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:
23 m4_joinall m4_set_add m4_set_add_all m4_set_contains
24 m4_set_contents m4_set_delete m4_set_difference m4_set_dump
25 m4_set_empty m4_set_foreach m4_set_intersection m4_set_list
26 m4_set_listc m4_set_remove m4_set_size m4_set_union
28 ** The following m4sugar macros now accept multiple arguments, as is the
29 case with underlying m4:
30 m4_defn m4_popdef m4_undefine
32 ** The following m4sugar macros now guarantee linear scaling; they
33 previously had linear scaling with m4 1.6 but quadratic scaling
34 when using m4 1.4.x. All macros built on top of these also gain
35 the scaling improvements.
36 m4_case m4_do m4_dquote_elt m4_foreach m4_join m4_list_cmp
37 m4_map m4_map_sep m4_max m4_min m4_shiftn
39 ** AT_KEYWORDS once again performs expansion on its argument, such that
40 AT_KEYWORDS([m4_if([$1], [], [default])]) no longer complains about
41 the possibly unexpanded m4_if [regression introduced in 2.62].
43 ** Config header templates `#undef UNDEFINED /* comment */' do not lead to
44 nested comments any more; regression introduced in 2.62.
47 * Major changes in Autoconf 2.62 (2008-04-05) [stable]
48 Released by Eric Blake, based on git versions 2.61a.*.
50 ** Many optimizations have been applied to make overall execution faster.
52 ** Autotest now makes use of shell functions.
54 ** config.status now uses awk instead of sed also for config headers.
56 - As a side effect, AC_DEFINE and AC_DEFINE_UNQUOTED now handle multi-line
57 values, i.e., backslash-newline combinations are handled correctly.
58 Further, for config headers, the total size of values is not limited by
59 the POSIX length limit of text lines any more, only each single line.
61 ** New config variable `top_build_prefix'.
63 ** New Autoconf macros:
64 AC_AUTOCONF_VERSION AC_OPENMP AC_PATH_PROGS_FEATURE_CHECK
66 ** AC_C_BIGENDIAN now supports universal binaries a la Mac OS X.
68 ** AC_C_RESTRICT now prefers to #define 'restrict' to a variant spelling
69 like '__restrict' if the variant spelling is available, as this is
70 more likely to work when mixing C and C++ code.
72 ** AC_CHECK_ALIGNOF's type argument T is now documented better: it must
73 be a string of tokens such that "T y;" is a valid member declaration
76 ** AC_CHECK_SIZEOF now accepts objects as well as types: the general rule
77 is that sizeof (X) works, then AC_CHECK_SIZEOF (X) should work.
79 ** AC_CHECK_TYPE and AC_CHECK_TYPES now work on any C type-name; formerly,
80 they did not work for function types. In C++, they now work on any
81 type-id that can be the operand of sizeof; this is similar to C,
82 except it excludes anonymous struct and union types. Formerly,
83 some (but not all) C++ types involving anonymous struct and union
84 were accepted, though this was not documented.
86 ** AC_CONFIG_LINKS now prefers to link against files in the build tree
87 if found, and it works to link against a file of the same name in
88 the source tree, even if both trees coincide.
90 ** AC_INIT no longer alters $@; regression introduced in 2.60.
92 ** AC_USE_SYSTEM_EXTENSIONS now defines _ALL_SOURCE for Interix platforms.
94 ** AS_HELP_STRING no longer underquotes its first argument; it also handles
95 the case where the first argument contains single-quoted commas.
96 For example, "AS_HELP_STRING([-a, [--arg[=foo]]], [bar])" produces:
97 " -a, --arg[=foo] bar"
98 Additionally, the macro now takes two additional arguments,
99 indent-column and wrap-column; these should not normally be needed,
100 but can be used to fine-tune how the output text is wrapped.
102 ** AC_PROG_INSTALL now requires an install program that can install multiple
103 files into a target directory.
105 ** The command 'autoconf -' now correctly processes a file from stdin.
107 ** 'autoreconf -m' now honors $MAKE.
109 ** For all of the directory arguments for 'configure', such as '--prefix'
110 or '--bindir', trailing slashes are stripped. As an example, if
111 tab completion in the user's shell appends trailing slashes, the
112 command './configure --prefix=/usr/' will still result in an
113 expanded libdir value of /usr/lib, not /usr//lib.
115 ** `configure --help=recursive' now works in read-only trees and from
116 unconfigured build trees.
118 ** If precious variables differ only in whitespace, then the cache consistency
119 check warns instead of fails, and reuses the old value.
121 ** AT_BANNER is now documented.
123 ** AT_SETUP now handles macro expansions properly when calculating line
126 ** Autotest now determines $srcdir correctly.
128 ** Testsuites built by autotest now accept a -C/--directory=DIR option
129 to adjust the working directory prior to creating files.
131 ** Autoconf now requires GNU M4 1.4.5 or later. Earlier versions of M4 have
132 a bug in macro tracing that interferes with the interaction between
133 Autoconf and Automake. GNU M4 1.4.11 or later is recommended. The
134 configure search for a working M4 is improved.
136 ** For portability with the eventual M4 2.0, macros should no longer use
137 anything larger than $9 to refer to arguments.
139 ** Documentation for m4sugar is improved.
141 - The following macros were previously available as undocumented
142 interfaces; the macros are now documented as stable interfaces.
144 __oline__ m4_assert m4_bmatch m4_bpatsubsts m4_car m4_case
145 m4_cdr m4_default m4_divert_once m4_divert_pop m4_divert_push
146 m4_divert_text m4_do m4_errprintn m4_fatal m4_flatten
147 m4_ifndef m4_ifset m4_ifval m4_ifvaln m4_location
148 m4_n m4_shiftn m4_strip m4_warn
150 - The following macros were previously available as undocumented
151 interfaces, but had bug fixes or semantic changes as part of this
152 release. Packages that relied on the undocumented behavior
153 should be analyzed to make sure they will still work with the
154 new documented behavior.
156 m4_cmp m4_list_cmp m4_join m4_map m4_map_sep m4_sign
157 m4_text_box m4_text_wrap m4_version_compare
159 - The m4_wrap macro used to have unspecified order, but now
160 guarantees FIFO order. m4_wrap_lifo was added to guarantee LIFO
163 - Packages using the undocumented m4sugar macro m4_PACKAGE_VERSION
164 should consider using the new AC_AUTOCONF_VERSION instead.
166 - m4sugar macros that are not documented in the manual are still
167 deemed experimental, and should not be used outside of Autoconf.
169 ** The m4sugar macros m4_append and m4_append_uniq, first documented in
170 2.60, have been fixed to treat both the string and the separator
171 arguments consistently with regards to quoting. Prior to this fix,
172 m4_append_uniq could mistakenly duplicate entries if the expansion
173 of the separator resulted in a different string (for example, if it
174 contained quotes, a comma, or a macro name). However, it means
175 that programs previously using
176 m4_append([name], [string], [[, ]])
177 are now using a four-character separator instead of the intended
178 comma and space. If you need portability to earlier versions of
179 Autoconf, you can insert the following snippet after AC_INIT but
180 before any other macro expansions, to enforce the new semantics:
181 m4_pushdef([m4_append], [m4_define([$1],
182 m4_ifdef([$1], [m4_defn([$1])[$3]])[$2])])
183 Additionally, m4_append_uniq now takes optional parameters that can
184 be used to take action depending on whether anything was appended,
185 and warns if a non-empty separator occurs within the string being
186 appended, since that can lead to duplicates.
188 ** The following m4sugar macros are new:
189 m4_append_uniq_w m4_apply m4_combine m4_cond m4_count
190 m4_dquote_elt m4_echo m4_expand m4_ignore m4_make_list m4_max
191 m4_min m4_newline m4_shift2 m4_shift3 m4_unquote m4_wrap_lifo
193 ** Warnings are now generated by default when an installer invokes
194 'configure' with an unknown --enable-* or --with-* option.
195 These warnings can be disabled with the new AC_DISABLE_OPTION_CHECKING
196 macro, or by invoking 'configure' with --disable-option-checking.
198 ** Existing obsolete macros
199 The documentation for the following macros is adjusted to make it
200 more clear that they have previously been marked obsolete, as their
201 functionality can be accomplished by other macros. We have no
202 current plans to remove them from Autoconf.
204 AC_ENABLE AC_STRUCT_ST_BLKSIZE AC_STRUCT_ST_RDEV AC_WITH
206 ** Newly obsolete macros
207 The following macros have been marked obsolete, as they only
208 perform a subset of AC_USE_SYSTEM_EXTENSIONS. We have no current
209 plans to remove them.
