1 * Major changes in Autoconf 2.60a
3 Released 2006-08-25, by Paul Eggert.
5 ** GNU M4 1.4.6 or later is now recommended. At least one "make check"
6 test fails with earlier versions of M4.
8 ** The check for C99 now tests for varargs macros, as documented.
9 It also tests that the preprocessor supports 64-bit integers.
11 ** Autoconf now uses constructs like "#ifdef HAVE_STDLIB_H" rather than
12 "#if HAVE_STDLIB_H", so that it now works with "gcc -Wundef -Werror".
14 ** The functionality of the undocumented _AC_COMPUTE_INT is now provided
15 by a public and documented macro, AC_COMPUTE_INT. The parameters to the
16 two macros are different, so autoupdate will not change the old private name
17 to the new one. _AC_COMPUTE_INT may be removed in a future release.
19 ** AC_TYPE_LONG_LONG_INT and AC_TYPE_UNSIGNED_LONG_LONG_INT now require
20 that long long types be at least 64 bits wide, as C99 and tradition
21 requires. Formerly, they accepted implementations of any width.
24 * Major changes in Autoconf 2.60
26 Released 2006-06-23, by Ralf Wildenhues.
28 ** Autoconf no longer depends on whether m4wrap is FIFO (as Posix requires)
29 or LIFO (as in GNU M4 1.4.x). GNU M4 2.0 is expected to conform to Posix
30 here, so m4wrap/m4_wrap users should no longer depend on LIFO behavior.
32 ** Provide a way to turn off warnings about the changed directory variables.
34 * Major changes in Autoconf 2.59d
36 Released 2006-06-05, by Ralf Wildenhues.
38 ** GNU make now recommended for VPATH builds
39 INSTALL now suggests VPATH builds (e.g., "sh ../srcdir/configure")
40 only if you use GNU make. In practice, other 'make' implementations
41 have too many subtle incompatibilities in their support for VPATH.
42 Many packages (including Autoconf itself) are portable to other
43 'make' implementations, but some packages are not, and recommending
44 GNU make keeps the installation instructions simpler.
46 ** Even more safety checks for the new Directory variables:
47 Warn about suspicious `${datarootdir}' found in config files output.
49 ** AC_TRY_COMMAND, AC_TRY_EVAL, ac_config_guess, ac_config_sub, ac_configure
50 These never-documented macros and variables have been marked with
51 comments saying that they may be removed in a future release,
52 because their use can lead to unintended code being executed.
53 If you need functionality that only these macros or variables
54 currently supply, please write bug-autoconf@gnu.org.
56 ** AC_SUBST, AC_DEFINE
57 Literal arguments to these are passed to m4_pattern_allow now.
60 Passing 'ac_cv_prog_cc_stdc=no' to 'configure' now sets ac_cv_prog_cc_c99
61 and ac_cv_prog_cc_c89 to 'no' as well, for backward compatibility with
62 obsolete K&R tests in the Automake test suite.
71 Now more robust with special characters in file names, or when
72 multiple processes create the same directory at the same time.
75 The documentation now says that the following macros are obsolescent:
76 they test for problems that are so old that they are no longer of
77 practical importance on current systems.
79 AC_C_BACKSLASH_A AC_FUNC_MEMCMP AC_HEADER_DIRENT
80 AC_C_CONST AC_FUNC_SELECT_ARGTYPES AC_HEADER_STAT
81 AC_C_PROTOTYPES AC_FUNC_SETPGRP AC_HEADER_STDC
82 AC_C_STRINGIZE AC_FUNC_SETVBUF_REVERSED AC_HEADER_SYS_WAIT
83 AC_C_VOLATILE AC_FUNC_STAT AC_HEADER_TIME
84 AC_FUNC_CLOSEDIR_VOID AC_FUNC_STRFTIME AC_ISC_POSIX
85 AC_FUNC_GETPGRP AC_FUNC_UTIME_NULL AC_PROG_GCC_TRADITIONAL
86 AC_FUNC_LSTAT AC_FUNC_VPRINTF AC_STRUCT_TM
88 New programs need not use these macros. We have no current plans to
92 For compatibility with future Libtool 2.0, autoreconf will invoke
93 libtoolize with the option `--ltdl' now, if LT_CONFIG_LTDL_DIR is
96 * Major changes in Autoconf 2.59c
98 Released 2006-04-12, by Ralf Wildenhues.
100 ** The configure command now redirects standard input from /dev/null,
101 to help avoid problems with subsidiary commands that might mistakenly
102 read standard input. AS_ORIGINAL_STDIN_FD points to the original
103 standard input before this redirection, if you really want configure to
104 read from standard input.
106 ** Directory variables adjusted to recent changes in the GNU Coding Standards.
107 The following directory variables are new:
109 datarootdir read-only architecture-independent data root [PREFIX/share]
110 localedir locale-specific message catalogs [DATAROOTDIR/locale]
111 docdir documentation root [DATAROOTDIR/doc/PACKAGE]
112 htmldir html documentation [DOCDIR]
113 dvidir dvi documentation [DOCDIR]
114 pdfdir pdf documentation [DOCDIR]
115 psdir ps documentation [DOCDIR]
117 The following variables have new default values:
119 datadir read-only architecture-independent data [DATAROOTDIR]
120 infodir info documentation [DATAROOTDIR/info]
121 mandir man documentation [DATAROOTDIR/man]
123 This means that if you use any of `@datadir@', `@infodir@', or
124 `@mandir@' in a file, you will have to ensure `${datarootdir}' is
125 defined in this file. As a temporary measure, if any of those are
126 found but no mention of `datarootdir', the substitutions will be
127 replaced with values that do not contain `${datarootdir}', and a
128 warning will be issued.
130 ** @top_builddir@ is now a dir name: it is always nonempty and doesn't have
131 a trailing slash. Similar change will be made to ac_top_builddir in a
132 future release; the old style value, which matches (../)*, is (and will
133 continue to be) available as ac_top_build_prefix.
136 New macro to check for support of 'typeof' syntax a la GNU C.
138 ** AC_CHECK_DECLS_ONCE, AC_CHECK_FUNCS_ONCE, AC_CHECK_HEADERS_ONCE
139 New "once-only" variants of commonly-used macros, to make 'configure'
140 smaller and faster in common cases.
143 New macro to check for strtold with C99 semantics.
146 New macro that lets builder disable assertions at 'configure'-time.
149 Now checks for X11/Xlib.h and XrmInitialize (X proper) rather than
150 X11/Intrinsic.h and XtMalloc (Xt).
152 ** AC_PRESERVE_HELP_ORDER
153 New macro that causes `configure' to display help strings for AC_ARG_ENABLE
154 and AC_ARG_WITH arguments in one region, in the order defined. The default
155 behavior is to group options of each classes separately.
157 ** AC_PROG_CC, AC_PROG_CXX
158 No longer automatically arrange to declare the 'exit' function of C,
159 when a C++ compiler is used. Standard Autoconf macros no longer use
160 'exit', so this is no longer an issue for them. If you use C++, and
161 want to call 'exit', you'll have to arrange for its declaration
162 yourself. But we now suggest you return from 'main' instead.
