1 GNU Autoconf NEWS - User visible changes.
3 * Major changes in Autoconf 2.62a (2008-??-??)
5 ** Two new quadrigraphs have been introduced: @{:@ for (, and @:}@ for ),
6 allowing the output of unbalanced parantheses in contexts such as
7 AS_HELP_STRING or AT_SETUP that must determine the length of
11 * Major changes in Autoconf 2.62 (2008-04-05) [stable]
12 Released by Eric Blake, based on git versions 2.61a.*.
14 ** Many optimizations have been applied to make overall execution faster.
16 ** Autotest now makes use of shell functions.
18 ** config.status now uses awk instead of sed also for config headers.
20 - As a side effect, AC_DEFINE and AC_DEFINE_UNQUOTED now handle multi-line
21 values, i.e., backslash-newline combinations are handled correctly.
22 Further, for config headers, the total size of values is not limited by
23 the POSIX length limit of text lines any more, only each single line.
25 ** New config variable `top_build_prefix'.
27 ** New Autoconf macros:
28 AC_AUTOCONF_VERSION AC_OPENMP AC_PATH_PROGS_FEATURE_CHECK
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 ** AC_PROG_INSTALL now requires an install program that can install multiple
67 files into a target directory.
69 ** The command 'autoconf -' now correctly processes a file from stdin.
71 ** 'autoreconf -m' now honors $MAKE.
73 ** For all of the directory arguments for 'configure', such as '--prefix'
74 or '--bindir', trailing slashes are stripped. As an example, if
75 tab completion in the user's shell appends trailing slashes, the
76 command './configure --prefix=/usr/' will still result in an
77 expanded libdir value of /usr/lib, not /usr//lib.
79 ** `configure --help=recursive' now works in read-only trees and from
80 unconfigured build trees.
82 ** If precious variables differ only in whitespace, then the cache consistency
83 check warns instead of fails, and reuses the old value.
85 ** AT_BANNER is now documented.
87 ** AT_SETUP now handles macro expansions properly when calculating line
90 ** Autotest now determines $srcdir correctly.
92 ** Testsuites built by autotest now accept a -C/--directory=DIR option
93 to adjust the working directory prior to creating files.
95 ** Autoconf now requires GNU M4 1.4.5 or later. Earlier versions of M4 have
96 a bug in macro tracing that interferes with the interaction between
97 Autoconf and Automake. GNU M4 1.4.11 or later is recommended. The
98 configure search for a working M4 is improved.
100 ** For portability with the eventual M4 2.0, macros should no longer use
101 anything larger than $9 to refer to arguments.
103 ** Documentation for m4sugar is improved.
105 - The following macros were previously available as undocumented
106 interfaces; the macros are now documented as stable interfaces.
108 __oline__ m4_assert m4_bmatch m4_bpatsubsts m4_car m4_case
109 m4_cdr m4_default m4_divert_once m4_divert_pop m4_divert_push
110 m4_divert_text m4_do m4_errprintn m4_fatal m4_flatten
111 m4_ifndef m4_ifset m4_ifval m4_ifvaln m4_location
112 m4_n m4_shiftn m4_strip m4_warn
114 - The following macros were previously available as undocumented
115 interfaces, but had bug fixes or semantic changes as part of this
116 release. Packages that relied on the undocumented behavior
117 should be analyzed to make sure they will still work with the
118 new documented behavior.
120 m4_cmp m4_list_cmp m4_join m4_map m4_map_sep m4_sign
121 m4_text_box m4_text_wrap m4_version_compare
123 - The m4_wrap macro used to have unspecified order, but now
124 guarantees FIFO order. m4_wrap_lifo was added to guarantee LIFO
127 - Packages using the undocumented m4sugar macro m4_PACKAGE_VERSION
128 should consider using the new AC_AUTOCONF_VERSION instead.
130 - m4sugar macros that are not documented in the manual are still
131 deemed experimental, and should not be used outside of Autoconf.
133 ** The m4sugar macros m4_append and m4_append_uniq, first documented in
134 2.60, have been fixed to treat both the string and the separator
135 arguments consistently with regards to quoting. Prior to this fix,
136 m4_append_uniq could mistakenly duplicate entries if the expansion
137 of the separator resulted in a different string (for example, if it
138 contained quotes, a comma, or a macro name). However, it means
139 that programs previously using
140 m4_append([name], [string], [[, ]])
141 are now using a four-character separator instead of the intended
142 comma and space. If you need portability to earlier versions of
143 Autoconf, you can insert the following snippet after AC_INIT but
144 before any other macro expansions, to enforce the new semantics:
145 m4_pushdef([m4_append], [m4_define([$1],
146 m4_ifdef([$1], [m4_defn([$1])[$3]])[$2])])
147 Additionally, m4_append_uniq now takes optional parameters that can
148 be used to take action depending on whether anything was appended,
149 and warns if a non-empty separator occurs within the string being
150 appended, since that can lead to duplicates.
152 ** The following m4sugar macros are new:
153 m4_append_uniq_w m4_apply m4_combine m4_cond m4_count
154 m4_dquote_elt m4_echo m4_expand m4_ignore m4_make_list m4_max
155 m4_min m4_newline m4_shift2 m4_shift3 m4_unquote m4_wrap_lifo
157 ** Warnings are now generated by default when an installer invokes
158 'configure' with an unknown --enable-* or --with-* option.
159 These warnings can be disabled with the new AC_DISABLE_OPTION_CHECKING
160 macro, or by invoking 'configure' with --disable-option-checking.
162 ** Existing obsolete macros
163 The documentation for the following macros is adjusted to make it
164 more clear that they have previously been marked obsolete, as their
165 functionality can be accomplished by other macros. We have no
166 current plans to remove them from Autoconf.
168 AC_ENABLE AC_STRUCT_ST_BLKSIZE AC_STRUCT_ST_RDEV AC_WITH
170 ** Newly obsolete macros
171 The following macros have been marked obsolete, as they only
172 perform a subset of AC_USE_SYSTEM_EXTENSIONS. We have no current
173 plans to remove them.
175 AC_AIX AC_GNU_SOURCE AC_ISC_POSIX AC_MINIX
177 ** AC_C_LONG_DOUBLE is obsolescent.
178 The documentation now says that AC_C_LONG_DOUBLE is obsolescent: it
179 tests for problems that are so old that it is no longer of
180 practical importance on current systems. New programs need not use
181 AC_C_LONG_DOUBLE. We have no current plans to remove it.
183 ** AC_DIAGNOSE, AC_WARNING, and AC_FATAL are obsolescent.
184 The documentation now favors the use of M4sugar macros m4_warn and
185 m4_fatal, since the naming makes it more obvious that the
186 diagnostics are associated with M4 expansion (ie. when running
187 `autoconf'), and offers less confusion with the AC_MSG_ERROR,
188 AC_MSG_FAILURE, and AC_MSG_WARN macros which manage diagnostics
189 when running `configure'. We have no current plans to remove these
193 * Major changes in Autoconf 2.61a (2006-12-11)
195 ** AC_FUNC_FSEEKO was broken in 2.61; it didn't make fseeko and ftello visible
196 on many platforms. This has been fixed.
198 ** AC_FUNC_SETVBUF_REVERSED is now obsolete. It is still defined for backward
199 compatibility but it does nothing. The macro was already
200 obsolescent, as the last systems to have the problem were those
201 based on SVR2, which became obsolete in 1987. The macro had bugs
202 on some modern systems and could no longer be maintained reliably
203 due to lack of ancient systems to test it on.
205 ** config.status now uses awk instead of sed for most substitutions, for speed.
207 - As a side effect multi-line values of substituted variables no
208 longer have a small limit in total size, though for portability
209 each line should not exceed the POSIX length limit for text lines.
211 - It is now documented that Makefile.in should not contain
212 overlapping variable occurrences, e.g., @VAR1@VAR2@.
213 Autoconf's behavior was always iffy in such cases, and the
214 awk implementation has changed the behavior.
216 ** Many uses of 'echo' have been rewritten so that Autoconf-generated
217 scripts have fewer problems with strings or file names containing
218 embedded special characters such as backslash or leading "-". This
219 was implemented by using `printf '%s\n' "$foo"' instead of `echo
220 "$foo"' when printf works. Due to the implementation technique
221 used, Autoconf-generated scripts now run considerably more slowly
222 on ancient implementations lacking printf. However, this should
223 not be a problem, since Autoconf-generated scripts in practice
224 invariably find a more-modern shell these days.