211 AC_AIX AC_GNU_SOURCE AC_ISC_POSIX AC_MINIX
213 ** AC_C_LONG_DOUBLE is obsolescent.
214 The documentation now says that AC_C_LONG_DOUBLE is obsolescent: it
215 tests for problems that are so old that it is no longer of
216 practical importance on current systems. New programs need not use
217 AC_C_LONG_DOUBLE. We have no current plans to remove it.
219 ** AC_DIAGNOSE, AC_WARNING, and AC_FATAL are obsolescent.
220 The documentation now favors the use of M4sugar macros m4_warn and
221 m4_fatal, since the naming makes it more obvious that the
222 diagnostics are associated with M4 expansion (ie. when running
223 `autoconf'), and offers less confusion with the AC_MSG_ERROR,
224 AC_MSG_FAILURE, and AC_MSG_WARN macros which manage diagnostics
225 when running `configure'. We have no current plans to remove these
229 * Major changes in Autoconf 2.61a (2006-12-11)
231 ** AC_FUNC_FSEEKO was broken in 2.61; it didn't make fseeko and ftello visible
232 on many platforms. This has been fixed.
234 ** AC_FUNC_SETVBUF_REVERSED is now obsolete. It is still defined for backward
235 compatibility but it does nothing. The macro was already
236 obsolescent, as the last systems to have the problem were those
237 based on SVR2, which became obsolete in 1987. The macro had bugs
238 on some modern systems and could no longer be maintained reliably
239 due to lack of ancient systems to test it on.
241 ** config.status now uses awk instead of sed for most substitutions, for speed.
243 - As a side effect multi-line values of substituted variables no
244 longer have a small limit in total size, though for portability
245 each line should not exceed the POSIX length limit for text lines.
247 - It is now documented that Makefile.in should not contain
248 overlapping variable occurrences, e.g., @VAR1@VAR2@.
249 Autoconf's behavior was always iffy in such cases, and the
250 awk implementation has changed the behavior.
252 ** Many uses of 'echo' have been rewritten so that Autoconf-generated
253 scripts have fewer problems with strings or file names containing
254 embedded special characters such as backslash or leading "-". This
255 was implemented by using `printf '%s\n' "$foo"' instead of `echo
256 "$foo"' when printf works. Due to the implementation technique
257 used, Autoconf-generated scripts now run considerably more slowly
258 on ancient implementations lacking printf. However, this should
259 not be a problem, since Autoconf-generated scripts in practice
260 invariably find a more-modern shell these days.
263 * Major changes in Autoconf 2.61 (2006-11-17)
265 ** New macros AC_C_FLEXIBLE_ARRAY_MEMBER, AC_C_VARARRAYS.
267 ** AC_ARG_ENABLE and AC_ARG_WITH now allow '.' in feature and package names.
270 * Major changes in Autoconf 2.60b (2006-10-22)
273 Autoconf-generated shell scripts no longer export BIN_SH, due to
274 configuration hassles with this. Installers who need BIN_SH in
275 their environment should set it before invoking 'configure' and
276 'make'. As far as we know, this affects only Unixware installations.
278 ** Obsolescent macros
279 The documentation now says that the following macros are obsolescent,
280 as they are superseded by Gnulib:
282 AC_FUNC_FNMATCH AC_FUNC_FNMATCH_GNU AC_FUNC_GETLOADVG AC_REPLACE_FNMATCH
284 New programs should use the Gnulib counterparts of these macros.
285 We have no current plans to remove them from Autoconf.
287 ** AC_COMPUTE_INT no longer caches or reports results.
289 ** AC_CHECK_DECL now also works with aggregate objects.
291 ** AC_USE_SYSTEM_EXTENSIONS now defines _TANDEM_SOURCE for NonStop platforms.
293 ** GNU M4 1.4.7 or later is now recommended.
296 New M4sugar macro, which is more secure than the POSIX M4 maketemp.
299 Now an alias for m4_mkstemp.
301 * Major changes in Autoconf 2.60a (2006-08-25)
303 ** GNU M4 1.4.6 or later is now recommended.
305 ** The check for C99 now tests for varargs macros, as documented.
306 It also tests that the preprocessor supports 64-bit integers.
308 ** Autoconf now uses constructs like "#ifdef HAVE_STDLIB_H" rather than
309 "#if HAVE_STDLIB_H", so that it now works with "gcc -Wundef -Werror".
311 ** The functionality of the undocumented _AC_COMPUTE_INT is now provided
312 by a public and documented macro, AC_COMPUTE_INT. The parameters to the
313 two macros are different, so autoupdate will not change the old private name
314 to the new one. _AC_COMPUTE_INT may be removed in a future release.
316 ** AC_TYPE_LONG_LONG_INT and AC_TYPE_UNSIGNED_LONG_LONG_INT now require
317 that long long types be at least 64 bits wide, as C99 and tradition
318 requires. Formerly, they accepted implementations of any width.
321 * Major changes in Autoconf 2.60
323 Released 2006-06-23, by Ralf Wildenhues.
325 ** Autoconf no longer depends on whether m4wrap is FIFO (as Posix requires)
326 or LIFO (as in GNU M4 1.4.x). GNU M4 2.0 is expected to conform to Posix
327 here, so m4wrap/m4_wrap users should no longer depend on LIFO behavior.
329 ** Provide a way to turn off warnings about the changed directory variables.
331 * Major changes in Autoconf 2.59d
333 Released 2006-06-05, by Ralf Wildenhues.
335 ** GNU make now recommended for VPATH builds
336 INSTALL now suggests VPATH builds (e.g., "sh ../srcdir/configure")
337 only if you use GNU make. In practice, other 'make' implementations
338 have too many subtle incompatibilities in their support for VPATH.
339 Many packages (including Autoconf itself) are portable to other
340 'make' implementations, but some packages are not, and recommending
341 GNU make keeps the installation instructions simpler.
343 ** Even more safety checks for the new Directory variables:
344 Warn about suspicious `${datarootdir}' found in config files output.
346 ** AC_TRY_COMMAND, AC_TRY_EVAL, ac_config_guess, ac_config_sub, ac_configure
347 These never-documented macros and variables have been marked with
348 comments saying that they may be removed in a future release,
349 because their use can lead to unintended code being executed.
350 If you need functionality that only these macros or variables
351 currently supply, please write bug-autoconf@gnu.org.
353 ** AC_SUBST, AC_DEFINE
354 Literal arguments to these are passed to m4_pattern_allow now.
357 Passing 'ac_cv_prog_cc_stdc=no' to 'configure' now sets ac_cv_prog_cc_c99
358 and ac_cv_prog_cc_c89 to 'no' as well, for backward compatibility with
359 obsolete K&R tests in the Automake test suite.
368 Now more robust with special characters in file names, or when
369 multiple processes create the same directory at the same time.
371 ** Obsolescent macros
372 The documentation now says that the following macros are obsolescent:
373 they test for problems that are so old that they are no longer of
374 practical importance on current systems.
376 AC_C_BACKSLASH_A AC_FUNC_MEMCMP AC_HEADER_DIRENT
377 AC_C_CONST AC_FUNC_SELECT_ARGTYPES AC_HEADER_STAT
378 AC_C_PROTOTYPES AC_FUNC_SETPGRP AC_HEADER_STDC
379 AC_C_STRINGIZE AC_FUNC_SETVBUF_REVERSED AC_HEADER_SYS_WAIT
380 AC_C_VOLATILE AC_FUNC_STAT AC_HEADER_TIME
381 AC_FUNC_CLOSEDIR_VOID AC_FUNC_STRFTIME AC_ISC_POSIX
382 AC_FUNC_GETPGRP AC_FUNC_UTIME_NULL AC_PROG_GCC_TRADITIONAL
383 AC_FUNC_LSTAT AC_FUNC_VPRINTF AC_STRUCT_TM
385 New programs need not use these macros. We have no current plans to
389 For compatibility with future Libtool 2.0, autoreconf will invoke
390 libtoolize with the option `--ltdl' now, if LT_CONFIG_LTDL_DIR is
393 * Major changes in Autoconf 2.59c
395 Released 2006-04-12, by Ralf Wildenhues.
397 ** The configure command now redirects standard input from /dev/null,
398 to help avoid problems with subsidiary commands that might mistakenly
399 read standard input. AS_ORIGINAL_STDIN_FD points to the original
400 standard input before this redirection, if you really want configure to
401 read from standard input.
403 ** Directory variables adjusted to recent changes in the GNU Coding Standards.
