.status.
1717 Plus a few other bug fixes.
1719 Major changes in Autoconf 1.10:
1721 * autoheader uses config.h.bot if present, analogous to config.h.top.
1722 * AC_PROG_INSTALL looks for install.sh in srcdir or srcdir/.. and
1724 * AC_PROG_CXX looks for cxx as a C++ compiler.
1726 Plus several bugs fixed.
1728 Major changes in Autoconf 1.9:
1730 * AC_YYTEXT_POINTER replaces AC_DECLARE_YYTEXT.
1731 * AC_SIZEOF_TYPE generates the cpp symbol name automatically,
1732 and autoheader generates entries for those names automatically.
1733 * AC_FIND_X gets the result from xmkmf correctly.
1734 * AC_FIND_X assumes no X if --without-x was given.
1735 * AC_FIND_XTRA adds libraries to the variable X_EXTRA_LIBS.
1736 * AC_PROG_INSTALL finds OSF/1 installbsd.
1738 Major changes in Autoconf 1.8:
1741 * New macros AC_LANG_C, AC_LANG_CPLUSPLUS, AC_LANG_SAVE, AC_LANG_RESTORE,
1742 AC_PROG_CXX, AC_PROG_CXXCPP, AC_REQUIRE_CPP
1743 for checking both C++ and C features in one configure script.
1744 * New macros AC_CHECKING, AC_VERBOSE, AC_WARN, AC_ERROR for printing messages.
1745 * New macros AC_FIND_XTRA, AC_MMAP, AC_SIZEOF_TYPE, AC_PREREQ,
1746 AC_SET_MAKE, AC_ENABLE.
1749 * AC_FIND_X looks for X in more places.
1750 * AC_PROG_INSTALL defaults to install.sh instead of cp, if it's in srcdir.
1751 install.sh is distributed with Autoconf.
1752 * AC_DECLARE_YYTEXT has been removed because it can't work, pending
1753 a rewrite of quoting in AC_DEFINE.
1754 * AC_OUTPUT adds its comments in C format when substituting in C files.
1755 * AC_COMPILE_CHECK protects its ECHO-TEXT argument with double quotes.
1757 ** New or changed command line options:
1758 * configure accepts --enable-FEATURE[=ARG] and --disable-FEATURE options.
1759 * configure accepts --without-PACKAGE, which sets withval=no.
1760 * configure accepts --x-includes=DIR and --x-libraries=DIR.
1761 * Giving --with-PACKAGE no argument sets withval=yes instead of withval=1.
1762 * configure accepts --help, --version, --silent/--quiet, --no-create options.
1763 * configure accepts and ignores most other Cygnus configure options, and
1764 warns about unknown options.
1765 * config.status accepts --help, --version options.
1767 ** File names and other changes:
1768 * Relative srcdir values are not made absolute.
1769 * The values of @prefix@ and @exec_prefix@ and @top_srcdir@ get substituted.
1770 * Autoconf library files are installed in ${datadir}/autoconf, not ${datadir}.
1771 * autoheader optionally copies config.h.top to the beginning of config.h.in.
1772 * The example Makefile dependencies for configure et al. work better.
1773 * Namespace cleanup: all shell variables used internally by Autoconf
1774 have names beginning with `ac_'.
1776 More big improvements are in process for future releases, but have not
1777 yet been (variously) finished, integrated, tested, or documented enough
1780 Major changes in Autoconf 1.7:
1782 * New macro AC_OBSOLETE.
1783 * Bugs in Makefile.in fixed.
1784 * AC_LONG_FILE_NAMES improved.
1786 Major changes in Autoconf 1.6:
1788 * New macro AC_LONG_64_BITS.
1789 * Multiple .h files can be created.
1790 * AC_FIND_X looks for X files directly if it doesn't find xmkmf.
1791 * AC_ALLOCA defines C_ALLOCA if using alloca.c.
1792 * --with-NAME can take a value, e.g., --with-targets=sun4,hp300bsd.
