1 GNU Autoconf NEWS - User visible changes.
3 * Major changes in Autoconf 2.61b (????-??-??)
5 ** Many optimizations have been applied to make overall execution faster.
7 ** Autotest now makes use of shell functions.
9 ** config.status now uses awk instead of sed also for config headers.
11 - As a side effect, AC_DEFINE and AC_DEFINE_UNQUOTED now handle multi-line
12 values, i.e., backslash-newline combinations are handled correctly.
13 Further, for config headers, the total size of values is not limited by
14 the POSIX length limit of text lines any more, only each single line.
16 ** New config variable `top_build_prefix'.
18 ** Autoconf is now licensed under the General Public License version 3
19 or later (GPLv3+). As with earlier versions, the license includes
20 an exception clause so that you may release a configure script
21 generated by autoconf under the license of your own program.
22 FIXME - revisit this line once exception clause is finalized.
24 ** New Autoconf macros:
25 AC_AUTOCONF_VERSION AC_OPENMP AC_PATH_PROGS_FEATURE_CHECK
27 ** It is now possible to undo the work of autoconf, autoheader and
28 autoreconf with the --clean option.
30 ** AC_C_BIGENDIAN now supports universal binaries a la Mac OS X.
32 ** AC_C_RESTRICT now prefers to #define 'restrict' to a variant spelling
33 like '__restrict' if the variant spelling is available, as this is
34 more likely to work when mixing C and C++ code.
36 ** AC_CHECK_ALIGNOF's type argument T is now documented better: it must
37 be a string of tokens such that "T y;" is a valid member declaration
40 ** AC_CHECK_SIZEOF now accepts objects as well as types: the general rule
41 is that sizeof (X) works, then AC_CHECK_SIZEOF (X) should work.
43 ** AC_CHECK_TYPE and AC_CHECK_TYPES now work on any C type-name; formerly,
44 they did not work for function types. In C++, they now work on any
45 type-id that can be the operand of sizeof; this is similar to C,
46 except it excludes anonymous struct and union types. Formerly,
47 some (but not all) C++ types involving anonymous struct and union
48 were accepted, though this was not documented.
50 ** AC_CONFIG_LINKS now prefers to link against files in the build tree
51 if found, and it works to link against a file of the same name in
52 the source tree, even if both trees coincide.
54 ** AC_INIT no longer alters $@; regression introduced in 2.60.
56 ** AC_USE_SYSTEM_EXTENSIONS now defines _ALL_SOURCE for Interix platforms.
58 ** AS_HELP_STRING no longer underquotes its first argument; it also handles
59 the case where the first argument contains single-quoted commas.
60 For example, "AS_HELP_STRING([-a, [--arg[=foo]]], [bar])" produces:
61 " -a, --arg=[foo] bar"
62 Additionally, the macro now takes two additional arguments,
63 indent-column and wrap-column; these should not normally be needed,
64 but can be used to fine-tune how the output text is wrapped.
66 ** The command 'autoconf -' now correctly processes a file from stdin.
68 ** For all of the directory arguments for 'configure', such as '--prefix'
69 or '--bindir', trailing slashes are stripped. As an example, if
70 tab completion in the user's shell appends trailing slashes, the
71 command './configure --prefix=/usr/' will still result in an
72 expanded libdir value of /usr/lib, not /usr//lib.
74 ** `configure --help=recursive' now works in read-only trees and from
75 unconfigured build trees.
77 ** AT_BANNER is now documented.
79 ** AT_SETUP now handles macro expansions properly when calculating line
82 ** Autotest now determines $srcdir correctly.
84 ** Autoconf now requires GNU M4 1.4.5 or later. Earlier versions of M4 have
85 a bug in macro tracing that interferes with the interaction between
86 Autoconf and Automake. GNU M4 1.4.8 or later is recommended. The
87 configure search for a working M4 is improved.
89 ** Documentation for m4sugar is improved.
91 - The following macros were previously available as undocumented
92 interfaces; the macros are now documented as stable interfaces.
94 __oline__ m4_assert m4_bmatch m4_bpatsubsts m4_car m4_case
95 m4_cdr m4_default m4_divert_once m4_divert_pop m4_divert_push
96 m4_divert_text m4_do m4_errprintn m4_fatal m4_flatten
97 m4_ifndef m4_ifset m4_ifval m4_ifvaln m4_location
98 m4_n m4_shiftn m4_strip m4_warn
100 - The following macros were previously available as undocumented
101 interfaces, but had bug fixes or semantic changes as part of this
102 release. Packages that relied on the undocumented behavior
103 should be analyzed to make sure they will still work with the
104 new documented behavior.
106 m4_cmp m4_list_cmp m4_join m4_map m4_map_sep m4_sign
107 m4_text_box m4_text_wrap m4_version_compare
109 - Packages using the undocumented m4sugar macro m4_PACKAGE_VERSION
110 should consider using the new AC_AUTOCONF_VERSION instead.
112 - m4sugar macros that are not documented in the manual are still
113 deemed experimental, and should not be used outside of Autoconf.
115 ** The m4sugar macros m4_append and m4_append_uniq, first documented in
116 2.60, have been fixed to treat both the string and the separator
117 arguments consistently with regards to quoting. Prior to this fix,
118 m4_append_uniq could mistakenly duplicate entries if the expansion
119 of the separator resulted in a different string (for example, if it
120 contained quotes, a comma, or a macro name). However, it means
121 that programs previously using
122 m4_append([name], [string], [[, ]])
123 are now using a four-character separator instead of the intended
124 comma and space. If you need portability to earlier versions of
125 Autoconf, you can insert the following snippet after AC_INIT but
126 before any other macro expansions, to enforce the new semantics:
127 m4_pushdef([m4_append], [m4_define([$1],
128 m4_ifdef([$1], [m4_defn([$1])[$3]])[$2])])
129 Additionally, m4_append_uniq now takes optional parameters that can
130 be used to take action depending on whether anything was appended,
131 and warns if a non-empty separator occurs within the string being
132 appended, since that can lead to duplicates.
134 ** The following m4sugar macros are new:
135 m4_append_uniq_w m4_apply m4_combine m4_cond m4_count
136 m4_dquote_elt m4_echo m4_expand m4_ignore m4_make_list m4_max
137 m4_min m4_newline m4_shift2 m4_shift3 m4_unquote
139 ** Warnings are now generated by default when an installer invokes
140 'configure' with an unknown --enable-* or --with-* option.
141 These warnings can be disabled with the new AC_DISABLE_OPTION_CHECKING
142 macro, or by invoking 'configure' with --disable-option-checking.
144 ** For portability with the eventual M4 2.0, macros should no longer use
145 anything larger than $9 to refer to arguments.
147 ** Existing obsolete macros
148 The documentation for the following macros is adjusted to make it
149 more clear that they have previously been marked obsolete, as their
150 functionality can be accomplished by other macros. We have no
151 current plans to remove them from Autoconf.
153 AC_ENABLE AC_STRUCT_ST_BLKSIZE AC_STRUCT_ST_RDEV AC_WITH
155 ** Newly obsolete macros
156 The following macros have been marked obsolete, as they only
157 perform a subset of AC_USE_SYSTEM_EXTENSIONS. We have no current
158 plans to remove them.
160 AC_AIX AC_GNU_SOURCE AC_ISC_POSIX AC_MINIX
162 ** AC_C_LONG_DOUBLE is obsolescent.
163 The documentation now says that AC_C_LONG_DOUBLE is obsolescent: it
164 tests for problems that are so old that it is no longer of
165 practical importance on current systems. New programs need not use
166 AC_C_LONG_DOUBLE. We have no current plans to remove it.
168 ** AC_DIAGNOSE, AC_WARNING, and AC_FATAL are obsolescent.
169 The documentation now favors the use of M4sugar macros m4_warn and
170 m4_fatal, since the naming makes it more obvious that the
171 diagnostics are associated with M4 expansion (ie. when running
172 `autoconf'), and offers less confusion with the AC_MSG_ERROR,
173 AC_MSG_FAILURE, and AC_MSG_WARN macros which manage diagnostics
174 when running `configure'. We have no current plans to remove these
177 * Major changes in Autoconf 2.61a (2006-12-11)
179 ** AC_FUNC_FSEEKO was broken in 2.61; it didn't make fseeko and ftello visible
180 on many platforms. This has been fixed.