164 ** AC_PROG_CC_C89, AC_PROG_CC_C99
165 New macros for ISO C99 support. AC_PROG_CC_C89 and AC_PROG_CC_C99
166 check for ANSI C89 and ISO C99 support respectively.
169 Has been unobsoleted, and will check if the compiler supports ISO
170 C99, falling back to ANSI C89 if not. ac_cv_prog_cc_stdc is
171 retained for backwards compatibility, assuming the value of
172 ac_cv_prog_cc_c99 or ac_cv_prog_cc_c89 (whichever is valid, in
175 ** AC_STRUCT_DIRENT_D_INO, AC_STRUCT_DIRENT_D_TYPE
176 New macros for checking commonly-used members of struct dirent.
179 The substituted value can now contain newlines.
182 The substitution now occurs only when @variable@ is on a line by itself,
183 optionally surrounded by spaces and tabs. The whole line is replaced.
185 ** AC_TYPE_LONG_DOUBLE, AC_TYPE_LONG_DOUBLE_WIDER
186 New macros to check for long double, and whether it is wider than double.
187 The old macro AC_C_TYPE_LONG_DOUBLE has been marked as obsolete;
188 applications should switch to the new macro.
190 ** AC_TYPE_INT8_T, AC_TYPE_INT16_T, AC_TYPE_INT32_T, AC_TYPE_INT64_T,
191 AC_TYPE_INTMAX_T, AC_TYPE_INTPTR_T, AC_TYPE_LONG_LONG_INT, AC_TYPE_SSIZE_T,
192 AC_TYPE_UINT8_T, AC_TYPE_UINT16_T, AC_TYPE_UINT32_T, AC_TYPE_UINT64_T,
193 AC_TYPE_UINTMAX_T, AC_TYPE_UINTPTR_T, AC_TYPE_UNSIGNED_LONG_LONG_INT
194 New macros to check for C99 and POSIX types.
196 ** AC_USE_SYSTEM_EXTENSIONS
197 New macro to enable extensions to Posix.
200 New macro which is defined to the name of the first declared config header
201 or undefined if no config headers have been declared yet.
204 The macro correctly handles quadrigraphs now.
206 ** AS_BOURNE_COMPATIBLE, AS_SHELL_SANITIZE, AS_CASE
207 These macros are new or published now.
210 New macro for copyright notices in testsuite files.
212 ** ALLOCA, LIBOBJS, LTLIBOBJS
213 Object names added to these variables are now prefixed with `${LIBOBJDIR}',
214 as in `${LIBOBJDIR}alloca.o'. LIBOBJDIR is meant to be defined from
215 `Makefile.in' in case the object files lie in a different directory.
216 The LIBOBJDIR feature is experimental.
219 Supports --no-recursive now.
221 ** New macros to support Erlang/OTP.
222 New macros for configuring paths to Erlang tools and libraries:
223 AC_ERLANG_PATH_ERLC, AC_ERLANG_NEED_ERLC, AC_ERLANG_PATH_ERL,
224 AC_ERLANG_NEED_ERL, AC_ERLANG_CHECK_LIB, AC_ERLANG_SUBST_ROOT_DIR,
225 AC_ERLANG_SUBST_LIB_DIR.
227 New macros for configuring installation of Erlang libraries:
228 AC_ERLANG_SUBST_INSTALL_LIB_DIR, AC_ERLANG_SUBST_INSTALL_LIB_SUBDIR.
230 ** The manual now mentions Gnulib more prominently.
232 ** New macros to support Objective C.
233 AC_PROG_OBJC, AC_PROG_OBJCPP.
235 * Major changes in Autoconf 2.59b
237 Released 2004-08-20, by Paul Eggert.
240 New macro that computes the default alignment of a type.
242 ** AC_CHECK_TOOL, AC_PATH_TOOL, AC_CHECK_TOOLS
243 When cross-compiling, these macros will give a warning if the tool
244 is not prefixed. In the future, unprefixed cross tools will not
245 be detected; please consult the info documentation for information
246 about the reason of this change.
248 ** AC_CHECK_TARGET_TOOL, AC_PATH_TARGET_TOOL, AC_CHECK_TARGET_TOOLS
249 New macros that detect programs whose name is prefixed with the
250 target type, if the build type and target type are different.
252 ** AC_REQUIRE_AUX_FILE
253 New trace macro that declares expected auxiliary files.
256 New macro that tests for a grep program that accepts as a long a line
259 ** AC_PROG_EGREP, AC_PROG_FGREP
260 These macros now require AC_PROG_GREP, and try EGREP="$GREP -E" and
261 FGREP="$GREP -F" respectively if possible, or else run a path search for
262 a program that accepts as long a line as possible.
265 New macro that tests for a sed program that truncates as few characters
268 * Major changes in Autoconf 2.59
270 Released 2003-11-04, by Akim Demaille
272 ** ac_abs_builddir etc.
273 Absolute file names were actually relative in 2.58.
275 * Major changes in Autoconf 2.58
277 Released 2003-11-04, by Akim Demaille
280 core.* files are no longer removed, as they may be valid user files.
282 ** autoreconf and auxiliary directory
283 Autoreconf creates the auxiliary directory if needed. This is
284 especially useful for initial "bootstrapping" of fresh CVS checkouts.
286 ** AC_CONFIG_MACRO_DIR
287 Use this macro to declare the directory for local M4 macros for aclocal.
290 No longer includes twice the same file in LIBOBJS if invoked
293 ** AC_CONFIG_COMMANDS
294 The directory for its first argument is automatically created. For
297 AC_CONFIG_COMMANDS([src/modules.hh], [...])
299 $top_builddir/src/ is created if needed.
301 ** Autotest and local.at
302 The optional file local.at is always included in Autotest test suites.
305 The warnings are always issued, including with cached runs.
306 This became a significant problem since aclocal and automake can
307 run autoconf behind the scene.
309 ** autoheader warnings
310 The warnings of autoheader can be turned off, using --warning.
311 For instance, -Wno-obsolete disables the complaints about acconfig.h
312 and other deprecated constructs.
315 AC_C_RESTRICT, AC_INCLUDES_DEFAULT, AC_LANG_ASSERT, AC_LANG_WERROR,
318 ** AC_DECL_SYS_SIGLIST
322 Now checks that mktime is the inverse of localtime.
324 ** Improve DJGPP portability
325 The Autoconf tools and configure behave better under DJGPP.
327 ** Present But Cannot Be Compiled
328 New FAQ section dedicated to the mystic
330 configure: WARNING: pi.h: present but cannot be compiled
331 configure: WARNING: pi.h: check for missing prerequisite headers?
332 configure: WARNING: pi.h: proceeding with the preprocessor's result
335 ** Concurrent executions of autom4te
336 autom4te now locks its internal files, which enables concurrent
337 executions of autom4te, likely to happen if automake, autoconf,
338 autoheader etc. are run simultaneously.
341 Use of Libtool 1.5 and higher is encouraged. Compatibility with
342 Libtool pre-1.4 is not checked.
345 Testsuites no longer rerun failed tests in verbose mode; instead,
346 failures are logged while the test is run.
