1 GNU Autoconf NEWS - User visible changes.
3 * Major changes in Autoconf 2.62a (2008-??-??)
5 ** AC_PATH_X now includes /lib64 and /usr/lib64 in its list of default
8 ** Newly obsolete macros
9 The following macro has been marked obsolete, since current porting
10 targets can safely assume C89 semantics that signal handlers return
11 void. We have no current plans to remove the macro.
15 ** Clients of m4_expand, such as AS_HELP_STRING and AT_SETUP, can now
16 handle properly quoted but otherwise unbalanced parentheses (for
17 some macros, this fixes a regression in 2.62).
19 ** Two new quadrigraphs have been introduced: @{:@ for (, and @:}@ for ),
20 allowing the output of unbalanced parantheses in more contexts.
22 ** The following m4sugar macros are new:
25 ** The following m4sugar macros now accept multiple arguments, as is the
26 case with underlying m4:
27 m4_defn m4_popdef m4_undefine
29 ** AT_KEYWORDS once again performs expansion on its argument, such that
30 AT_KEYWORDS([m4_if([$1], [], [default])]) no longer complains about
31 the possibly unexpanded m4_if [regression introduced in 2.62].
33 ** Config header templates `#undef UNDEFINED /* comment */' do not lead to
34 nested comments any more; regression introduced in 2.62.
37 * Major changes in Autoconf 2.62 (2008-04-05) [stable]
38 Released by Eric Blake, based on git versions 2.61a.*.
40 ** Many optimizations have been applied to make overall execution faster.
42 ** Autotest now makes use of shell functions.
44 ** config.status now uses awk instead of sed also for config headers.
46 - As a side effect, AC_DEFINE and AC_DEFINE_UNQUOTED now handle multi-line
47 values, i.e., backslash-newline combinations are handled correctly.
48 Further, for config headers, the total size of values is not limited by
49 the POSIX length limit of text lines any more, only each single line.
51 ** New config variable `top_build_prefix'.
53 ** New Autoconf macros:
54 AC_AUTOCONF_VERSION AC_OPENMP AC_PATH_PROGS_FEATURE_CHECK
56 ** AC_C_BIGENDIAN now supports universal binaries a la Mac OS X.
58 ** AC_C_RESTRICT now prefers to #define 'restrict' to a variant spelling
59 like '__restrict' if the variant spelling is available, as this is
60 more likely to work when mixing C and C++ code.
62 ** AC_CHECK_ALIGNOF's type argument T is now documented better: it must
63 be a string of tokens such that "T y;" is a valid member declaration
66 ** AC_CHECK_SIZEOF now accepts objects as well as types: the general rule
67 is that sizeof (X) works, then AC_CHECK_SIZEOF (X) should work.
69 ** AC_CHECK_TYPE and AC_CHECK_TYPES now work on any C type-name; formerly,
70 they did not work for function types. In C++, they now work on any
71 type-id that can be the operand of sizeof; this is similar to C,
72 except it excludes anonymous struct and union types. Formerly,
73 some (but not all) C++ types involving anonymous struct and union
74 were accepted, though this was not documented.
76 ** AC_CONFIG_LINKS now prefers to link against files in the build tree
77 if found, and it works to link against a file of the same name in
78 the source tree, even if both trees coincide.
80 ** AC_INIT no longer alters $@; regression introduced in 2.60.
82 ** AC_USE_SYSTEM_EXTENSIONS now defines _ALL_SOURCE for Interix platforms.
84 ** AS_HELP_STRING no longer underquotes its first argument; it also handles
85 the case where the first argument contains single-quoted commas.
86 For example, "AS_HELP_STRING([-a, [--arg[=foo]]], [bar])" produces:
87 " -a, --arg[=foo] bar"
88 Additionally, the macro now takes two additional arguments,
89 indent-column and wrap-column; these should not normally be needed,
90 but can be used to fine-tune how the output text is wrapped.
92 ** AC_PROG_INSTALL now requires an install program that can install multiple
93 files into a target directory.
95 ** The command 'autoconf -' now correctly processes a file from stdin.
97 ** 'autoreconf -m' now honors $MAKE.
99 ** For all of the directory arguments for 'configure', such as '--prefix'
100 or '--bindir', trailing slashes are stripped. As an example, if
101 tab completion in the user's shell appends trailing slashes, the
102 command './configure --prefix=/usr/' will still result in an
103 expanded libdir value of /usr/lib, not /usr//lib.
105 ** `configure --help=recursive' now works in read-only trees and from
106 unconfigured build trees.
108 ** If precious variables differ only in whitespace, then the cache consistency
109 check warns instead of fails, and reuses the old value.
111 ** AT_BANNER is now documented.
113 ** AT_SETUP now handles macro expansions properly when calculating line
116 ** Autotest now determines $srcdir correctly.
118 ** Testsuites built by autotest now accept a -C/--directory=DIR option
119 to adjust the working directory prior to creating files.
121 ** Autoconf now requires GNU M4 1.4.5 or later. Earlier versions of M4 have
122 a bug in macro tracing that interferes with the interaction between
123 Autoconf and Automake. GNU M4 1.4.11 or later is recommended. The
124 configure search for a working M4 is improved.
126 ** For portability with the eventual M4 2.0, macros should no longer use
127 anything larger than $9 to refer to arguments.
129 ** Documentation for m4sugar is improved.
131 - The following macros were previously available as undocumented
132 interfaces; the macros are now documented as stable interfaces.
134 __oline__ m4_assert m4_bmatch m4_bpatsubsts m4_car m4_case
135 m4_cdr m4_default m4_divert_once m4_divert_pop m4_divert_push
136 m4_divert_text m4_do m4_errprintn m4_fatal m4_flatten
137 m4_ifndef m4_ifset m4_ifval m4_ifvaln m4_location
138 m4_n m4_shiftn m4_strip m4_warn
140 - The following macros were previously available as undocumented
141 interfaces, but had bug fixes or semantic changes as part of this
142 release. Packages that relied on the undocumented behavior
143 should be analyzed to make sure they will still work with the
144 new documented behavior.
146 m4_cmp m4_list_cmp m4_join m4_map m4_map_sep m4_sign
147 m4_text_box m4_text_wrap m4_version_compare
149 - The m4_wrap macro used to have unspecified order, but now
150 guarantees FIFO order. m4_wrap_lifo was added to guarantee LIFO
153 - Packages using the undocumented m4sugar macro m4_PACKAGE_VERSION
154 should consider using the new AC_AUTOCONF_VERSION instead.
156 - m4sugar macros that are not documented in the manual are still
157 deemed experimental, and should not be used outside of Autoconf.
159 ** The m4sugar macros m4_append and m4_append_uniq, first documented in
160 2.60, have been fixed to treat both the string and the separator
161 arguments consistently with regards to quoting. Prior to this fix,
162 m4_append_uniq could mistakenly duplicate entries if the expansion
163 of the separator resulted in a different string (for example, if it
164 contained quotes, a comma, or a macro name). However, it means
165 that programs previously using
166 m4_append([name], [string], [[, ]])
167 are now using a four-character separator instead of the intended
168 comma and space. If you need portability to earlier versions of
169 Autoconf, you can insert the following snippet after AC_INIT but
170 before any other macro expansions, to enforce the new semantics:
171 m4_pushdef([m4_append], [m4_define([$1],
172 m4_ifdef([$1], [m4_defn([$1])[$3]])[$2])])
173 Additionally, m4_append_uniq now takes optional parameters that can
174 be used to take action depending on whether anything was appended,
175 and warns if a non-empty separator occurs within the string being
176 appended, since that can lead to duplicates.
178 ** The following m4sugar macros are new:
179 m4_append_uniq_w m4_apply m4_combine m4_cond m4_count
180 m4_dquote_elt m4_echo m4_expand m4_ignore m4_make_list m4_max
181 m4_min m4_newline m4_shift2 m4_shift3 m4_unquote m4_wrap_lifo
183 ** Warnings are now generated by default when an installer invokes
184 'configure' with an unknown --enable-* or --with-* option.
185 These warnings can be disabled with the new AC_DISABLE_OPTION_CHECKING
186 macro, or by invoking 'configure' with --disable-option-checking.
188 ** Existing obsolete macros
189 The documentation for the following macros is adjusted to make it
190 more clear that they have previously been marked obsolete, as their
191 functionality can be accomplished by other macros. We have no
192 current plans to remove them from Autoconf.
194 AC_ENABLE AC_STRUCT_ST_BLKSIZE AC_STRUCT_ST_RDEV AC_WITH
196 ** Newly obsolete macros
197 The following macros have been marked obsolete, as they only
198 perform a subset of AC_USE_SYSTEM_EXTENSIONS. We have no current
199 plans to remove them.