182 ** AC_FUNC_SETVBUF_REVERSED is now obsolete. It is still defined for backward
183 compatibility but it does nothing. The macro was already
184 obsolescent, as the last systems to have the problem were those
185 based on SVR2, which became obsolete in 1987. The macro had bugs
186 on some modern systems and could no longer be maintained reliably
187 due to lack of ancient systems to test it on.
189 ** config.status now uses awk instead of sed for most substitutions, for speed.
191 - As a side effect multi-line values of substituted variables no
192 longer have a small limit in total size, though for portability
193 each line should not exceed the POSIX length limit for text lines.
195 - It is now documented that Makefile.in should not contain
196 overlapping variable occurrences, e.g., @VAR1@VAR2@.
197 Autoconf's behavior was always iffy in such cases, and the
198 awk implementation has changed the behavior.
200 ** Many uses of 'echo' have been rewritten so that Autoconf-generated
201 scripts have fewer problems with strings or file names containing
202 embedded special characters such as backslash or leading "-". This
203 was implemented by using `printf '%s\n' "$foo"' instead of `echo
204 "$foo"' when printf works. Due to the implementation technique
205 used, Autoconf-generated scripts now run considerably more slowly
206 on ancient implementations lacking printf. However, this should
207 not be a problem, since Autoconf-generated scripts in practice
208 invariably find a more-modern shell these days.
210 * Major changes in Autoconf 2.61 (2006-11-17)
212 ** New macros AC_C_FLEXIBLE_ARRAY_MEMBER, AC_C_VARARRAYS.
214 ** AC_ARG_ENABLE and AC_ARG_WITH now allow '.' in feature and package names.
216 * Major changes in Autoconf 2.60b (2006-10-22)
219 Autoconf-generated shell scripts no longer export BIN_SH, due to
220 configuration hassles with this. Installers who need BIN_SH in
221 their environment should set it before invoking 'configure' and
222 'make'. As far as we know, this affects only Unixware installations.
224 ** Obsolescent macros
225 The documentation now says that the following macros are obsolescent,
226 as they are superseded by Gnulib:
228 AC_FUNC_FNMATCH AC_FUNC_FNMATCH_GNU AC_FUNC_GETLOADVG AC_REPLACE_FNMATCH
230 New programs should use the Gnulib counterparts of these macros.
231 We have no current plans to remove them from Autoconf.
233 ** AC_COMPUTE_INT no longer caches or reports results.
235 ** AC_CHECK_DECL now also works with aggregate objects.
237 ** AC_USE_SYSTEM_EXTENSIONS now defines _TANDEM_SOURCE for NonStop platforms.
239 ** GNU M4 1.4.7 or later is now recommended.
242 New M4sugar macro, which is more secure than the POSIX M4 maketemp.
245 Now an alias for m4_mkstemp.
247 * Major changes in Autoconf 2.60a (2006-08-25)
249 ** GNU M4 1.4.6 or later is now recommended.
251 ** The check for C99 now tests for varargs macros, as documented.
252 It also tests that the preprocessor supports 64-bit integers.
254 ** Autoconf now uses constructs like "#ifdef HAVE_STDLIB_H" rather than
255 "#if HAVE_STDLIB_H", so that it now works with "gcc -Wundef -Werror".
257 ** The functionality of the undocumented _AC_COMPUTE_INT is now provided
258 by a public and documented macro, AC_COMPUTE_INT. The parameters to the
259 two macros are different, so autoupdate will not change the old private name
260 to the new one. _AC_COMPUTE_INT may be removed in a future release.
262 ** AC_TYPE_LONG_LONG_INT and AC_TYPE_UNSIGNED_LONG_LONG_INT now require
263 that long long types be at least 64 bits wide, as C99 and tradition
264 requires. Formerly, they accepted implementations of any width.
267 * Major changes in Autoconf 2.60
269 Released 2006-06-23, by Ralf Wildenhues.
271 ** Autoconf no longer depends on whether m4wrap is FIFO (as Posix requires)
272 or LIFO (as in GNU M4 1.4.x). GNU M4 2.0 is expected to conform to Posix
273 here, so m4wrap/m4_wrap users should no longer depend on LIFO behavior.
275 ** Provide a way to turn off warnings about the changed directory variables.
277 * Major changes in Autoconf 2.59d
279 Released 2006-06-05, by Ralf Wildenhues.
281 ** GNU make now recommended for VPATH builds
282 INSTALL now suggests VPATH builds (e.g., "sh ../srcdir/configure")
283 only if you use GNU make. In practice, other 'make' implementations
284 have too many subtle incompatibilities in their support for VPATH.
285 Many packages (including Autoconf itself) are portable to other
286 'make' implementations, but some packages are not, and recommending
287 GNU make keeps the installation instructions simpler.
289 ** Even more safety checks for the new Directory variables:
290 Warn about suspicious `${datarootdir}' found in config files output.
292 ** AC_TRY_COMMAND, AC_TRY_EVAL, ac_config_guess, ac_config_sub, ac_configure
293 These never-documented macros and variables have been marked with
294 comments saying that they may be removed in a future release,
295 because their use can lead to unintended code being executed.
296 If you need functionality that only these macros or variables
297 currently supply, please write bug-autoconf@gnu.org.
299 ** AC_SUBST, AC_DEFINE
300 Literal arguments to these are passed to m4_pattern_allow now.
303 Passing 'ac_cv_prog_cc_stdc=no' to 'configure' now sets ac_cv_prog_cc_c99
304 and ac_cv_prog_cc_c89 to 'no' as well, for backward compatibility with
305 obsolete K&R tests in the Automake test suite.
314 Now more robust with special characters in file names, or when
315 multiple processes create the same directory at the same time.
317 ** Obsolescent macros
318 The documentation now says that the following macros are obsolescent:
319 they test for problems that are so old that they are no longer of
320 practical importance on current systems.
322 AC_C_BACKSLASH_A AC_FUNC_MEMCMP AC_HEADER_DIRENT
323 AC_C_CONST AC_FUNC_SELECT_ARGTYPES AC_HEADER_STAT
324 AC_C_PROTOTYPES AC_FUNC_SETPGRP AC_HEADER_STDC
325 AC_C_STRINGIZE AC_FUNC_SETVBUF_REVERSED AC_HEADER_SYS_WAIT
326 AC_C_VOLATILE AC_FUNC_STAT AC_HEADER_TIME
327 AC_FUNC_CLOSEDIR_VOID AC_FUNC_STRFTIME AC_ISC_POSIX
328 AC_FUNC_GETPGRP AC_FUNC_UTIME_NULL AC_PROG_GCC_TRADITIONAL
329 AC_FUNC_LSTAT AC_FUNC_VPRINTF AC_STRUCT_TM
331 New programs need not use these macros. We have no current plans to
335 For compatibility with future Libtool 2.0, autoreconf will invoke
336 libtoolize with the option `--ltdl' now, if LT_CONFIG_LTDL_DIR is
339 * Major changes in Autoconf 2.59c
341 Released 2006-04-12, by Ralf Wildenhues.
343 ** The configure command now redirects standard input from /dev/null,
344 to help avoid problems with subsidiary commands that might mistakenly
345 read standard input. AS_ORIGINAL_STDIN_FD points to the original
346 standard input before this redirection, if you really want configure to
347 read from standard input.
349 ** Directory variables adjusted to recent changes in the GNU Coding Standards.
350 The following directory variables are new:
352 datarootdir read-only architecture-independent data root [PREFIX/share]
353 localedir locale-specific message catalogs [DATAROOTDIR/locale]
354 docdir documentation root [DATAROOTDIR/doc/PACKAGE]
355 htmldir html documentation [DOCDIR]
356 dvidir dvi documentation [DOCDIR]
357 pdfdir pdf documentation [DOCDIR]
358 psdir ps documentation [DOCDIR]
360 The following variables have new default values:
362 datadir read-only architecture-independent data [DATAROOTDIR]
363 infodir info documentation [DATAROOTDIR/info]
364 mandir man documentation [DATAROOTDIR/man]
366 This means that if you use any of `@datadir@', `@infodir@', or
367 `@mandir@' in a file, you will have to ensure `${datarootdir}' is
368 defined in this file. As a temporary measure, if any of those are
369 found but no mention of `datarootdir', the substitutions will be
370 replaced with values that do not contain `${datarootdir}', and a
371 warning will be issued.
373 ** @top_builddir@ is now a dir name: it is always nonempty and doesn't have
374 a trailing slash. Similar change will be made to ac_top_builddir in a
375 future release; the old style value, which matches (../)*, is (and will
376 continue to be) available as ac_top_build_prefix.