348 In addition, expected failures can be marked as such.
350 * Major changes in Autoconf 2.57
352 Released 2002-12-03 by Paul Eggert.
354 Bug fixes for problems with AIX linker, with freestanding C compilers,
355 with GNU M4 limitations, and with obsolete copies of GNU documents.
357 The Free Documentation License has been upgraded from 1.1 to 1.2.
359 * Major changes in Autoconf 2.56
361 Released 2002-11-15 by Akim Demaille.
363 One packaging problem fixed (config/install-sh was not executable).
365 * Major changes in Autoconf 2.55
367 Released 2002-11-14 by Akim Demaille.
371 Have your configure.ac checked by autoscan ("autoscan").
372 Try the warning options ("autoreconf -fv -Wall").
376 - AC_CHECK_HEADER, AC_CHECK_HEADERS
377 More information on proper use.
379 - Writing Test Programs
381 This sections explains how to write good test sources to use with
382 AC_COMPILE_IFELSE etc. It documents AC_LANG_PROGRAM and so forth.
384 - AC_FOO_IFELSE vs. AC_TRY_FOO
386 Explains why Autoconf moves from AC_TRY_COMPILE etc. to
387 AC_COMPILE_IFELSE and AC_LANG_PROGRAM etc.
391 - Is more robust to different Gettext installations.
393 - Produces messages (when --verbose) to be understood by Emacs'
396 - Supports -W/--warnings.
399 Once the GNU Build System reinstalled, run `./config.status
400 --recheck && ./config.status && make' if possible.
404 - Supports --cache, and --no-cache.
406 - ~/.autom4te.cfg makes it possible to disable the caching mechanism
407 (autom4te.cache). See `Customizing autom4te' in the documentation.
414 Support for the obsoleted options -m, --macrodir, -l, --localdir is
415 dropped in favor of the safer --include/--prepend-include scheme.
420 AC_COMPILER_IFELSE, AC_FUNC_MBRTOWC, AC_HEADER_STDBOOL,
421 AC_LANG_CONFTEST, AC_LANG_SOURCE, AC_LANG_PROGRAM, AC_LANG_CALL,
422 AC_LANG_FUNC_TRY_LINK, AC_MSG_FAILURE, AC_PREPROC_IFELSE.
425 Obsoleted macros are kept for Autoconf backward compatibility, but
426 should be avoided in configure.ac. Running autoupdate is advised.
429 - AC_DEFINE/AC_DEFINE_UNQUOTED
431 We have to stop using the old compatibility scheme --that tried to
432 avoid useless backslashes-- because Libtool 1.4.3 contains a
434 AC_DEFINE([error_t], [int],
435 [Define to a type to use for \`error_t' if it is not
436 otherwise available.])
438 We have to quote the single quotes and backslashes with \. The old
439 compatibility scheme saw that ` was backslashed, and therefore did
440 not quote the single quote... Failure. Hence, Autoconf 2.54 is not
441 compatible with Libtool. Autoconf 2.55 is, but in some cases might
442 produce more \ than wanted.
444 Please, note that in the future the same problem will happen with
445 AC_MSG_*: use `autoreconf -f -Wall'.
449 - Portability of the Autoconf package to Solaris.
451 - Spurious warnings caused by config.status.
452 This bug is benign, but painful: on some systems (typically
453 FreeBSD), warnings such as:
455 config.status: creating Makefile
456 mv: Makefile: set owner/group (was: 1357/0): Operation not permitted
458 could be issued. This is fixed.
461 Simultaneous executions of config.status are possible again.
463 - Precious variables accumulation
465 config.status could stack several copies of the precious variables
469 ** Plans for later versions
473 The compatibility hooks with the old scheme will be completely
474 removed. Please, advice/use `--build', `--host', and `--target'
477 - AC_CHECK_HEADER, AC_CHECK_HEADERS
479 The tests will be stricter, please make sure your invocations are
484 Shell functions will gradually be introduced, probably starting with
485 Autotest. If you know machines which are in use that you suspect
486 *not* to support shell functions, please run the test suite of
487 Autoconf 2.55 on it, and report the results to
488 bug-autoconf@gnu.org.
492 Special characters in AC_MSG_* need not be quoted. Currently,
493 Autoconf has heuristics to decide when a string is escaped, or has
494 to be escaped. This scheme is fragile, and will be removed; the
495 only risk is uglified messages. Please, run `autoreconf -f -Wall'
496 to find occurrences that will be affected.
498 * Major changes in Autoconf 2.54
500 Released 2002-09-13 by Akim Demaille.
504 - autoreconf no longer changes the version of the gettext/po/intl
505 support files. It now adds the files the correspond to the
506 AM_GNU_GETTEXT_VERSION declared in configure.ac.
508 Warning: It now relies on the 'autopoint' program, which is part
509 of GNU gettext 0.11.4 and newer.
511 Please note that you need to have a GNU gettext version that
512 corresponds at least to the AM_GNU_GETTEXT_VERSION declared
513 in configure.ac. You can upgrade to newer GNU gettext versions,
514 though, without needing to change configure.ac.
516 - The -I DIR or --include=DIR option now appends DIR to the include path
517 instead of prepending; this is for consistency with other GNU tools.
518 The new -B DIR or --prepend-include=DIR option has the old behavior.
523 Now handles all the gory details about LIBOBJS and LTLIBOBJS.
524 Please, remove lines such as
526 # This is necessary so that .o files in LIBOBJS are also
527 # built via the ANSI2KNR-filtering rules.
528 LIBOBJS=`echo $LIBOBJS|sed 's/\.o /\$U.o /g;s/\.o$/\$U.o/'`
530 and read the `AC_LIBOBJ vs LIBOBJS' section. Do not define U in
531 your Makefiles either.
533 - AC_CONFIG_LINKS now makes copies if it can't make links.
535 - AC_FUNC_FNMATCH now tests only for POSIX compatibility, reverting to
536 Autoconf 2.13 behavior. The new macro AC_FUNC_FNMATCH_GNU also
537 tests for GNU extensions to fnmatch, and replaces fnmatch if needed.
539 - AC_FUNC_SETVBUF_REVERSED no longer fails when cross-compiling.
541 - AC_PROG_CC_STDC is integrated into AC_PROG_CC.
543 - AC_PROG_F77 default search no longer includes cf77 and cfg77.
547 AC_C_BACKSLASH_A, AC_CONFIG_LIBOBJ_DIR, AC_GNU_SOURCE,
548 AC_PROG_EGREP, AC_PROG_FGREP, AC_REPLACE_FNMATCH,
549 AC_FUNC_FNMATCH_GNU, AC_FUNC_REALLOC, AC_TYPE_MBSTATE_T.
552 looks for getloadavg.c in the CONFIG_LIBOBJ_DIR.
555 Now defines HAVE_MALLOC to 0 if `malloc' does not work, and asks
556 for an AC_LIBOBJ replacement.
560 - Spurious complaints from `m4_bmatch' about invalid regular
561 expressions are suppressed.
563 - Empty top_builddirs are properly handled.