227 * Major changes in Autoconf 2.61 (2006-11-17)
229 ** New macros AC_C_FLEXIBLE_ARRAY_MEMBER, AC_C_VARARRAYS.
231 ** AC_ARG_ENABLE and AC_ARG_WITH now allow '.' in feature and package names.
234 * Major changes in Autoconf 2.60b (2006-10-22)
237 Autoconf-generated shell scripts no longer export BIN_SH, due to
238 configuration hassles with this. Installers who need BIN_SH in
239 their environment should set it before invoking 'configure' and
240 'make'. As far as we know, this affects only Unixware installations.
242 ** Obsolescent macros
243 The documentation now says that the following macros are obsolescent,
244 as they are superseded by Gnulib:
246 AC_FUNC_FNMATCH AC_FUNC_FNMATCH_GNU AC_FUNC_GETLOADVG AC_REPLACE_FNMATCH
248 New programs should use the Gnulib counterparts of these macros.
249 We have no current plans to remove them from Autoconf.
251 ** AC_COMPUTE_INT no longer caches or reports results.
253 ** AC_CHECK_DECL now also works with aggregate objects.
255 ** AC_USE_SYSTEM_EXTENSIONS now defines _TANDEM_SOURCE for NonStop platforms.
257 ** GNU M4 1.4.7 or later is now recommended.
260 New M4sugar macro, which is more secure than the POSIX M4 maketemp.
263 Now an alias for m4_mkstemp.
265 * Major changes in Autoconf 2.60a (2006-08-25)
267 ** GNU M4 1.4.6 or later is now recommended.
269 ** The check for C99 now tests for varargs macros, as documented.
270 It also tests that the preprocessor supports 64-bit integers.
272 ** Autoconf now uses constructs like "#ifdef HAVE_STDLIB_H" rather than
273 "#if HAVE_STDLIB_H", so that it now works with "gcc -Wundef -Werror".
275 ** The functionality of the undocumented _AC_COMPUTE_INT is now provided
276 by a public and documented macro, AC_COMPUTE_INT. The parameters to the
277 two macros are different, so autoupdate will not change the old private name
278 to the new one. _AC_COMPUTE_INT may be removed in a future release.
280 ** AC_TYPE_LONG_LONG_INT and AC_TYPE_UNSIGNED_LONG_LONG_INT now require
281 that long long types be at least 64 bits wide, as C99 and tradition
282 requires. Formerly, they accepted implementations of any width.
285 * Major changes in Autoconf 2.60
287 Released 2006-06-23, by Ralf Wildenhues.
289 ** Autoconf no longer depends on whether m4wrap is FIFO (as Posix requires)
290 or LIFO (as in GNU M4 1.4.x). GNU M4 2.0 is expected to conform to Posix
291 here, so m4wrap/m4_wrap users should no longer depend on LIFO behavior.
293 ** Provide a way to turn off warnings about the changed directory variables.
295 * Major changes in Autoconf 2.59d
297 Released 2006-06-05, by Ralf Wildenhues.
299 ** GNU make now recommended for VPATH builds
300 INSTALL now suggests VPATH builds (e.g., "sh ../srcdir/configure")
301 only if you use GNU make. In practice, other 'make' implementations
302 have too many subtle incompatibilities in their support for VPATH.
303 Many packages (including Autoconf itself) are portable to other
304 'make' implementations, but some packages are not, and recommending
305 GNU make keeps the installation instructions simpler.
307 ** Even more safety checks for the new Directory variables:
308 Warn about suspicious `${datarootdir}' found in config files output.
310 ** AC_TRY_COMMAND, AC_TRY_EVAL, ac_config_guess, ac_config_sub, ac_configure
311 These never-documented macros and variables have been marked with
312 comments saying that they may be removed in a future release,
313 because their use can lead to unintended code being executed.
314 If you need functionality that only these macros or variables
315 currently supply, please write bug-autoconf@gnu.org.
317 ** AC_SUBST, AC_DEFINE
318 Literal arguments to these are passed to m4_pattern_allow now.
321 Passing 'ac_cv_prog_cc_stdc=no' to 'configure' now sets ac_cv_prog_cc_c99
322 and ac_cv_prog_cc_c89 to 'no' as well, for backward compatibility with
323 obsolete K&R tests in the Automake test suite.
332 Now more robust with special characters in file names, or when
333 multiple processes create the same directory at the same time.
335 ** Obsolescent macros
336 The documentation now says that the following macros are obsolescent:
337 they test for problems that are so old that they are no longer of
338 practical importance on current systems.
340 AC_C_BACKSLASH_A AC_FUNC_MEMCMP AC_HEADER_DIRENT
341 AC_C_CONST AC_FUNC_SELECT_ARGTYPES AC_HEADER_STAT
342 AC_C_PROTOTYPES AC_FUNC_SETPGRP AC_HEADER_STDC
343 AC_C_STRINGIZE AC_FUNC_SETVBUF_REVERSED AC_HEADER_SYS_WAIT
344 AC_C_VOLATILE AC_FUNC_STAT AC_HEADER_TIME
345 AC_FUNC_CLOSEDIR_VOID AC_FUNC_STRFTIME AC_ISC_POSIX
346 AC_FUNC_GETPGRP AC_FUNC_UTIME_NULL AC_PROG_GCC_TRADITIONAL
347 AC_FUNC_LSTAT AC_FUNC_VPRINTF AC_STRUCT_TM
349 New programs need not use these macros. We have no current plans to
353 For compatibility with future Libtool 2.0, autoreconf will invoke
354 libtoolize with the option `--ltdl' now, if LT_CONFIG_LTDL_DIR is
357 * Major changes in Autoconf 2.59c
359 Released 2006-04-12, by Ralf Wildenhues.
361 ** The configure command now redirects standard input from /dev/null,
362 to help avoid problems with subsidiary commands that might mistakenly
363 read standard input. AS_ORIGINAL_STDIN_FD points to the original
364 standard input before this redirection, if you really want configure to
365 read from standard input.
367 ** Directory variables adjusted to recent changes in the GNU Coding Standards.
368 The following directory variables are new:
370 datarootdir read-only architecture-independent data root [PREFIX/share]
371 localedir locale-specific message catalogs [DATAROOTDIR/locale]
372 docdir documentation root [DATAROOTDIR/doc/PACKAGE]
373 htmldir html documentation [DOCDIR]
374 dvidir dvi documentation [DOCDIR]
375 pdfdir pdf documentation [DOCDIR]
376 psdir ps documentation [DOCDIR]
378 The following variables have new default values:
380 datadir read-only architecture-independent data [DATAROOTDIR]
381 infodir info documentation [DATAROOTDIR/info]
382 mandir man documentation [DATAROOTDIR/man]
384 This means that if you use any of `@datadir@', `@infodir@', or
385 `@mandir@' in a file, you will have to ensure `${datarootdir}' is
386 defined in this file. As a temporary measure, if any of those are
387 found but no mention of `datarootdir', the substitutions will be
388 replaced with values that do not contain `${datarootdir}', and a
389 warning will be issued.
391 ** @top_builddir@ is now a dir name: it is always nonempty and doesn't have
392 a trailing slash. Similar change will be made to ac_top_builddir in a
393 future release; the old style value, which matches (../)*, is (and will
394 continue to be) available as ac_top_build_prefix.
397 New macro to check for support of 'typeof' syntax a la GNU C.
399 ** AC_CHECK_DECLS_ONCE, AC_CHECK_FUNCS_ONCE, AC_CHECK_HEADERS_ONCE
400 New "once-only" variants of commonly-used macros, to make 'configure'
401 smaller and faster in common cases.
404 New macro to check for strtold with C99 semantics.
407 New macro that lets builder disable assertions at 'configure'-time.
410 Now checks for X11/Xlib.h and XrmInitialize (X proper) rather than
411 X11/Intrinsic.h and XtMalloc (Xt).
413 ** AC_PRESERVE_HELP_ORDER
414 New macro that causes `configure' to display help strings for AC_ARG_ENABLE
415 and AC_ARG_WITH arguments in one region, in the order defined. The default
416 behavior is to group options of each classes separately.
