1 GNU Autoconf NEWS - User visible changes.
3 * Major changes in Autoconf 2.63 (2008-09-09) [stable]
4 Released by Eric Blake, based on git versions 2.62.*.
6 ** AC_C_BIGENDIAN does not mistakenly report "universal" for some
7 bigendian hosts, a regression introduced with universal binary
10 ** AC_PATH_X now includes /lib64 and /usr/lib64 in its list of default
13 ** AC_USE_SYSTEM_EXTENSIONS no longer conflicts with an external
14 AC_DEFINE([__EXTENSIONS__]). This fixes a regression introduced in
15 2.62 when using macros such as AC_AIX that were made obsolete in
16 favor of the more portable AC_USE_SYSTEM_EXTENSIONS.
18 ** AC_CHECK_TARGET_TOOLS is usable in the non-cross-compile case.
20 ** Newly obsolete macros
21 The following macro has been marked obsolete, since current porting
22 targets can safely assume C89 semantics that signal handlers return
23 void. We have no current plans to remove the macro.
27 ** The macros m4_map and m4_map_sep now ignore any list elements
28 consisting of just empty quotes, and m4_map_sep now expands its
29 separator. This fixes a regression in 2.62 when these macros were
30 first documented, for the sake of clients expecting the semantics
31 that these macros had prior to that time. The new macros m4_mapall
32 and m4_mapall_sep, along with extra quoting of the separator, can
33 be used to get the semantics that m4_map_sep had in 2.62.
35 ** Clients of m4_expand, such as AS_HELP_STRING and AT_SETUP, can now
36 handle properly quoted but otherwise unbalanced parentheses (for
37 some macros, this fixes a regression in 2.62).
39 ** Two new quadrigraphs have been introduced: @{:@ for (, and @:}@ for ),
40 allowing the output of unbalanced parentheses in more contexts.
42 ** The following m4sugar macros are new:
43 m4_joinall m4_mapall m4_mapall_sep m4_reverse m4_set_add
44 m4_set_add_all m4_set_contains m4_set_contents m4_set_delete
45 m4_set_difference m4_set_dump m4_set_empty m4_set_foreach
46 m4_set_intersection m4_set_list m4_set_listc m4_set_remove
47 m4_set_size m4_set_union
49 ** The following m4sugar macros now accept multiple arguments, as is the
50 case with underlying m4:
51 m4_defn m4_popdef m4_undefine
53 ** The following m4sugar macros now guarantee linear scaling; they
54 previously had linear scaling with m4 1.6 but quadratic scaling
55 when using m4 1.4.x. All macros built on top of these also gain
56 the scaling improvements.
57 m4_bmatch m4_bpatsubsts m4_case m4_cond m4_do m4_dquote_elt
58 m4_foreach m4_join m4_list_cmp m4_map m4_map_sep m4_max
61 ** AT_KEYWORDS once again performs expansion on its argument, such that
62 AT_KEYWORDS([m4_if([$1], [], [default])]) no longer complains about
63 the possibly unexpanded m4_if [regression introduced in 2.62].
65 ** Config header templates `#undef UNDEFINED /* comment */' do not lead to
66 nested comments any more; regression introduced in 2.62.
69 * Major changes in Autoconf 2.62 (2008-04-05) [stable]
70 Released by Eric Blake, based on git versions 2.61a.*.
72 ** Many optimizations have been applied to make overall execution faster.
74 ** Autotest now makes use of shell functions.
76 ** config.status now uses awk instead of sed also for config headers.
78 - As a side effect, AC_DEFINE and AC_DEFINE_UNQUOTED now handle multi-line
79 values, i.e., backslash-newline combinations are handled correctly.
80 Further, for config headers, the total size of values is not limited by
81 the POSIX length limit of text lines any more, only each single line.
83 ** New config variable `top_build_prefix'.
85 ** New Autoconf macros:
86 AC_AUTOCONF_VERSION AC_OPENMP AC_PATH_PROGS_FEATURE_CHECK
88 ** AC_C_BIGENDIAN now supports universal binaries a la Mac OS X.
90 ** AC_C_RESTRICT now prefers to #define 'restrict' to a variant spelling
91 like '__restrict' if the variant spelling is available, as this is
92 more likely to work when mixing C and C++ code.