379 New macro to check for support of 'typeof' syntax a la GNU C.
381 ** AC_CHECK_DECLS_ONCE, AC_CHECK_FUNCS_ONCE, AC_CHECK_HEADERS_ONCE
382 New "once-only" variants of commonly-used macros, to make 'configure'
383 smaller and faster in common cases.
386 New macro to check for strtold with C99 semantics.
389 New macro that lets builder disable assertions at 'configure'-time.
392 Now checks for X11/Xlib.h and XrmInitialize (X proper) rather than
393 X11/Intrinsic.h and XtMalloc (Xt).
395 ** AC_PRESERVE_HELP_ORDER
396 New macro that causes `configure' to display help strings for AC_ARG_ENABLE
397 and AC_ARG_WITH arguments in one region, in the order defined. The default
398 behavior is to group options of each classes separately.
400 ** AC_PROG_CC, AC_PROG_CXX
401 No longer automatically arrange to declare the 'exit' function of C,
402 when a C++ compiler is used. Standard Autoconf macros no longer use
403 'exit', so this is no longer an issue for them. If you use C++, and
404 want to call 'exit', you'll have to arrange for its declaration
405 yourself. But we now suggest you return from 'main' instead.
407 ** AC_PROG_CC_C89, AC_PROG_CC_C99
408 New macros for ISO C99 support. AC_PROG_CC_C89 and AC_PROG_CC_C99
409 check for ANSI C89 and ISO C99 support respectively.
412 Has been unobsoleted, and will check if the compiler supports ISO
413 C99, falling back to ANSI C89 if not. ac_cv_prog_cc_stdc is
414 retained for backwards compatibility, assuming the value of
415 ac_cv_prog_cc_c99 or ac_cv_prog_cc_c89 (whichever is valid, in
418 ** AC_STRUCT_DIRENT_D_INO, AC_STRUCT_DIRENT_D_TYPE
419 New macros for checking commonly-used members of struct dirent.
422 The substituted value can now contain newlines.
425 The substitution now occurs only when @variable@ is on a line by itself,
426 optionally surrounded by spaces and tabs. The whole line is replaced.
428 ** AC_TYPE_LONG_DOUBLE, AC_TYPE_LONG_DOUBLE_WIDER
429 New macros to check for long double, and whether it is wider than double.
430 The old macro AC_C_TYPE_LONG_DOUBLE has been marked as obsolete;
431 applications should switch to the new macro.
433 ** AC_TYPE_INT8_T, AC_TYPE_INT16_T, AC_TYPE_INT32_T, AC_TYPE_INT64_T,
434 AC_TYPE_INTMAX_T, AC_TYPE_INTPTR_T, AC_TYPE_LONG_LONG_INT, AC_TYPE_SSIZE_T,
435 AC_TYPE_UINT8_T, AC_TYPE_UINT16_T, AC_TYPE_UINT32_T, AC_TYPE_UINT64_T,
436 AC_TYPE_UINTMAX_T, AC_TYPE_UINTPTR_T, AC_TYPE_UNSIGNED_LONG_LONG_INT
437 New macros to check for C99 and POSIX types.
439 ** AC_USE_SYSTEM_EXTENSIONS
440 New macro to enable extensions to Posix.
443 New macro which is defined to the name of the first declared config header
444 or undefined if no config headers have been declared yet.
447 The macro correctly handles quadrigraphs now.
449 ** AS_BOURNE_COMPATIBLE, AS_SHELL_SANITIZE, AS_CASE
450 These macros are new or published now.
453 New macro for copyright notices in testsuite files.
455 ** ALLOCA, LIBOBJS, LTLIBOBJS
456 Object names added to these variables are now prefixed with `${LIBOBJDIR}',
457 as in `${LIBOBJDIR}alloca.o'. LIBOBJDIR is meant to be defined from
458 `Makefile.in' in case the object files lie in a different directory.
459 The LIBOBJDIR feature is experimental.
462 Supports --no-recursive now.
464 ** New macros to support Erlang/OTP.
465 New macros for configuring paths to Erlang tools and libraries:
466 AC_ERLANG_PATH_ERLC, AC_ERLANG_NEED_ERLC, AC_ERLANG_PATH_ERL,
467 AC_ERLANG_NEED_ERL, AC_ERLANG_CHECK_LIB, AC_ERLANG_SUBST_ROOT_DIR,
468 AC_ERLANG_SUBST_LIB_DIR.
470 New macros for configuring installation of Erlang libraries:
471 AC_ERLANG_SUBST_INSTALL_LIB_DIR, AC_ERLANG_SUBST_INSTALL_LIB_SUBDIR.
473 ** The manual now mentions Gnulib more prominently.
475 ** New macros to support Objective C.
476 AC_PROG_OBJC, AC_PROG_OBJCPP.
478 * Major changes in Autoconf 2.59b
480 Released 2004-08-20, by Paul Eggert.
483 New macro that computes the default alignment of a type.
485 ** AC_CHECK_TOOL, AC_PATH_TOOL, AC_CHECK_TOOLS
486 When cross-compiling, these macros will give a warning if the tool
487 is not prefixed. In the future, unprefixed cross tools will not
488 be detected; please consult the info documentation for information
489 about the reason of this change.
491 ** AC_CHECK_TARGET_TOOL, AC_PATH_TARGET_TOOL, AC_CHECK_TARGET_TOOLS
492 New macros that detect programs whose name is prefixed with the
493 target type, if the build type and target type are different.
495 ** AC_REQUIRE_AUX_FILE
496 New trace macro that declares expected auxiliary files.
499 New macro that tests for a grep program that accepts as a long a line
502 ** AC_PROG_EGREP, AC_PROG_FGREP
503 These macros now require AC_PROG_GREP, and try EGREP="$GREP -E" and
504 FGREP="$GREP -F" respectively if possible, or else run a path search for
505 a program that accepts as long a line as possible.
508 New macro that tests for a sed program that truncates as few characters
511 * Major changes in Autoconf 2.59
513 Released 2003-11-04, by Akim Demaille
515 ** ac_abs_builddir etc.
516 Absolute file names were actually relative in 2.58.
518 * Major changes in Autoconf 2.58
520 Released 2003-11-04, by Akim Demaille
523 core.* files are no longer removed, as they may be valid user files.
525 ** autoreconf and auxiliary directory
526 Autoreconf creates the auxiliary directory if needed. This is
527 especially useful for initial "bootstrapping" of fresh CVS checkouts.
529 ** AC_CONFIG_MACRO_DIR
530 Use this macro to declare the directory for local M4 macros for aclocal.
533 No longer includes twice the same file in LIBOBJS if invoked
536 ** AC_CONFIG_COMMANDS
537 The directory for its first argument is automatically created. For
540 AC_CONFIG_COMMANDS([src/modules.hh], [...])
542 $top_builddir/src/ is created if needed.
544 ** Autotest and local.at
545 The optional file local.at is always included in Autotest test suites.
548 The warnings are always issued, including with cached runs.
549 This became a significant problem since aclocal and automake can
550 run autoconf behind the scene.
552 ** autoheader warnings
553 The warnings of autoheader can be turned off, using --warning.
554 For instance, -Wno-obsolete disables the complaints about acconfig.h
555 and other deprecated constructs.
558 AC_C_RESTRICT, AC_INCLUDES_DEFAULT, AC_LANG_ASSERT, AC_LANG_WERROR,
561 ** AC_DECL_SYS_SIGLIST
565 Now checks that mktime is the inverse of localtime.
567 ** Improve DJGPP portability
568 The Autoconf tools and configure behave better under DJGPP.
570 ** Present But Cannot Be Compiled
571 New FAQ section dedicated to the mystic
573 configure: WARNING: pi.h: present but cannot be compiled
574 configure: WARNING: pi.h: check for missing prerequisite headers?
575 configure: WARNING: pi.h: proceeding with the preprocessor's result
578 ** Concurrent executions of autom4te
579 autom4te now locks its internal files, which enables concurrent
580 executions of autom4te, likely to happen if automake, autoconf,
581 autoheader etc. are run simultaneously.
584 Use of Libtool 1.5 and higher is encouraged. Compatibility with
585 Libtool pre-1.4 is not checked.
588 Testsuites no longer rerun failed tests in verbose mode; instead,
589 failures are logged while the test is run.
591 In addition, expected failures can be marked as such.
593 * Major changes in Autoconf 2.57
595 Released 2002-12-03 by Paul Eggert.
597 Bug fixes for problems with AIX linker, with freestanding C compilers,
598 with GNU M4 limitations, and with obsolete copies of GNU documents.