418 ** AC_PROG_CC, AC_PROG_CXX
419 No longer automatically arrange to declare the 'exit' function of C,
420 when a C++ compiler is used. Standard Autoconf macros no longer use
421 'exit', so this is no longer an issue for them. If you use C++, and
422 want to call 'exit', you'll have to arrange for its declaration
423 yourself. But we now suggest you return from 'main' instead.
425 ** AC_PROG_CC_C89, AC_PROG_CC_C99
426 New macros for ISO C99 support. AC_PROG_CC_C89 and AC_PROG_CC_C99
427 check for ANSI C89 and ISO C99 support respectively.
430 Has been unobsoleted, and will check if the compiler supports ISO
431 C99, falling back to ANSI C89 if not. ac_cv_prog_cc_stdc is
432 retained for backwards compatibility, assuming the value of
433 ac_cv_prog_cc_c99 or ac_cv_prog_cc_c89 (whichever is valid, in
436 ** AC_STRUCT_DIRENT_D_INO, AC_STRUCT_DIRENT_D_TYPE
437 New macros for checking commonly-used members of struct dirent.
440 The substituted value can now contain newlines.
443 The substitution now occurs only when @variable@ is on a line by itself,
444 optionally surrounded by spaces and tabs. The whole line is replaced.
446 ** AC_TYPE_LONG_DOUBLE, AC_TYPE_LONG_DOUBLE_WIDER
447 New macros to check for long double, and whether it is wider than double.
448 The old macro AC_C_TYPE_LONG_DOUBLE has been marked as obsolete;
449 applications should switch to the new macro.
451 ** AC_TYPE_INT8_T, AC_TYPE_INT16_T, AC_TYPE_INT32_T, AC_TYPE_INT64_T,
452 AC_TYPE_INTMAX_T, AC_TYPE_INTPTR_T, AC_TYPE_LONG_LONG_INT, AC_TYPE_SSIZE_T,
453 AC_TYPE_UINT8_T, AC_TYPE_UINT16_T, AC_TYPE_UINT32_T, AC_TYPE_UINT64_T,
454 AC_TYPE_UINTMAX_T, AC_TYPE_UINTPTR_T, AC_TYPE_UNSIGNED_LONG_LONG_INT
455 New macros to check for C99 and POSIX types.
457 ** AC_USE_SYSTEM_EXTENSIONS
458 New macro to enable extensions to Posix.
461 New macro which is defined to the name of the first declared config header
462 or undefined if no config headers have been declared yet.
465 The macro correctly handles quadrigraphs now.
467 ** AS_BOURNE_COMPATIBLE, AS_SHELL_SANITIZE, AS_CASE
468 These macros are new or published now.
471 New macro for copyright notices in testsuite files.
473 ** ALLOCA, LIBOBJS, LTLIBOBJS
474 Object names added to these variables are now prefixed with `${LIBOBJDIR}',
475 as in `${LIBOBJDIR}alloca.o'. LIBOBJDIR is meant to be defined from
476 `Makefile.in' in case the object files lie in a different directory.
477 The LIBOBJDIR feature is experimental.
480 Supports --no-recursive now.
482 ** New macros to support Erlang/OTP.
483 New macros for configuring paths to Erlang tools and libraries:
484 AC_ERLANG_PATH_ERLC, AC_ERLANG_NEED_ERLC, AC_ERLANG_PATH_ERL,
485 AC_ERLANG_NEED_ERL, AC_ERLANG_CHECK_LIB, AC_ERLANG_SUBST_ROOT_DIR,
486 AC_ERLANG_SUBST_LIB_DIR.
488 New macros for configuring installation of Erlang libraries:
489 AC_ERLANG_SUBST_INSTALL_LIB_DIR, AC_ERLANG_SUBST_INSTALL_LIB_SUBDIR.
491 ** The manual now mentions Gnulib more prominently.
493 ** New macros to support Objective C.
494 AC_PROG_OBJC, AC_PROG_OBJCPP.
496 * Major changes in Autoconf 2.59b
498 Released 2004-08-20, by Paul Eggert.
501 New macro that computes the default alignment of a type.
503 ** AC_CHECK_TOOL, AC_PATH_TOOL, AC_CHECK_TOOLS
504 When cross-compiling, these macros will give a warning if the tool
505 is not prefixed. In the future, unprefixed cross tools will not
506 be detected; please consult the info documentation for information
507 about the reason of this change.
509 ** AC_CHECK_TARGET_TOOL, AC_PATH_TARGET_TOOL, AC_CHECK_TARGET_TOOLS
510 New macros that detect programs whose name is prefixed with the
511 target type, if the build type and target type are different.
513 ** AC_REQUIRE_AUX_FILE
514 New trace macro that declares expected auxiliary files.
517 New macro that tests for a grep program that accepts as a long a line
520 ** AC_PROG_EGREP, AC_PROG_FGREP
521 These macros now require AC_PROG_GREP, and try EGREP="$GREP -E" and
522 FGREP="$GREP -F" respectively if possible, or else run a path search for
523 a program that accepts as long a line as possible.
526 New macro that tests for a sed program that truncates as few characters
529 * Major changes in Autoconf 2.59
531 Released 2003-11-04, by Akim Demaille
533 ** ac_abs_builddir etc.
534 Absolute file names were actually relative in 2.58.
536 * Major changes in Autoconf 2.58
538 Released 2003-11-04, by Akim Demaille
541 core.* files are no longer removed, as they may be valid user files.
543 ** autoreconf and auxiliary directory
544 Autoreconf creates the auxiliary directory if needed. This is
545 especially useful for initial "bootstrapping" of fresh CVS checkouts.
547 ** AC_CONFIG_MACRO_DIR
548 Use this macro to declare the directory for local M4 macros for aclocal.
551 No longer includes twice the same file in LIBOBJS if invoked
554 ** AC_CONFIG_COMMANDS
555 The directory for its first argument is automatically created. For
558 AC_CONFIG_COMMANDS([src/modules.hh], [...])
560 $top_builddir/src/ is created if needed.
562 ** Autotest and local.at
563 The optional file local.at is always included in Autotest test suites.
566 The warnings are always issued, including with cached runs.
567 This became a significant problem since aclocal and automake can
568 run autoconf behind the scene.
570 ** autoheader warnings
571 The warnings of autoheader can be turned off, using --warning.
572 For instance, -Wno-obsolete disables the complaints about acconfig.h
573 and other deprecated constructs.
576 AC_C_RESTRICT, AC_INCLUDES_DEFAULT, AC_LANG_ASSERT, AC_LANG_WERROR,
579 ** AC_DECL_SYS_SIGLIST
583 Now checks that mktime is the inverse of localtime.
585 ** Improve DJGPP portability
586 The Autoconf tools and configure behave better under DJGPP.
588 ** Present But Cannot Be Compiled
589 New FAQ section dedicated to the mystic
591 configure: WARNING: pi.h: present but cannot be compiled
592 configure: WARNING: pi.h: check for missing prerequisite headers?
593 configure: WARNING: pi.h: proceeding with the preprocessor's result
596 ** Concurrent executions of autom4te
597 autom4te now locks its internal files, which enables concurrent
598 executions of autom4te, likely to happen if automake, autoconf,
599 autoheader etc. are run simultaneously.
602 Use of Libtool 1.5 and higher is encouraged. Compatibility with
603 Libtool pre-1.4 is not checked.
606 Testsuites no longer rerun failed tests in verbose mode; instead,
607 failures are logged while the test is run.
609 In addition, expected failures can be marked as such.
611 * Major changes in Autoconf 2.57
613 Released 2002-12-03 by Paul Eggert.
615 Bug fixes for problems with AIX linker, with freestanding C compilers,
616 with GNU M4 limitations, and with obsolete copies of GNU documents.
618 The Free Documentation License has been upgraded from 1.1 to 1.2.
620 * Major changes in Autoconf 2.56
622 Released 2002-11-15 by Akim Demaille.
624 One packaging problem fixed (config/install-sh was not executable).
626 * Major changes in Autoconf 2.55
628 Released 2002-11-14 by Akim Demaille.
632 Have your configure.ac checked by autoscan ("autoscan").
633 Try the warning options ("autoreconf -fv -Wall").
637 - AC_CHECK_HEADER, AC_CHECK_HEADERS
638 More information on proper use.
640 - Writing Test Programs
642 This sections explains how to write good test sources to use with
643 AC_COMPILE_IFELSE etc. It documents AC_LANG_PROGRAM and so forth.
645 - AC_FOO_IFELSE vs. AC_TRY_FOO
647 Explains why Autoconf moves from AC_TRY_COMPILE etc. to
648 AC_COMPILE_IFELSE and AC_LANG_PROGRAM etc.
652 - Is more robust to different Gettext installations.