565 - AC_CHECK_MEMBER works correctly when the member is an aggregate.
568 Now colon in the optional path arguments are properly handled.
570 ** Improved portability
572 - Both Autoconf the package, and the scripts it produces, should run
573 more reliably with Zsh. Bear in mind it is the default Bourne shell
576 - Autoconf and the scripts it produces no longer assume the existence of
577 the obsolescent commands egrep and fgrep.
581 - Limitations of Make
585 The GNATS base moved to
586 http://bugs.gnu.org/cgi-bin/gnatsweb.pl?database=autoconf
587 (It is no longer available, though.)
592 Now contains the list of ouput variables and files (AC_SUBST,
595 * Major changes in Autoconf 2.53
597 Released 2002-03-08 by Akim Demaille.
601 Perl 5.005_03 or later is required: autom4te is written in Perl and is
602 needed by autoconf. autoheader, autoreconf, ifnames, and autoscan are
608 Argument requirements, output variables, defined macros.
609 - M4sugar, M4sh, Autotest
611 - Double quoting macros
612 AC_TRY_CPP, AC_TRY_COMPILE, AC_TRY_LINK and AC_TRY_RUN.
614 The Autoconf manual is now distributed under the terms of the GNU FDL.
615 - Section `Hosts and Cross-Compilation'
616 Explains the rationale for the 2.5x changes in the cross-compilation
617 chain, and in the relationships between build, host, and target
619 Emphasizes that `cross-compilation' == `--host is given'.
620 If you are working on compilers etc., be sure to read this section.
621 - Section `AC_LIBOBJ vs. LIBOBJS'
622 Explains why assigning LIBOBJS directly is now an error.
623 Details how to update the code.
628 Now used instead of hard coded line numbers.
629 This eases the comparison of `configure's, and diminishes the
630 pressure over control version archives.
631 Automatic replacement for shells that don't support this feature.
632 - New output variables
633 @builddir@, @top_builddir@, @abs_srcdir@, @abs_top_srcdir@, @abs_builddir@,
638 Autoconf and Autotest modes are provided.
643 New, used by the Autoconf suite to cache and speed up most processing.
645 Supported by autom4te, autoconf and autoheader.
647 Replaces --autoconf-dir and --localdir in autoconf, autoheader,
648 autoupdate, and autoreconf.
650 No longer passes --cygnus, --foreign, --gnits, --gnu, --include-deps:
651 automake options are to be given via AUTOMAKE_OPTIONS.
653 Runs gettextize and libtoolize when appropriate.
655 --m4dir is no longer supported.
657 Now runs only in the specified directories, defaulting to `.',
658 but understands AC_CONFIG_SUBDIRS for dependent directories.
659 Before, it used to run on all the `configure.ac' found in the
661 Independent packages are properly updated.
665 - The top level $prefix is propagated to the AC_CONFIG_SUBDIRS configures.
667 Under the user pressure, $? is finally available. Probably a mistake.
668 - AC_F77_LIBRARY_LDFLAGS now supports the HP/UX f90 compiler.
669 - Precious variables accumulation
670 config.status could stack several copies of the precious variables
672 - AC_PATH_PROG and family.
673 Works properly when given a literal path.
675 Somewhere since 2.13, the result had been reversed.
679 - AC_C_BIGENDIAN supports the cross-compiling case.
680 - AC_C_BIGENDIAN accepts ACTION-IF-TRUE, ACTION-IF-FALSE, and
681 ACTION-IF-UNKNOWN arguments. All are facultative, and the default
682 for ACTION-IF-TRUE is to define WORDS_BIGENDIAN like AC_C_BIGENDIAN
684 - AC_C_LONG_DOUBLE now succeeds only if `long double' has more range or
685 precision than `double'.
690 It now defines the preprocessor symbols PACKAGE_NAME,
691 PACKAGE_TARNAME, PACKAGE_VERSION, PACKAGE_STRING, and
695 Admits a fourth optional parameter: the tar name.
697 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS.
698 Provide the user with srcdir, ac_srcdir, ac_top_srcdir, ac_builddir,
699 ac_top_builddir, ac_abs_srcdir, ac_abs_top_srcdir, ac_abs_builddir,
702 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS and AC_OUTPUT.
703 Are much less expensive when using long lists of files.
706 Works with shell variables, and non alphanumeric names.
710 - AC_FUNC_STRERROR_R now sets STRERROR_R_CHAR_P, not HAVE_WORKING_STRERROR_R,
711 because POSIX 1003.1-200x draft 7 says strerror_r returns int, not char *.
713 - AC_FUNC_STRTOD substitutes POW_LIB.
718 * Major changes in Autoconf 2.52
720 Released 2001-07-18 by Akim Demaille.
725 This feature was present in autoconf 2.50 but was not documented.
726 For example, `@<:@' is translated to `[' just before output. This
727 is useful when writing strings that contain unbalanced quotes, or
728 other hard-to-quote constructs.
729 - m4_pattern_forbid, m4_pattern_allow
730 - Tips for upgrading from 2.13.
731 - Using autoscan to maintain a configure.ac.
734 - Now include stdint.h.
735 - sys/types.h and sys/stat.h are guarded.
736 - strings.h is included if available, and not conflicting with string.h.
739 - The test suite is more robust and presents less false failures.
740 - Invocation of GNU M4 now robust to POSIXLY_CORRECT.
741 - configure accepts --prefix='' again.
742 - AC_CHECK_LIB works properly when its first argument is not a
744 - HAVE_INTTYPES_H is defined only if not conflicting with sys/types.h.
745 - build_, host_, and target_alias are AC_SUBST as in 2.13.
746 - AC_ARG_VAR properly propagates precious variables inherited from the
747 environment to ./config.status.
748 - Using --program-suffix/--program-prefix is portable.
749 - Failures to detect the default compiler's output extension are less
751 - `config.status foo' works properly when `foo' depends on variables
752 set in an AC_CONFIG_THING INIT-CMD.
753 - autoheader is more robust to broken input.
754 - Fixed Fortran name-mangling and link tests on a number of systems,
755 e.g. NetBSD; see AC_F77_DUMMY_MAIN, below.
758 - AC_CHECK_HEADER and AC_CHECK_HEADERS support a fourth argument to
759 specify pre-includes. In this case, the headers are compiled with
760 cc, not merely preprocessed by cpp. Therefore it is the _usability_
761 of a header which is checked for, not just its availability.
762 - AC_ARG_VAR refuses to run configure when precious variables have
764 - Versions of compilers are dumped in the logs.
765 - AC_CHECK_TYPE recognizes use of `foo_t' as a replacement type.
768 - AC_PATH_XTRA only adds -ldnet to $LIBS if it's needed to link.
769 - AC_FUNC_WAIT3 and AC_SYS_RESTARTABLE_SYSCALLS are obsoleted.
770 - AM_FUNC_ERROR_AT_LINE, AM_FUNC_FNMATCH, AM_FUNC_MKTIME,
771 AM_FUNC_OBSTACK, and AM_FUNC_STRTOD are now activated.
772 Be sure to read `Upgrading from Version 2.13' to understand why
773 running `autoupdate' is needed.