600 The Free Documentation License has been upgraded from 1.1 to 1.2.
602 * Major changes in Autoconf 2.56
604 Released 2002-11-15 by Akim Demaille.
606 One packaging problem fixed (config/install-sh was not executable).
608 * Major changes in Autoconf 2.55
610 Released 2002-11-14 by Akim Demaille.
614 Have your configure.ac checked by autoscan ("autoscan").
615 Try the warning options ("autoreconf -fv -Wall").
619 - AC_CHECK_HEADER, AC_CHECK_HEADERS
620 More information on proper use.
622 - Writing Test Programs
624 This sections explains how to write good test sources to use with
625 AC_COMPILE_IFELSE etc. It documents AC_LANG_PROGRAM and so forth.
627 - AC_FOO_IFELSE vs. AC_TRY_FOO
629 Explains why Autoconf moves from AC_TRY_COMPILE etc. to
630 AC_COMPILE_IFELSE and AC_LANG_PROGRAM etc.
634 - Is more robust to different Gettext installations.
636 - Produces messages (when --verbose) to be understood by Emacs'
639 - Supports -W/--warnings.
642 Once the GNU Build System reinstalled, run `./config.status
643 --recheck && ./config.status && make' if possible.
647 - Supports --cache, and --no-cache.
649 - ~/.autom4te.cfg makes it possible to disable the caching mechanism
650 (autom4te.cache). See `Customizing autom4te' in the documentation.
657 Support for the obsoleted options -m, --macrodir, -l, --localdir is
658 dropped in favor of the safer --include/--prepend-include scheme.
663 AC_COMPILER_IFELSE, AC_FUNC_MBRTOWC, AC_HEADER_STDBOOL,
664 AC_LANG_CONFTEST, AC_LANG_SOURCE, AC_LANG_PROGRAM, AC_LANG_CALL,
665 AC_LANG_FUNC_TRY_LINK, AC_MSG_FAILURE, AC_PREPROC_IFELSE.
668 Obsoleted macros are kept for Autoconf backward compatibility, but
669 should be avoided in configure.ac. Running autoupdate is advised.
672 - AC_DEFINE/AC_DEFINE_UNQUOTED
674 We have to stop using the old compatibility scheme --that tried to
675 avoid useless backslashes-- because Libtool 1.4.3 contains a
677 AC_DEFINE([error_t], [int],
678 [Define to a type to use for \`error_t' if it is not
679 otherwise available.])
681 We have to quote the single quotes and backslashes with \. The old
682 compatibility scheme saw that ` was backslashed, and therefore did
683 not quote the single quote... Failure. Hence, Autoconf 2.54 is not
684 compatible with Libtool. Autoconf 2.55 is, but in some cases might
685 produce more \ than wanted.
687 Please, note that in the future the same problem will happen with
688 AC_MSG_*: use `autoreconf -f -Wall'.
692 - Portability of the Autoconf package to Solaris.
694 - Spurious warnings caused by config.status.
695 This bug is benign, but painful: on some systems (typically
696 FreeBSD), warnings such as:
698 config.status: creating Makefile
699 mv: Makefile: set owner/group (was: 1357/0): Operation not permitted
701 could be issued. This is fixed.
704 Simultaneous executions of config.status are possible again.
706 - Precious variables accumulation
708 config.status could stack several copies of the precious variables
712 ** Plans for later versions
716 The compatibility hooks with the old scheme will be completely
717 removed. Please, advice/use `--build', `--host', and `--target'
720 - AC_CHECK_HEADER, AC_CHECK_HEADERS
722 The tests will be stricter, please make sure your invocations are
727 Shell functions will gradually be introduced, probably starting with
728 Autotest. If you know machines which are in use that you suspect
729 *not* to support shell functions, please run the test suite of
730 Autoconf 2.55 on it, and report the results to
731 bug-autoconf@gnu.org.
735 Special characters in AC_MSG_* need not be quoted. Currently,
736 Autoconf has heuristics to decide when a string is escaped, or has
737 to be escaped. This scheme is fragile, and will be removed; the
738 only risk is uglified messages. Please, run `autoreconf -f -Wall'
739 to find occurrences that will be affected.
741 * Major changes in Autoconf 2.54
743 Released 2002-09-13 by Akim Demaille.
747 - autoreconf no longer changes the version of the gettext/po/intl
748 support files. It now adds the files the correspond to the
749 AM_GNU_GETTEXT_VERSION declared in configure.ac.
751 Warning: It now relies on the 'autopoint' program, which is part
752 of GNU gettext 0.11.4 and newer.
754 Please note that you need to have a GNU gettext version that
755 corresponds at least to the AM_GNU_GETTEXT_VERSION declared
756 in configure.ac. You can upgrade to newer GNU gettext versions,
757 though, without needing to change configure.ac.
759 - The -I DIR or --include=DIR option now appends DIR to the include path
760 instead of prepending; this is for consistency with other GNU tools.
761 The new -B DIR or --prepend-include=DIR option has the old behavior.
766 Now handles all the gory details about LIBOBJS and LTLIBOBJS.
767 Please, remove lines such as
769 # This is necessary so that .o files in LIBOBJS are also
770 # built via the ANSI2KNR-filtering rules.
771 LIBOBJS=`echo $LIBOBJS|sed 's/\.o /\$U.o /g;s/\.o$/\$U.o/'`
773 and read the `AC_LIBOBJ vs LIBOBJS' section. Do not define U in
774 your Makefiles either.
776 - AC_CONFIG_LINKS now makes copies if it can't make links.
778 - AC_FUNC_FNMATCH now tests only for POSIX compatibility, reverting to
779 Autoconf 2.13 behavior. The new macro AC_FUNC_FNMATCH_GNU also
780 tests for GNU extensions to fnmatch, and replaces fnmatch if needed.
782 - AC_FUNC_SETVBUF_REVERSED no longer fails when cross-compiling.
784 - AC_PROG_CC_STDC is integrated into AC_PROG_CC.
786 - AC_PROG_F77 default search no longer includes cf77 and cfg77.
790 AC_C_BACKSLASH_A, AC_CONFIG_LIBOBJ_DIR, AC_GNU_SOURCE,
791 AC_PROG_EGREP, AC_PROG_FGREP, AC_REPLACE_FNMATCH,
792 AC_FUNC_FNMATCH_GNU, AC_FUNC_REALLOC, AC_TYPE_MBSTATE_T.
795 looks for getloadavg.c in the CONFIG_LIBOBJ_DIR.
798 Now defines HAVE_MALLOC to 0 if `malloc' does not work, and asks
799 for an AC_LIBOBJ replacement.
803 - Spurious complaints from `m4_bmatch' about invalid regular
804 expressions are suppressed.
806 - Empty top_builddirs are properly handled.
808 - AC_CHECK_MEMBER works correctly when the member is an aggregate.
811 Now colon in the optional path arguments are properly handled.
813 ** Improved portability
815 - Both Autoconf the package, and the scripts it produces, should run
816 more reliably with Zsh. Bear in mind it is the default Bourne shell
819 - Autoconf and the scripts it produces no longer assume the existence of
820 the obsolescent commands egrep and fgrep.
824 - Limitations of Make
828 The GNATS base moved to
829 http://bugs.gnu.org/cgi-bin/gnatsweb.pl?database=autoconf
830 (It is no longer available, though.)
835 Now contains the list of ouput variables and files (AC_SUBST,
838 * Major changes in Autoconf 2.53
840 Released 2002-03-08 by Akim Demaille.
844 Perl 5.005_03 or later is required: autom4te is written in Perl and is
845 needed by autoconf. autoheader, autoreconf, ifnames, and autoscan are
851 Argument requirements, output variables, defined macros.
852 - M4sugar, M4sh, Autotest
854 - Double quoting macros
855 AC_TRY_CPP, AC_TRY_COMPILE, AC_TRY_LINK and AC_TRY_RUN.
857 The Autoconf manual is now distributed under the terms of the GNU FDL.
858 - Section `Hosts and Cross-Compilation'
859 Explains the rationale for the 2.5x changes in the cross-compilation
860 chain, and in the relationships between build, host, and target
862 Emphasizes that `cross-compilation' == `--host is given'.
863 If you are working on compilers etc., be sure to read this section.
864 - Section `AC_LIBOBJ vs. LIBOBJS'
865 Explains why assigning LIBOBJS directly is now an error.
866 Details how to update the code.
871 Now used instead of hard coded line numbers.
872 This eases the comparison of `configure's, and diminishes the
873 pressure over control version archives.