404 The following directory variables are new:
406 datarootdir read-only architecture-independent data root [PREFIX/share]
407 localedir locale-specific message catalogs [DATAROOTDIR/locale]
408 docdir documentation root [DATAROOTDIR/doc/PACKAGE]
409 htmldir html documentation [DOCDIR]
410 dvidir dvi documentation [DOCDIR]
411 pdfdir pdf documentation [DOCDIR]
412 psdir ps documentation [DOCDIR]
414 The following variables have new default values:
416 datadir read-only architecture-independent data [DATAROOTDIR]
417 infodir info documentation [DATAROOTDIR/info]
418 mandir man documentation [DATAROOTDIR/man]
420 This means that if you use any of `@datadir@', `@infodir@', or
421 `@mandir@' in a file, you will have to ensure `${datarootdir}' is
422 defined in this file. As a temporary measure, if any of those are
423 found but no mention of `datarootdir', the substitutions will be
424 replaced with values that do not contain `${datarootdir}', and a
425 warning will be issued.
427 ** @top_builddir@ is now a dir name: it is always nonempty and doesn't have
428 a trailing slash. Similar change will be made to ac_top_builddir in a
429 future release; the old style value, which matches (../)*, is (and will
430 continue to be) available as ac_top_build_prefix.
433 New macro to check for support of 'typeof' syntax a la GNU C.
435 ** AC_CHECK_DECLS_ONCE, AC_CHECK_FUNCS_ONCE, AC_CHECK_HEADERS_ONCE
436 New "once-only" variants of commonly-used macros, to make 'configure'
437 smaller and faster in common cases.
440 New macro to check for strtold with C99 semantics.
443 New macro that lets builder disable assertions at 'configure'-time.
446 Now checks for X11/Xlib.h and XrmInitialize (X proper) rather than
447 X11/Intrinsic.h and XtMalloc (Xt).
449 ** AC_PRESERVE_HELP_ORDER
450 New macro that causes `configure' to display help strings for AC_ARG_ENABLE
451 and AC_ARG_WITH arguments in one region, in the order defined. The default
452 behavior is to group options of each classes separately.
454 ** AC_PROG_CC, AC_PROG_CXX
455 No longer automatically arrange to declare the 'exit' function of C,
456 when a C++ compiler is used. Standard Autoconf macros no longer use
457 'exit', so this is no longer an issue for them. If you use C++, and
458 want to call 'exit', you'll have to arrange for its declaration
459 yourself. But we now suggest you return from 'main' instead.
461 ** AC_PROG_CC_C89, AC_PROG_CC_C99
462 New macros for ISO C99 support. AC_PROG_CC_C89 and AC_PROG_CC_C99
463 check for ANSI C89 and ISO C99 support respectively.
466 Has been unobsoleted, and will check if the compiler supports ISO
467 C99, falling back to ANSI C89 if not. ac_cv_prog_cc_stdc is
468 retained for backwards compatibility, assuming the value of
469 ac_cv_prog_cc_c99 or ac_cv_prog_cc_c89 (whichever is valid, in
472 ** AC_STRUCT_DIRENT_D_INO, AC_STRUCT_DIRENT_D_TYPE
473 New macros for checking commonly-used members of struct dirent.
476 The substituted value can now contain newlines.
479 The substitution now occurs only when @variable@ is on a line by itself,
480 optionally surrounded by spaces and tabs. The whole line is replaced.
482 ** AC_TYPE_LONG_DOUBLE, AC_TYPE_LONG_DOUBLE_WIDER
483 New macros to check for long double, and whether it is wider than double.
484 The old macro AC_C_TYPE_LONG_DOUBLE has been marked as obsolete;
485 applications should switch to the new macro.
487 ** AC_TYPE_INT8_T, AC_TYPE_INT16_T, AC_TYPE_INT32_T, AC_TYPE_INT64_T,
488 AC_TYPE_INTMAX_T, AC_TYPE_INTPTR_T, AC_TYPE_LONG_LONG_INT, AC_TYPE_SSIZE_T,
489 AC_TYPE_UINT8_T, AC_TYPE_UINT16_T, AC_TYPE_UINT32_T, AC_TYPE_UINT64_T,
490 AC_TYPE_UINTMAX_T, AC_TYPE_UINTPTR_T, AC_TYPE_UNSIGNED_LONG_LONG_INT
491 New macros to check for C99 and POSIX types.
493 ** AC_USE_SYSTEM_EXTENSIONS
494 New macro to enable extensions to Posix.
497 New macro which is defined to the name of the first declared config header
498 or undefined if no config headers have been declared yet.
501 The macro correctly handles quadrigraphs now.
503 ** AS_BOURNE_COMPATIBLE, AS_SHELL_SANITIZE, AS_CASE
504 These macros are new or published now.
507 New macro for copyright notices in testsuite files.
509 ** ALLOCA, LIBOBJS, LTLIBOBJS
510 Object names added to these variables are now prefixed with `${LIBOBJDIR}',
511 as in `${LIBOBJDIR}alloca.o'. LIBOBJDIR is meant to be defined from
512 `Makefile.in' in case the object files lie in a different directory.
513 The LIBOBJDIR feature is experimental.
516 Supports --no-recursive now.
518 ** New macros to support Erlang/OTP.
519 New macros for configuring paths to Erlang tools and libraries:
520 AC_ERLANG_PATH_ERLC, AC_ERLANG_NEED_ERLC, AC_ERLANG_PATH_ERL,
521 AC_ERLANG_NEED_ERL, AC_ERLANG_CHECK_LIB, AC_ERLANG_SUBST_ROOT_DIR,
522 AC_ERLANG_SUBST_LIB_DIR.
524 New macros for configuring installation of Erlang libraries:
525 AC_ERLANG_SUBST_INSTALL_LIB_DIR, AC_ERLANG_SUBST_INSTALL_LIB_SUBDIR.
527 ** The manual now mentions Gnulib more prominently.
529 ** New macros to support Objective C.
530 AC_PROG_OBJC, AC_PROG_OBJCPP.
532 * Major changes in Autoconf 2.59b
534 Released 2004-08-20, by Paul Eggert.
537 New macro that computes the default alignment of a type.
539 ** AC_CHECK_TOOL, AC_PATH_TOOL, AC_CHECK_TOOLS
540 When cross-compiling, these macros will give a warning if the tool
541 is not prefixed. In the future, unprefixed cross tools will not
542 be detected; please consult the info documentation for information
543 about the reason of this change.
545 ** AC_CHECK_TARGET_TOOL, AC_PATH_TARGET_TOOL, AC_CHECK_TARGET_TOOLS
546 New macros that detect programs whose name is prefixed with the
547 target type, if the build type and target type are different.
549 ** AC_REQUIRE_AUX_FILE
550 New trace macro that declares expected auxiliary files.
553 New macro that tests for a grep program that accepts as a long a line
556 ** AC_PROG_EGREP, AC_PROG_FGREP
557 These macros now require AC_PROG_GREP, and try EGREP="$GREP -E" and
558 FGREP="$GREP -F" respectively if possible, or else run a path search for
559 a program that accepts as long a line as possible.
562 New macro that tests for a sed program that truncates as few characters
565 * Major changes in Autoconf 2.59
567 Released 2003-11-04, by Akim Demaille
569 ** ac_abs_builddir etc.
570 Absolute file names were actually relative in 2.58.
572 * Major changes in Autoconf 2.58
574 Released 2003-11-04, by Akim Demaille
577 core.* files are no longer removed, as they may be valid user files.
579 ** autoreconf and auxiliary directory
580 Autoreconf creates the auxiliary directory if needed. This is
581 especially useful for initial "bootstrapping" of fresh CVS checkouts.
583 ** AC_CONFIG_MACRO_DIR
584 Use this macro to declare the directory for local M4 macros for aclocal.
587 No longer includes twice the same file in LIBOBJS if invoked
590 ** AC_CONFIG_COMMANDS
591 The directory for its first argument is automatically created. For
594 AC_CONFIG_COMMANDS([src/modules.hh], [...])
596 $top_builddir/src/ is created if needed.
598 ** Autotest and local.at
599 The optional file local.at is always included in Autotest test suites.
602 The warnings are always issued, including with cached runs.
603 This became a significant problem since aclocal and automake can
604 run autoconf behind the scene.
606 ** autoheader warnings
607 The warnings of autoheader can be turned off, using --warning.
608 For instance, -Wno-obsolete disables the complaints about acconfig.h
609 and other deprecated constructs.
612 AC_C_RESTRICT, AC_INCLUDES_DEFAULT, AC_LANG_ASSERT, AC_LANG_WERROR,
615 ** AC_DECL_SYS_SIGLIST
619 Now checks that mktime is the inverse of localtime.
621 ** Improve DJGPP portability
622 The Autoconf tools and configure behave better under DJGPP.
624 ** Present But Cannot Be Compiled
625 New FAQ section dedicated to the mystic
627 configure: WARNING: pi.h: present but cannot be compiled
628 configure: WARNING: pi.h: check for missing prerequisite headers?