201 AC_AIX AC_GNU_SOURCE AC_ISC_POSIX AC_MINIX
203 ** AC_C_LONG_DOUBLE is obsolescent.
204 The documentation now says that AC_C_LONG_DOUBLE is obsolescent: it
205 tests for problems that are so old that it is no longer of
206 practical importance on current systems. New programs need not use
207 AC_C_LONG_DOUBLE. We have no current plans to remove it.
209 ** AC_DIAGNOSE, AC_WARNING, and AC_FATAL are obsolescent.
210 The documentation now favors the use of M4sugar macros m4_warn and
211 m4_fatal, since the naming makes it more obvious that the
212 diagnostics are associated with M4 expansion (ie. when running
213 `autoconf'), and offers less confusion with the AC_MSG_ERROR,
214 AC_MSG_FAILURE, and AC_MSG_WARN macros which manage diagnostics
215 when running `configure'. We have no current plans to remove these
219 * Major changes in Autoconf 2.61a (2006-12-11)
221 ** AC_FUNC_FSEEKO was broken in 2.61; it didn't make fseeko and ftello visible
222 on many platforms. This has been fixed.
224 ** AC_FUNC_SETVBUF_REVERSED is now obsolete. It is still defined for backward
225 compatibility but it does nothing. The macro was already
226 obsolescent, as the last systems to have the problem were those
227 based on SVR2, which became obsolete in 1987. The macro had bugs
228 on some modern systems and could no longer be maintained reliably
229 due to lack of ancient systems to test it on.
231 ** config.status now uses awk instead of sed for most substitutions, for speed.
233 - As a side effect multi-line values of substituted variables no
234 longer have a small limit in total size, though for portability
235 each line should not exceed the POSIX length limit for text lines.
237 - It is now documented that Makefile.in should not contain
238 overlapping variable occurrences, e.g., @VAR1@VAR2@.
239 Autoconf's behavior was always iffy in such cases, and the
240 awk implementation has changed the behavior.
242 ** Many uses of 'echo' have been rewritten so that Autoconf-generated
243 scripts have fewer problems with strings or file names containing
244 embedded special characters such as backslash or leading "-". This
245 was implemented by using `printf '%s\n' "$foo"' instead of `echo
246 "$foo"' when printf works. Due to the implementation technique
247 used, Autoconf-generated scripts now run considerably more slowly
248 on ancient implementations lacking printf. However, this should
249 not be a problem, since Autoconf-generated scripts in practice
250 invariably find a more-modern shell these days.
253 * Major changes in Autoconf 2.61 (2006-11-17)
255 ** New macros AC_C_FLEXIBLE_ARRAY_MEMBER, AC_C_VARARRAYS.
257 ** AC_ARG_ENABLE and AC_ARG_WITH now allow '.' in feature and package names.
260 * Major changes in Autoconf 2.60b (2006-10-22)
263 Autoconf-generated shell scripts no longer export BIN_SH, due to
264 configuration hassles with this. Installers who need BIN_SH in
265 their environment should set it before invoking 'configure' and
266 'make'. As far as we know, this affects only Unixware installations.
268 ** Obsolescent macros
269 The documentation now says that the following macros are obsolescent,
270 as they are superseded by Gnulib:
272 AC_FUNC_FNMATCH AC_FUNC_FNMATCH_GNU AC_FUNC_GETLOADVG AC_REPLACE_FNMATCH
274 New programs should use the Gnulib counterparts of these macros.
275 We have no current plans to remove them from Autoconf.
277 ** AC_COMPUTE_INT no longer caches or reports results.
279 ** AC_CHECK_DECL now also works with aggregate objects.
281 ** AC_USE_SYSTEM_EXTENSIONS now defines _TANDEM_SOURCE for NonStop platforms.
283 ** GNU M4 1.4.7 or later is now recommended.
286 New M4sugar macro, which is more secure than the POSIX M4 maketemp.
289 Now an alias for m4_mkstemp.
291 * Major changes in Autoconf 2.60a (2006-08-25)
293 ** GNU M4 1.4.6 or later is now recommended.
295 ** The check for C99 now tests for varargs macros, as documented.
296 It also tests that the preprocessor supports 64-bit integers.
298 ** Autoconf now uses constructs like "#ifdef HAVE_STDLIB_H" rather than
299 "#if HAVE_STDLIB_H", so that it now works with "gcc -Wundef -Werror".
301 ** The functionality of the undocumented _AC_COMPUTE_INT is now provided
302 by a public and documented macro, AC_COMPUTE_INT. The parameters to the
303 two macros are different, so autoupdate will not change the old private name
304 to the new one. _AC_COMPUTE_INT may be removed in a future release.
306 ** AC_TYPE_LONG_LONG_INT and AC_TYPE_UNSIGNED_LONG_LONG_INT now require
307 that long long types be at least 64 bits wide, as C99 and tradition
308 requires. Formerly, they accepted implementations of any width.
311 * Major changes in Autoconf 2.60
313 Released 2006-06-23, by Ralf Wildenhues.
315 ** Autoconf no longer depends on whether m4wrap is FIFO (as Posix requires)
316 or LIFO (as in GNU M4 1.4.x). GNU M4 2.0 is expected to conform to Posix
317 here, so m4wrap/m4_wrap users should no longer depend on LIFO behavior.
319 ** Provide a way to turn off warnings about the changed directory variables.
321 * Major changes in Autoconf 2.59d
323 Released 2006-06-05, by Ralf Wildenhues.
325 ** GNU make now recommended for VPATH builds
326 INSTALL now suggests VPATH builds (e.g., "sh ../srcdir/configure")
327 only if you use GNU make. In practice, other 'make' implementations
328 have too many subtle incompatibilities in their support for VPATH.
329 Many packages (including Autoconf itself) are portable to other
330 'make' implementations, but some packages are not, and recommending
331 GNU make keeps the installation instructions simpler.
333 ** Even more safety checks for the new Directory variables:
334 Warn about suspicious `${datarootdir}' found in config files output.
336 ** AC_TRY_COMMAND, AC_TRY_EVAL, ac_config_guess, ac_config_sub, ac_configure
337 These never-documented macros and variables have been marked with
338 comments saying that they may be removed in a future release,
339 because their use can lead to unintended code being executed.
340 If you need functionality that only these macros or variables
341 currently supply, please write bug-autoconf@gnu.org.
343 ** AC_SUBST, AC_DEFINE
344 Literal arguments to these are passed to m4_pattern_allow now.
347 Passing 'ac_cv_prog_cc_stdc=no' to 'configure' now sets ac_cv_prog_cc_c99
348 and ac_cv_prog_cc_c89 to 'no' as well, for backward compatibility with
349 obsolete K&R tests in the Automake test suite.
358 Now more robust with special characters in file names, or when
359 multiple processes create the same directory at the same time.
361 ** Obsolescent macros
362 The documentation now says that the following macros are obsolescent:
363 they test for problems that are so old that they are no longer of
364 practical importance on current systems.
366 AC_C_BACKSLASH_A AC_FUNC_MEMCMP AC_HEADER_DIRENT
367 AC_C_CONST AC_FUNC_SELECT_ARGTYPES AC_HEADER_STAT
368 AC_C_PROTOTYPES AC_FUNC_SETPGRP AC_HEADER_STDC
369 AC_C_STRINGIZE AC_FUNC_SETVBUF_REVERSED AC_HEADER_SYS_WAIT
370 AC_C_VOLATILE AC_FUNC_STAT AC_HEADER_TIME
371 AC_FUNC_CLOSEDIR_VOID AC_FUNC_STRFTIME AC_ISC_POSIX
372 AC_FUNC_GETPGRP AC_FUNC_UTIME_NULL AC_PROG_GCC_TRADITIONAL
373 AC_FUNC_LSTAT AC_FUNC_VPRINTF AC_STRUCT_TM
375 New programs need not use these macros. We have no current plans to
379 For compatibility with future Libtool 2.0, autoreconf will invoke
380 libtoolize with the option `--ltdl' now, if LT_CONFIG_LTDL_DIR is
383 * Major changes in Autoconf 2.59c
385 Released 2006-04-12, by Ralf Wildenhues.
387 ** The configure command now redirects standard input from /dev/null,
388 to help avoid problems with subsidiary commands that might mistakenly
389 read standard input. AS_ORIGINAL_STDIN_FD points to the original
390 standard input before this redirection, if you really want configure to
391 read from standard input.
393 ** Directory variables adjusted to recent changes in the GNU Coding Standards.