654 - Produces messages (when --verbose) to be understood by Emacs'
657 - Supports -W/--warnings.
660 Once the GNU Build System reinstalled, run `./config.status
661 --recheck && ./config.status && make' if possible.
665 - Supports --cache, and --no-cache.
667 - ~/.autom4te.cfg makes it possible to disable the caching mechanism
668 (autom4te.cache). See `Customizing autom4te' in the documentation.
675 Support for the obsoleted options -m, --macrodir, -l, --localdir is
676 dropped in favor of the safer --include/--prepend-include scheme.
681 AC_COMPILER_IFELSE, AC_FUNC_MBRTOWC, AC_HEADER_STDBOOL,
682 AC_LANG_CONFTEST, AC_LANG_SOURCE, AC_LANG_PROGRAM, AC_LANG_CALL,
683 AC_LANG_FUNC_TRY_LINK, AC_MSG_FAILURE, AC_PREPROC_IFELSE.
686 Obsoleted macros are kept for Autoconf backward compatibility, but
687 should be avoided in configure.ac. Running autoupdate is advised.
690 - AC_DEFINE/AC_DEFINE_UNQUOTED
692 We have to stop using the old compatibility scheme --that tried to
693 avoid useless backslashes-- because Libtool 1.4.3 contains a
695 AC_DEFINE([error_t], [int],
696 [Define to a type to use for \`error_t' if it is not
697 otherwise available.])
699 We have to quote the single quotes and backslashes with \. The old
700 compatibility scheme saw that ` was backslashed, and therefore did
701 not quote the single quote... Failure. Hence, Autoconf 2.54 is not
702 compatible with Libtool. Autoconf 2.55 is, but in some cases might
703 produce more \ than wanted.
705 Please, note that in the future the same problem will happen with
706 AC_MSG_*: use `autoreconf -f -Wall'.
710 - Portability of the Autoconf package to Solaris.
712 - Spurious warnings caused by config.status.
713 This bug is benign, but painful: on some systems (typically
714 FreeBSD), warnings such as:
716 config.status: creating Makefile
717 mv: Makefile: set owner/group (was: 1357/0): Operation not permitted
719 could be issued. This is fixed.
722 Simultaneous executions of config.status are possible again.
724 - Precious variables accumulation
726 config.status could stack several copies of the precious variables
730 ** Plans for later versions
734 The compatibility hooks with the old scheme will be completely
735 removed. Please, advice/use `--build', `--host', and `--target'
738 - AC_CHECK_HEADER, AC_CHECK_HEADERS
740 The tests will be stricter, please make sure your invocations are
745 Shell functions will gradually be introduced, probably starting with
746 Autotest. If you know machines which are in use that you suspect
747 *not* to support shell functions, please run the test suite of
748 Autoconf 2.55 on it, and report the results to
749 bug-autoconf@gnu.org.
753 Special characters in AC_MSG_* need not be quoted. Currently,
754 Autoconf has heuristics to decide when a string is escaped, or has
755 to be escaped. This scheme is fragile, and will be removed; the
756 only risk is uglified messages. Please, run `autoreconf -f -Wall'
757 to find occurrences that will be affected.
759 * Major changes in Autoconf 2.54
761 Released 2002-09-13 by Akim Demaille.
765 - autoreconf no longer changes the version of the gettext/po/intl
766 support files. It now adds the files the correspond to the
767 AM_GNU_GETTEXT_VERSION declared in configure.ac.
769 Warning: It now relies on the 'autopoint' program, which is part
770 of GNU gettext 0.11.4 and newer.
772 Please note that you need to have a GNU gettext version that
773 corresponds at least to the AM_GNU_GETTEXT_VERSION declared
774 in configure.ac. You can upgrade to newer GNU gettext versions,
775 though, without needing to change configure.ac.
777 - The -I DIR or --include=DIR option now appends DIR to the include path
778 instead of prepending; this is for consistency with other GNU tools.
779 The new -B DIR or --prepend-include=DIR option has the old behavior.
784 Now handles all the gory details about LIBOBJS and LTLIBOBJS.
785 Please, remove lines such as
787 # This is necessary so that .o files in LIBOBJS are also
788 # built via the ANSI2KNR-filtering rules.
789 LIBOBJS=`echo $LIBOBJS|sed 's/\.o /\$U.o /g;s/\.o$/\$U.o/'`
791 and read the `AC_LIBOBJ vs LIBOBJS' section. Do not define U in
792 your Makefiles either.
794 - AC_CONFIG_LINKS now makes copies if it can't make links.
796 - AC_FUNC_FNMATCH now tests only for POSIX compatibility, reverting to
797 Autoconf 2.13 behavior. The new macro AC_FUNC_FNMATCH_GNU also
798 tests for GNU extensions to fnmatch, and replaces fnmatch if needed.
800 - AC_FUNC_SETVBUF_REVERSED no longer fails when cross-compiling.
802 - AC_PROG_CC_STDC is integrated into AC_PROG_CC.
804 - AC_PROG_F77 default search no longer includes cf77 and cfg77.
808 AC_C_BACKSLASH_A, AC_CONFIG_LIBOBJ_DIR, AC_GNU_SOURCE,
809 AC_PROG_EGREP, AC_PROG_FGREP, AC_REPLACE_FNMATCH,
810 AC_FUNC_FNMATCH_GNU, AC_FUNC_REALLOC, AC_TYPE_MBSTATE_T.
813 looks for getloadavg.c in the CONFIG_LIBOBJ_DIR.
816 Now defines HAVE_MALLOC to 0 if `malloc' does not work, and asks
817 for an AC_LIBOBJ replacement.
821 - Spurious complaints from `m4_bmatch' about invalid regular
822 expressions are suppressed.
824 - Empty top_builddirs are properly handled.
826 - AC_CHECK_MEMBER works correctly when the member is an aggregate.
829 Now colon in the optional path arguments are properly handled.
831 ** Improved portability
833 - Both Autoconf the package, and the scripts it produces, should run
834 more reliably with Zsh. Bear in mind it is the default Bourne shell
837 - Autoconf and the scripts it produces no longer assume the existence of
838 the obsolescent commands egrep and fgrep.
842 - Limitations of Make
846 The GNATS base moved to
847 http://bugs.gnu.org/cgi-bin/gnatsweb.pl?database=autoconf
848 (It is no longer available, though.)
853 Now contains the list of ouput variables and files (AC_SUBST,
856 * Major changes in Autoconf 2.53
858 Released 2002-03-08 by Akim Demaille.
862 Perl 5.005_03 or later is required: autom4te is written in Perl and is
863 needed by autoconf. autoheader, autoreconf, ifnames, and autoscan are
869 Argument requirements, output variables, defined macros.
870 - M4sugar, M4sh, Autotest
872 - Double quoting macros
873 AC_TRY_CPP, AC_TRY_COMPILE, AC_TRY_LINK and AC_TRY_RUN.
875 The Autoconf manual is now distributed under the terms of the GNU FDL.
876 - Section `Hosts and Cross-Compilation'
877 Explains the rationale for the 2.5x changes in the cross-compilation
878 chain, and in the relationships between build, host, and target
880 Emphasizes that `cross-compilation' == `--host is given'.
881 If you are working on compilers etc., be sure to read this section.
882 - Section `AC_LIBOBJ vs. LIBOBJS'
883 Explains why assigning LIBOBJS directly is now an error.
884 Details how to update the code.
889 Now used instead of hard coded line numbers.
890 This eases the comparison of `configure's, and diminishes the
891 pressure over control version archives.
892 Automatic replacement for shells that don't support this feature.
893 - New output variables
894 @builddir@, @top_builddir@, @abs_srcdir@, @abs_top_srcdir@, @abs_builddir@,
899 Autoconf and Autotest modes are provided.
904 New, used by the Autoconf suite to cache and speed up most processing.
906 Supported by autom4te, autoconf and autoheader.
908 Replaces --autoconf-dir and --localdir in autoconf, autoheader,
909 autoupdate, and autoreconf.
911 No longer passes --cygnus, --foreign, --gnits, --gnu, --include-deps:
912 automake options are to be given via AUTOMAKE_OPTIONS.