629 configure: WARNING: pi.h: proceeding with the preprocessor's result
632 ** Concurrent executions of autom4te
633 autom4te now locks its internal files, which enables concurrent
634 executions of autom4te, likely to happen if automake, autoconf,
635 autoheader etc. are run simultaneously.
638 Use of Libtool 1.5 and higher is encouraged. Compatibility with
639 Libtool pre-1.4 is not checked.
642 Testsuites no longer rerun failed tests in verbose mode; instead,
643 failures are logged while the test is run.
645 In addition, expected failures can be marked as such.
647 * Major changes in Autoconf 2.57
649 Released 2002-12-03 by Paul Eggert.
651 Bug fixes for problems with AIX linker, with freestanding C compilers,
652 with GNU M4 limitations, and with obsolete copies of GNU documents.
654 The Free Documentation License has been upgraded from 1.1 to 1.2.
656 * Major changes in Autoconf 2.56
658 Released 2002-11-15 by Akim Demaille.
660 One packaging problem fixed (config/install-sh was not executable).
662 * Major changes in Autoconf 2.55
664 Released 2002-11-14 by Akim Demaille.
668 Have your configure.ac checked by autoscan ("autoscan").
669 Try the warning options ("autoreconf -fv -Wall").
673 - AC_CHECK_HEADER, AC_CHECK_HEADERS
674 More information on proper use.
676 - Writing Test Programs
678 This sections explains how to write good test sources to use with
679 AC_COMPILE_IFELSE etc. It documents AC_LANG_PROGRAM and so forth.
681 - AC_FOO_IFELSE vs. AC_TRY_FOO
683 Explains why Autoconf moves from AC_TRY_COMPILE etc. to
684 AC_COMPILE_IFELSE and AC_LANG_PROGRAM etc.
688 - Is more robust to different Gettext installations.
690 - Produces messages (when --verbose) to be understood by Emacs'
693 - Supports -W/--warnings.
696 Once the GNU Build System reinstalled, run `./config.status
697 --recheck && ./config.status && make' if possible.
701 - Supports --cache, and --no-cache.
703 - ~/.autom4te.cfg makes it possible to disable the caching mechanism
704 (autom4te.cache). See `Customizing autom4te' in the documentation.
711 Support for the obsoleted options -m, --macrodir, -l, --localdir is
712 dropped in favor of the safer --include/--prepend-include scheme.
717 AC_COMPILER_IFELSE, AC_FUNC_MBRTOWC, AC_HEADER_STDBOOL,
718 AC_LANG_CONFTEST, AC_LANG_SOURCE, AC_LANG_PROGRAM, AC_LANG_CALL,
719 AC_LANG_FUNC_TRY_LINK, AC_MSG_FAILURE, AC_PREPROC_IFELSE.
722 Obsoleted macros are kept for Autoconf backward compatibility, but
723 should be avoided in configure.ac. Running autoupdate is advised.
726 - AC_DEFINE/AC_DEFINE_UNQUOTED
728 We have to stop using the old compatibility scheme --that tried to
729 avoid useless backslashes-- because Libtool 1.4.3 contains a
731 AC_DEFINE([error_t], [int],
732 [Define to a type to use for \`error_t' if it is not
733 otherwise available.])
735 We have to quote the single quotes and backslashes with \. The old
736 compatibility scheme saw that ` was backslashed, and therefore did
737 not quote the single quote... Failure. Hence, Autoconf 2.54 is not
738 compatible with Libtool. Autoconf 2.55 is, but in some cases might
739 produce more \ than wanted.
741 Please, note that in the future the same problem will happen with
742 AC_MSG_*: use `autoreconf -f -Wall'.
746 - Portability of the Autoconf package to Solaris.
748 - Spurious warnings caused by config.status.
749 This bug is benign, but painful: on some systems (typically
750 FreeBSD), warnings such as:
752 config.status: creating Makefile
753 mv: Makefile: set owner/group (was: 1357/0): Operation not permitted
755 could be issued. This is fixed.
758 Simultaneous executions of config.status are possible again.
760 - Precious variables accumulation
762 config.status could stack several copies of the precious variables
766 ** Plans for later versions
770 The compatibility hooks with the old scheme will be completely
771 removed. Please, advice/use `--build', `--host', and `--target'
774 - AC_CHECK_HEADER, AC_CHECK_HEADERS
776 The tests will be stricter, please make sure your invocations are
781 Shell functions will gradually be introduced, probably starting with
782 Autotest. If you know machines which are in use that you suspect
783 *not* to support shell functions, please run the test suite of
784 Autoconf 2.55 on it, and report the results to
785 bug-autoconf@gnu.org.
789 Special characters in AC_MSG_* need not be quoted. Currently,
790 Autoconf has heuristics to decide when a string is escaped, or has
791 to be escaped. This scheme is fragile, and will be removed; the
792 only risk is uglified messages. Please, run `autoreconf -f -Wall'
793 to find occurrences that will be affected.
795 * Major changes in Autoconf 2.54
797 Released 2002-09-13 by Akim Demaille.
801 - autoreconf no longer changes the version of the gettext/po/intl
802 support files. It now adds the files the correspond to the
803 AM_GNU_GETTEXT_VERSION declared in configure.ac.
805 Warning: It now relies on the 'autopoint' program, which is part
806 of GNU gettext 0.11.4 and newer.
808 Please note that you need to have a GNU gettext version that
809 corresponds at least to the AM_GNU_GETTEXT_VERSION declared
810 in configure.ac. You can upgrade to newer GNU gettext versions,
811 though, without needing to change configure.ac.
813 - The -I DIR or --include=DIR option now appends DIR to the include path
814 instead of prepending; this is for consistency with other GNU tools.
815 The new -B DIR or --prepend-include=DIR option has the old behavior.
820 Now handles all the gory details about LIBOBJS and LTLIBOBJS.
821 Please, remove lines such as
823 # This is necessary so that .o files in LIBOBJS are also
824 # built via the ANSI2KNR-filtering rules.
825 LIBOBJS=`echo $LIBOBJS|sed 's/\.o /\$U.o /g;s/\.o$/\$U.o/'`
827 and read the `AC_LIBOBJ vs LIBOBJS' section. Do not define U in
828 your Makefiles either.
830 - AC_CONFIG_LINKS now makes copies if it can't make links.
832 - AC_FUNC_FNMATCH now tests only for POSIX compatibility, reverting to
833 Autoconf 2.13 behavior. The new macro AC_FUNC_FNMATCH_GNU also
834 tests for GNU extensions to fnmatch, and replaces fnmatch if needed.
836 - AC_FUNC_SETVBUF_REVERSED no longer fails when cross-compiling.
838 - AC_PROG_CC_STDC is integrated into AC_PROG_CC.
840 - AC_PROG_F77 default search no longer includes cf77 and cfg77.
844 AC_C_BACKSLASH_A, AC_CONFIG_LIBOBJ_DIR, AC_GNU_SOURCE,
845 AC_PROG_EGREP, AC_PROG_FGREP, AC_REPLACE_FNMATCH,
846 AC_FUNC_FNMATCH_GNU, AC_FUNC_REALLOC, AC_TYPE_MBSTATE_T.
849 looks for getloadavg.c in the CONFIG_LIBOBJ_DIR.
852 Now defines HAVE_MALLOC to 0 if `malloc' does not work, and asks
853 for an AC_LIBOBJ replacement.
857 - Spurious complaints from `m4_bmatch' about invalid regular
858 expressions are suppressed.
860 - Empty top_builddirs are properly handled.
862 - AC_CHECK_MEMBER works correctly when the member is an aggregate.
865 Now colon in the optional path arguments are properly handled.
867 ** Improved portability
869 - Both Autoconf the package, and the scripts it produces, should run
870 more reliably with Zsh. Bear in mind it is the default Bourne shell
873 - Autoconf and the scripts it produces no longer assume the existence of
874 the obsolescent commands egrep and fgrep.
878 - Limitations of Make
882 The GNATS base moved to
883 http://bugs.gnu.org/cgi-bin/gnatsweb.pl?database=autoconf
884 (It is no longer available, though.)