94 ** AC_CHECK_ALIGNOF's type argument T is now documented better: it must
95 be a string of tokens such that "T y;" is a valid member declaration
98 ** AC_CHECK_SIZEOF now accepts objects as well as types: the general rule
99 is that sizeof (X) works, then AC_CHECK_SIZEOF (X) should work.
101 ** AC_CHECK_TYPE and AC_CHECK_TYPES now work on any C type-name; formerly,
102 they did not work for function types. In C++, they now work on any
103 type-id that can be the operand of sizeof; this is similar to C,
104 except it excludes anonymous struct and union types. Formerly,
105 some (but not all) C++ types involving anonymous struct and union
106 were accepted, though this was not documented.
108 ** AC_CONFIG_LINKS now prefers to link against files in the build tree
109 if found, and it works to link against a file of the same name in
110 the source tree, even if both trees coincide.
112 ** AC_INIT no longer alters $@; regression introduced in 2.60.
114 ** AC_USE_SYSTEM_EXTENSIONS now defines _ALL_SOURCE for Interix platforms.
116 ** AS_HELP_STRING no longer underquotes its first argument; it also handles
117 the case where the first argument contains single-quoted commas.
118 For example, "AS_HELP_STRING([-a, [--arg[=foo]]], [bar])" produces:
119 " -a, --arg[=foo] bar"
120 Additionally, the macro now takes two additional arguments,
121 indent-column and wrap-column; these should not normally be needed,
122 but can be used to fine-tune how the output text is wrapped.
124 ** AC_PROG_INSTALL now requires an install program that can install multiple
125 files into a target directory.
127 ** The command 'autoconf -' now correctly processes a file from stdin.
129 ** 'autoreconf -m' now honors $MAKE.
131 ** For all of the directory arguments for 'configure', such as '--prefix'
132 or '--bindir', trailing slashes are stripped. As an example, if
133 tab completion in the user's shell appends trailing slashes, the
134 command './configure --prefix=/usr/' will still result in an
135 expanded libdir value of /usr/lib, not /usr//lib.
137 ** `configure --help=recursive' now works in read-only trees and from
138 unconfigured build trees.
140 ** If precious variables differ only in whitespace, then the cache consistency
141 check warns instead of fails, and reuses the old value.
143 ** AT_BANNER is now documented.
145 ** AT_SETUP now handles macro expansions properly when calculating line
148 ** Autotest now determines $srcdir correctly.
150 ** Testsuites built by autotest now accept a -C/--directory=DIR option
151 to adjust the working directory prior to creating files.
153 ** Autoconf now requires GNU M4 1.4.5 or later. Earlier versions of M4 have
154 a bug in macro tracing that interferes with the interaction between
155 Autoconf and Automake. GNU M4 1.4.11 or later is recommended. The
156 configure search for a working M4 is improved.
158 ** For portability with the eventual M4 2.0, macros should no longer use
159 anything larger than $9 to refer to arguments.
161 ** Documentation for m4sugar is improved.
163 - The following macros were previously available as undocumented
164 interfaces; the macros are now documented as stable interfaces.
166 __oline__ m4_assert m4_bmatch m4_bpatsubsts m4_car m4_case
167 m4_cdr m4_default m4_divert_once m4_divert_pop m4_divert_push
168 m4_divert_text m4_do m4_errprintn m4_fatal m4_flatten
169 m4_ifndef m4_ifset m4_ifval m4_ifvaln m4_location
170 m4_n m4_shiftn m4_strip m4_warn
172 - The following macros were previously available as undocumented
173 interfaces, but had bug fixes or semantic changes as part of this
174 release. Packages that relied on the undocumented behavior
175 should be analyzed to make sure they will still work with the
176 new documented behavior.
178 m4_cmp m4_list_cmp m4_join m4_map m4_map_sep m4_sign
179 m4_text_box m4_text_wrap m4_version_compare
181 - The m4_wrap macro used to have unspecified order, but now
182 guarantees FIFO order. m4_wrap_lifo was added to guarantee LIFO
185 - Packages using the undocumented m4sugar macro m4_PACKAGE_VERSION
186 should consider using the new AC_AUTOCONF_VERSION instead.
188 - m4sugar macros that are not documented in the manual are still
189 deemed experimental, and should not be used outside of Autoconf.