394 The following directory variables are new:
396 datarootdir read-only architecture-independent data root [PREFIX/share]
397 localedir locale-specific message catalogs [DATAROOTDIR/locale]
398 docdir documentation root [DATAROOTDIR/doc/PACKAGE]
399 htmldir html documentation [DOCDIR]
400 dvidir dvi documentation [DOCDIR]
401 pdfdir pdf documentation [DOCDIR]
402 psdir ps documentation [DOCDIR]
404 The following variables have new default values:
406 datadir read-only architecture-independent data [DATAROOTDIR]
407 infodir info documentation [DATAROOTDIR/info]
408 mandir man documentation [DATAROOTDIR/man]
410 This means that if you use any of `@datadir@', `@infodir@', or
411 `@mandir@' in a file, you will have to ensure `${datarootdir}' is
412 defined in this file. As a temporary measure, if any of those are
413 found but no mention of `datarootdir', the substitutions will be
414 replaced with values that do not contain `${datarootdir}', and a
415 warning will be issued.
417 ** @top_builddir@ is now a dir name: it is always nonempty and doesn't have
418 a trailing slash. Similar change will be made to ac_top_builddir in a
419 future release; the old style value, which matches (../)*, is (and will
420 continue to be) available as ac_top_build_prefix.
423 New macro to check for support of 'typeof' syntax a la GNU C.
425 ** AC_CHECK_DECLS_ONCE, AC_CHECK_FUNCS_ONCE, AC_CHECK_HEADERS_ONCE
426 New "once-only" variants of commonly-used macros, to make 'configure'
427 smaller and faster in common cases.
430 New macro to check for strtold with C99 semantics.
433 New macro that lets builder disable assertions at 'configure'-time.
436 Now checks for X11/Xlib.h and XrmInitialize (X proper) rather than
437 X11/Intrinsic.h and XtMalloc (Xt).
439 ** AC_PRESERVE_HELP_ORDER
440 New macro that causes `configure' to display help strings for AC_ARG_ENABLE
441 and AC_ARG_WITH arguments in one region, in the order defined. The default
442 behavior is to group options of each classes separately.
444 ** AC_PROG_CC, AC_PROG_CXX
445 No longer automatically arrange to declare the 'exit' function of C,
446 when a C++ compiler is used. Standard Autoconf macros no longer use
447 'exit', so this is no longer an issue for them. If you use C++, and
448 want to call 'exit', you'll have to arrange for its declaration
449 yourself. But we now suggest you return from 'main' instead.
451 ** AC_PROG_CC_C89, AC_PROG_CC_C99
452 New macros for ISO C99 support. AC_PROG_CC_C89 and AC_PROG_CC_C99
453 check for ANSI C89 and ISO C99 support respectively.
456 Has been unobsoleted, and will check if the compiler supports ISO
457 C99, falling back to ANSI C89 if not. ac_cv_prog_cc_stdc is
458 retained for backwards compatibility, assuming the value of
459 ac_cv_prog_cc_c99 or ac_cv_prog_cc_c89 (whichever is valid, in
462 ** AC_STRUCT_DIRENT_D_INO, AC_STRUCT_DIRENT_D_TYPE
463 New macros for checking commonly-used members of struct dirent.
466 The substituted value can now contain newlines.
469 The substitution now occurs only when @variable@ is on a line by itself,
470 optionally surrounded by spaces and tabs. The whole line is replaced.
472 ** AC_TYPE_LONG_DOUBLE, AC_TYPE_LONG_DOUBLE_WIDER
473 New macros to check for long double, and whether it is wider than double.
474 The old macro AC_C_TYPE_LONG_DOUBLE has been marked as obsolete;
475 applications should switch to the new macro.
477 ** AC_TYPE_INT8_T, AC_TYPE_INT16_T, AC_TYPE_INT32_T, AC_TYPE_INT64_T,
478 AC_TYPE_INTMAX_T, AC_TYPE_INTPTR_T, AC_TYPE_LONG_LONG_INT, AC_TYPE_SSIZE_T,
479 AC_TYPE_UINT8_T, AC_TYPE_UINT16_T, AC_TYPE_UINT32_T, AC_TYPE_UINT64_T,
480 AC_TYPE_UINTMAX_T, AC_TYPE_UINTPTR_T, AC_TYPE_UNSIGNED_LONG_LONG_INT
481 New macros to check for C99 and POSIX types.
483 ** AC_USE_SYSTEM_EXTENSIONS
484 New macro to enable extensions to Posix.
487 New macro which is defined to the name of the first declared config header
488 or undefined if no config headers have been declared yet.
491 The macro correctly handles quadrigraphs now.
493 ** AS_BOURNE_COMPATIBLE, AS_SHELL_SANITIZE, AS_CASE
494 These macros are new or published now.
497 New macro for copyright notices in testsuite files.
499 ** ALLOCA, LIBOBJS, LTLIBOBJS
500 Object names added to these variables are now prefixed with `${LIBOBJDIR}',
501 as in `${LIBOBJDIR}alloca.o'. LIBOBJDIR is meant to be defined from
502 `Makefile.in' in case the object files lie in a different directory.
503 The LIBOBJDIR feature is experimental.
506 Supports --no-recursive now.
508 ** New macros to support Erlang/OTP.
509 New macros for configuring paths to Erlang tools and libraries:
510 AC_ERLANG_PATH_ERLC, AC_ERLANG_NEED_ERLC, AC_ERLANG_PATH_ERL,
511 AC_ERLANG_NEED_ERL, AC_ERLANG_CHECK_LIB, AC_ERLANG_SUBST_ROOT_DIR,
512 AC_ERLANG_SUBST_LIB_DIR.
514 New macros for configuring installation of Erlang libraries:
515 AC_ERLANG_SUBST_INSTALL_LIB_DIR, AC_ERLANG_SUBST_INSTALL_LIB_SUBDIR.
517 ** The manual now mentions Gnulib more prominently.
519 ** New macros to support Objective C.
520 AC_PROG_OBJC, AC_PROG_OBJCPP.
522 * Major changes in Autoconf 2.59b
524 Released 2004-08-20, by Paul Eggert.
527 New macro that computes the default alignment of a type.
529 ** AC_CHECK_TOOL, AC_PATH_TOOL, AC_CHECK_TOOLS
530 When cross-compiling, these macros will give a warning if the tool
531 is not prefixed. In the future, unprefixed cross tools will not
532 be detected; please consult the info documentation for information
533 about the reason of this change.
535 ** AC_CHECK_TARGET_TOOL, AC_PATH_TARGET_TOOL, AC_CHECK_TARGET_TOOLS
536 New macros that detect programs whose name is prefixed with the
537 target type, if the build type and target type are different.
539 ** AC_REQUIRE_AUX_FILE
540 New trace macro that declares expected auxiliary files.
543 New macro that tests for a grep program that accepts as a long a line
546 ** AC_PROG_EGREP, AC_PROG_FGREP
547 These macros now require AC_PROG_GREP, and try EGREP="$GREP -E" and
548 FGREP="$GREP -F" respectively if possible, or else run a path search for
549 a program that accepts as long a line as possible.
552 New macro that tests for a sed program that truncates as few characters
555 * Major changes in Autoconf 2.59
557 Released 2003-11-04, by Akim Demaille
559 ** ac_abs_builddir etc.
560 Absolute file names were actually relative in 2.58.
562 * Major changes in Autoconf 2.58
564 Released 2003-11-04, by Akim Demaille
567 core.* files are no longer removed, as they may be valid user files.
569 ** autoreconf and auxiliary directory
570 Autoreconf creates the auxiliary directory if needed. This is
571 especially useful for initial "bootstrapping" of fresh CVS checkouts.
573 ** AC_CONFIG_MACRO_DIR
574 Use this macro to declare the directory for local M4 macros for aclocal.
577 No longer includes twice the same file in LIBOBJS if invoked
580 ** AC_CONFIG_COMMANDS
581 The directory for its first argument is automatically created. For
584 AC_CONFIG_COMMANDS([src/modules.hh], [...])
586 $top_builddir/src/ is created if needed.
588 ** Autotest and local.at
589 The optional file local.at is always included in Autotest test suites.
592 The warnings are always issued, including with cached runs.
593 This became a significant problem since aclocal and automake can
594 run autoconf behind the scene.
596 ** autoheader warnings
597 The warnings of autoheader can be turned off, using --warning.
598 For instance, -Wno-obsolete disables the complaints about acconfig.h
599 and other deprecated constructs.
602 AC_C_RESTRICT, AC_INCLUDES_DEFAULT, AC_LANG_ASSERT, AC_LANG_WERROR,
605 ** AC_DECL_SYS_SIGLIST
609 Now checks that mktime is the inverse of localtime.
611 ** Improve DJGPP portability
612 The Autoconf tools and configure behave better under DJGPP.
614 ** Present But Cannot Be Compiled
615 New FAQ section dedicated to the mystic
617 configure: WARNING: pi.h: present but cannot be compiled
618 configure: WARNING: pi.h: check for missing prerequisite headers?