914 Runs gettextize and libtoolize when appropriate.
916 --m4dir is no longer supported.
918 Now runs only in the specified directories, defaulting to `.',
919 but understands AC_CONFIG_SUBDIRS for dependent directories.
920 Before, it used to run on all the `configure.ac' found in the
922 Independent packages are properly updated.
926 - The top level $prefix is propagated to the AC_CONFIG_SUBDIRS configures.
928 Under the user pressure, $? is finally available. Probably a mistake.
929 - AC_F77_LIBRARY_LDFLAGS now supports the HP/UX f90 compiler.
930 - Precious variables accumulation
931 config.status could stack several copies of the precious variables
933 - AC_PATH_PROG and family.
934 Works properly when given a literal path.
936 Somewhere since 2.13, the result had been reversed.
940 - AC_C_BIGENDIAN supports the cross-compiling case.
941 - AC_C_BIGENDIAN accepts ACTION-IF-TRUE, ACTION-IF-FALSE, and
942 ACTION-IF-UNKNOWN arguments. All are facultative, and the default
943 for ACTION-IF-TRUE is to define WORDS_BIGENDIAN like AC_C_BIGENDIAN
945 - AC_C_LONG_DOUBLE now succeeds only if `long double' has more range or
946 precision than `double'.
951 It now defines the preprocessor symbols PACKAGE_NAME,
952 PACKAGE_TARNAME, PACKAGE_VERSION, PACKAGE_STRING, and
956 Admits a fourth optional parameter: the tar name.
958 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS.
959 Provide the user with srcdir, ac_srcdir, ac_top_srcdir, ac_builddir,
960 ac_top_builddir, ac_abs_srcdir, ac_abs_top_srcdir, ac_abs_builddir,
963 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS and AC_OUTPUT.
964 Are much less expensive when using long lists of files.
967 Works with shell variables, and non alphanumeric names.
971 - AC_FUNC_STRERROR_R now sets STRERROR_R_CHAR_P, not HAVE_WORKING_STRERROR_R,
972 because POSIX 1003.1-200x draft 7 says strerror_r returns int, not char *.
974 - AC_FUNC_STRTOD substitutes POW_LIB.
979 * Major changes in Autoconf 2.52
981 Released 2001-07-18 by Akim Demaille.
986 This feature was present in autoconf 2.50 but was not documented.
987 For example, `@<:@' is translated to `[' just before output. This
988 is useful when writing strings that contain unbalanced quotes, or
989 other hard-to-quote constructs.
990 - m4_pattern_forbid, m4_pattern_allow
991 - Tips for upgrading from 2.13.
992 - Using autoscan to maintain a configure.ac.
995 - Now include stdint.h.
996 - sys/types.h and sys/stat.h are guarded.
997 - strings.h is included if available, and not conflicting with string.h.
1000 - The test suite is more robust and presents less false failures.
1001 - Invocation of GNU M4 now robust to POSIXLY_CORRECT.
1002 - configure accepts --prefix='' again.
1003 - AC_CHECK_LIB works properly when its first argument is not a
1005 - HAVE_INTTYPES_H is defined only if not conflicting with sys/types.h.
1006 - build_, host_, and target_alias are AC_SUBST as in 2.13.
1007 - AC_ARG_VAR properly propagates precious variables inherited from the
1008 environment to ./config.status.
1009 - Using --program-suffix/--program-prefix is portable.
1010 - Failures to detect the default compiler's output extension are less
1012 - `config.status foo' works properly when `foo' depends on variables
1013 set in an AC_CONFIG_THING INIT-CMD.
1014 - autoheader is more robust to broken input.
1015 - Fixed Fortran name-mangling and link tests on a number of systems,
1016 e.g. NetBSD; see AC_F77_DUMMY_MAIN, below.
1019 - AC_CHECK_HEADER and AC_CHECK_HEADERS support a fourth argument to
1020 specify pre-includes. In this case, the headers are compiled with
1021 cc, not merely preprocessed by cpp. Therefore it is the _usability_
1022 of a header which is checked for, not just its availability.
1023 - AC_ARG_VAR refuses to run configure when precious variables have
1025 - Versions of compilers are dumped in the logs.
1026 - AC_CHECK_TYPE recognizes use of `foo_t' as a replacement type.
1029 - AC_PATH_XTRA only adds -ldnet to $LIBS if it's needed to link.
1030 - AC_FUNC_WAIT3 and AC_SYS_RESTARTABLE_SYSCALLS are obsoleted.
1031 - AM_FUNC_ERROR_AT_LINE, AM_FUNC_FNMATCH, AM_FUNC_MKTIME,
1032 AM_FUNC_OBSTACK, and AM_FUNC_STRTOD are now activated.
1033 Be sure to read `Upgrading from Version 2.13' to understand why
1034 running `autoupdate' is needed.
1035 - AC_F77_DUMMY_MAIN, AC_F77_MAIN: new macros to detect whether
1036 a main-like routine is required/possible when linking C/C++ with
1037 Fortran. Users of e.g. AC_F77_WRAPPERS should be aware of these.
1038 - AC_FUNC_GETPGRG behaves better when cross-compiling.
1040 * Major changes in Autoconf 2.51
1041 There was no release of Autoconf 2.51 since some packagers had used
1042 this version number without permission to ship intermediary versions
1043 of 2.50. The version was skipped to avoid confusion.
1045 * Major changes in Autoconf 2.50
1047 Released 2001-05-21 by Akim Demaille.
1049 ** Lots of bug fixes
1050 There have been far too many to enumerate them here. Check out
1051 ChangeLog if you really want to know more.
1053 ** Improved documentation
1054 In particular, portability issues are better covered.
1057 All the standard GNU Makefile targets are supported. The layout has
1058 changed: m4/ holds the M4 extensions Autoconf needs for its
1059 configuration, doc/ contains the documentation, and tests/ contains
1062 ** Man pages are provided
1063 For autoconf, autoreconf, autoupdate, autoheader, autoscan, ifnames,
1064 config.guess, config.sub.
1068 Provides a safe and powerful means to trace the macro uses. This
1069 provide the parsing layer for tools which need to `study'
1073 Specify what category of warnings should be enabled.
1075 - When recursing into subdirectories, try for configure.gnu before
1076 configure to adapt for packages not using autoconf on case-insensitive
1080 More errors are now caught (circular AC_REQUIRE dependencies,
1081 AC_DEFINE in the action part of an AC_CACHE_CHECK, too many pops
1082 etc.). In addition, their location and call stack are given.
1085 autoupdate is much more powerful, and is able to provide the glue code
1086 which might be needed to move from an old macro to its newer
1089 You are strongly encouraged to use it to modernize both your
1090 `configure.in' and your .m4 extension files.
1093 The internal machinery of autoheader has completely changed. As a
1094 result, using `acconfig.h' should be considered to be obsoleted, and
1095 you are encouraged to get rid of it using the AH macros.
1100 ** Fortran 77 compilers
1101 Globally, the support for Fortran 77 is considerably improved.
1103 Support for automatically determining a Fortran 77 compiler's
1104 name-mangling scheme. New CPP macros F77_FUNC and F77_FUNC_ are
1105 provided to wrap C/C++ identifiers, thus making it easier and more
1106 transparent for C/C++ to call Fortran 77 routines, and Fortran 77 to
1107 call C/C++ routines. See the Texinfo documentation for details.
1110 The test suite no longer uses DejaGNU. It should be easy to submit
1111 test cases in this new framework.
1114 - --help, --help=long, -hl
1115 no longer dumps useless items.
1117 lists only specific options.
1118 - --help=recursive, -hr
1119 displays the help of all the embedded packages.
1120 - Remembers environment variables when reconfiguring.
1121 The previous scheme to set envvar before running configure was
1123 what prevented configure from remembering the environment in which
1124 it was run, therefore --recheck was run in an inconsistent
1125 environment. Now, one should run
1127 and then --recheck will work properly. Variables declared with
1128 AC_ARG_VAR are also preserved.
1130 $build defaults to `config.guess`, $host to $build, and then $target
1132 Cross-compilation is a global status of the package, it no longer
1133 depends upon the current language.
1134 Cross compilation is enabled iff the user specified `--host'.
1135 `configure' now fails if it can't run the executables it compiles,
1136 unless cross-compilation is enabled.