889 Now contains the list of ouput variables and files (AC_SUBST,
892 * Major changes in Autoconf 2.53
894 Released 2002-03-08 by Akim Demaille.
898 Perl 5.005_03 or later is required: autom4te is written in Perl and is
899 needed by autoconf. autoheader, autoreconf, ifnames, and autoscan are
905 Argument requirements, output variables, defined macros.
906 - M4sugar, M4sh, Autotest
908 - Double quoting macros
909 AC_TRY_CPP, AC_TRY_COMPILE, AC_TRY_LINK and AC_TRY_RUN.
911 The Autoconf manual is now distributed under the terms of the GNU FDL.
912 - Section `Hosts and Cross-Compilation'
913 Explains the rationale for the 2.5x changes in the cross-compilation
914 chain, and in the relationships between build, host, and target
916 Emphasizes that `cross-compilation' == `--host is given'.
917 If you are working on compilers etc., be sure to read this section.
918 - Section `AC_LIBOBJ vs. LIBOBJS'
919 Explains why assigning LIBOBJS directly is now an error.
920 Details how to update the code.
925 Now used instead of hard coded line numbers.
926 This eases the comparison of `configure's, and diminishes the
927 pressure over control version archives.
928 Automatic replacement for shells that don't support this feature.
929 - New output variables
930 @builddir@, @top_builddir@, @abs_srcdir@, @abs_top_srcdir@, @abs_builddir@,
935 Autoconf and Autotest modes are provided.
940 New, used by the Autoconf suite to cache and speed up most processing.
942 Supported by autom4te, autoconf and autoheader.
944 Replaces --autoconf-dir and --localdir in autoconf, autoheader,
945 autoupdate, and autoreconf.
947 No longer passes --cygnus, --foreign, --gnits, --gnu, --include-deps:
948 automake options are to be given via AUTOMAKE_OPTIONS.
950 Runs gettextize and libtoolize when appropriate.
952 --m4dir is no longer supported.
954 Now runs only in the specified directories, defaulting to `.',
955 but understands AC_CONFIG_SUBDIRS for dependent directories.
956 Before, it used to run on all the `configure.ac' found in the
958 Independent packages are properly updated.
962 - The top level $prefix is propagated to the AC_CONFIG_SUBDIRS configures.
964 Under the user pressure, $? is finally available. Probably a mistake.
965 - AC_F77_LIBRARY_LDFLAGS now supports the HP/UX f90 compiler.
966 - Precious variables accumulation
967 config.status could stack several copies of the precious variables
969 - AC_PATH_PROG and family.
970 Works properly when given a literal path.
972 Somewhere since 2.13, the result had been reversed.
976 - AC_C_BIGENDIAN supports the cross-compiling case.
977 - AC_C_BIGENDIAN accepts ACTION-IF-TRUE, ACTION-IF-FALSE, and
978 ACTION-IF-UNKNOWN arguments. All are facultative, and the default
979 for ACTION-IF-TRUE is to define WORDS_BIGENDIAN like AC_C_BIGENDIAN
981 - AC_C_LONG_DOUBLE now succeeds only if `long double' has more range or
982 precision than `double'.
987 It now defines the preprocessor symbols PACKAGE_NAME,
988 PACKAGE_TARNAME, PACKAGE_VERSION, PACKAGE_STRING, and
992 Admits a fourth optional parameter: the tar name.
994 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS.
995 Provide the user with srcdir, ac_srcdir, ac_top_srcdir, ac_builddir,
996 ac_top_builddir, ac_abs_srcdir, ac_abs_top_srcdir, ac_abs_builddir,
999 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS and AC_OUTPUT.
1000 Are much less expensive when using long lists of files.
1003 Works with shell variables, and non alphanumeric names.
1007 - AC_FUNC_STRERROR_R now sets STRERROR_R_CHAR_P, not HAVE_WORKING_STRERROR_R,
1008 because POSIX 1003.1-200x draft 7 says strerror_r returns int, not char *.
1010 - AC_FUNC_STRTOD substitutes POW_LIB.
1015 * Major changes in Autoconf 2.52
1017 Released 2001-07-18 by Akim Demaille.
1022 This feature was present in autoconf 2.50 but was not documented.
1023 For example, `@<:@' is translated to `[' just before output. This
1024 is useful when writing strings that contain unbalanced quotes, or
1025 other hard-to-quote constructs.
1026 - m4_pattern_forbid, m4_pattern_allow
1027 - Tips for upgrading from 2.13.
1028 - Using autoscan to maintain a configure.ac.
1031 - Now include stdint.h.
1032 - sys/types.h and sys/stat.h are guarded.
1033 - strings.h is included if available, and not conflicting with string.h.
1036 - The test suite is more robust and presents less false failures.
1037 - Invocation of GNU M4 now robust to POSIXLY_CORRECT.
1038 - configure accepts --prefix='' again.
1039 - AC_CHECK_LIB works properly when its first argument is not a
1041 - HAVE_INTTYPES_H is defined only if not conflicting with sys/types.h.
1042 - build_, host_, and target_alias are AC_SUBST as in 2.13.
1043 - AC_ARG_VAR properly propagates precious variables inherited from the
1044 environment to ./config.status.
1045 - Using --program-suffix/--program-prefix is portable.
1046 - Failures to detect the default compiler's output extension are less
1048 - `config.status foo' works properly when `foo' depends on variables
1049 set in an AC_CONFIG_THING INIT-CMD.
1050 - autoheader is more robust to broken input.
1051 - Fixed Fortran name-mangling and link tests on a number of systems,
1052 e.g. NetBSD; see AC_F77_DUMMY_MAIN, below.
1055 - AC_CHECK_HEADER and AC_CHECK_HEADERS support a fourth argument to
1056 specify pre-includes. In this case, the headers are compiled with
1057 cc, not merely preprocessed by cpp. Therefore it is the _usability_
1058 of a header which is checked for, not just its availability.
1059 - AC_ARG_VAR refuses to run configure when precious variables have
1061 - Versions of compilers are dumped in the logs.
1062 - AC_CHECK_TYPE recognizes use of `foo_t' as a replacement type.
1065 - AC_PATH_XTRA only adds -ldnet to $LIBS if it's needed to link.
1066 - AC_FUNC_WAIT3 and AC_SYS_RESTARTABLE_SYSCALLS are obsoleted.
1067 - AM_FUNC_ERROR_AT_LINE, AM_FUNC_FNMATCH, AM_FUNC_MKTIME,
1068 AM_FUNC_OBSTACK, and AM_FUNC_STRTOD are now activated.
1069 Be sure to read `Upgrading from Version 2.13' to understand why
1070 running `autoupdate' is needed.
1071 - AC_F77_DUMMY_MAIN, AC_F77_MAIN: new macros to detect whether
1072 a main-like routine is required/possible when linking C/C++ with
1073 Fortran. Users of e.g. AC_F77_WRAPPERS should be aware of these.
1074 - AC_FUNC_GETPGRG behaves better when cross-compiling.
1076 * Major changes in Autoconf 2.51
1077 There was no release of Autoconf 2.51 since some packagers had used
1078 this version number without permission to ship intermediary versions
1079 of 2.50. The version was skipped to avoid confusion.
1081 * Major changes in Autoconf 2.50
1083 Released 2001-05-21 by Akim Demaille.
1085 ** Lots of bug fixes
1086 There have been far too many to enumerate them here. Check out
1087 ChangeLog if you really want to know more.
1089 ** Improved documentation
1090 In particular, portability issues are better covered.
1093 All the standard GNU Makefile targets are supported. The layout has
1094 changed: m4/ holds the M4 extensions Autoconf needs for its
1095 configuration, doc/ contains the documentation, and tests/ contains
1098 ** Man pages are provided
1099 For autoconf, autoreconf, autoupdate, autoheader, autoscan, ifnames,
1100 config.guess, config.sub.
1104 Provides a safe and powerful means to trace the macro uses. This
1105 provide the parsing layer for tools which need to `study'
1109 Specify what category of warnings should be enabled.
1111 - When recursing into subdirectories, try for configure.gnu before
1112 configure to adapt for packages not using autoconf on case-insensitive
1116 More errors are now caught (circular AC_REQUIRE dependencies,
1117 AC_DEFINE in the action part of an AC_CACHE_CHECK, too many pops
1118 etc.). In addition, their location and call stack are given.
1121 autoupdate is much more powerful, and is able to provide the glue code
1122 which might be needed to move from an old macro to its newer
1125 You are strongly encouraged to use it to modernize both your
1126 `configure.in' and your .m4 extension files.
1129 The internal machinery of autoheader has completely changed. As a
1130 result, using `acconfig.h' should be considered to be obsoleted, and
1131 you are encouraged to get rid of it using the AH macros.
1136 ** Fortran 77 compilers
1137 Globally, the support for Fortran 77 is considerably improved.
1139 Support for automatically determining a Fortran 77 compiler's
1140 name-mangling scheme. New CPP macros F77_FUNC and F77_FUNC_ are
1141 provided to wrap C/C++ identifiers, thus making it easier and more
1142 transparent for C/C++ to call Fortran 77 routines, and Fortran 77 to
1143 call C/C++ routines. See the Texinfo documentation for details.