619 configure: WARNING: pi.h: proceeding with the preprocessor's result
622 ** Concurrent executions of autom4te
623 autom4te now locks its internal files, which enables concurrent
624 executions of autom4te, likely to happen if automake, autoconf,
625 autoheader etc. are run simultaneously.
628 Use of Libtool 1.5 and higher is encouraged. Compatibility with
629 Libtool pre-1.4 is not checked.
632 Testsuites no longer rerun failed tests in verbose mode; instead,
633 failures are logged while the test is run.
635 In addition, expected failures can be marked as such.
637 * Major changes in Autoconf 2.57
639 Released 2002-12-03 by Paul Eggert.
641 Bug fixes for problems with AIX linker, with freestanding C compilers,
642 with GNU M4 limitations, and with obsolete copies of GNU documents.
644 The Free Documentation License has been upgraded from 1.1 to 1.2.
646 * Major changes in Autoconf 2.56
648 Released 2002-11-15 by Akim Demaille.
650 One packaging problem fixed (config/install-sh was not executable).
652 * Major changes in Autoconf 2.55
654 Released 2002-11-14 by Akim Demaille.
658 Have your configure.ac checked by autoscan ("autoscan").
659 Try the warning options ("autoreconf -fv -Wall").
663 - AC_CHECK_HEADER, AC_CHECK_HEADERS
664 More information on proper use.
666 - Writing Test Programs
668 This sections explains how to write good test sources to use with
669 AC_COMPILE_IFELSE etc. It documents AC_LANG_PROGRAM and so forth.
671 - AC_FOO_IFELSE vs. AC_TRY_FOO
673 Explains why Autoconf moves from AC_TRY_COMPILE etc. to
674 AC_COMPILE_IFELSE and AC_LANG_PROGRAM etc.
678 - Is more robust to different Gettext installations.
680 - Produces messages (when --verbose) to be understood by Emacs'
683 - Supports -W/--warnings.
686 Once the GNU Build System reinstalled, run `./config.status
687 --recheck && ./config.status && make' if possible.
691 - Supports --cache, and --no-cache.
693 - ~/.autom4te.cfg makes it possible to disable the caching mechanism
694 (autom4te.cache). See `Customizing autom4te' in the documentation.
701 Support for the obsoleted options -m, --macrodir, -l, --localdir is
702 dropped in favor of the safer --include/--prepend-include scheme.
707 AC_COMPILER_IFELSE, AC_FUNC_MBRTOWC, AC_HEADER_STDBOOL,
708 AC_LANG_CONFTEST, AC_LANG_SOURCE, AC_LANG_PROGRAM, AC_LANG_CALL,
709 AC_LANG_FUNC_TRY_LINK, AC_MSG_FAILURE, AC_PREPROC_IFELSE.
712 Obsoleted macros are kept for Autoconf backward compatibility, but
713 should be avoided in configure.ac. Running autoupdate is advised.
716 - AC_DEFINE/AC_DEFINE_UNQUOTED
718 We have to stop using the old compatibility scheme --that tried to
719 avoid useless backslashes-- because Libtool 1.4.3 contains a
721 AC_DEFINE([error_t], [int],
722 [Define to a type to use for \`error_t' if it is not
723 otherwise available.])
725 We have to quote the single quotes and backslashes with \. The old
726 compatibility scheme saw that ` was backslashed, and therefore did
727 not quote the single quote... Failure. Hence, Autoconf 2.54 is not
728 compatible with Libtool. Autoconf 2.55 is, but in some cases might
729 produce more \ than wanted.
731 Please, note that in the future the same problem will happen with
732 AC_MSG_*: use `autoreconf -f -Wall'.
736 - Portability of the Autoconf package to Solaris.
738 - Spurious warnings caused by config.status.
739 This bug is benign, but painful: on some systems (typically
740 FreeBSD), warnings such as:
742 config.status: creating Makefile
743 mv: Makefile: set owner/group (was: 1357/0): Operation not permitted
745 could be issued. This is fixed.
748 Simultaneous executions of config.status are possible again.
750 - Precious variables accumulation
752 config.status could stack several copies of the precious variables
756 ** Plans for later versions
760 The compatibility hooks with the old scheme will be completely
761 removed. Please, advice/use `--build', `--host', and `--target'
764 - AC_CHECK_HEADER, AC_CHECK_HEADERS
766 The tests will be stricter, please make sure your invocations are
771 Shell functions will gradually be introduced, probably starting with
772 Autotest. If you know machines which are in use that you suspect
773 *not* to support shell functions, please run the test suite of
774 Autoconf 2.55 on it, and report the results to
775 bug-autoconf@gnu.org.
779 Special characters in AC_MSG_* need not be quoted. Currently,
780 Autoconf has heuristics to decide when a string is escaped, or has
781 to be escaped. This scheme is fragile, and will be removed; the
782 only risk is uglified messages. Please, run `autoreconf -f -Wall'
783 to find occurrences that will be affected.
785 * Major changes in Autoconf 2.54
787 Released 2002-09-13 by Akim Demaille.
791 - autoreconf no longer changes the version of the gettext/po/intl
792 support files. It now adds the files the correspond to the
793 AM_GNU_GETTEXT_VERSION declared in configure.ac.
795 Warning: It now relies on the 'autopoint' program, which is part
796 of GNU gettext 0.11.4 and newer.
798 Please note that you need to have a GNU gettext version that
799 corresponds at least to the AM_GNU_GETTEXT_VERSION declared
800 in configure.ac. You can upgrade to newer GNU gettext versions,
801 though, without needing to change configure.ac.
803 - The -I DIR or --include=DIR option now appends DIR to the include path
804 instead of prepending; this is for consistency with other GNU tools.
805 The new -B DIR or --prepend-include=DIR option has the old behavior.
810 Now handles all the gory details about LIBOBJS and LTLIBOBJS.
811 Please, remove lines such as
813 # This is necessary so that .o files in LIBOBJS are also
814 # built via the ANSI2KNR-filtering rules.
815 LIBOBJS=`echo $LIBOBJS|sed 's/\.o /\$U.o /g;s/\.o$/\$U.o/'`
817 and read the `AC_LIBOBJ vs LIBOBJS' section. Do not define U in
818 your Makefiles either.
820 - AC_CONFIG_LINKS now makes copies if it can't make links.
822 - AC_FUNC_FNMATCH now tests only for POSIX compatibility, reverting to
823 Autoconf 2.13 behavior. The new macro AC_FUNC_FNMATCH_GNU also
824 tests for GNU extensions to fnmatch, and replaces fnmatch if needed.
826 - AC_FUNC_SETVBUF_REVERSED no longer fails when cross-compiling.
828 - AC_PROG_CC_STDC is integrated into AC_PROG_CC.
830 - AC_PROG_F77 default search no longer includes cf77 and cfg77.
834 AC_C_BACKSLASH_A, AC_CONFIG_LIBOBJ_DIR, AC_GNU_SOURCE,
835 AC_PROG_EGREP, AC_PROG_FGREP, AC_REPLACE_FNMATCH,
836 AC_FUNC_FNMATCH_GNU, AC_FUNC_REALLOC, AC_TYPE_MBSTATE_T.
839 looks for getloadavg.c in the CONFIG_LIBOBJ_DIR.
842 Now defines HAVE_MALLOC to 0 if `malloc' does not work, and asks
843 for an AC_LIBOBJ replacement.
847 - Spurious complaints from `m4_bmatch' about invalid regular
848 expressions are suppressed.
850 - Empty top_builddirs are properly handled.
852 - AC_CHECK_MEMBER works correctly when the member is an aggregate.
855 Now colon in the optional path arguments are properly handled.
857 ** Improved portability
859 - Both Autoconf the package, and the scripts it produces, should run
860 more reliably with Zsh. Bear in mind it is the default Bourne shell
863 - Autoconf and the scripts it produces no longer assume the existence of
864 the obsolescent commands egrep and fgrep.
868 - Limitations of Make
872 The GNATS base moved to
873 http://bugs.gnu.org/cgi-bin/gnatsweb.pl?database=autoconf
874 (It is no longer available, though.)