1138 The cache file is disabled by default. The new options
1139 `--config-cache', `-C' set the cache to `config.cache'.
1143 Much faster on most architectures.
1144 - concurrent executions
1145 It is safe to use `make -j' with config.status.
1146 - human interface improved
1147 It is possible to invoke
1148 ./config.status foobar
1149 instead of the former form (still valid)
1150 CONFIG_COMMANDS= CONFIG_HEADERS= CONFIG_LINKS= \
1151 CONFIG_FILES=foobar:foo.in:bar.in \
1153 The same holds for configuration headers and links.
1154 You can instantiate unknown files and headers:
1155 ./config.status --header foo.h:foo.h.in --file bar:baz
1156 - has a useful --help
1157 - accepts special file name "-" for stdin/stdout
1162 Specify additional copyright information.
1165 Now expects the identity of the package as argument.
1169 Most macros, if not all, now strictly follow the `one quotation
1170 level' rule. This results in a more predictable expansion.
1173 A sly bug in the AC_REQUIRE machinery, which could produce incorrect
1174 configure scripts, was fixed by Axel Thimm.
1178 Document and ask for the registration of an envvar.
1181 Specifies the file which `configure' should look for when trying to
1182 find the source tree (used to be handled by AC_INIT).
1184 - AC_CONFIG_COMMANDS
1185 To add new actions to config.status. Should be used instead of
1189 Replaces AC_LINK_FILES.
1191 - AC_CONFIG_HEADERS, AC_CONFIG_COMMANDS, AC_CONFIG_SUBDIRS,
1192 AC_CONFIG_LINKS, and AC_CONFIG_FILES
1193 They now obey sh: you should no longer use shell variables as
1194 argument. Instead of
1196 test "$package_foo_enabled" = yes && $my_subdirs="$my_subdirs foo"
1197 AC_CONFIG_SUBDIRS($my_subdirs)
1201 if test "$package_foo_enabled" = yes; then
1202 AC_CONFIG_SUBDIRS(foo)
1206 To format an Autoconf macro's help string so that it looks pretty
1207 when the user executes `configure --help'.
1210 ** Generic Test Macros
1212 The interface of the AC_CHECK families of macros (decl, header,
1213 type, member, func) is now uniform. They support the same set of
1216 - AC_CHECK_DECL, AC_CHECK_DECLS
1217 To check whether a symbol is declared.
1219 - AC_CHECK_SIZEOF, AC_C_CHAR_UNSIGNED.
1220 No longer need a cross-compilation default.
1223 The test it performs is much more robust than previously, and makes
1224 it possible to test builtin types in addition to typedefs.
1225 It is now schizophrenic:
1226 - AC_CHECK_TYPE(TYPE, REPLACEMENT)
1227 remains for backward compatibility, but its use is discouraged.
1228 - AC_CHECK_TYPE(TYPE, IF-FOUND, IF-NOT-FOUND, INCLUDES)
1229 behaves exactly like the other AC_CHECK macros.
1232 Checks whether given types are supported by the system.
1234 - AC_CHECK_MEMBER, AC_CHECK_MEMBERS
1235 Check for given members in aggregates (e.g., pw_gecos in struct
1239 Checks if the compiler supports ISO C, included when needs special
1243 Checking whether the preprocessor indicates missing includes by the
1244 error code. stderr is checked by AC_TRY_CPP only as a fallback.
1247 Takes a language as argument and replaces AC_LANG_C,
1248 AC_LANG_CPLUSPLUS and AC_LANG_FORTRAN77.
1250 - AC_LANG_PUSH, AC_LANG_POP
1251 Are preferred to AC_LANG_SAVE, AC_LANG_RESTORE.
1254 - AC_FUNC_CHOWN, AC_FUNC_MALLOC, AC_FUNC_STRERROR_R,
1255 AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK, AC_FUNC_STAT, AC_FUNC_LSTAT,
1256 AC_FUNC_ERROR_AT_LINE, AC_FUNC_OBSTACK, AC_FUNC_STRTOD, AC_FUNC_FSEEKO.
1260 Sets GETGROUPS_LIBS.
1262 - AC_FUNC_GETLOADAVG
1263 Defines `HAVE_STRUCT_NLIST_N_UN_N_NAME' instead of `NLIST_NAME_UNION'.
1266 Now integrates `AC_DECL_YYTEXT' which is obsoleted.
1269 Arrange for large-file support.
1271 - AC_EXEEXT, AC_OBJEXT
1272 You are no longer expected to use them: their computation is
1273 performed by default.
1275 ** C++ compatibility
1276 Every macro has been revisited in order to support at best CC=c++.
1278 Major changes in Autoconf 2.14:
1279 There was no release of GNU Autoconf 2.14.
1281 Major changes in Autoconf 2.13:
1283 Released 1999-05-01 by Ben Elliston.
1285 * Support for building on Win32 systems where the only available C or
1286 C++ compiler is the Microsoft Visual C++ command line compiler
1287 (`cl'). Additional support for building on Win32 systems which are
1288 using the Cygwin or Mingw32 environments.
1289 * Support for alternative object file and executable file extensions.
1290 On Win32, for example, these are .obj and .exe. These are discovered
1291 using AC_OBJEXT and AC_EXEEXT, which substitute @OBJEXT@ and
1292 @EXEEXT@ in the output, respectively.
1293 * New macros: AC_CACHE_LOAD, AC_CACHE_SAVE, AC_FUNC_SELECT_ARGTYPES,
1294 AC_VALIDATE_CACHED_SYSTEM_TUPLE, AC_SEARCH_LIBS, AC_TRY_LINK_FUNC,
1295 AC_C_STRINGIZE, AC_CHECK_FILE(S), AC_PROG_F77 (and friends).
1296 * AC_DEFINE now has an optional third argument for a description to be
1297 placed in the config header input file (e.g. config.h.in).
1298 * The C++ code fragment compiled for the C++ compiler test had to be
1299 improved to include an explicit return type for main(). This was
1300 causing failures on systems using recent versions of the EGCS C++
1302 * Fixed an important bug in AC_CHECK_TYPE that would cause a configure
1303 script to report that `sometype_t' was present when only `type_t'
1305 * Merge of the FSF version of config.guess and config.sub to modernize
1306 these scripts. Add support for a few new hosts in config.guess.
1307 Incorporate latest versions of install-sh, mkinstalldirs and
1308 texinfo.tex from the FSF.
1309 * autoreconf is capable of running automake if necessary (and
1311 * Support for Fortran 77. See the Texinfo documentation for details.
1312 * Bug fixes and workarounds for quirky bugs in vendor utilities.
1314 Major changes in Autoconf 2.12:
1316 Released 1996-11-26 by David J. MacKenzie
1318 * AC_OUTPUT and AC_CONFIG_HEADER can create output files by
1319 concatenating multiple input files separated by colons, like so:
1320 AC_CONFIG_HEADER(config.h:conf.pre:config.h.in:conf.post)
1321 AC_OUTPUT(Makefile:Makefile.in:Makefile.rules)
1322 The arguments may be shell variables, to compute the lists on the fly.
1323 * AC_LINK_FILES and AC_CONFIG_SUBDIRS may be called multiple times.
1324 * New macro AC_OUTPUT_COMMANDS adds more commands to run in config.status.
1327 Major changes in Autoconf 2.11:
1329 Released November 18th, 1996, by David J. MacKenzie
1331 * AC_PROG_CC and AC_PROG_CXX check whether the compiler works.
1332 They also default CFLAGS/CXXFLAGS to "-g -O2" for gcc, instead of "-g -O".
1333 * AC_REPLACE_FUNCS defines HAVE_foo if the system has the function `foo'.
1334 * AC_CONFIG_HEADER expands shell variables in its argument.
1335 * New macros: AC_FUNC_FNMATCH, AC_FUNC_SETPGRP.
1336 * The "checking..." messages and the source code for test programs that
1337 fail are saved in config.log.
1338 * Another workaround has been added for seds with small command length limits.
1339 * config.sub and config.guess recognize more system types.
1342 Major changes in Autoconf 2.10:
1344 Released May 7th, 1996, by Roland McGrath
1347 * The cache variable names used by `AC_CHECK_LIB(LIB, FUNC, ...)' has
1348 changed: now $ac_cv_lib_LIB_FUNC, previously $ac_cv_lib_LIB.