874 Automatic replacement for shells that don't support this feature.
875 - New output variables
876 @builddir@, @top_builddir@, @abs_srcdir@, @abs_top_srcdir@, @abs_builddir@,
881 Autoconf and Autotest modes are provided.
886 New, used by the Autoconf suite to cache and speed up most processing.
888 Supported by autom4te, autoconf and autoheader.
890 Replaces --autoconf-dir and --localdir in autoconf, autoheader,
891 autoupdate, and autoreconf.
893 No longer passes --cygnus, --foreign, --gnits, --gnu, --include-deps:
894 automake options are to be given via AUTOMAKE_OPTIONS.
896 Runs gettextize and libtoolize when appropriate.
898 --m4dir is no longer supported.
900 Now runs only in the specified directories, defaulting to `.',
901 but understands AC_CONFIG_SUBDIRS for dependent directories.
902 Before, it used to run on all the `configure.ac' found in the
904 Independent packages are properly updated.
908 - The top level $prefix is propagated to the AC_CONFIG_SUBDIRS configures.
910 Under the user pressure, $? is finally available. Probably a mistake.
911 - AC_F77_LIBRARY_LDFLAGS now supports the HP/UX f90 compiler.
912 - Precious variables accumulation
913 config.status could stack several copies of the precious variables
915 - AC_PATH_PROG and family.
916 Works properly when given a literal path.
918 Somewhere since 2.13, the result had been reversed.
922 - AC_C_BIGENDIAN supports the cross-compiling case.
923 - AC_C_BIGENDIAN accepts ACTION-IF-TRUE, ACTION-IF-FALSE, and
924 ACTION-IF-UNKNOWN arguments. All are facultative, and the default
925 for ACTION-IF-TRUE is to define WORDS_BIGENDIAN like AC_C_BIGENDIAN
927 - AC_C_LONG_DOUBLE now succeeds only if `long double' has more range or
928 precision than `double'.
933 It now defines the preprocessor symbols PACKAGE_NAME,
934 PACKAGE_TARNAME, PACKAGE_VERSION, PACKAGE_STRING, and
938 Admits a fourth optional parameter: the tar name.
940 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS.
941 Provide the user with srcdir, ac_srcdir, ac_top_srcdir, ac_builddir,
942 ac_top_builddir, ac_abs_srcdir, ac_abs_top_srcdir, ac_abs_builddir,
945 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS and AC_OUTPUT.
946 Are much less expensive when using long lists of files.
949 Works with shell variables, and non alphanumeric names.
953 - AC_FUNC_STRERROR_R now sets STRERROR_R_CHAR_P, not HAVE_WORKING_STRERROR_R,
954 because POSIX 1003.1-200x draft 7 says strerror_r returns int, not char *.
956 - AC_FUNC_STRTOD substitutes POW_LIB.
961 * Major changes in Autoconf 2.52
963 Released 2001-07-18 by Akim Demaille.
968 This feature was present in autoconf 2.50 but was not documented.
969 For example, `@<:@' is translated to `[' just before output. This
970 is useful when writing strings that contain unbalanced quotes, or
971 other hard-to-quote constructs.
972 - m4_pattern_forbid, m4_pattern_allow
973 - Tips for upgrading from 2.13.
974 - Using autoscan to maintain a configure.ac.
977 - Now include stdint.h.
978 - sys/types.h and sys/stat.h are guarded.
979 - strings.h is included if available, and not conflicting with string.h.
982 - The test suite is more robust and presents less false failures.
983 - Invocation of GNU M4 now robust to POSIXLY_CORRECT.
984 - configure accepts --prefix='' again.
985 - AC_CHECK_LIB works properly when its first argument is not a
987 - HAVE_INTTYPES_H is defined only if not conflicting with sys/types.h.
988 - build_, host_, and target_alias are AC_SUBST as in 2.13.
989 - AC_ARG_VAR properly propagates precious variables inherited from the
990 environment to ./config.status.
991 - Using --program-suffix/--program-prefix is portable.
992 - Failures to detect the default compiler's output extension are less
994 - `config.status foo' works properly when `foo' depends on variables
995 set in an AC_CONFIG_THING INIT-CMD.
996 - autoheader is more robust to broken input.
997 - Fixed Fortran name-mangling and link tests on a number of systems,
998 e.g. NetBSD; see AC_F77_DUMMY_MAIN, below.
1001 - AC_CHECK_HEADER and AC_CHECK_HEADERS support a fourth argument to
1002 specify pre-includes. In this case, the headers are compiled with
1003 cc, not merely preprocessed by cpp. Therefore it is the _usability_
1004 of a header which is checked for, not just its availability.
1005 - AC_ARG_VAR refuses to run configure when precious variables have
1007 - Versions of compilers are dumped in the logs.
1008 - AC_CHECK_TYPE recognizes use of `foo_t' as a replacement type.
1011 - AC_PATH_XTRA only adds -ldnet to $LIBS if it's needed to link.
1012 - AC_FUNC_WAIT3 and AC_SYS_RESTARTABLE_SYSCALLS are obsoleted.
1013 - AM_FUNC_ERROR_AT_LINE, AM_FUNC_FNMATCH, AM_FUNC_MKTIME,
1014 AM_FUNC_OBSTACK, and AM_FUNC_STRTOD are now activated.
1015 Be sure to read `Upgrading from Version 2.13' to understand why
1016 running `autoupdate' is needed.
1017 - AC_F77_DUMMY_MAIN, AC_F77_MAIN: new macros to detect whether
1018 a main-like routine is required/possible when linking C/C++ with
1019 Fortran. Users of e.g. AC_F77_WRAPPERS should be aware of these.
1020 - AC_FUNC_GETPGRG behaves better when cross-compiling.
1022 * Major changes in Autoconf 2.51
1023 There was no release of Autoconf 2.51 since some packagers had used
1024 this version number without permission to ship intermediary versions
1025 of 2.50. The version was skipped to avoid confusion.
1027 * Major changes in Autoconf 2.50
1029 Released 2001-05-21 by Akim Demaille.
1031 ** Lots of bug fixes
1032 There have been far too many to enumerate them here. Check out
1033 ChangeLog if you really want to know more.
1035 ** Improved documentation
1036 In particular, portability issues are better covered.
1039 All the standard GNU Makefile targets are supported. The layout has
1040 changed: m4/ holds the M4 extensions Autoconf needs for its
1041 configuration, doc/ contains the documentation, and tests/ contains
1044 ** Man pages are provided
1045 For autoconf, autoreconf, autoupdate, autoheader, autoscan, ifnames,
1046 config.guess, config.sub.
1050 Provides a safe and powerful means to trace the macro uses. This
1051 provide the parsing layer for tools which need to `study'
1055 Specify what category of warnings should be enabled.
1057 - When recursing into subdirectories, try for configure.gnu before
1058 configure to adapt for packages not using autoconf on case-insensitive
1062 More errors are now caught (circular AC_REQUIRE dependencies,
1063 AC_DEFINE in the action part of an AC_CACHE_CHECK, too many pops
1064 etc.). In addition, their location and call stack are given.
1067 autoupdate is much more powerful, and is able to provide the glue code
1068 which might be needed to move from an old macro to its newer
1071 You are strongly encouraged to use it to modernize both your
1072 `configure.in' and your .m4 extension files.
1075 The internal machinery of autoheader has completely changed. As a
1076 result, using `acconfig.h' should be considered to be obsoleted, and
1077 you are encouraged to get rid of it using the AH macros.
1082 ** Fortran 77 compilers
1083 Globally, the support for Fortran 77 is considerably improved.
1085 Support for automatically determining a Fortran 77 compiler's
1086 name-mangling scheme. New CPP macros F77_FUNC and F77_FUNC_ are
1087 provided to wrap C/C++ identifiers, thus making it easier and more
1088 transparent for C/C++ to call Fortran 77 routines, and Fortran 77 to
1089 call C/C++ routines. See the Texinfo documentation for details.
1092 The test suite no longer uses DejaGNU. It should be easy to submit
1093 test cases in this new framework.
1096 - --help, --help=long, -hl
1097 no longer dumps useless items.
1099 lists only specific options.
1100 - --help=recursive, -hr
1101 displays the help of all the embedded packages.
1102 - Remembers environment variables when reconfiguring.
1103 The previous scheme to set envvar before running configure was
1105 what prevented configure from remembering the environment in which
1106 it was run, therefore --recheck was run in an inconsistent
1107 environment. Now, one should run
1109 and then --recheck will work properly. Variables declared with
1110 AC_ARG_VAR are also preserved.
1112 $build defaults to `config.guess`, $host to $build, and then $target
1114 Cross-compilation is a global status of the package, it no longer
1115 depends upon the current language.