879 Now contains the list of ouput variables and files (AC_SUBST,
882 * Major changes in Autoconf 2.53
884 Released 2002-03-08 by Akim Demaille.
888 Perl 5.005_03 or later is required: autom4te is written in Perl and is
889 needed by autoconf. autoheader, autoreconf, ifnames, and autoscan are
895 Argument requirements, output variables, defined macros.
896 - M4sugar, M4sh, Autotest
898 - Double quoting macros
899 AC_TRY_CPP, AC_TRY_COMPILE, AC_TRY_LINK and AC_TRY_RUN.
901 The Autoconf manual is now distributed under the terms of the GNU FDL.
902 - Section `Hosts and Cross-Compilation'
903 Explains the rationale for the 2.5x changes in the cross-compilation
904 chain, and in the relationships between build, host, and target
906 Emphasizes that `cross-compilation' == `--host is given'.
907 If you are working on compilers etc., be sure to read this section.
908 - Section `AC_LIBOBJ vs. LIBOBJS'
909 Explains why assigning LIBOBJS directly is now an error.
910 Details how to update the code.
915 Now used instead of hard coded line numbers.
916 This eases the comparison of `configure's, and diminishes the
917 pressure over control version archives.
918 Automatic replacement for shells that don't support this feature.
919 - New output variables
920 @builddir@, @top_builddir@, @abs_srcdir@, @abs_top_srcdir@, @abs_builddir@,
925 Autoconf and Autotest modes are provided.
930 New, used by the Autoconf suite to cache and speed up most processing.
932 Supported by autom4te, autoconf and autoheader.
934 Replaces --autoconf-dir and --localdir in autoconf, autoheader,
935 autoupdate, and autoreconf.
937 No longer passes --cygnus, --foreign, --gnits, --gnu, --include-deps:
938 automake options are to be given via AUTOMAKE_OPTIONS.
940 Runs gettextize and libtoolize when appropriate.
942 --m4dir is no longer supported.
944 Now runs only in the specified directories, defaulting to `.',
945 but understands AC_CONFIG_SUBDIRS for dependent directories.
946 Before, it used to run on all the `configure.ac' found in the
948 Independent packages are properly updated.
952 - The top level $prefix is propagated to the AC_CONFIG_SUBDIRS configures.
954 Under the user pressure, $? is finally available. Probably a mistake.
955 - AC_F77_LIBRARY_LDFLAGS now supports the HP/UX f90 compiler.
956 - Precious variables accumulation
957 config.status could stack several copies of the precious variables
959 - AC_PATH_PROG and family.
960 Works properly when given a literal path.
962 Somewhere since 2.13, the result had been reversed.
966 - AC_C_BIGENDIAN supports the cross-compiling case.
967 - AC_C_BIGENDIAN accepts ACTION-IF-TRUE, ACTION-IF-FALSE, and
968 ACTION-IF-UNKNOWN arguments. All are facultative, and the default
969 for ACTION-IF-TRUE is to define WORDS_BIGENDIAN like AC_C_BIGENDIAN
971 - AC_C_LONG_DOUBLE now succeeds only if `long double' has more range or
972 precision than `double'.
977 It now defines the preprocessor symbols PACKAGE_NAME,
978 PACKAGE_TARNAME, PACKAGE_VERSION, PACKAGE_STRING, and
982 Admits a fourth optional parameter: the tar name.
984 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS.
985 Provide the user with srcdir, ac_srcdir, ac_top_srcdir, ac_builddir,
986 ac_top_builddir, ac_abs_srcdir, ac_abs_top_srcdir, ac_abs_builddir,
989 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS and AC_OUTPUT.
990 Are much less expensive when using long lists of files.
993 Works with shell variables, and non alphanumeric names.
997 - AC_FUNC_STRERROR_R now sets STRERROR_R_CHAR_P, not HAVE_WORKING_STRERROR_R,
998 because POSIX 1003.1-200x draft 7 says strerror_r returns int, not char *.
1000 - AC_FUNC_STRTOD substitutes POW_LIB.
1005 * Major changes in Autoconf 2.52
1007 Released 2001-07-18 by Akim Demaille.
1012 This feature was present in autoconf 2.50 but was not documented.
1013 For example, `@<:@' is translated to `[' just before output. This
1014 is useful when writing strings that contain unbalanced quotes, or
1015 other hard-to-quote constructs.
1016 - m4_pattern_forbid, m4_pattern_allow
1017 - Tips for upgrading from 2.13.
1018 - Using autoscan to maintain a configure.ac.
1021 - Now include stdint.h.
1022 - sys/types.h and sys/stat.h are guarded.
1023 - strings.h is included if available, and not conflicting with string.h.
1026 - The test suite is more robust and presents less false failures.
1027 - Invocation of GNU M4 now robust to POSIXLY_CORRECT.
1028 - configure accepts --prefix='' again.
1029 - AC_CHECK_LIB works properly when its first argument is not a
1031 - HAVE_INTTYPES_H is defined only if not conflicting with sys/types.h.
1032 - build_, host_, and target_alias are AC_SUBST as in 2.13.
1033 - AC_ARG_VAR properly propagates precious variables inherited from the
1034 environment to ./config.status.
1035 - Using --program-suffix/--program-prefix is portable.
1036 - Failures to detect the default compiler's output extension are less
1038 - `config.status foo' works properly when `foo' depends on variables
1039 set in an AC_CONFIG_THING INIT-CMD.
1040 - autoheader is more robust to broken input.
1041 - Fixed Fortran name-mangling and link tests on a number of systems,
1042 e.g. NetBSD; see AC_F77_DUMMY_MAIN, below.
1045 - AC_CHECK_HEADER and AC_CHECK_HEADERS support a fourth argument to
1046 specify pre-includes. In this case, the headers are compiled with
1047 cc, not merely preprocessed by cpp. Therefore it is the _usability_
1048 of a header which is checked for, not just its availability.
1049 - AC_ARG_VAR refuses to run configure when precious variables have
1051 - Versions of compilers are dumped in the logs.
1052 - AC_CHECK_TYPE recognizes use of `foo_t' as a replacement type.
1055 - AC_PATH_XTRA only adds -ldnet to $LIBS if it's needed to link.
1056 - AC_FUNC_WAIT3 and AC_SYS_RESTARTABLE_SYSCALLS are obsoleted.
1057 - AM_FUNC_ERROR_AT_LINE, AM_FUNC_FNMATCH, AM_FUNC_MKTIME,
1058 AM_FUNC_OBSTACK, and AM_FUNC_STRTOD are now activated.
1059 Be sure to read `Upgrading from Version 2.13' to understand why
1060 running `autoupdate' is needed.
1061 - AC_F77_DUMMY_MAIN, AC_F77_MAIN: new macros to detect whether
1062 a main-like routine is required/possible when linking C/C++ with
1063 Fortran. Users of e.g. AC_F77_WRAPPERS should be aware of these.
1064 - AC_FUNC_GETPGRG behaves better when cross-compiling.
1066 * Major changes in Autoconf 2.51
1067 There was no release of Autoconf 2.51 since some packagers had used
1068 this version number without permission to ship intermediary versions
1069 of 2.50. The version was skipped to avoid confusion.
1071 * Major changes in Autoconf 2.50
1073 Released 2001-05-21 by Akim Demaille.
1075 ** Lots of bug fixes
1076 There have been far too many to enumerate them here. Check out
1077 ChangeLog if you really want to know more.
1079 ** Improved documentation
1080 In particular, portability issues are better covered.
1083 All the standard GNU Makefile targets are supported. The layout has
1084 changed: m4/ holds the M4 extensions Autoconf needs for its
1085 configuration, doc/ contains the documentation, and tests/ contains
1088 ** Man pages are provided
1089 For autoconf, autoreconf, autoupdate, autoheader, autoscan, ifnames,
1090 config.guess, config.sub.
1094 Provides a safe and powerful means to trace the macro uses. This
1095 provide the parsing layer for tools which need to `study'
1099 Specify what category of warnings should be enabled.
1101 - When recursing into subdirectories, try for configure.gnu before
1102 configure to adapt for packages not using autoconf on case-insensitive
1106 More errors are now caught (circular AC_REQUIRE dependencies,
1107 AC_DEFINE in the action part of an AC_CACHE_CHECK, too many pops
1108 etc.). In addition, their location and call stack are given.
1111 autoupdate is much more powerful, and is able to provide the glue code
1112 which might be needed to move from an old macro to its newer
1115 You are strongly encouraged to use it to modernize both your
1116 `configure.in' and your .m4 extension files.
1119 The internal machinery of autoheader has completely changed. As a
1120 result, using `acconfig.h' should be considered to be obsoleted, and
1121 you are encouraged to get rid of it using the AH macros.
1126 ** Fortran 77 compilers
1127 Globally, the support for Fortran 77 is considerably improved.
1129 Support for automatically determining a Fortran 77 compiler's
1130 name-mangling scheme. New CPP macros F77_FUNC and F77_FUNC_ are
1131 provided to wrap C/C++ identifiers, thus making it easier and more
1132 transparent for C/C++ to call Fortran 77 routines, and Fortran 77 to
1133 call C/C++ routines. See the Texinfo documentation for details.