1350 Major changes in Autoconf 2.9:
1352 Released March 16th, 1996, by Roland McGrath
1356 Major changes in Autoconf 2.8:
1358 Released March 8th, 1996, by Roland McGrath
1362 Major changes in Autoconf 2.7:
1364 Released November 22nd, 1995, by David J. MacKenzie
1368 Major changes in Autoconf 2.6:
1370 Released November 20th, 1995, by David J. MacKenzie
1374 Major changes in Autoconf 2.5:
1376 Released November 17th, 1995, by Roland McGrath
1378 * New configure options --bindir, --libdir, --datadir, etc., with
1379 corresponding output variables.
1380 * New macro: AC_CACHE_CHECK, to make using the cache easier.
1381 * config.log contains the command being run as well as any output from it.
1382 * AC_CHECK_LIB can check for libraries with "." or "/" or "+" in their name.
1383 * AC_PROG_INSTALL doesn't cache a name for install-sh, for sharing caches.
1384 * AC_CHECK_PROG, AC_PATH_PROG, AC_CHECK_PROGS, AC_PATH_PROGS, and
1385 AC_CHECK_TOOL can search a path other than $PATH.
1386 * AC_CHECK_SIZEOF takes an optional size to use when cross-compiling.
1388 Major changes in Autoconf 2.4:
1390 Released June 14th, 1995, by David J. MacKenzie
1392 * Fix a few bugs found by Emacs testers.
1394 Major changes in Autoconf 2.3:
1396 Released March 27th, 1995, by David J. MacKenzie
1398 * Fix the cleanup trap in several ways.
1399 * Handle C compilers that are picky about option placement.
1400 * ifnames gets the version number from the right directory.
1402 Major changes in Autoconf 2.2:
1404 Released March 8th, 1995, by David J. MacKenzie
1406 * The ifnames utility is much faster but requires a "new awk" interpreter.
1407 * AC_CHECK_LIB and AC_HAVE_LIBRARY check and add the new
1408 library before existing libs, not after, in case it uses them.
1409 * New macros: AC_FUNC_GETPGRP, AC_CHECK_TOOL.
1410 * Lots of bug fixes.
1411 * Many additions to the TODO file :-)
1413 Major changes in Autoconf 2.1:
1415 Released November 4th, 1994, by David J. MacKenzie
1418 * More explanations in the manual.
1419 * Fix a spurious failure in the testsuite.
1420 * Clarify some warning messages.
1421 * autoreconf by default only rebuilds configure and config.h.in files
1422 that are older than any of their particular input files; there is a
1423 --force option to use after installing a new version of Autoconf.
1425 Thanks to everybody who's submitted changes and additions to Autoconf!
1426 I've incorporated many of them, and am still considering others for
1427 future releases -- but I didn't want to postpone this release indefinitely.
1429 Caution: don't indiscriminately rebuild configure scripts with
1430 Autoconf version 2. Some configure.in files need minor adjustments to
1431 work with it; the documentation has a chapter on upgrading. A few
1432 configure.in files, including those for GNU Emacs and the GNU C
1433 Library, need major changes because they relied on undocumented
1434 internals of version 1. Future releases of those packages will have
1435 updated configure.in files.
1437 It's best to use GNU M4 1.3 (or later) with Autoconf version 2.
1438 Autoconf now makes heavy use of M4 diversions, which were implemented
1439 inefficiently in GNU M4 releases before 1.3.
1441 Major changes in Autoconf 2.0:
1443 Released October 26th, 1994, by David J. MacKenzie
1445 ** New copyright terms:
1446 * There are no restrictions on distribution or use of configure scripts.
1449 * Autoconf manual is reorganized to make information easier to find
1450 and has several new indexes.
1451 * INSTALL is reorganized and clearer and is now made from Texinfo source.
1454 * autoscan to generate a preliminary configure.in for a package by
1455 scanning its source code for commonly used nonportable functions,
1456 programs, and header files.
1457 * ifnames to list the symbols used in #if and #ifdef directives in a
1459 * autoupdate to update a configure.in to use the version 2 macro names.
1460 * autoreconf to recursively remake configure and configuration header
1461 files in a source tree.
1463 ** Changed utilities:
1464 * autoheader can take pieces of acconfig.h to replace config.h.{top,bot}.
1465 * autoconf and autoheader can look for package-local definition files
1466 in an alternate directory.
1469 * AC_CACHE_VAL to share results of tests between configure runs.
1470 * AC_DEFUN to define macros, automatically AC_PROVIDE them, and ensure
1471 that macros invoked with AC_REQUIRE don't interrupt other macros.
1472 * AC_CONFIG_AUX_DIR, AC_CANONICAL_SYSTEM, AC_CANONICAL_HOST, AC_LINK_FILES to
1473 support deciding unguessable features based on the host and target types.
1474 * AC_CONFIG_SUBDIRS to recursively configure a source tree.
1475 * AC_ARG_PROGRAM to use the options --program-prefix,
1476 --program-suffix, and --program-transform-name to change the names
1477 of programs being installed.
1478 * AC_PREFIX_DEFAULT to change the default installation prefix.
1479 * AC_TRY_COMPILE to compile a test program without linking it.
1480 * AC_CHECK_TYPE to check whether sys/types.h or stdlib.h defines a given type.
1481 * AC_CHECK_LIB to check for a particular function and library.
1482 * AC_MSG_CHECKING and AC_MSG_RESULT to print test results, on a single line,
1483 whether or not the test succeeds. They obsolete AC_CHECKING and AC_VERBOSE.
1484 * AC_SUBST_FILE to insert one file into another.
1485 * AC_FUNC_MEMCMP to check whether memcmp is 8-bit clean.
1486 * AC_FUNC_STRFTIME to find strftime even if it's in -lintl.
1487 * AC_FUNC_GETMNTENT to find getmntent even if it's in -lsun or -lseq.
1488 * AC_HEADER_SYS_WAIT to check whether sys/wait.h is POSIX.1 compatible.
1491 * Many macros renamed systematically, but old names are accepted for
1492 backward compatibility.
1493 * AC_OUTPUT adds the "automatically generated" comment to
1494 non-Makefiles where it finds @configure_input@ in an input file, to
1495 support files with various comment syntaxes.
1496 * AC_OUTPUT does not replace "prefix" and "exec_prefix" in generated
1497 files when they are not enclosed in @ signs.
1498 * AC_OUTPUT allows the optional environment variable CONFIG_STATUS to
1499 override the file name "config.status".
1500 * AC_OUTPUT takes an optional argument for passing variables from
1501 configure to config.status.
1502 * AC_OUTPUT and AC_CONFIG_HEADER allow you to override the input-file names.
1503 * AC_OUTPUT automatically substitutes the values of CFLAGS, CXXFLAGS,
1504 CPPFLAGS, and LDFLAGS from the environment.
1505 * AC_PROG_CC and AC_PROG_CXX now set CFLAGS and CXXFLAGS, respectively.
1506 * AC_PROG_INSTALL looks for install-sh or install.sh in the directory
1507 specified by AC_CONFIG_AUXDIR, or srcdir or srcdir/.. or
1508 srcdir/../.. by default.
1509 * AC_DEFINE, AC_DEFINE_UNQUOTED, and AC_SUBST are more robust and smaller.
1510 * AC_DEFINE no longer prints anything, because of the new result reporting
1511 mechanism (AC_MSG_CHECKING and AC_MSG_RESULT).
1512 * AC_VERBOSE pays attention to --quiet/--silent, not --verbose.
1513 * AC_ARG_ENABLE and AC_ARG_WITH support whitespace in the arguments to
1514 --enable- and --with- options.
1515 * AC_CHECK_FUNCS and AC_CHECK_HEADERS take optional shell commands to
1516 execute on success or failure.
1517 * Checking for C functions in C++ works.
1520 * AC_REMOTE_TAPE and AC_RSH removed; too specific to tar and cpio, and
1521 better maintained with them.
1522 * AC_ARG_ARRAY removed because no one was likely using it.
1523 * AC_HAVE_POUNDBANG replaced with AC_SYS_INTERPRETER, which doesn't
1524 take arguments, for consistency with all of the other specific checks.
1527 * Comes with config.sub and config.guess, and uses them optionally.
1528 * Uses config.cache to cache test results. An alternate cache file
1529 can be selected with the --cache-file=FILE option.
1530 * Uses optional shell scripts $prefix/share/config.site and
1531 $prefix/etc/config.site to perform site or system specific initializations.