774 - AC_F77_DUMMY_MAIN, AC_F77_MAIN: new macros to detect whether
775 a main-like routine is required/possible when linking C/C++ with
776 Fortran. Users of e.g. AC_F77_WRAPPERS should be aware of these.
777 - AC_FUNC_GETPGRG behaves better when cross-compiling.
779 * Major changes in Autoconf 2.51
780 There was no release of Autoconf 2.51 since some packagers had used
781 this version number without permission to ship intermediary versions
782 of 2.50. The version was skipped to avoid confusion.
784 * Major changes in Autoconf 2.50
786 Released 2001-05-21 by Akim Demaille.
789 There have been far too many to enumerate them here. Check out
790 ChangeLog if you really want to know more.
792 ** Improved documentation
793 In particular, portability issues are better covered.
796 All the standard GNU Makefile targets are supported. The layout has
797 changed: m4/ holds the M4 extensions Autoconf needs for its
798 configuration, doc/ contains the documentation, and tests/ contains
801 ** Man pages are provided
802 For autoconf, autoreconf, autoupdate, autoheader, autoscan, ifnames,
803 config.guess, config.sub.
807 Provides a safe and powerful means to trace the macro uses. This
808 provide the parsing layer for tools which need to `study'
812 Specify what category of warnings should be enabled.
814 - When recursing into subdirectories, try for configure.gnu before
815 configure to adapt for packages not using autoconf on case-insensitive
819 More errors are now caught (circular AC_REQUIRE dependencies,
820 AC_DEFINE in the action part of an AC_CACHE_CHECK, too many pops
821 etc.). In addition, their location and call stack are given.
824 autoupdate is much more powerful, and is able to provide the glue code
825 which might be needed to move from an old macro to its newer
828 You are strongly encouraged to use it to modernize both your
829 `configure.in' and your .m4 extension files.
832 The internal machinery of autoheader has completely changed. As a
833 result, using `acconfig.h' should be considered to be obsoleted, and
834 you are encouraged to get rid of it using the AH macros.
839 ** Fortran 77 compilers
840 Globally, the support for Fortran 77 is considerably improved.
842 Support for automatically determining a Fortran 77 compiler's
843 name-mangling scheme. New CPP macros F77_FUNC and F77_FUNC_ are
844 provided to wrap C/C++ identifiers, thus making it easier and more
845 transparent for C/C++ to call Fortran 77 routines, and Fortran 77 to
846 call C/C++ routines. See the Texinfo documentation for details.
849 The test suite no longer uses DejaGNU. It should be easy to submit
850 test cases in this new framework.
853 - --help, --help=long, -hl
854 no longer dumps useless items.
856 lists only specific options.
857 - --help=recursive, -hr
858 displays the help of all the embedded packages.
859 - Remembers environment variables when reconfiguring.
860 The previous scheme to set envvar before running configure was
862 what prevented configure from remembering the environment in which
863 it was run, therefore --recheck was run in an inconsistent
864 environment. Now, one should run
866 and then --recheck will work properly. Variables declared with
867 AC_ARG_VAR are also preserved.
869 $build defaults to `config.guess`, $host to $build, and then $target
871 Cross-compilation is a global status of the package, it no longer
872 depends upon the current language.
873 Cross compilation is enabled iff the user specified `--host'.
874 `configure' now fails if it can't run the executables it compiles,
875 unless cross-compilation is enabled.
877 The cache file is disabled by default. The new options
878 `--config-cache', `-C' set the cache to `config.cache'.
882 Much faster on most architectures.
883 - concurrent executions
884 It is safe to use `make -j' with config.status.
885 - human interface improved
886 It is possible to invoke
887 ./config.status foobar
888 instead of the former form (still valid)
889 CONFIG_COMMANDS= CONFIG_HEADERS= CONFIG_LINKS= \
890 CONFIG_FILES=foobar:foo.in:bar.in \
892 The same holds for configuration headers and links.
893 You can instantiate unknown files and headers:
894 ./config.status --header foo.h:foo.h.in --file bar:baz
895 - has a useful --help
896 - accepts special file name "-" for stdin/stdout
901 Specify additional copyright information.
904 Now expects the identity of the package as argument.
908 Most macros, if not all, now strictly follow the `one quotation
909 level' rule. This results in a more predictable expansion.
912 A sly bug in the AC_REQUIRE machinery, which could produce incorrect
913 configure scripts, was fixed by Axel Thimm.
917 Document and ask for the registration of an envvar.
920 Specifies the file which `configure' should look for when trying to
921 find the source tree (used to be handled by AC_INIT).
924 To add new actions to config.status. Should be used instead of
928 Replaces AC_LINK_FILES.
930 - AC_CONFIG_HEADERS, AC_CONFIG_COMMANDS, AC_CONFIG_SUBDIRS,
931 AC_CONFIG_LINKS, and AC_CONFIG_FILES
932 They now obey sh: you should no longer use shell variables as
935 test "$package_foo_enabled" = yes && $my_subdirs="$my_subdirs foo"
936 AC_CONFIG_SUBDIRS($my_subdirs)
940 if test "$package_foo_enabled" = yes; then
941 AC_CONFIG_SUBDIRS(foo)
945 To format an Autoconf macro's help string so that it looks pretty
946 when the user executes `configure --help'.
949 ** Generic Test Macros
951 The interface of the AC_CHECK families of macros (decl, header,
952 type, member, func) is now uniform. They support the same set of
955 - AC_CHECK_DECL, AC_CHECK_DECLS
956 To check whether a symbol is declared.
958 - AC_CHECK_SIZEOF, AC_C_CHAR_UNSIGNED.
959 No longer need a cross-compilation default.
962 The test it performs is much more robust than previously, and makes
963 it possible to test builtin types in addition to typedefs.
964 It is now schizophrenic:
965 - AC_CHECK_TYPE(TYPE, REPLACEMENT)
966 remains for backward compatibility, but its use is discouraged.
967 - AC_CHECK_TYPE(TYPE, IF-FOUND, IF-NOT-FOUND, INCLUDES)
968 behaves exactly like the other AC_CHECK macros.
971 Checks whether given types are supported by the system.
973 - AC_CHECK_MEMBER, AC_CHECK_MEMBERS
974 Check for given members in aggregates (e.g., pw_gecos in struct
978 Checks if the compiler supports ISO C, included when needs special
982 Checking whether the preprocessor indicates missing includes by the
983 error code. stderr is checked by AC_TRY_CPP only as a fallback.
986 Takes a language as argument and replaces AC_LANG_C,
987 AC_LANG_CPLUSPLUS and AC_LANG_FORTRAN77.
989 - AC_LANG_PUSH, AC_LANG_POP
990 Are preferred to AC_LANG_SAVE, AC_LANG_RESTORE.
993 - AC_FUNC_CHOWN, AC_FUNC_MALLOC, AC_FUNC_STRERROR_R,
994 AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK, AC_FUNC_STAT, AC_FUNC_LSTAT,
995 AC_FUNC_ERROR_AT_LINE, AC_FUNC_OBSTACK, AC_FUNC_STRTOD, AC_FUNC_FSEEKO.
1001 - AC_FUNC_GETLOADAVG
1002 Defines `HAVE_STRUCT_NLIST_N_UN_N_NAME' instead of `NLIST_NAME_UNION'.
1005 Now integrates `AC_DECL_YYTEXT' which is obsoleted.
1008 Arrange for large-file support.
1010 - AC_EXEEXT, AC_OBJEXT
1011 You are no longer expected to use them: their computation is
1012 performed by default.