1136 The test suite no longer uses DejaGNU. It should be easy to submit
1137 test cases in this new framework.
1140 - --help, --help=long, -hl
1141 no longer dumps useless items.
1143 lists only specific options.
1144 - --help=recursive, -hr
1145 displays the help of all the embedded packages.
1146 - Remembers environment variables when reconfiguring.
1147 The previous scheme to set envvar before running configure was
1149 what prevented configure from remembering the environment in which
1150 it was run, therefore --recheck was run in an inconsistent
1151 environment. Now, one should run
1153 and then --recheck will work properly. Variables declared with
1154 AC_ARG_VAR are also preserved.
1156 $build defaults to `config.guess`, $host to $build, and then $target
1158 Cross-compilation is a global status of the package, it no longer
1159 depends upon the current language.
1160 Cross compilation is enabled iff the user specified `--host'.
1161 `configure' now fails if it can't run the executables it compiles,
1162 unless cross-compilation is enabled.
1164 The cache file is disabled by default. The new options
1165 `--config-cache', `-C' set the cache to `config.cache'.
1169 Much faster on most architectures.
1170 - concurrent executions
1171 It is safe to use `make -j' with config.status.
1172 - human interface improved
1173 It is possible to invoke
1174 ./config.status foobar
1175 instead of the former form (still valid)
1176 CONFIG_COMMANDS= CONFIG_HEADERS= CONFIG_LINKS= \
1177 CONFIG_FILES=foobar:foo.in:bar.in \
1179 The same holds for configuration headers and links.
1180 You can instantiate unknown files and headers:
1181 ./config.status --header foo.h:foo.h.in --file bar:baz
1182 - has a useful --help
1183 - accepts special file name "-" for stdin/stdout
1188 Specify additional copyright information.
1191 Now expects the identity of the package as argument.
1195 Most macros, if not all, now strictly follow the `one quotation
1196 level' rule. This results in a more predictable expansion.
1199 A sly bug in the AC_REQUIRE machinery, which could produce incorrect
1200 configure scripts, was fixed by Axel Thimm.
1204 Document and ask for the registration of an envvar.
1207 Specifies the file which `configure' should look for when trying to
1208 find the source tree (used to be handled by AC_INIT).
1210 - AC_CONFIG_COMMANDS
1211 To add new actions to config.status. Should be used instead of
1215 Replaces AC_LINK_FILES.
1217 - AC_CONFIG_HEADERS, AC_CONFIG_COMMANDS, AC_CONFIG_SUBDIRS,
1218 AC_CONFIG_LINKS, and AC_CONFIG_FILES
1219 They now obey sh: you should no longer use shell variables as
1220 argument. Instead of
1222 test "$package_foo_enabled" = yes && $my_subdirs="$my_subdirs foo"
1223 AC_CONFIG_SUBDIRS($my_subdirs)
1227 if test "$package_foo_enabled" = yes; then
1228 AC_CONFIG_SUBDIRS(foo)
1232 To format an Autoconf macro's help string so that it looks pretty
1233 when the user executes `configure --help'.
1236 ** Generic Test Macros
1238 The interface of the AC_CHECK families of macros (decl, header,
1239 type, member, func) is now uniform. They support the same set of
1242 - AC_CHECK_DECL, AC_CHECK_DECLS
1243 To check whether a symbol is declared.
1245 - AC_CHECK_SIZEOF, AC_C_CHAR_UNSIGNED.
1246 No longer need a cross-compilation default.
1249 The test it performs is much more robust than previously, and makes
1250 it possible to test builtin types in addition to typedefs.
1251 It is now schizophrenic:
1252 - AC_CHECK_TYPE(TYPE, REPLACEMENT)
1253 remains for backward compatibility, but its use is discouraged.
1254 - AC_CHECK_TYPE(TYPE, IF-FOUND, IF-NOT-FOUND, INCLUDES)
1255 behaves exactly like the other AC_CHECK macros.
1258 Checks whether given types are supported by the system.
1260 - AC_CHECK_MEMBER, AC_CHECK_MEMBERS
1261 Check for given members in aggregates (e.g., pw_gecos in struct
1265 Checks if the compiler supports ISO C, included when needs special
1269 Checking whether the preprocessor indicates missing includes by the
1270 error code. stderr is checked by AC_TRY_CPP only as a fallback.
1273 Takes a language as argument and replaces AC_LANG_C,
1274 AC_LANG_CPLUSPLUS and AC_LANG_FORTRAN77.
1276 - AC_LANG_PUSH, AC_LANG_POP
1277 Are preferred to AC_LANG_SAVE, AC_LANG_RESTORE.
1280 - AC_FUNC_CHOWN, AC_FUNC_MALLOC, AC_FUNC_STRERROR_R,
1281 AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK, AC_FUNC_STAT, AC_FUNC_LSTAT,
1282 AC_FUNC_ERROR_AT_LINE, AC_FUNC_OBSTACK, AC_FUNC_STRTOD, AC_FUNC_FSEEKO.
1286 Sets GETGROUPS_LIBS.
1288 - AC_FUNC_GETLOADAVG
1289 Defines `HAVE_STRUCT_NLIST_N_UN_N_NAME' instead of `NLIST_NAME_UNION'.
1292 Now integrates `AC_DECL_YYTEXT' which is obsoleted.
1295 Arrange for large-file support.
1297 - AC_EXEEXT, AC_OBJEXT
1298 You are no longer expected to use them: their computation is
1299 performed by default.
1301 ** C++ compatibility
1302 Every macro has been revisited in order to support at best CC=c++.
1304 Major changes in Autoconf 2.14:
1305 There was no release of GNU Autoconf 2.14.
1307 Major changes in Autoconf 2.13:
1309 Released 1999-05-01 by Ben Elliston.
1311 * Support for building on Win32 systems where the only available C or
1312 C++ compiler is the Microsoft Visual C++ command line compiler
1313 (`cl'). Additional support for building on Win32 systems which are
1314 using the Cygwin or Mingw32 environments.
1315 * Support for alternative object file and executable file extensions.
1316 On Win32, for example, these are .obj and .exe. These are discovered
1317 using AC_OBJEXT and AC_EXEEXT, which substitute @OBJEXT@ and
1318 @EXEEXT@ in the output, respectively.
1319 * New macros: AC_CACHE_LOAD, AC_CACHE_SAVE, AC_FUNC_SELECT_ARGTYPES,
1320 AC_VALIDATE_CACHED_SYSTEM_TUPLE, AC_SEARCH_LIBS, AC_TRY_LINK_FUNC,
1321 AC_C_STRINGIZE, AC_CHECK_FILE(S), AC_PROG_F77 (and friends).
1322 * AC_DEFINE now has an optional third argument for a description to be
1323 placed in the config header input file (e.g. config.h.in).
1324 * The C++ code fragment compiled for the C++ compiler test had to be
1325 improved to include an explicit return type for main(). This was
1326 causing failures on systems using recent versions of the EGCS C++
1328 * Fixed an important bug in AC_CHECK_TYPE that would cause a configure
1329 script to report that `sometype_t' was present when only `type_t'
1331 * Merge of the FSF version of config.guess and config.sub to modernize
1332 these scripts. Add support for a few new hosts in config.guess.
1333 Incorporate latest versions of install-sh, mkinstalldirs and
1334 texinfo.tex from the FSF.
1335 * autoreconf is capable of running automake if necessary (and
1337 * Support for Fortran 77. See the Texinfo documentation for details.
1338 * Bug fixes and workarounds for quirky bugs in vendor utilities.
1340 Major changes in Autoconf 2.12:
1342 Released 1996-11-26 by David J. MacKenzie
1344 * AC_OUTPUT and AC_CONFIG_HEADER can create output files by
1345 concatenating multiple input files separated by colons, like so:
1346 AC_CONFIG_HEADER(config.h:conf.pre:config.h.in:conf.post)
1347 AC_OUTPUT(Makefile:Makefile.in:Makefile.rules)
1348 The arguments may be shell variables, to compute the lists on the fly.
1349 * AC_LINK_FILES and AC_CONFIG_SUBDIRS may be called multiple times.
1350 * New macro AC_OUTPUT_COMMANDS adds more commands to run in config.status.
1353 Major changes in Autoconf 2.11:
1355 Released November 18th, 1996, by David J. MacKenzie
1357 * AC_PROG_CC and AC_PROG_CXX check whether the compiler works.
1358 They also default CFLAGS/CXXFLAGS to "-g -O2" for gcc, instead of "-g -O".
1359 * AC_REPLACE_FUNCS defines HAVE_foo if the system has the function `foo'.
1360 * AC_CONFIG_HEADER expands shell variables in its argument.