1793 * Unused --no-create option to configure removed.
1794 * autoheader doesn't change the timestamp of its output file if
1795 the file didn't change.
1796 * All macros that look for libraries now use AC_HAVE_LIBRARY.
1797 * config.status checks three optional environment variables to
1798 modify its behavior.
1799 * The usual bug fixes.
1801 Major changes in Autoconf 1.5:
1803 * New macros AC_FIND_X, AC_OFF_T, AC_STAT_MACROS_BROKEN, AC_REVISION.
1804 * autoconf and autoheader scripts have GNU standards conforming
1805 --version and --help options (they print their message and exit).
1808 Major changes in Autoconf 1.4:
1810 * New macros AC_HAVE_POUNDBANG, AC_TIME_WITH_SYS_TIME, AC_LONG_DOUBLE,
1811 AC_GETGROUPS_T, AC_DEFINE_UNQUOTED.
1812 * autoconf and autoheader use the M4 environment variable to determine the
1813 name of the M4 program to use.
1814 * The --macrodir option to autoconf and autoheader specifies the directory
1815 in which acspecific.m4, acgeneral.m4, etc. reside if not the default.
1816 * autoconf and autoheader can take `-' as their file names, which means to
1817 read stdin as input.
1818 * Resulting configure scripts can take a --verbose option which causes them
1819 to print the results of their tests.
1820 * AC_DEFINE quotes its second argument in such a way that spaces, magic
1821 shell characters, etc. will be preserved during various stages of
1822 expansion done by the shell. If you don't want this, use
1823 AC_DEFINE_UNQUOTED instead.
1824 * Much textual processing done with external calls to tr and sed have been
1825 internalized with builtin M4 `patsubst' and `translit' calls.
1826 * AC_OUTPUT doesn't hardwire the file names it outputs. Instead, you can
1827 set the shell variables `gen_files' and `gen_config' to the list of
1828 file names to output.
1829 * AC_DECLARE_YYTEXT does an AC_SUBST of `LEX_OUTPUT_ROOT', which may be
1830 "lex.yy" or "lexyy", depending on the system.
1831 * AC_PROGRAMS_CHECK takes an optional third arg. If given, it is used as
1833 * If AC_ALLOCA chooses alloca.c, it also defines STACK_DIRECTION.
1834 * AC_CONST works much more reliably on more systems.
1837 Major changes in Autoconf 1.3:
1839 configure no longer requires awk for packages that use a config.h.
1840 Support handling --with-PACKAGE options.
1841 New `autoheader' script to create `config.h.in' from `configure.in'.
1842 Ignore troublesome -lucb and -lPW when searching for alloca.
1843 Rename --exec_prefix to --exec-prefix for GNU standards conformance.
1844 Improve detection of STDC library.
1845 Add AC_HAVE_LIBRARY to check for non-default libraries.
1846 Function checking should work with future GNU libc releases.
1848 Major changes in Autoconf 1.2:
1850 The --srcdir option is now usually unnecessary.
1851 Add a file containing sample comments describing CPP macros.
1852 A comment in config.status tells which host it was configured on.
1853 Substituted variable values can now contain commas.
1854 Fix bugs in various feature checks.
1856 Major changes in Autoconf 1.1:
1858 Added AC_STRCOLL macro.
1859 Made AC_GETLOADAVG check for more things.
1860 AC_OUTPUT argument is now optional.
1865 Copyright (C) 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002,
1866 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
1868 This program is free software: you can redistribute it and/or modify
1869 it under the terms of the GNU General Public License as published by
1870 the Free Software Foundation, either version 3 of the License, or
1871 (at your option) any later version.
1873 This program is distributed in the hope that it will be useful,
1874 but WITHOUT ANY WARRANTY; without even the implied warranty of
1875 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1876 GNU General Public License for more details.
1878 You should have received a copy of the GNU General Public License
1879 along with this program. If not, see <http://www.gnu.org/licenses/>.