1014 ** C++ compatibility
1015 Every macro has been revisited in order to support at best CC=c++.
1017 Major changes in Autoconf 2.14:
1018 There was no release of GNU Autoconf 2.14.
1020 Major changes in Autoconf 2.13:
1022 Released 1999-05-01 by Ben Elliston.
1024 * Support for building on Win32 systems where the only available C or
1025 C++ compiler is the Microsoft Visual C++ command line compiler
1026 (`cl'). Additional support for building on Win32 systems which are
1027 using the Cygwin or Mingw32 environments.
1028 * Support for alternative object file and executable file extensions.
1029 On Win32, for example, these are .obj and .exe. These are discovered
1030 using AC_OBJEXT and AC_EXEEXT, which substitute @OBJEXT@ and
1031 @EXEEXT@ in the output, respectively.
1032 * New macros: AC_CACHE_LOAD, AC_CACHE_SAVE, AC_FUNC_SELECT_ARGTYPES,
1033 AC_VALIDATE_CACHED_SYSTEM_TUPLE, AC_SEARCH_LIBS, AC_TRY_LINK_FUNC,
1034 AC_C_STRINGIZE, AC_CHECK_FILE(S), AC_PROG_F77 (and friends).
1035 * AC_DEFINE now has an optional third argument for a description to be
1036 placed in the config header input file (e.g. config.h.in).
1037 * The C++ code fragment compiled for the C++ compiler test had to be
1038 improved to include an explicit return type for main(). This was
1039 causing failures on systems using recent versions of the EGCS C++
1041 * Fixed an important bug in AC_CHECK_TYPE that would cause a configure
1042 script to report that `sometype_t' was present when only `type_t'
1044 * Merge of the FSF version of config.guess and config.sub to modernize
1045 these scripts. Add support for a few new hosts in config.guess.
1046 Incorporate latest versions of install-sh, mkinstalldirs and
1047 texinfo.tex from the FSF.
1048 * autoreconf is capable of running automake if necessary (and
1050 * Support for Fortran 77. See the Texinfo documentation for details.
1051 * Bug fixes and workarounds for quirky bugs in vendor utilities.
1053 Major changes in Autoconf 2.12:
1055 Released 1996-11-26 by David J. MacKenzie
1057 * AC_OUTPUT and AC_CONFIG_HEADER can create output files by
1058 concatenating multiple input files separated by colons, like so:
1059 AC_CONFIG_HEADER(config.h:conf.pre:config.h.in:conf.post)
1060 AC_OUTPUT(Makefile:Makefile.in:Makefile.rules)
1061 The arguments may be shell variables, to compute the lists on the fly.
1062 * AC_LINK_FILES and AC_CONFIG_SUBDIRS may be called multiple times.
1063 * New macro AC_OUTPUT_COMMANDS adds more commands to run in config.status.
1066 Major changes in Autoconf 2.11:
1068 Released November 18th, 1996, by David J. MacKenzie
1070 * AC_PROG_CC and AC_PROG_CXX check whether the compiler works.
1071 They also default CFLAGS/CXXFLAGS to "-g -O2" for gcc, instead of "-g -O".
1072 * AC_REPLACE_FUNCS defines HAVE_foo if the system has the function `foo'.
1073 * AC_CONFIG_HEADER expands shell variables in its argument.
1074 * New macros: AC_FUNC_FNMATCH, AC_FUNC_SETPGRP.
1075 * The "checking..." messages and the source code for test programs that
1076 fail are saved in config.log.
1077 * Another workaround has been added for seds with small command length limits.
1078 * config.sub and config.guess recognize more system types.
1081 Major changes in Autoconf 2.10:
1083 Released May 7th, 1996, by Roland McGrath
1086 * The cache variable names used by `AC_CHECK_LIB(LIB, FUNC, ...)' has
1087 changed: now $ac_cv_lib_LIB_FUNC, previously $ac_cv_lib_LIB.
1089 Major changes in Autoconf 2.9:
1091 Released March 16th, 1996, by Roland McGrath
1095 Major changes in Autoconf 2.8:
1097 Released March 8th, 1996, by Roland McGrath
1101 Major changes in Autoconf 2.7:
1103 Released November 22nd, 1995, by David J. MacKenzie
1107 Major changes in Autoconf 2.6:
1109 Released November 20th, 1995, by David J. MacKenzie
1113 Major changes in Autoconf 2.5:
1115 Released November 17th, 1995, by Roland McGrath
1117 * New configure options --bindir, --libdir, --datadir, etc., with
1118 corresponding output variables.
1119 * New macro: AC_CACHE_CHECK, to make using the cache easier.
1120 * config.log contains the command being run as well as any output from it.
1121 * AC_CHECK_LIB can check for libraries with "." or "/" or "+" in their name.
1122 * AC_PROG_INSTALL doesn't cache a name for install-sh, for sharing caches.
1123 * AC_CHECK_PROG, AC_PATH_PROG, AC_CHECK_PROGS, AC_PATH_PROGS, and
1124 AC_CHECK_TOOL can search a path other than $PATH.
1125 * AC_CHECK_SIZEOF takes an optional size to use when cross-compiling.
1127 Major changes in Autoconf 2.4:
1129 Released June 14th, 1995, by David J. MacKenzie
1131 * Fix a few bugs found by Emacs testers.
1133 Major changes in Autoconf 2.3:
1135 Released March 27th, 1995, by David J. MacKenzie
1137 * Fix the cleanup trap in several ways.
1138 * Handle C compilers that are picky about option placement.
1139 * ifnames gets the version number from the right directory.
1141 Major changes in Autoconf 2.2:
1143 Released March 8th, 1995, by David J. MacKenzie
1145 * The ifnames utility is much faster but requires a "new awk" interpreter.
1146 * AC_CHECK_LIB and AC_HAVE_LIBRARY check and add the new
1147 library before existing libs, not after, in case it uses them.
1148 * New macros: AC_FUNC_GETPGRP, AC_CHECK_TOOL.
1149 * Lots of bug fixes.
1150 * Many additions to the TODO file :-)
1152 Major changes in Autoconf 2.1:
1154 Released November 4th, 1994, by David J. MacKenzie
1157 * More explanations in the manual.
1158 * Fix a spurious failure in the testsuite.
1159 * Clarify some warning messages.
1160 * autoreconf by default only rebuilds configure and config.h.in files
1161 that are older than any of their particular input files; there is a
1162 --force option to use after installing a new version of Autoconf.
1164 Thanks to everybody who's submitted changes and additions to Autoconf!
1165 I've incorporated many of them, and am still considering others for
1166 future releases -- but I didn't want to postpone this release indefinitely.