1361 * New macros: AC_FUNC_FNMATCH, AC_FUNC_SETPGRP.
1362 * The "checking..." messages and the source code for test programs that
1363 fail are saved in config.log.
1364 * Another workaround has been added for seds with small command length limits.
1365 * config.sub and config.guess recognize more system types.
1368 Major changes in Autoconf 2.10:
1370 Released May 7th, 1996, by Roland McGrath
1373 * The cache variable names used by `AC_CHECK_LIB(LIB, FUNC, ...)' has
1374 changed: now $ac_cv_lib_LIB_FUNC, previously $ac_cv_lib_LIB.
1376 Major changes in Autoconf 2.9:
1378 Released March 16th, 1996, by Roland McGrath
1382 Major changes in Autoconf 2.8:
1384 Released March 8th, 1996, by Roland McGrath
1388 Major changes in Autoconf 2.7:
1390 Released November 22nd, 1995, by David J. MacKenzie
1394 Major changes in Autoconf 2.6:
1396 Released November 20th, 1995, by David J. MacKenzie
1400 Major changes in Autoconf 2.5:
1402 Released November 17th, 1995, by Roland McGrath
1404 * New configure options --bindir, --libdir, --datadir, etc., with
1405 corresponding output variables.
1406 * New macro: AC_CACHE_CHECK, to make using the cache easier.
1407 * config.log contains the command being run as well as any output from it.
1408 * AC_CHECK_LIB can check for libraries with "." or "/" or "+" in their name.
1409 * AC_PROG_INSTALL doesn't cache a name for install-sh, for sharing caches.
1410 * AC_CHECK_PROG, AC_PATH_PROG, AC_CHECK_PROGS, AC_PATH_PROGS, and
1411 AC_CHECK_TOOL can search a path other than $PATH.
1412 * AC_CHECK_SIZEOF takes an optional size to use when cross-compiling.
1414 Major changes in Autoconf 2.4:
1416 Released June 14th, 1995, by David J. MacKenzie
1418 * Fix a few bugs found by Emacs testers.
1420 Major changes in Autoconf 2.3:
1422 Released March 27th, 1995, by David J. MacKenzie
1424 * Fix the cleanup trap in several ways.
1425 * Handle C compilers that are picky about option placement.
1426 * ifnames gets the version number from the right directory.
1428 Major changes in Autoconf 2.2:
1430 Released March 8th, 1995, by David J. MacKenzie
1432 * The ifnames utility is much faster but requires a "new awk" interpreter.
1433 * AC_CHECK_LIB and AC_HAVE_LIBRARY check and add the new
1434 library before existing libs, not after, in case it uses them.
1435 * New macros: AC_FUNC_GETPGRP, AC_CHECK_TOOL.
1436 * Lots of bug fixes.
1437 * Many additions to the TODO file :-)
1439 Major changes in Autoconf 2.1:
1441 Released November 4th, 1994, by David J. MacKenzie
1444 * More explanations in the manual.
1445 * Fix a spurious failure in the testsuite.
1446 * Clarify some warning messages.
1447 * autoreconf by default only rebuilds configure and config.h.in files
1448 that are older than any of their particular input files; there is a
1449 --force option to use after installing a new version of Autoconf.
1451 Thanks to everybody who's submitted changes and additions to Autoconf!
1452 I've incorporated many of them, and am still considering others for
1453 future releases -- but I didn't want to postpone this release indefinitely.
1455 Caution: don't indiscriminately rebuild configure scripts with
1456 Autoconf version 2. Some configure.in files need minor adjustments to
1457 work with it; the documentation has a chapter on upgrading. A few
1458 configure.in files, including those for GNU Emacs and the GNU C
1459 Library, need major changes because they relied on undocumented
1460 internals of version 1. Future releases of those packages will have
1461 updated configure.in files.
1463 It's best to use GNU M4 1.3 (or later) with Autoconf version 2.
1464 Autoconf now makes heavy use of M4 diversions, which were implemented
1465 inefficiently in GNU M4 releases before 1.3.
1467 Major changes in Autoconf 2.0:
1469 Released October 26th, 1994, by David J. MacKenzie
1471 ** New copyright terms:
1472 * There are no restrictions on distribution or use of configure scripts.
1475 * Autoconf manual is reorganized to make information easier to find
1476 and has several new indexes.
1477 * INSTALL is reorganized and clearer and is now made from Texinfo source.
1480 * autoscan to generate a preliminary configure.in for a package by
1481 scanning its source code for commonly used nonportable functions,
1482 programs, and header files.
1483 * ifnames to list the symbols used in #if and #ifdef directives in a
1485 * autoupdate to update a configure.in to use the version 2 macro names.
1486 * autoreconf to recursively remake configure and configuration header
1487 files in a source tree.
1489 ** Changed utilities:
1490 * autoheader can take pieces of acconfig.h to replace config.h.{top,bot}.
1491 * autoconf and autoheader can look for package-local definition files
1492 in an alternate directory.
1495 * AC_CACHE_VAL to share results of tests between configure runs.
1496 * AC_DEFUN to define macros, automatically AC_PROVIDE them, and ensure
1497 that macros invoked with AC_REQUIRE don't interrupt other macros.
1498 * AC_CONFIG_AUX_DIR, AC_CANONICAL_SYSTEM, AC_CANONICAL_HOST, AC_LINK_FILES to
1499 support deciding unguessable features based on the host and target types.
1500 * AC_CONFIG_SUBDIRS to recursively configure a source tree.
1501 * AC_ARG_PROGRAM to use the options --program-prefix,
1502 --program-suffix, and --program-transform-name to change the names
1503 of programs being installed.
1504 * AC_PREFIX_DEFAULT to change the default installation prefix.
1505 * AC_TRY_COMPILE to compile a test program without linking it.
1506 * AC_CHECK_TYPE to check whether sys/types.h or stdlib.h defines a given type.
1507 * AC_CHECK_LIB to check for a particular function and library.
1508 * AC_MSG_CHECKING and AC_MSG_RESULT to print test results, on a single line,
1509 whether or not the test succeeds. They obsolete AC_CHECKING and AC_VERBOSE.
1510 * AC_SUBST_FILE to insert one file into another.
1511 * AC_FUNC_MEMCMP to check whether memcmp is 8-bit clean.
1512 * AC_FUNC_STRFTIME to find strftime even if it's in -lintl.
1513 * AC_FUNC_GETMNTENT to find getmntent even if it's in -lsun or -lseq.
1514 * AC_HEADER_SYS_WAIT to check whether sys/wait.h is POSIX.1 compatible.
1517 * Many macros renamed systematically, but old names are accepted for
1518 backward compatibility.
1519 * AC_OUTPUT adds the "automatically generated" comment to
1520 non-Makefiles where it finds @configure_input@ in an input file, to
1521 support files with various comment syntaxes.
1522 * AC_OUTPUT does not replace "prefix" and "exec_prefix" in generated
1523 files when they are not enclosed in @ signs.
1524 * AC_OUTPUT allows the optional environment variable CONFIG_STATUS to
1525 override the file name "config.status".
1526 * AC_OUTPUT takes an optional argument for passing variables from
1527 configure to config.status.
1528 * AC_OUTPUT and AC_CONFIG_HEADER allow you to override the input-file names.
1529 * AC_OUTPUT automatically substitutes the values of CFLAGS, CXXFLAGS,
1530 CPPFLAGS, and LDFLAGS from the environment.
1531 * AC_PROG_CC and AC_PROG_CXX now set CFLAGS and CXXFLAGS, respectively.
1532 * AC_PROG_INSTALL looks for install-sh or install.sh in the directory
1533 specified by AC_CONFIG_AUXDIR, or srcdir or srcdir/.. or
1534 srcdir/../.. by default.
1535 * AC_DEFINE, AC_DEFINE_UNQUOTED, and AC_SUBST are more robust and smaller.
1536 * AC_DEFINE no longer prints anything, because of the new result reporting
1537 mechanism (AC_MSG_CHECKING and AC_MSG_RESULT).
1538 * AC_VERBOSE pays attention to --quiet/--silent, not --verbose.
1539 * AC_ARG_ENABLE and AC_ARG_WITH support whitespace in the arguments to
1540 --enable- and --with- options.
1541 * AC_CHECK_FUNCS and AC_CHECK_HEADERS take optional shell commands to
1542 execute on success or failure.
1543 * Checking for C functions in C++ works.
1546 * AC_REMOTE_TAPE and AC_RSH removed; too specific to tar and cpio, and
1547 better maintained with them.
1548 * AC_ARG_ARRAY removed because no one was likely using it.
1549 * AC_HAVE_POUNDBANG replaced with AC_SYS_INTERPRETER, which doesn't
1550 take arguments, for consistency with all of the other specific checks.