1146 The test suite no longer uses DejaGNU. It should be easy to submit
1147 test cases in this new framework.
1150 - --help, --help=long, -hl
1151 no longer dumps useless items.
1153 lists only specific options.
1154 - --help=recursive, -hr
1155 displays the help of all the embedded packages.
1156 - Remembers environment variables when reconfiguring.
1157 The previous scheme to set envvar before running configure was
1159 what prevented configure from remembering the environment in which
1160 it was run, therefore --recheck was run in an inconsistent
1161 environment. Now, one should run
1163 and then --recheck will work properly. Variables declared with
1164 AC_ARG_VAR are also preserved.
1166 $build defaults to `config.guess`, $host to $build, and then $target
1168 Cross-compilation is a global status of the package, it no longer
1169 depends upon the current language.
1170 Cross compilation is enabled iff the user specified `--host'.
1171 `configure' now fails if it can't run the executables it compiles,
1172 unless cross-compilation is enabled.
1174 The cache file is disabled by default. The new options
1175 `--config-cache', `-C' set the cache to `config.cache'.
1179 Much faster on most architectures.
1180 - concurrent executions
1181 It is safe to use `make -j' with config.status.
1182 - human interface improved
1183 It is possible to invoke
1184 ./config.status foobar
1185 instead of the former form (still valid)
1186 CONFIG_COMMANDS= CONFIG_HEADERS= CONFIG_LINKS= \
1187 CONFIG_FILES=foobar:foo.in:bar.in \
1189 The same holds for configuration headers and links.
1190 You can instantiate unknown files and headers:
1191 ./config.status --header foo.h:foo.h.in --file bar:baz
1192 - has a useful --help
1193 - accepts special file name "-" for stdin/stdout
1198 Specify additional copyright information.
1201 Now expects the identity of the package as argument.
1205 Most macros, if not all, now strictly follow the `one quotation
1206 level' rule. This results in a more predictable expansion.
1209 A sly bug in the AC_REQUIRE machinery, which could produce incorrect
1210 configure scripts, was fixed by Axel Thimm.
1214 Document and ask for the registration of an envvar.
1217 Specifies the file which `configure' should look for when trying to
1218 find the source tree (used to be handled by AC_INIT).
1220 - AC_CONFIG_COMMANDS
1221 To add new actions to config.status. Should be used instead of
1225 Replaces AC_LINK_FILES.
1227 - AC_CONFIG_HEADERS, AC_CONFIG_COMMANDS, AC_CONFIG_SUBDIRS,
1228 AC_CONFIG_LINKS, and AC_CONFIG_FILES
1229 They now obey sh: you should no longer use shell variables as
1230 argument. Instead of
1232 test "$package_foo_enabled" = yes && $my_subdirs="$my_subdirs foo"
1233 AC_CONFIG_SUBDIRS($my_subdirs)
1237 if test "$package_foo_enabled" = yes; then
1238 AC_CONFIG_SUBDIRS(foo)
1242 To format an Autoconf macro's help string so that it looks pretty
1243 when the user executes `configure --help'.
1246 ** Generic Test Macros
1248 The interface of the AC_CHECK families of macros (decl, header,
1249 type, member, func) is now uniform. They support the same set of
1252 - AC_CHECK_DECL, AC_CHECK_DECLS
1253 To check whether a symbol is declared.
1255 - AC_CHECK_SIZEOF, AC_C_CHAR_UNSIGNED.
1256 No longer need a cross-compilation default.
1259 The test it performs is much more robust than previously, and makes
1260 it possible to test builtin types in addition to typedefs.
1261 It is now schizophrenic:
1262 - AC_CHECK_TYPE(TYPE, REPLACEMENT)
1263 remains for backward compatibility, but its use is discouraged.
1264 - AC_CHECK_TYPE(TYPE, IF-FOUND, IF-NOT-FOUND, INCLUDES)
1265 behaves exactly like the other AC_CHECK macros.
1268 Checks whether given types are supported by the system.
1270 - AC_CHECK_MEMBER, AC_CHECK_MEMBERS
1271 Check for given members in aggregates (e.g., pw_gecos in struct
1275 Checks if the compiler supports ISO C, included when needs special
1279 Checking whether the preprocessor indicates missing includes by the
1280 error code. stderr is checked by AC_TRY_CPP only as a fallback.
1283 Takes a language as argument and replaces AC_LANG_C,
1284 AC_LANG_CPLUSPLUS and AC_LANG_FORTRAN77.
1286 - AC_LANG_PUSH, AC_LANG_POP
1287 Are preferred to AC_LANG_SAVE, AC_LANG_RESTORE.
1290 - AC_FUNC_CHOWN, AC_FUNC_MALLOC, AC_FUNC_STRERROR_R,
1291 AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK, AC_FUNC_STAT, AC_FUNC_LSTAT,
1292 AC_FUNC_ERROR_AT_LINE, AC_FUNC_OBSTACK, AC_FUNC_STRTOD, AC_FUNC_FSEEKO.
1296 Sets GETGROUPS_LIBS.
1298 - AC_FUNC_GETLOADAVG
1299 Defines `HAVE_STRUCT_NLIST_N_UN_N_NAME' instead of `NLIST_NAME_UNION'.
1302 Now integrates `AC_DECL_YYTEXT' which is obsoleted.
1305 Arrange for large-file support.
1307 - AC_EXEEXT, AC_OBJEXT
1308 You are no longer expected to use them: their computation is
1309 performed by default.
1311 ** C++ compatibility
1312 Every macro has been revisited in order to support at best CC=c++.
1314 Major changes in Autoconf 2.14:
1315 There was no release of GNU Autoconf 2.14.
1317 Major changes in Autoconf 2.13:
1319 Released 1999-05-01 by Ben Elliston.
1321 * Support for building on Win32 systems where the only available C or
1322 C++ compiler is the Microsoft Visual C++ command line compiler
1323 (`cl'). Additional support for building on Win32 systems which are
1324 using the Cygwin or Mingw32 environments.
1325 * Support for alternative object file and executable file extensions.
1326 On Win32, for example, these are .obj and .exe. These are discovered
1327 using AC_OBJEXT and AC_EXEEXT, which substitute @OBJEXT@ and
1328 @EXEEXT@ in the output, respectively.
1329 * New macros: AC_CACHE_LOAD, AC_CACHE_SAVE, AC_FUNC_SELECT_ARGTYPES,
1330 AC_VALIDATE_CACHED_SYSTEM_TUPLE, AC_SEARCH_LIBS, AC_TRY_LINK_FUNC,
1331 AC_C_STRINGIZE, AC_CHECK_FILE(S), AC_PROG_F77 (and friends).
1332 * AC_DEFINE now has an optional third argument for a description to be
1333 placed in the config header input file (e.g. config.h.in).
1334 * The C++ code fragment compiled for the C++ compiler test had to be
1335 improved to include an explicit return type for main(). This was
1336 causing failures on systems using recent versions of the EGCS C++
1338 * Fixed an important bug in AC_CHECK_TYPE that would cause a configure
1339 script to report that `sometype_t' was present when only `type_t'
1341 * Merge of the FSF version of config.guess and config.sub to modernize
1342 these scripts. Add support for a few new hosts in config.guess.
1343 Incorporate latest versions of install-sh, mkinstalldirs and
1344 texinfo.tex from the FSF.
1345 * autoreconf is capable of running automake if necessary (and
1347 * Support for Fortran 77. See the Texinfo documentation for details.
1348 * Bug fixes and workarounds for quirky bugs in vendor utilities.
1350 Major changes in Autoconf 2.12:
1352 Released 1996-11-26 by David J. MacKenzie
1354 * AC_OUTPUT and AC_CONFIG_HEADER can create output files by
1355 concatenating multiple input files separated by colons, like so:
1356 AC_CONFIG_HEADER(config.h:conf.pre:config.h.in:conf.post)
1357 AC_OUTPUT(Makefile:Makefile.in:Makefile.rules)
1358 The arguments may be shell variables, to compute the lists on the fly.
1359 * AC_LINK_FILES and AC_CONFIG_SUBDIRS may be called multiple times.
1360 * New macro AC_OUTPUT_COMMANDS adds more commands to run in config.status.
1363 Major changes in Autoconf 2.11:
1365 Released November 18th, 1996, by David J. MacKenzie
1367 * AC_PROG_CC and AC_PROG_CXX check whether the compiler works.
1368 They also default CFLAGS/CXXFLAGS to "-g -O2" for gcc, instead of "-g -O".
1369 * AC_REPLACE_FUNCS defines HAVE_foo if the system has the function `foo'.
1370 * AC_CONFIG_HEADER expands shell variables in its argument.