1168 Caution: don't indiscriminately rebuild configure scripts with
1169 Autoconf version 2. Some configure.in files need minor adjustments to
1170 work with it; the documentation has a chapter on upgrading. A few
1171 configure.in files, including those for GNU Emacs and the GNU C
1172 Library, need major changes because they relied on undocumented
1173 internals of version 1. Future releases of those packages will have
1174 updated configure.in files.
1176 It's best to use GNU M4 1.3 (or later) with Autoconf version 2.
1177 Autoconf now makes heavy use of M4 diversions, which were implemented
1178 inefficiently in GNU M4 releases before 1.3.
1180 Major changes in Autoconf 2.0:
1182 Released October 26th, 1994, by David J. MacKenzie
1184 ** New copyright terms:
1185 * There are no restrictions on distribution or use of configure scripts.
1188 * Autoconf manual is reorganized to make information easier to find
1189 and has several new indexes.
1190 * INSTALL is reorganized and clearer and is now made from Texinfo source.
1193 * autoscan to generate a preliminary configure.in for a package by
1194 scanning its source code for commonly used nonportable functions,
1195 programs, and header files.
1196 * ifnames to list the symbols used in #if and #ifdef directives in a
1198 * autoupdate to update a configure.in to use the version 2 macro names.
1199 * autoreconf to recursively remake configure and configuration header
1200 files in a source tree.
1202 ** Changed utilities:
1203 * autoheader can take pieces of acconfig.h to replace config.h.{top,bot}.
1204 * autoconf and autoheader can look for package-local definition files
1205 in an alternate directory.
1208 * AC_CACHE_VAL to share results of tests between configure runs.
1209 * AC_DEFUN to define macros, automatically AC_PROVIDE them, and ensure
1210 that macros invoked with AC_REQUIRE don't interrupt other macros.
1211 * AC_CONFIG_AUX_DIR, AC_CANONICAL_SYSTEM, AC_CANONICAL_HOST, AC_LINK_FILES to
1212 support deciding unguessable features based on the host and target types.
1213 * AC_CONFIG_SUBDIRS to recursively configure a source tree.
1214 * AC_ARG_PROGRAM to use the options --program-prefix,
1215 --program-suffix, and --program-transform-name to change the names
1216 of programs being installed.
1217 * AC_PREFIX_DEFAULT to change the default installation prefix.
1218 * AC_TRY_COMPILE to compile a test program without linking it.
1219 * AC_CHECK_TYPE to check whether sys/types.h or stdlib.h defines a given type.
1220 * AC_CHECK_LIB to check for a particular function and library.
1221 * AC_MSG_CHECKING and AC_MSG_RESULT to print test results, on a single line,
1222 whether or not the test succeeds. They obsolete AC_CHECKING and AC_VERBOSE.
1223 * AC_SUBST_FILE to insert one file into another.
1224 * AC_FUNC_MEMCMP to check whether memcmp is 8-bit clean.
1225 * AC_FUNC_STRFTIME to find strftime even if it's in -lintl.
1226 * AC_FUNC_GETMNTENT to find getmntent even if it's in -lsun or -lseq.
1227 * AC_HEADER_SYS_WAIT to check whether sys/wait.h is POSIX.1 compatible.
1230 * Many macros renamed systematically, but old names are accepted for
1231 backward compatibility.
1232 * AC_OUTPUT adds the "automatically generated" comment to
1233 non-Makefiles where it finds @configure_input@ in an input file, to
1234 support files with various comment syntaxes.
1235 * AC_OUTPUT does not replace "prefix" and "exec_prefix" in generated
1236 files when they are not enclosed in @ signs.
1237 * AC_OUTPUT allows the optional environment variable CONFIG_STATUS to
1238 override the file name "config.status".
1239 * AC_OUTPUT takes an optional argument for passing variables from
1240 configure to config.status.
1241 * AC_OUTPUT and AC_CONFIG_HEADER allow you to override the input-file names.
1242 * AC_OUTPUT automatically substitutes the values of CFLAGS, CXXFLAGS,
1243 CPPFLAGS, and LDFLAGS from the environment.
1244 * AC_PROG_CC and AC_PROG_CXX now set CFLAGS and CXXFLAGS, respectively.
1245 * AC_PROG_INSTALL looks for install-sh or install.sh in the directory
1246 specified by AC_CONFIG_AUXDIR, or srcdir or srcdir/.. or
1247 srcdir/../.. by default.
1248 * AC_DEFINE, AC_DEFINE_UNQUOTED, and AC_SUBST are more robust and smaller.
1249 * AC_DEFINE no longer prints anything, because of the new result reporting
1250 mechanism (AC_MSG_CHECKING and AC_MSG_RESULT).
1251 * AC_VERBOSE pays attention to --quiet/--silent, not --verbose.
1252 * AC_ARG_ENABLE and AC_ARG_WITH support whitespace in the arguments to
1253 --enable- and --with- options.
1254 * AC_CHECK_FUNCS and AC_CHECK_HEADERS take optional shell commands to
1255 execute on success or failure.
1256 * Checking for C functions in C++ works.
1259 * AC_REMOTE_TAPE and AC_RSH removed; too specific to tar and cpio, and
1260 better maintained with them.
1261 * AC_ARG_ARRAY removed because no one was likely using it.
1262 * AC_HAVE_POUNDBANG replaced with AC_SYS_INTERPRETER, which doesn't
1263 take arguments, for consistency with all of the other specific checks.
1266 * Comes with config.sub and config.guess, and uses them optionally.
1267 * Uses config.cache to cache test results. An alternate cache file
1268 can be selected with the --cache-file=FILE option.
1269 * Uses optional shell scripts $prefix/share/config.site and
1270 $prefix/etc/config.site to perform site or system specific initializations.
1271 * configure saves compiler output to ./config.log for debugging.
1272 * New files autoconf.m4 and autoheader.m4 load the other Autoconf macros.
1273 * acsite.m4 is the new name for the system-wide aclocal.m4.
1274 * Has a DejaGnu test suite.
1276 Major changes in Autoconf 1.11:
1278 * AC_PROG_INSTALL calls install.sh with the -c option.
1279 * AC_SET_MAKE cleans up after itself.
1280 * AC_OUTPUT sets prefix and exec_prefix if they weren't set already.
1281 * AC_OUTPUT prevents shells from looking in PATH for config.status.
1283 Plus a few other bug fixes.
1285 Major changes in Autoconf 1.10:
1287 * autoheader uses config.h.bot if present, analogous to config.h.top.
1288 * AC_PROG_INSTALL looks for install.sh in srcdir or srcdir/.. and
1290 * AC_PROG_CXX looks for cxx as a C++ compiler.
1292 Plus several bugs fixed.
1294 Major changes in Autoconf 1.9:
1296 * AC_YYTEXT_POINTER replaces AC_DECLARE_YYTEXT.
1297 * AC_SIZEOF_TYPE generates the cpp symbol name automatically,
1298 and autoheader generates entries for those names automatically.
1299 * AC_FIND_X gets the result from xmkmf correctly.
1300 * AC_FIND_X assumes no X if --without-x was given.