1116 Cross compilation is enabled iff the user specified `--host'.
1117 `configure' now fails if it can't run the executables it compiles,
1118 unless cross-compilation is enabled.
1120 The cache file is disabled by default. The new options
1121 `--config-cache', `-C' set the cache to `config.cache'.
1125 Much faster on most architectures.
1126 - concurrent executions
1127 It is safe to use `make -j' with config.status.
1128 - human interface improved
1129 It is possible to invoke
1130 ./config.status foobar
1131 instead of the former form (still valid)
1132 CONFIG_COMMANDS= CONFIG_HEADERS= CONFIG_LINKS= \
1133 CONFIG_FILES=foobar:foo.in:bar.in \
1135 The same holds for configuration headers and links.
1136 You can instantiate unknown files and headers:
1137 ./config.status --header foo.h:foo.h.in --file bar:baz
1138 - has a useful --help
1139 - accepts special file name "-" for stdin/stdout
1144 Specify additional copyright information.
1147 Now expects the identity of the package as argument.
1151 Most macros, if not all, now strictly follow the `one quotation
1152 level' rule. This results in a more predictable expansion.
1155 A sly bug in the AC_REQUIRE machinery, which could produce incorrect
1156 configure scripts, was fixed by Axel Thimm.
1160 Document and ask for the registration of an envvar.
1163 Specifies the file which `configure' should look for when trying to
1164 find the source tree (used to be handled by AC_INIT).
1166 - AC_CONFIG_COMMANDS
1167 To add new actions to config.status. Should be used instead of
1171 Replaces AC_LINK_FILES.
1173 - AC_CONFIG_HEADERS, AC_CONFIG_COMMANDS, AC_CONFIG_SUBDIRS,
1174 AC_CONFIG_LINKS, and AC_CONFIG_FILES
1175 They now obey sh: you should no longer use shell variables as
1176 argument. Instead of
1178 test "$package_foo_enabled" = yes && $my_subdirs="$my_subdirs foo"
1179 AC_CONFIG_SUBDIRS($my_subdirs)
1183 if test "$package_foo_enabled" = yes; then
1184 AC_CONFIG_SUBDIRS(foo)
1188 To format an Autoconf macro's help string so that it looks pretty
1189 when the user executes `configure --help'.
1192 ** Generic Test Macros
1194 The interface of the AC_CHECK families of macros (decl, header,
1195 type, member, func) is now uniform. They support the same set of
1198 - AC_CHECK_DECL, AC_CHECK_DECLS
1199 To check whether a symbol is declared.
1201 - AC_CHECK_SIZEOF, AC_C_CHAR_UNSIGNED.
1202 No longer need a cross-compilation default.
1205 The test it performs is much more robust than previously, and makes
1206 it possible to test builtin types in addition to typedefs.
1207 It is now schizophrenic:
1208 - AC_CHECK_TYPE(TYPE, REPLACEMENT)
1209 remains for backward compatibility, but its use is discouraged.
1210 - AC_CHECK_TYPE(TYPE, IF-FOUND, IF-NOT-FOUND, INCLUDES)
1211 behaves exactly like the other AC_CHECK macros.
1214 Checks whether given types are supported by the system.
1216 - AC_CHECK_MEMBER, AC_CHECK_MEMBERS
1217 Check for given members in aggregates (e.g., pw_gecos in struct
1221 Checks if the compiler supports ISO C, included when needs special
1225 Checking whether the preprocessor indicates missing includes by the
1226 error code. stderr is checked by AC_TRY_CPP only as a fallback.
1229 Takes a language as argument and replaces AC_LANG_C,
1230 AC_LANG_CPLUSPLUS and AC_LANG_FORTRAN77.
1232 - AC_LANG_PUSH, AC_LANG_POP
1233 Are preferred to AC_LANG_SAVE, AC_LANG_RESTORE.
1236 - AC_FUNC_CHOWN, AC_FUNC_MALLOC, AC_FUNC_STRERROR_R,
1237 AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK, AC_FUNC_STAT, AC_FUNC_LSTAT,
1238 AC_FUNC_ERROR_AT_LINE, AC_FUNC_OBSTACK, AC_FUNC_STRTOD, AC_FUNC_FSEEKO.
1242 Sets GETGROUPS_LIBS.
1244 - AC_FUNC_GETLOADAVG
1245 Defines `HAVE_STRUCT_NLIST_N_UN_N_NAME' instead of `NLIST_NAME_UNION'.
1248 Now integrates `AC_DECL_YYTEXT' which is obsoleted.
1251 Arrange for large-file support.
1253 - AC_EXEEXT, AC_OBJEXT
1254 You are no longer expected to use them: their computation is
1255 performed by default.
1257 ** C++ compatibility
1258 Every macro has been revisited in order to support at best CC=c++.
1260 Major changes in Autoconf 2.14:
1261 There was no release of GNU Autoconf 2.14.
1263 Major changes in Autoconf 2.13:
1265 Released 1999-05-01 by Ben Elliston.
1267 * Support for building on Win32 systems where the only available C or
1268 C++ compiler is the Microsoft Visual C++ command line compiler
1269 (`cl'). Additional support for building on Win32 systems which are
1270 using the Cygwin or Mingw32 environments.
1271 * Support for alternative object file and executable file extensions.
1272 On Win32, for example, these are .obj and .exe. These are discovered
1273 using AC_OBJEXT and AC_EXEEXT, which substitute @OBJEXT@ and
1274 @EXEEXT@ in the output, respectively.
1275 * New macros: AC_CACHE_LOAD, AC_CACHE_SAVE, AC_FUNC_SELECT_ARGTYPES,
1276 AC_VALIDATE_CACHED_SYSTEM_TUPLE, AC_SEARCH_LIBS, AC_TRY_LINK_FUNC,
1277 AC_C_STRINGIZE, AC_CHECK_FILE(S), AC_PROG_F77 (and friends).
1278 * AC_DEFINE now has an optional third argument for a description to be
1279 placed in the config header input file (e.g. config.h.in).
1280 * The C++ code fragment compiled for the C++ compiler test had to be
1281 improved to include an explicit return type for main(). This was
1282 causing failures on systems using recent versions of the EGCS C++
1284 * Fixed an important bug in AC_CHECK_TYPE that would cause a configure
1285 script to report that `sometype_t' was present when only `type_t'
1287 * Merge of the FSF version of config.guess and config.sub to modernize
1288 these scripts. Add support for a few new hosts in config.guess.
1289 Incorporate latest versions of install-sh, mkinstalldirs and
1290 texinfo.tex from the FSF.
1291 * autoreconf is capable of running automake if necessary (and
1293 * Support for Fortran 77. See the Texinfo documentation for details.
1294 * Bug fixes and workarounds for quirky bugs in vendor utilities.
1296 Major changes in Autoconf 2.12:
1298 Released 1996-11-26 by David J. MacKenzie
1300 * AC_OUTPUT and AC_CONFIG_HEADER can create output files by
1301 concatenating multiple input files separated by colons, like so:
1302 AC_CONFIG_HEADER(config.h:conf.pre:config.h.in:conf.post)
1303 AC_OUTPUT(Makefile:Makefile.in:Makefile.rules)
1304 The arguments may be shell variables, to compute the lists on the fly.
1305 * AC_LINK_FILES and AC_CONFIG_SUBDIRS may be called multiple times.
1306 * New macro AC_OUTPUT_COMMANDS adds more commands to run in config.status.
1309 Major changes in Autoconf 2.11:
1311 Released November 18th, 1996, by David J. MacKenzie
1313 * AC_PROG_CC and AC_PROG_CXX check whether the compiler works.
1314 They also default CFLAGS/CXXFLAGS to "-g -O2" for gcc, instead of "-g -O".
1315 * AC_REPLACE_FUNCS defines HAVE_foo if the system has the function `foo'.
1316 * AC_CONFIG_HEADER expands shell variables in its argument.
1317 * New macros: AC_FUNC_FNMATCH, AC_FUNC_SETPGRP.
1318 * The "checking..." messages and the source code for test programs that
1319 fail are saved in config.log.
1320 * Another workaround has been added for seds with small command length limits.
1321 * config.sub and config.guess recognize more system types.