1371 * New macros: AC_FUNC_FNMATCH, AC_FUNC_SETPGRP.
1372 * The "checking..." messages and the source code for test programs that
1373 fail are saved in config.log.
1374 * Another workaround has been added for seds with small command length limits.
1375 * config.sub and config.guess recognize more system types.
1378 Major changes in Autoconf 2.10:
1380 Released May 7th, 1996, by Roland McGrath
1383 * The cache variable names used by `AC_CHECK_LIB(LIB, FUNC, ...)' has
1384 changed: now $ac_cv_lib_LIB_FUNC, previously $ac_cv_lib_LIB.
1386 Major changes in Autoconf 2.9:
1388 Released March 16th, 1996, by Roland McGrath
1392 Major changes in Autoconf 2.8:
1394 Released March 8th, 1996, by Roland McGrath
1398 Major changes in Autoconf 2.7:
1400 Released November 22nd, 1995, by David J. MacKenzie
1404 Major changes in Autoconf 2.6:
1406 Released November 20th, 1995, by David J. MacKenzie
1410 Major changes in Autoconf 2.5:
1412 Released November 17th, 1995, by Roland McGrath
1414 * New configure options --bindir, --libdir, --datadir, etc., with
1415 corresponding output variables.
1416 * New macro: AC_CACHE_CHECK, to make using the cache easier.
1417 * config.log contains the command being run as well as any output from it.
1418 * AC_CHECK_LIB can check for libraries with "." or "/" or "+" in their name.
1419 * AC_PROG_INSTALL doesn't cache a name for install-sh, for sharing caches.
1420 * AC_CHECK_PROG, AC_PATH_PROG, AC_CHECK_PROGS, AC_PATH_PROGS, and
1421 AC_CHECK_TOOL can search a path other than $PATH.
1422 * AC_CHECK_SIZEOF takes an optional size to use when cross-compiling.
1424 Major changes in Autoconf 2.4:
1426 Released June 14th, 1995, by David J. MacKenzie
1428 * Fix a few bugs found by Emacs testers.
1430 Major changes in Autoconf 2.3:
1432 Released March 27th, 1995, by David J. MacKenzie
1434 * Fix the cleanup trap in several ways.
1435 * Handle C compilers that are picky about option placement.
1436 * ifnames gets the version number from the right directory.
1438 Major changes in Autoconf 2.2:
1440 Released March 8th, 1995, by David J. MacKenzie
1442 * The ifnames utility is much faster but requires a "new awk" interpreter.
1443 * AC_CHECK_LIB and AC_HAVE_LIBRARY check and add the new
1444 library before existing libs, not after, in case it uses them.
1445 * New macros: AC_FUNC_GETPGRP, AC_CHECK_TOOL.
1446 * Lots of bug fixes.
1447 * Many additions to the TODO file :-)
1449 Major changes in Autoconf 2.1:
1451 Released November 4th, 1994, by David J. MacKenzie
1454 * More explanations in the manual.
1455 * Fix a spurious failure in the testsuite.
1456 * Clarify some warning messages.
1457 * autoreconf by default only rebuilds configure and config.h.in files
1458 that are older than any of their particular input files; there is a
1459 --force option to use after installing a new version of Autoconf.
1461 Thanks to everybody who's submitted changes and additions to Autoconf!
1462 I've incorporated many of them, and am still considering others for
1463 future releases -- but I didn't want to postpone this release indefinitely.
1465 Caution: don't indiscriminately rebuild configure scripts with
1466 Autoconf version 2. Some configure.in files need minor adjustments to
1467 work with it; the documentation has a chapter on upgrading. A few
1468 configure.in files, including those for GNU Emacs and the GNU C
1469 Library, need major changes because they relied on undocumented
1470 internals of version 1. Future releases of those packages will have
1471 updated configure.in files.
1473 It's best to use GNU M4 1.3 (or later) with Autoconf version 2.
1474 Autoconf now makes heavy use of M4 diversions, which were implemented
1475 inefficiently in GNU M4 releases before 1.3.
1477 Major changes in Autoconf 2.0:
1479 Released October 26th, 1994, by David J. MacKenzie
1481 ** New copyright terms:
1482 * There are no restrictions on distribution or use of configure scripts.
1485 * Autoconf manual is reorganized to make information easier to find
1486 and has several new indexes.
1487 * INSTALL is reorganized and clearer and is now made from Texinfo source.
1490 * autoscan to generate a preliminary configure.in for a package by
1491 scanning its source code for commonly used nonportable functions,
1492 programs, and header files.
1493 * ifnames to list the symbols used in #if and #ifdef directives in a
1495 * autoupdate to update a configure.in to use the version 2 macro names.
1496 * autoreconf to recursively remake configure and configuration header
1497 files in a source tree.
1499 ** Changed utilities:
1500 * autoheader can take pieces of acconfig.h to replace config.h.{top,bot}.
1501 * autoconf and autoheader can look for package-local definition files
1502 in an alternate directory.
1505 * AC_CACHE_VAL to share results of tests between configure runs.
1506 * AC_DEFUN to define macros, automatically AC_PROVIDE them, and ensure
1507 that macros invoked with AC_REQUIRE don't interrupt other macros.
1508 * AC_CONFIG_AUX_DIR, AC_CANONICAL_SYSTEM, AC_CANONICAL_HOST, AC_LINK_FILES to
1509 support deciding unguessable features based on the host and target types.
1510 * AC_CONFIG_SUBDIRS to recursively configure a source tree.
1511 * AC_ARG_PROGRAM to use the options --program-prefix,
1512 --program-suffix, and --program-transform-name to change the names
1513 of programs being installed.
1514 * AC_PREFIX_DEFAULT to change the default installation prefix.
1515 * AC_TRY_COMPILE to compile a test program without linking it.
1516 * AC_CHECK_TYPE to check whether sys/types.h or stdlib.h defines a given type.
1517 * AC_CHECK_LIB to check for a particular function and library.
1518 * AC_MSG_CHECKING and AC_MSG_RESULT to print test results, on a single line,
1519 whether or not the test succeeds. They obsolete AC_CHECKING and AC_VERBOSE.
1520 * AC_SUBST_FILE to insert one file into another.
1521 * AC_FUNC_MEMCMP to check whether memcmp is 8-bit clean.
1522 * AC_FUNC_STRFTIME to find strftime even if it's in -lintl.
1523 * AC_FUNC_GETMNTENT to find getmntent even if it's in -lsun or -lseq.
1524 * AC_HEADER_SYS_WAIT to check whether sys/wait.h is POSIX.1 compatible.
1527 * Many macros renamed systematically, but old names are accepted for
1528 backward compatibility.
1529 * AC_OUTPUT adds the "automatically generated" comment to
1530 non-Makefiles where it finds @configure_input@ in an input file, to
1531 support files with various comment syntaxes.
1532 * AC_OUTPUT does not replace "prefix" and "exec_prefix" in generated
1533 files when they are not enclosed in @ signs.
1534 * AC_OUTPUT allows the optional environment variable CONFIG_STATUS to
1535 override the file name "config.status".
1536 * AC_OUTPUT takes an optional argument for passing variables from
1537 configure to config.status.
1538 * AC_OUTPUT and AC_CONFIG_HEADER allow you to override the input-file names.
1539 * AC_OUTPUT automatically substitutes the values of CFLAGS, CXXFLAGS,
1540 CPPFLAGS, and LDFLAGS from the environment.
1541 * AC_PROG_CC and AC_PROG_CXX now set CFLAGS and CXXFLAGS, respectively.
1542 * AC_PROG_INSTALL looks for install-sh or install.sh in the directory
1543 specified by AC_CONFIG_AUXDIR, or srcdir or srcdir/.. or
1544 srcdir/../.. by default.
1545 * AC_DEFINE, AC_DEFINE_UNQUOTED, and AC_SUBST are more robust and smaller.
1546 * AC_DEFINE no longer prints anything, because of the new result reporting
1547 mechanism (AC_MSG_CHECKING and AC_MSG_RESULT).
1548 * AC_VERBOSE pays attention to --quiet/--silent, not --verbose.
1549 * AC_ARG_ENABLE and AC_ARG_WITH support whitespace in the arguments to
1550 --enable- and --with- options.
1551 * AC_CHECK_FUNCS and AC_CHECK_HEADERS take optional shell commands to
1552 execute on success or failure.
1553 * Checking for C functions in C++ works.
1556 * AC_REMOTE_TAPE and AC_RSH removed; too specific to tar and cpio, and
1557 better maintained with them.
1558 * AC_ARG_ARRAY removed because no one was likely using it.
1559 * AC_HAVE_POUNDBANG replaced with AC_SYS_INTERPRETER, which doesn't
1560 take arguments, for consistency with all of the other specific checks.