1553 * Comes with config.sub and config.guess, and uses them optionally.
1554 * Uses config.cache to cache test results. An alternate cache file
1555 can be selected with the --cache-file=FILE option.
1556 * Uses optional shell scripts $prefix/share/config.site and
1557 $prefix/etc/config.site to perform site or system specific initializations.
1558 * configure saves compiler output to ./config.log for debugging.
1559 * New files autoconf.m4 and autoheader.m4 load the other Autoconf macros.
1560 * acsite.m4 is the new name for the system-wide aclocal.m4.
1561 * Has a DejaGnu test suite.
1563 Major changes in Autoconf 1.11:
1565 * AC_PROG_INSTALL calls install.sh with the -c option.
1566 * AC_SET_MAKE cleans up after itself.
1567 * AC_OUTPUT sets prefix and exec_prefix if they weren't set already.
1568 * AC_OUTPUT prevents shells from looking in PATH for config.status.
1570 Plus a few other bug fixes.
1572 Major changes in Autoconf 1.10:
1574 * autoheader uses config.h.bot if present, analogous to config.h.top.
1575 * AC_PROG_INSTALL looks for install.sh in srcdir or srcdir/.. and
1577 * AC_PROG_CXX looks for cxx as a C++ compiler.
1579 Plus several bugs fixed.
1581 Major changes in Autoconf 1.9:
1583 * AC_YYTEXT_POINTER replaces AC_DECLARE_YYTEXT.
1584 * AC_SIZEOF_TYPE generates the cpp symbol name automatically,
1585 and autoheader generates entries for those names automatically.
1586 * AC_FIND_X gets the result from xmkmf correctly.
1587 * AC_FIND_X assumes no X if --without-x was given.
1588 * AC_FIND_XTRA adds libraries to the variable X_EXTRA_LIBS.
1589 * AC_PROG_INSTALL finds OSF/1 installbsd.
1591 Major changes in Autoconf 1.8:
1594 * New macros AC_LANG_C, AC_LANG_CPLUSPLUS, AC_LANG_SAVE, AC_LANG_RESTORE,
1595 AC_PROG_CXX, AC_PROG_CXXCPP, AC_REQUIRE_CPP
1596 for checking both C++ and C features in one configure script.
1597 * New macros AC_CHECKING, AC_VERBOSE, AC_WARN, AC_ERROR for printing messages.
1598 * New macros AC_FIND_XTRA, AC_MMAP, AC_SIZEOF_TYPE, AC_PREREQ,
1599 AC_SET_MAKE, AC_ENABLE.
1602 * AC_FIND_X looks for X in more places.
1603 * AC_PROG_INSTALL defaults to install.sh instead of cp, if it's in srcdir.
1604 install.sh is distributed with Autoconf.
1605 * AC_DECLARE_YYTEXT has been removed because it can't work, pending
1606 a rewrite of quoting in AC_DEFINE.
1607 * AC_OUTPUT adds its comments in C format when substituting in C files.
1608 * AC_COMPILE_CHECK protects its ECHO-TEXT argument with double quotes.
1610 ** New or changed command line options:
1611 * configure accepts --enable-FEATURE[=ARG] and --disable-FEATURE options.
1612 * configure accepts --without-PACKAGE, which sets withval=no.
1613 * configure accepts --x-includes=DIR and --x-libraries=DIR.
1614 * Giving --with-PACKAGE no argument sets withval=yes instead of withval=1.
1615 * configure accepts --help, --version, --silent/--quiet, --no-create options.
1616 * configure accepts and ignores most other Cygnus configure options, and
1617 warns about unknown options.
1618 * config.status accepts --help, --version options.
1620 ** File names and other changes:
1621 * Relative srcdir values are not made absolute.
1622 * The values of @prefix@ and @exec_prefix@ and @top_srcdir@ get substituted.
1623 * Autoconf library files are installed in ${datadir}/autoconf, not ${datadir}.
1624 * autoheader optionally copies config.h.top to the beginning of config.h.in.
1625 * The example Makefile dependencies for configure et al. work better.
1626 * Namespace cleanup: all shell variables used internally by Autoconf
1627 have names beginning with `ac_'.
1629 More big improvements are in process for future releases, but have not
1630 yet been (variously) finished, integrated, tested, or documented enough
1633 Major changes in Autoconf 1.7:
1635 * New macro AC_OBSOLETE.
1636 * Bugs in Makefile.in fixed.
1637 * AC_LONG_FILE_NAMES improved.
1639 Major changes in Autoconf 1.6:
1641 * New macro AC_LONG_64_BITS.
1642 * Multiple .h files can be created.
1643 * AC_FIND_X looks for X files directly if it doesn't find xmkmf.
1644 * AC_ALLOCA defines C_ALLOCA if using alloca.c.
1645 * --with-NAME can take a value, e.g., --with-targets=sun4,hp300bsd.
1646 * Unused --no-create option to configure removed.
1647 * autoheader doesn't change the timestamp of its output file if
1648 the file didn't change.
1649 * All macros that look for libraries now use AC_HAVE_LIBRARY.
1650 * config.status checks three optional environment variables to
1651 modify its behavior.
1652 * The usual bug fixes.
1654 Major changes in Autoconf 1.5:
1656 * New macros AC_FIND_X, AC_OFF_T, AC_STAT_MACROS_BROKEN, AC_REVISION.
1657 * autoconf and autoheader scripts have GNU standards conforming
1658 --version and --help options (they print their message and exit).
1661 Major changes in Autoconf 1.4:
1663 * New macros AC_HAVE_POUNDBANG, AC_TIME_WITH_SYS_TIME, AC_LONG_DOUBLE,
1664 AC_GETGROUPS_T, AC_DEFINE_UNQUOTED.
1665 * autoconf and autoheader use the M4 environment variable to determine the
1666 name of the M4 program to use.
1667 * The --macrodir option to autoconf and autoheader specifies the directory
1668 in which acspecific.m4, acgeneral.m4, etc. reside if not the default.
1669 * autoconf and autoheader can take `-' as their file names, which means to
1670 read stdin as input.
1671 * Resulting configure scripts can take a --verbose option which causes them
1672 to print the results of their tests.
1673 * AC_DEFINE quotes its second argument in such a way that spaces, magic
1674 shell characters, etc. will be preserved during various stages of
1675 expansion done by the shell. If you don't want this, use
1676 AC_DEFINE_UNQUOTED instead.
1677 * Much textual processing done with external calls to tr and sed have been
1678 internalized with builtin M4 `patsubst' and `translit' calls.
1679 * AC_OUTPUT doesn't hardwire the file names it outputs. Instead, you can
1680 set the shell variables `gen_files' and `gen_config' to the list of
1681 file names to output.
1682 * AC_DECLARE_YYTEXT does an AC_SUBST of `LEX_OUTPUT_ROOT', which may be
1683 "lex.yy" or "lexyy", depending on the system.
1684 * AC_PROGRAMS_CHECK takes an optional third arg. If given, it is used as
1686 * If AC_ALLOCA chooses alloca.c, it also defines STACK_DIRECTION.
1687 * AC_CONST works much more reliably on more systems.
1690 Major changes in Autoconf 1.3:
1692 configure no longer requires awk for packages that use a config.h.
1693 Support handling --with-PACKAGE options.
1694 New `autoheader' script to create `config.h.in' from `configure.in'.
1695 Ignore troublesome -lucb and -lPW when searching for alloca.
1696 Rename --exec_prefix to --exec-prefix for GNU standards conformance.
1697 Improve detection of STDC library.
1698 Add AC_HAVE_LIBRARY to check for non-default libraries.
1699 Function checking should work with future GNU libc releases.
1701 Major changes in Autoconf 1.2:
1703 The --srcdir option is now usually unnecessary.
1704 Add a file containing sample comments describing CPP macros.
1705 A comment in config.status tells which host it was configured on.
1706 Substituted variable values can now contain commas.
1707 Fix bugs in various feature checks.
1709 Major changes in Autoconf 1.1:
1711 Added AC_STRCOLL macro.
1712 Made AC_GETLOADAVG check for more things.
1713 AC_OUTPUT argument is now optional.
1718 Copyright (C) 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002,
1719 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
1721 This program is free software: you can redistribute it and/or modify
1722 it under the terms of the GNU General Public License as published by
1723 the Free Software Foundation, either version 3 of the License, or
1724 (at your option) any later version.
1726 This program is distributed in the hope that it will be useful,
1727 but WITHOUT ANY WARRANTY; without even the implied warranty of
1728 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1729 GNU General Public License for more details.
1731 You should have received a copy of the GNU General Public License
1732 along with this program. If not, see <http://www.gnu.org/licenses/>.