1324 Major changes in Autoconf 2.10:
1326 Released May 7th, 1996, by Roland McGrath
1329 * The cache variable names used by `AC_CHECK_LIB(LIB, FUNC, ...)' has
1330 changed: now $ac_cv_lib_LIB_FUNC, previously $ac_cv_lib_LIB.
1332 Major changes in Autoconf 2.9:
1334 Released March 16th, 1996, by Roland McGrath
1338 Major changes in Autoconf 2.8:
1340 Released March 8th, 1996, by Roland McGrath
1344 Major changes in Autoconf 2.7:
1346 Released November 22nd, 1995, by David J. MacKenzie
1350 Major changes in Autoconf 2.6:
1352 Released November 20th, 1995, by David J. MacKenzie
1356 Major changes in Autoconf 2.5:
1358 Released November 17th, 1995, by Roland McGrath
1360 * New configure options --bindir, --libdir, --datadir, etc., with
1361 corresponding output variables.
1362 * New macro: AC_CACHE_CHECK, to make using the cache easier.
1363 * config.log contains the command being run as well as any output from it.
1364 * AC_CHECK_LIB can check for libraries with "." or "/" or "+" in their name.
1365 * AC_PROG_INSTALL doesn't cache a name for install-sh, for sharing caches.
1366 * AC_CHECK_PROG, AC_PATH_PROG, AC_CHECK_PROGS, AC_PATH_PROGS, and
1367 AC_CHECK_TOOL can search a path other than $PATH.
1368 * AC_CHECK_SIZEOF takes an optional size to use when cross-compiling.
1370 Major changes in Autoconf 2.4:
1372 Released June 14th, 1995, by David J. MacKenzie
1374 * Fix a few bugs found by Emacs testers.
1376 Major changes in Autoconf 2.3:
1378 Released March 27th, 1995, by David J. MacKenzie
1380 * Fix the cleanup trap in several ways.
1381 * Handle C compilers that are picky about option placement.
1382 * ifnames gets the version number from the right directory.
1384 Major changes in Autoconf 2.2:
1386 Released March 8th, 1995, by David J. MacKenzie
1388 * The ifnames utility is much faster but requires a "new awk" interpreter.
1389 * AC_CHECK_LIB and AC_HAVE_LIBRARY check and add the new
1390 library before existing libs, not after, in case it uses them.
1391 * New macros: AC_FUNC_GETPGRP, AC_CHECK_TOOL.
1392 * Lots of bug fixes.
1393 * Many additions to the TODO file :-)
1395 Major changes in Autoconf 2.1:
1397 Released November 4th, 1994, by David J. MacKenzie
1400 * More explanations in the manual.
1401 * Fix a spurious failure in the testsuite.
1402 * Clarify some warning messages.
1403 * autoreconf by default only rebuilds configure and config.h.in files
1404 that are older than any of their particular input files; there is a
1405 --force option to use after installing a new version of Autoconf.
1407 Thanks to everybody who's submitted changes and additions to Autoconf!
1408 I've incorporated many of them, and am still considering others for
1409 future releases -- but I didn't want to postpone this release indefinitely.
1411 Caution: don't indiscriminately rebuild configure scripts with
1412 Autoconf version 2. Some configure.in files need minor adjustments to
1413 work with it; the documentation has a chapter on upgrading. A few
1414 configure.in files, including those for GNU Emacs and the GNU C
1415 Library, need major changes because they relied on undocumented
1416 internals of version 1. Future releases of those packages will have
1417 updated configure.in files.
1419 It's best to use GNU M4 1.3 (or later) with Autoconf version 2.
1420 Autoconf now makes heavy use of M4 diversions, which were implemented
1421 inefficiently in GNU M4 releases before 1.3.
1423 Major changes in Autoconf 2.0:
1425 Released October 26th, 1994, by David J. MacKenzie
1427 ** New copyright terms:
1428 * There are no restrictions on distribution or use of configure scripts.
1431 * Autoconf manual is reorganized to make information easier to find
1432 and has several new indexes.
1433 * INSTALL is reorganized and clearer and is now made from Texinfo source.
1436 * autoscan to generate a preliminary configure.in for a package by
1437 scanning its source code for commonly used nonportable functions,
1438 programs, and header files.
1439 * ifnames to list the symbols used in #if and #ifdef directives in a
1441 * autoupdate to update a configure.in to use the version 2 macro names.
1442 * autoreconf to recursively remake configure and configuration header
1443 files in a source tree.
1445 ** Changed utilities:
1446 * autoheader can take pieces of acconfig.h to replace config.h.{top,bot}.
1447 * autoconf and autoheader can look for package-local definition files
1448 in an alternate directory.
1451 * AC_CACHE_VAL to share results of tests between configure runs.
1452 * AC_DEFUN to define macros, automatically AC_PROVIDE them, and ensure
1453 that macros invoked with AC_REQUIRE don't interrupt other macros.
1454 * AC_CONFIG_AUX_DIR, AC_CANONICAL_SYSTEM, AC_CANONICAL_HOST, AC_LINK_FILES to
1455 support deciding unguessable features based on the host and target types.
1456 * AC_CONFIG_SUBDIRS to recursively configure a source tree.
1457 * AC_ARG_PROGRAM to use the options --program-prefix,
1458 --program-suffix, and --program-transform-name to change the names
1459 of programs being installed.
1460 * AC_PREFIX_DEFAULT to change the default installation prefix.
1461 * AC_TRY_COMPILE to compile a test program without linking it.
1462 * AC_CHECK_TYPE to check whether sys/types.h or stdlib.h defines a given type.
1463 * AC_CHECK_LIB to check for a particular function and library.
1464 * AC_MSG_CHECKING and AC_MSG_RESULT to print test results, on a single line,
1465 whether or not the test succeeds. They obsolete AC_CHECKING and AC_VERBOSE.
1466 * AC_SUBST_FILE to insert one file into another.
1467 * AC_FUNC_MEMCMP to check whether memcmp is 8-bit clean.
1468 * AC_FUNC_STRFTIME to find strftime even if it's in -lintl.
1469 * AC_FUNC_GETMNTENT to find getmntent even if it's in -lsun or -lseq.
1470 * AC_HEADER_SYS_WAIT to check whether sys/wait.h is POSIX.1 compatible.
1473 * Many macros renamed systematically, but old names are accepted for
1474 backward compatibility.
1475 * AC_OUTPUT adds the "automatically generated" comment to
1476 non-Makefiles where it finds @configure_input@ in an input file, to
1477 support files with various comment syntaxes.
1478 * AC_OUTPUT does not replace "prefix" and "exec_prefix" in generated
1479 files when they are not enclosed in @ signs.
1480 * AC_OUTPUT allows the optional environment variable CONFIG_STATUS to
1481 override the file name "config.status".
1482 * AC_OUTPUT takes an optional argument for passing variables from
1483 configure to config.status.
1484 * AC_OUTPUT and AC_CONFIG_HEADER allow you to override the input-file names.
1485 * AC_OUTPUT automatically substitutes the values of CFLAGS, CXXFLAGS,
1486 CPPFLAGS, and LDFLAGS from the environment.
1487 * AC_PROG_CC and AC_PROG_CXX now set CFLAGS and CXXFLAGS, respectively.
1488 * AC_PROG_INSTALL looks for install-sh or install.sh in the directory
1489 specified by AC_CONFIG_AUXDIR, or srcdir or srcdir/.. or
1490 srcdir/../.. by default.
1491 * AC_DEFINE, AC_DEFINE_UNQUOTED, and AC_SUBST are more robust and smaller.
1492 * AC_DEFINE no longer prints anything, because of the new result reporting
1493 mechanism (AC_MSG_CHECKING and AC_MSG_RESULT).
1494 * AC_VERBOSE pays attention to --quiet/--silent, not --verbose.
1495 * AC_ARG_ENABLE and AC_ARG_WITH support whitespace in the arguments to
1496 --enable- and --with- options.
1497 * AC_CHECK_FUNCS and AC_CHECK_HEADERS take optional shell commands to
1498 execute on success or failure.
1499 * Checking for C functions in C++ works.
1502 * AC_REMOTE_TAPE and AC_RSH removed; too specific to tar and cpio, and
1503 better maintained with them.
1504 * AC_ARG_ARRAY removed because no one was likely using it.
1505 * AC_HAVE_POUNDBANG replaced with AC_SYS_INTERPRETER, which doesn't
1506 take arguments, for consistency with all of the other specific checks.
1509 * Comes with config.sub and config.guess, and uses them optionally.
1510 * Uses config.cache to cache test results. An alternate cache file
1511 can be selected with the --cache-file=FILE option.