1563 * Comes with config.sub and config.guess, and uses them optionally.
1564 * Uses config.cache to cache test results. An alternate cache file
1565 can be selected with the --cache-file=FILE option.
1566 * Uses optional shell scripts $prefix/share/config.site and
1567 $prefix/etc/config.site to perform site or system specific initializations.
1568 * configure saves compiler output to ./config.log for debugging.
1569 * New files autoconf.m4 and autoheader.m4 load the other Autoconf macros.
1570 * acsite.m4 is the new name for the system-wide aclocal.m4.
1571 * Has a DejaGnu test suite.
1573 Major changes in Autoconf 1.11:
1575 * AC_PROG_INSTALL calls install.sh with the -c option.
1576 * AC_SET_MAKE cleans up after itself.
1577 * AC_OUTPUT sets prefix and exec_prefix if they weren't set already.
1578 * AC_OUTPUT prevents shells from looking in PATH for config.status.
1580 Plus a few other bug fixes.
1582 Major changes in Autoconf 1.10:
1584 * autoheader uses config.h.bot if present, analogous to config.h.top.
1585 * AC_PROG_INSTALL looks for install.sh in srcdir or srcdir/.. and
1587 * AC_PROG_CXX looks for cxx as a C++ compiler.
1589 Plus several bugs fixed.
1591 Major changes in Autoconf 1.9:
1593 * AC_YYTEXT_POINTER replaces AC_DECLARE_YYTEXT.
1594 * AC_SIZEOF_TYPE generates the cpp symbol name automatically,
1595 and autoheader generates entries for those names automatically.
1596 * AC_FIND_X gets the result from xmkmf correctly.
1597 * AC_FIND_X assumes no X if --without-x was given.
1598 * AC_FIND_XTRA adds libraries to the variable X_EXTRA_LIBS.
1599 * AC_PROG_INSTALL finds OSF/1 installbsd.
1601 Major changes in Autoconf 1.8:
1604 * New macros AC_LANG_C, AC_LANG_CPLUSPLUS, AC_LANG_SAVE, AC_LANG_RESTORE,
1605 AC_PROG_CXX, AC_PROG_CXXCPP, AC_REQUIRE_CPP
1606 for checking both C++ and C features in one configure script.
1607 * New macros AC_CHECKING, AC_VERBOSE, AC_WARN, AC_ERROR for printing messages.
1608 * New macros AC_FIND_XTRA, AC_MMAP, AC_SIZEOF_TYPE, AC_PREREQ,
1609 AC_SET_MAKE, AC_ENABLE.
1612 * AC_FIND_X looks for X in more places.
1613 * AC_PROG_INSTALL defaults to install.sh instead of cp, if it's in srcdir.
1614 install.sh is distributed with Autoconf.
1615 * AC_DECLARE_YYTEXT has been removed because it can't work, pending
1616 a rewrite of quoting in AC_DEFINE.
1617 * AC_OUTPUT adds its comments in C format when substituting in C files.
1618 * AC_COMPILE_CHECK protects its ECHO-TEXT argument with double quotes.
1620 ** New or changed command line options:
1621 * configure accepts --enable-FEATURE[=ARG] and --disable-FEATURE options.
1622 * configure accepts --without-PACKAGE, which sets withval=no.
1623 * configure accepts --x-includes=DIR and --x-libraries=DIR.
1624 * Giving --with-PACKAGE no argument sets withval=yes instead of withval=1.
1625 * configure accepts --help, --version, --silent/--quiet, --no-create options.
1626 * configure accepts and ignores most other Cygnus configure options, and
1627 warns about unknown options.
1628 * config.status accepts --help, --version options.
1630 ** File names and other changes:
1631 * Relative srcdir values are not made absolute.
1632 * The values of @prefix@ and @exec_prefix@ and @top_srcdir@ get substituted.
1633 * Autoconf library files are installed in ${datadir}/autoconf, not ${datadir}.
1634 * autoheader optionally copies config.h.top to the beginning of config.h.in.
1635 * The example Makefile dependencies for configure et al. work better.
1636 * Namespace cleanup: all shell variables used internally by Autoconf
1637 have names beginning with `ac_'.
1639 More big improvements are in process for future releases, but have not
1640 yet been (variously) finished, integrated, tested, or documented enough
1643 Major changes in Autoconf 1.7:
1645 * New macro AC_OBSOLETE.
1646 * Bugs in Makefile.in fixed.
1647 * AC_LONG_FILE_NAMES improved.
1649 Major changes in Autoconf 1.6:
1651 * New macro AC_LONG_64_BITS.
1652 * Multiple .h files can be created.
1653 * AC_FIND_X looks for X files directly if it doesn't find xmkmf.
1654 * AC_ALLOCA defines C_ALLOCA if using alloca.c.
1655 * --with-NAME can take a value, e.g., --with-targets=sun4,hp300bsd.
1656 * Unused --no-create option to configure removed.
1657 * autoheader doesn't change the timestamp of its output file if
1658 the file didn't change.
1659 * All macros that look for libraries now use AC_HAVE_LIBRARY.
1660 * config.status checks three optional environment variables to
1661 modify its behavior.
1662 * The usual bug fixes.
1664 Major changes in Autoconf 1.5:
1666 * New macros AC_FIND_X, AC_OFF_T, AC_STAT_MACROS_BROKEN, AC_REVISION.
1667 * autoconf and autoheader scripts have GNU standards conforming
1668 --version and --help options (they print their message and exit).
1671 Major changes in Autoconf 1.4:
1673 * New macros AC_HAVE_POUNDBANG, AC_TIME_WITH_SYS_TIME, AC_LONG_DOUBLE,
1674 AC_GETGROUPS_T, AC_DEFINE_UNQUOTED.
1675 * autoconf and autoheader use the M4 environment variable to determine the
1676 name of the M4 program to use.
1677 * The --macrodir option to autoconf and autoheader specifies the directory
1678 in which acspecific.m4, acgeneral.m4, etc. reside if not the default.
1679 * autoconf and autoheader can take `-' as their file names, which means to
1680 read stdin as input.
1681 * Resulting configure scripts can take a --verbose option which causes them
1682 to print the results of their tests.
1683 * AC_DEFINE quotes its second argument in such a way that spaces, magic
1684 shell characters, etc. will be preserved during various stages of
1685 expansion done by the shell. If you don't want this, use
1686 AC_DEFINE_UNQUOTED instead.
1687 * Much textual processing done with external calls to tr and sed have been
1688 internalized with builtin M4 `patsubst' and `translit' calls.
1689 * AC_OUTPUT doesn't hardwire the file names it outputs. Instead, you can
1690 set the shell variables `gen_files' and `gen_config' to the list of
1691 file names to output.
1692 * AC_DECLARE_YYTEXT does an AC_SUBST of `LEX_OUTPUT_ROOT', which may be
1693 "lex.yy" or "lexyy", depending on the system.
1694 * AC_PROGRAMS_CHECK takes an optional third arg. If given, it is used as
1696 * If AC_ALLOCA chooses alloca.c, it also defines STACK_DIRECTION.
1697 * AC_CONST works much more reliably on more systems.
1700 Major changes in Autoconf 1.3:
1702 configure no longer requires awk for packages that use a config.h.
1703 Support handling --with-PACKAGE options.
1704 New `autoheader' script to create `config.h.in' from `configure.in'.
1705 Ignore troublesome -lucb and -lPW when searching for alloca.
1706 Rename --exec_prefix to --exec-prefix for GNU standards conformance.
1707 Improve detection of STDC library.
1708 Add AC_HAVE_LIBRARY to check for non-default libraries.
1709 Function checking should work with future GNU libc releases.
1711 Major changes in Autoconf 1.2:
1713 The --srcdir option is now usually unnecessary.
1714 Add a file containing sample comments describing CPP macros.
1715 A comment in config.status tells which host it was configured on.
1716 Substituted variable values can now contain commas.
1717 Fix bugs in various feature checks.
1719 Major changes in Autoconf 1.1:
1721 Added AC_STRCOLL macro.
1722 Made AC_GETLOADAVG check for more things.
1723 AC_OUTPUT argument is now optional.
1728 Copyright (C) 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002,
1729 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
1731 This program is free software: you can redistribute it and/or modify
1732 it under the terms of the GNU General Public License as published by
1733 the Free Software Foundation, either version 3 of the License, or
1734 (at your option) any later version.
1736 This program is distributed in the hope that it will be useful,
1737 but WITHOUT ANY WARRANTY; without even the implied warranty of
1738 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1739 GNU General Public License for more details.
1741 You should have received a copy of the GNU General Public License
1742 along with this program. If not, see <http://www.gnu.org/licenses/>.