1301 * AC_FIND_XTRA adds libraries to the variable X_EXTRA_LIBS.
1302 * AC_PROG_INSTALL finds OSF/1 installbsd.
1304 Major changes in Autoconf 1.8:
1307 * New macros AC_LANG_C, AC_LANG_CPLUSPLUS, AC_LANG_SAVE, AC_LANG_RESTORE,
1308 AC_PROG_CXX, AC_PROG_CXXCPP, AC_REQUIRE_CPP
1309 for checking both C++ and C features in one configure script.
1310 * New macros AC_CHECKING, AC_VERBOSE, AC_WARN, AC_ERROR for printing messages.
1311 * New macros AC_FIND_XTRA, AC_MMAP, AC_SIZEOF_TYPE, AC_PREREQ,
1312 AC_SET_MAKE, AC_ENABLE.
1315 * AC_FIND_X looks for X in more places.
1316 * AC_PROG_INSTALL defaults to install.sh instead of cp, if it's in srcdir.
1317 install.sh is distributed with Autoconf.
1318 * AC_DECLARE_YYTEXT has been removed because it can't work, pending
1319 a rewrite of quoting in AC_DEFINE.
1320 * AC_OUTPUT adds its comments in C format when substituting in C files.
1321 * AC_COMPILE_CHECK protects its ECHO-TEXT argument with double quotes.
1323 ** New or changed command line options:
1324 * configure accepts --enable-FEATURE[=ARG] and --disable-FEATURE options.
1325 * configure accepts --without-PACKAGE, which sets withval=no.
1326 * configure accepts --x-includes=DIR and --x-libraries=DIR.
1327 * Giving --with-PACKAGE no argument sets withval=yes instead of withval=1.
1328 * configure accepts --help, --version, --silent/--quiet, --no-create options.
1329 * configure accepts and ignores most other Cygnus configure options, and
1330 warns about unknown options.
1331 * config.status accepts --help, --version options.
1333 ** File names and other changes:
1334 * Relative srcdir values are not made absolute.
1335 * The values of @prefix@ and @exec_prefix@ and @top_srcdir@ get substituted.
1336 * Autoconf library files are installed in ${datadir}/autoconf, not ${datadir}.
1337 * autoheader optionally copies config.h.top to the beginning of config.h.in.
1338 * The example Makefile dependencies for configure et al. work better.
1339 * Namespace cleanup: all shell variables used internally by Autoconf
1340 have names beginning with `ac_'.
1342 More big improvements are in process for future releases, but have not
1343 yet been (variously) finished, integrated, tested, or documented enough
1346 Major changes in Autoconf 1.7:
1348 * New macro AC_OBSOLETE.
1349 * Bugs in Makefile.in fixed.
1350 * AC_LONG_FILE_NAMES improved.
1352 Major changes in Autoconf 1.6:
1354 * New macro AC_LONG_64_BITS.
1355 * Multiple .h files can be created.
1356 * AC_FIND_X looks for X files directly if it doesn't find xmkmf.
1357 * AC_ALLOCA defines C_ALLOCA if using alloca.c.
1358 * --with-NAME can take a value, e.g., --with-targets=sun4,hp300bsd.
1359 * Unused --no-create option to configure removed.
1360 * autoheader doesn't change the timestamp of its output file if
1361 the file didn't change.
1362 * All macros that look for libraries now use AC_HAVE_LIBRARY.
1363 * config.status checks three optional environment variables to
1364 modify its behavior.
1365 * The usual bug fixes.
1367 Major changes in Autoconf 1.5:
1369 * New macros AC_FIND_X, AC_OFF_T, AC_STAT_MACROS_BROKEN, AC_REVISION.
1370 * autoconf and autoheader scripts have GNU standards conforming
1371 --version and --help options (they print their message and exit).
1374 Major changes in Autoconf 1.4:
1376 * New macros AC_HAVE_POUNDBANG, AC_TIME_WITH_SYS_TIME, AC_LONG_DOUBLE,
1377 AC_GETGROUPS_T, AC_DEFINE_UNQUOTED.
1378 * autoconf and autoheader use the M4 environment variable to determine the
1379 name of the M4 program to use.
1380 * The --macrodir option to autoconf and autoheader specifies the directory
1381 in which acspecific.m4, acgeneral.m4, etc. reside if not the default.
1382 * autoconf and autoheader can take `-' as their file names, which means to
1383 read stdin as input.
1384 * Resulting configure scripts can take a --verbose option which causes them
1385 to print the results of their tests.
1386 * AC_DEFINE quotes its second argument in such a way that spaces, magic
1387 shell characters, etc. will be preserved during various stages of
1388 expansion done by the shell. If you don't want this, use
1389 AC_DEFINE_UNQUOTED instead.
1390 * Much textual processing done with external calls to tr and sed have been
1391 internalized with builtin M4 `patsubst' and `translit' calls.
1392 * AC_OUTPUT doesn't hardwire the file names it outputs. Instead, you can
1393 set the shell variables `gen_files' and `gen_config' to the list of
1394 file names to output.
1395 * AC_DECLARE_YYTEXT does an AC_SUBST of `LEX_OUTPUT_ROOT', which may be
1396 "lex.yy" or "lexyy", depending on the system.
1397 * AC_PROGRAMS_CHECK takes an optional third arg. If given, it is used as
1399 * If AC_ALLOCA chooses alloca.c, it also defines STACK_DIRECTION.
1400 * AC_CONST works much more reliably on more systems.
1403 Major changes in Autoconf 1.3:
1405 configure no longer requires awk for packages that use a config.h.
1406 Support handling --with-PACKAGE options.
1407 New `autoheader' script to create `config.h.in' from `configure.in'.
1408 Ignore troublesome -lucb and -lPW when searching for alloca.
1409 Rename --exec_prefix to --exec-prefix for GNU standards conformance.
1410 Improve detection of STDC library.
1411 Add AC_HAVE_LIBRARY to check for non-default libraries.
1412 Function checking should work with future GNU libc releases.
1414 Major changes in Autoconf 1.2:
1416 The --srcdir option is now usually unnecessary.
1417 Add a file containing sample comments describing CPP macros.
1418 A comment in config.status tells which host it was configured on.
1419 Substituted variable values can now contain commas.
1420 Fix bugs in various feature checks.
1422 Major changes in Autoconf 1.1:
1424 Added AC_STRCOLL macro.
1425 Made AC_GETLOADAVG check for more things.
1426 AC_OUTPUT argument is now optional.
1431 Copyright (C) 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002,
1432 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
1434 This file is part of GNU Autoconf.
1436 GNU Autoconf is free software; you can redistribute it and/or modify
1437 it under the terms of the GNU General Public License as published by
1438 the Free Software Foundation; either version 2, or (at your option)
1441 GNU Autoconf is distributed in the hope that it will be useful,
1442 but WITHOUT ANY WARRANTY; without even the implied warranty of
1443 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1444 GNU General Public License for more details.
1446 You should have received a copy of the GNU General Public License
1447 along with GNU Autoconf; see the file COPYING. If not, write to
1448 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
1449 Boston, MA 02110-1301, USA.