1512 * Uses optional shell scripts $prefix/share/config.site and
1513 $prefix/etc/config.site to perform site or system specific initializations.
1514 * configure saves compiler output to ./config.log for debugging.
1515 * New files autoconf.m4 and autoheader.m4 load the other Autoconf macros.
1516 * acsite.m4 is the new name for the system-wide aclocal.m4.
1517 * Has a DejaGnu test suite.
1519 Major changes in Autoconf 1.11:
1521 * AC_PROG_INSTALL calls install.sh with the -c option.
1522 * AC_SET_MAKE cleans up after itself.
1523 * AC_OUTPUT sets prefix and exec_prefix if they weren't set already.
1524 * AC_OUTPUT prevents shells from looking in PATH for config.status.
1526 Plus a few other bug fixes.
1528 Major changes in Autoconf 1.10:
1530 * autoheader uses config.h.bot if present, analogous to config.h.top.
1531 * AC_PROG_INSTALL looks for install.sh in srcdir or srcdir/.. and
1533 * AC_PROG_CXX looks for cxx as a C++ compiler.
1535 Plus several bugs fixed.
1537 Major changes in Autoconf 1.9:
1539 * AC_YYTEXT_POINTER replaces AC_DECLARE_YYTEXT.
1540 * AC_SIZEOF_TYPE generates the cpp symbol name automatically,
1541 and autoheader generates entries for those names automatically.
1542 * AC_FIND_X gets the result from xmkmf correctly.
1543 * AC_FIND_X assumes no X if --without-x was given.
1544 * AC_FIND_XTRA adds libraries to the variable X_EXTRA_LIBS.
1545 * AC_PROG_INSTALL finds OSF/1 installbsd.
1547 Major changes in Autoconf 1.8:
1550 * New macros AC_LANG_C, AC_LANG_CPLUSPLUS, AC_LANG_SAVE, AC_LANG_RESTORE,
1551 AC_PROG_CXX, AC_PROG_CXXCPP, AC_REQUIRE_CPP
1552 for checking both C++ and C features in one configure script.
1553 * New macros AC_CHECKING, AC_VERBOSE, AC_WARN, AC_ERROR for printing messages.
1554 * New macros AC_FIND_XTRA, AC_MMAP, AC_SIZEOF_TYPE, AC_PREREQ,
1555 AC_SET_MAKE, AC_ENABLE.
1558 * AC_FIND_X looks for X in more places.
1559 * AC_PROG_INSTALL defaults to install.sh instead of cp, if it's in srcdir.
1560 install.sh is distributed with Autoconf.
1561 * AC_DECLARE_YYTEXT has been removed because it can't work, pending
1562 a rewrite of quoting in AC_DEFINE.
1563 * AC_OUTPUT adds its comments in C format when substituting in C files.
1564 * AC_COMPILE_CHECK protects its ECHO-TEXT argument with double quotes.
1566 ** New or changed command line options:
1567 * configure accepts --enable-FEATURE[=ARG] and --disable-FEATURE options.
1568 * configure accepts --without-PACKAGE, which sets withval=no.
1569 * configure accepts --x-includes=DIR and --x-libraries=DIR.
1570 * Giving --with-PACKAGE no argument sets withval=yes instead of withval=1.
1571 * configure accepts --help, --version, --silent/--quiet, --no-create options.
1572 * configure accepts and ignores most other Cygnus configure options, and
1573 warns about unknown options.
1574 * config.status accepts --help, --version options.
1576 ** File names and other changes:
1577 * Relative srcdir values are not made absolute.
1578 * The values of @prefix@ and @exec_prefix@ and @top_srcdir@ get substituted.
1579 * Autoconf library files are installed in ${datadir}/autoconf, not ${datadir}.
1580 * autoheader optionally copies config.h.top to the beginning of config.h.in.
1581 * The example Makefile dependencies for configure et al. work better.
1582 * Namespace cleanup: all shell variables used internally by Autoconf
1583 have names beginning with `ac_'.
1585 More big improvements are in process for future releases, but have not
1586 yet been (variously) finished, integrated, tested, or documented enough
1589 Major changes in Autoconf 1.7:
1591 * New macro AC_OBSOLETE.
1592 * Bugs in Makefile.in fixed.
1593 * AC_LONG_FILE_NAMES improved.
1595 Major changes in Autoconf 1.6:
1597 * New macro AC_LONG_64_BITS.
1598 * Multiple .h files can be created.
1599 * AC_FIND_X looks for X files directly if it doesn't find xmkmf.
1600 * AC_ALLOCA defines C_ALLOCA if using alloca.c.
1601 * --with-NAME can take a value, e.g., --with-targets=sun4,hp300bsd.
1602 * Unused --no-create option to configure removed.
1603 * autoheader doesn't change the timestamp of its output file if
1604 the file didn't change.
1605 * All macros that look for libraries now use AC_HAVE_LIBRARY.
1606 * config.status checks three optional environment variables to
1607 modify its behavior.
1608 * The usual bug fixes.
1610 Major changes in Autoconf 1.5:
1612 * New macros AC_FIND_X, AC_OFF_T, AC_STAT_MACROS_BROKEN, AC_REVISION.
1613 * autoconf and autoheader scripts have GNU standards conforming
1614 --version and --help options (they print their message and exit).
1617 Major changes in Autoconf 1.4:
1619 * New macros AC_HAVE_POUNDBANG, AC_TIME_WITH_SYS_TIME, AC_LONG_DOUBLE,
1620 AC_GETGROUPS_T, AC_DEFINE_UNQUOTED.
1621 * autoconf and autoheader use the M4 environment variable to determine the
1622 name of the M4 program to use.
1623 * The --macrodir option to autoconf and autoheader specifies the directory
1624 in which acspecific.m4, acgeneral.m4, etc. reside if not the default.
1625 * autoconf and autoheader can take `-' as their file names, which means to
1626 read stdin as input.
1627 * Resulting configure scripts can take a --verbose option which causes them
1628 to print the results of their tests.
1629 * AC_DEFINE quotes its second argument in such a way that spaces, magic
1630 shell characters, etc. will be preserved during various stages of
1631 expansion done by the shell. If you don't want this, use
1632 AC_DEFINE_UNQUOTED instead.
1633 * Much textual processing done with external calls to tr and sed have been
1634 internalized with builtin M4 `patsubst' and `translit' calls.
1635 * AC_OUTPUT doesn't hardwire the file names it outputs. Instead, you can
1636 set the shell variables `gen_files' and `gen_config' to the list of
1637 file names to output.
1638 * AC_DECLARE_YYTEXT does an AC_SUBST of `LEX_OUTPUT_ROOT', which may be
1639 "lex.yy" or "lexyy", depending on the system.
1640 * AC_PROGRAMS_CHECK takes an optional third arg. If given, it is used as
1642 * If AC_ALLOCA chooses alloca.c, it also defines STACK_DIRECTION.
1643 * AC_CONST works much more reliably on more systems.
1646 Major changes in Autoconf 1.3:
1648 configure no longer requires awk for packages that use a config.h.
1649 Support handling --with-PACKAGE options.
1650 New `autoheader' script to create `config.h.in' from `configure.in'.
1651 Ignore troublesome -lucb and -lPW when searching for alloca.
1652 Rename --exec_prefix to --exec-prefix for GNU standards conformance.
1653 Improve detection of STDC library.
1654 Add AC_HAVE_LIBRARY to check for non-default libraries.
1655 Function checking should work with future GNU libc releases.
1657 Major changes in Autoconf 1.2:
1659 The --srcdir option is now usually unnecessary.
1660 Add a file containing sample comments describing CPP macros.
1661 A comment in config.status tells which host it was configured on.
1662 Substituted variable values can now contain commas.
1663 Fix bugs in various feature checks.
1665 Major changes in Autoconf 1.1:
1667 Added AC_STRCOLL macro.
1668 Made AC_GETLOADAVG check for more things.
1669 AC_OUTPUT argument is now optional.
1674 Copyright (C) 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002,
1675 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
1677 This program is free software: you can redistribute it and/or modify
1678 it under the terms of the GNU General Public License as published by
1679 the Free Software Foundation, either version 3 of the License, or
1680 (at your option) any later version.
1682 This program is distributed in the hope that it will be useful,
1683 but WITHOUT ANY WARRANTY; without even the implied warranty of
1684 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1685 GNU General Public License for more details.
1687 You should have received a copy of the GNU General Public License
1688 along with this program. If not, see <http://www.gnu.org/licenses/>.