1532 * configure saves compiler output to ./config.log for debugging.
1533 * New files autoconf.m4 and autoheader.m4 load the other Autoconf macros.
1534 * acsite.m4 is the new name for the system-wide aclocal.m4.
1535 * Has a DejaGnu test suite.
1537 Major changes in Autoconf 1.11:
1539 * AC_PROG_INSTALL calls install.sh with the -c option.
1540 * AC_SET_MAKE cleans up after itself.
1541 * AC_OUTPUT sets prefix and exec_prefix if they weren't set already.
1542 * AC_OUTPUT prevents shells from looking in PATH for config.status.
1544 Plus a few other bug fixes.
1546 Major changes in Autoconf 1.10:
1548 * autoheader uses config.h.bot if present, analogous to config.h.top.
1549 * AC_PROG_INSTALL looks for install.sh in srcdir or srcdir/.. and
1551 * AC_PROG_CXX looks for cxx as a C++ compiler.
1553 Plus several bugs fixed.
1555 Major changes in Autoconf 1.9:
1557 * AC_YYTEXT_POINTER replaces AC_DECLARE_YYTEXT.
1558 * AC_SIZEOF_TYPE generates the cpp symbol name automatically,
1559 and autoheader generates entries for those names automatically.
1560 * AC_FIND_X gets the result from xmkmf correctly.
1561 * AC_FIND_X assumes no X if --without-x was given.
1562 * AC_FIND_XTRA adds libraries to the variable X_EXTRA_LIBS.
1563 * AC_PROG_INSTALL finds OSF/1 installbsd.
1565 Major changes in Autoconf 1.8:
1568 * New macros AC_LANG_C, AC_LANG_CPLUSPLUS, AC_LANG_SAVE, AC_LANG_RESTORE,
1569 AC_PROG_CXX, AC_PROG_CXXCPP, AC_REQUIRE_CPP
1570 for checking both C++ and C features in one configure script.
1571 * New macros AC_CHECKING, AC_VERBOSE, AC_WARN, AC_ERROR for printing messages.
1572 * New macros AC_FIND_XTRA, AC_MMAP, AC_SIZEOF_TYPE, AC_PREREQ,
1573 AC_SET_MAKE, AC_ENABLE.
1576 * AC_FIND_X looks for X in more places.
1577 * AC_PROG_INSTALL defaults to install.sh instead of cp, if it's in srcdir.
1578 install.sh is distributed with Autoconf.
1579 * AC_DECLARE_YYTEXT has been removed because it can't work, pending
1580 a rewrite of quoting in AC_DEFINE.
1581 * AC_OUTPUT adds its comments in C format when substituting in C files.
1582 * AC_COMPILE_CHECK protects its ECHO-TEXT argument with double quotes.
1584 ** New or changed command line options:
1585 * configure accepts --enable-FEATURE[=ARG] and --disable-FEATURE options.
1586 * configure accepts --without-PACKAGE, which sets withval=no.
1587 * configure accepts --x-includes=DIR and --x-libraries=DIR.
1588 * Giving --with-PACKAGE no argument sets withval=yes instead of withval=1.
1589 * configure accepts --help, --version, --silent/--quiet, --no-create options.
1590 * configure accepts and ignores most other Cygnus configure options, and
1591 warns about unknown options.
1592 * config.status accepts --help, --version options.
1594 ** File names and other changes:
1595 * Relative srcdir values are not made absolute.
1596 * The values of @prefix@ and @exec_prefix@ and @top_srcdir@ get substituted.
1597 * Autoconf library files are installed in ${datadir}/autoconf, not ${datadir}.
1598 * autoheader optionally copies config.h.top to the beginning of config.h.in.
1599 * The example Makefile dependencies for configure et al. work better.
1600 * Namespace cleanup: all shell variables used internally by Autoconf
1601 have names beginning with `ac_'.
1603 More big improvements are in process for future releases, but have not
1604 yet been (variously) finished, integrated, tested, or documented enough
1607 Major changes in Autoconf 1.7:
1609 * New macro AC_OBSOLETE.
1610 * Bugs in Makefile.in fixed.
1611 * AC_LONG_FILE_NAMES improved.
1613 Major changes in Autoconf 1.6:
1615 * New macro AC_LONG_64_BITS.
1616 * Multiple .h files can be created.
1617 * AC_FIND_X looks for X files directly if it doesn't find xmkmf.
1618 * AC_ALLOCA defines C_ALLOCA if using alloca.c.
1619 * --with-NAME can take a value, e.g., --with-targets=sun4,hp300bsd.
1620 * Unused --no-create option to configure removed.
1621 * autoheader doesn't change the timestamp of its output file if
1622 the file didn't change.
1623 * All macros that look for libraries now use AC_HAVE_LIBRARY.
1624 * config.status checks three optional environment variables to
1625 modify its behavior.
1626 * The usual bug fixes.
1628 Major changes in Autoconf 1.5:
1630 * New macros AC_FIND_X, AC_OFF_T, AC_STAT_MACROS_BROKEN, AC_REVISION.
1631 * autoconf and autoheader scripts have GNU standards conforming
1632 --version and --help options (they print their message and exit).
1635 Major changes in Autoconf 1.4:
1637 * New macros AC_HAVE_POUNDBANG, AC_TIME_WITH_SYS_TIME, AC_LONG_DOUBLE,
1638 AC_GETGROUPS_T, AC_DEFINE_UNQUOTED.
1639 * autoconf and autoheader use the M4 environment variable to determine the
1640 name of the M4 program to use.
1641 * The --macrodir option to autoconf and autoheader specifies the directory
1642 in which acspecific.m4, acgeneral.m4, etc. reside if not the default.
1643 * autoconf and autoheader can take `-' as their file names, which means to
1644 read stdin as input.
1645 * Resulting configure scripts can take a --verbose option which causes them
1646 to print the results of their tests.
1647 * AC_DEFINE quotes its second argument in such a way that spaces, magic
1648 shell characters, etc. will be preserved during various stages of
1649 expansion done by the shell. If you don't want this, use
1650 AC_DEFINE_UNQUOTED instead.
1651 * Much textual processing done with external calls to tr and sed have been
1652 internalized with builtin M4 `patsubst' and `translit' calls.
1653 * AC_OUTPUT doesn't hardwire the file names it outputs. Instead, you can
1654 set the shell variables `gen_files' and `gen_config' to the list of
1655 file names to output.
1656 * AC_DECLARE_YYTEXT does an AC_SUBST of `LEX_OUTPUT_ROOT', which may be
1657 "lex.yy" or "lexyy", depending on the system.
1658 * AC_PROGRAMS_CHECK takes an optional third arg. If given, it is used as
1660 * If AC_ALLOCA chooses alloca.c, it also defines STACK_DIRECTION.
1661 * AC_CONST works much more reliably on more systems.
1664 Major changes in Autoconf 1.3:
1666 configure no longer requires awk for packages that use a config.h.
1667 Support handling --with-PACKAGE options.
1668 New `autoheader' script to create `config.h.in' from `configure.in'.
1669 Ignore troublesome -lucb and -lPW when searching for alloca.
1670 Rename --exec_prefix to --exec-prefix for GNU standards conformance.
1671 Improve detection of STDC library.
1672 Add AC_HAVE_LIBRARY to check for non-default libraries.
1673 Function checking should work with future GNU libc releases.
1675 Major changes in Autoconf 1.2:
1677 The --srcdir option is now usually unnecessary.
1678 Add a file containing sample comments describing CPP macros.
1679 A comment in config.status tells which host it was configured on.
1680 Substituted variable values can now contain commas.
1681 Fix bugs in various feature checks.
1683 Major changes in Autoconf 1.1:
1685 Added AC_STRCOLL macro.
1686 Made AC_GETLOADAVG check for more things.
1687 AC_OUTPUT argument is now optional.
1692 Copyright (C) 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002,
1693 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
1695 This program is free software: you can redistribute it and/or modify
1696 it under the terms of the GNU General Public License as published by
1697 the Free Software Foundation, either version 3 of the License, or
1698 (at your option) any later version.
1700 This program is distributed in the hope that it will be useful,
1701 but WITHOUT ANY WARRANTY; without even the implied warranty of
1702 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1703 GNU General Public License for more details.
1705 You should have received a copy of the GNU General Public License
1706 along with this program. If not, see <http://www.gnu.org/licenses/>.