191 ** The m4sugar macros m4_append and m4_append_uniq, first documented in
192 2.60, have been fixed to treat both the string and the separator
193 arguments consistently with regards to quoting. Prior to this fix,
194 m4_append_uniq could mistakenly duplicate entries if the expansion
195 of the separator resulted in a different string (for example, if it
196 contained quotes, a comma, or a macro name). However, it means
197 that programs previously using
198 m4_append([name], [string], [[, ]])
199 are now using a four-character separator instead of the intended
200 comma and space. If you need portability to earlier versions of
201 Autoconf, you can insert the following snippet after AC_INIT but
202 before any other macro expansions, to enforce the new semantics:
203 m4_pushdef([m4_append], [m4_define([$1],
204 m4_ifdef([$1], [m4_defn([$1])[$3]])[$2])])
205 Additionally, m4_append_uniq now takes optional parameters that can
206 be used to take action depending on whether anything was appended,
207 and warns if a non-empty separator occurs within the string being
208 appended, since that can lead to duplicates.
210 ** The following m4sugar macros are new:
211 m4_append_uniq_w m4_apply m4_combine m4_cond m4_count
212 m4_dquote_elt m4_echo m4_expand m4_ignore m4_make_list m4_max
213 m4_min m4_newline m4_shift2 m4_shift3 m4_unquote m4_wrap_lifo
215 ** Warnings are now generated by default when an installer invokes
216 'configure' with an unknown --enable-* or --with-* option.
217 These warnings can be disabled with the new AC_DISABLE_OPTION_CHECKING
218 macro, or by invoking 'configure' with --disable-option-checking.
220 ** Existing obsolete macros
221 The documentation for the following macros is adjusted to make it
222 more clear that they have previously been marked obsolete, as their
223 functionality can be accomplished by other macros. We have no
224 current plans to remove them from Autoconf.
226 AC_ENABLE AC_STRUCT_ST_BLKSIZE AC_STRUCT_ST_RDEV AC_WITH
228 ** Newly obsolete macros
229 The following macros have been marked obsolete, as they only
230 perform a subset of AC_USE_SYSTEM_EXTENSIONS. We have no current
231 plans to remove them.
233 AC_AIX AC_GNU_SOURCE AC_ISC_POSIX AC_MINIX
235 ** AC_C_LONG_DOUBLE is obsolescent.
236 The documentation now says that AC_C_LONG_DOUBLE is obsolescent: it
237 tests for problems that are so old that it is no longer of
238 practical importance on current systems. New programs need not use
239 AC_C_LONG_DOUBLE. We have no current plans to remove it.
241 ** AC_DIAGNOSE, AC_WARNING, and AC_FATAL are obsolescent.
242 The documentation now favors the use of M4sugar macros m4_warn and
243 m4_fatal, since the naming makes it more obvious that the
244 diagnostics are associated with M4 expansion (ie. when running
245 `autoconf'), and offers less confusion with the AC_MSG_ERROR,
246 AC_MSG_FAILURE, and AC_MSG_WARN macros which manage diagnostics
247 when running `configure'. We have no current plans to remove these
251 * Major changes in Autoconf 2.61a (2006-12-11)
253 ** AC_FUNC_FSEEKO was broken in 2.61; it didn't make fseeko and ftello visible
254 on many platforms. This has been fixed.
256 ** AC_FUNC_SETVBUF_REVERSED is now obsolete. It is still defined for backward
257 compatibility but it does nothing. The macro was already
258 obsolescent, as the last systems to have the problem were those
259 based on SVR2, which became obsolete in 1987. The macro had bugs
260 on some modern systems and could no longer be maintained reliably
261 due to lack of ancient systems to test it on.
263 ** config.status now uses awk instead of sed for most substitutions, for speed.
265 - As a side effect multi-line values of substituted variables no
266 longer have a small limit in total size, though for portability
267 each line should not exceed the POSIX length limit for text lines.
269 - It is now documented that Makefile.in should not contain
270 overlapping variable occurrences, e.g., @VAR1@VAR2@.
271 Autoconf's behavior was always iffy in such cases, and the
272 awk implementation has changed the behavior.
274 ** Many uses of 'echo' have been rewritten so that Autoconf-generated
275 scripts have fewer problems with strings or file names containing
276 embedded special characters such as backslash or leading "-". This
277 was implemented by using `printf '%s\n' "$foo"' instead of `echo
278 "$foo"' when printf works. Due to the implementation technique
279 used, Autoconf-generated scripts now run considerably more slowly
280 on ancient implementations lacking printf. However, this should
281 not be a problem, since Autoconf-generated scripts in practice
282 invariably find a more-modern shell these days.
285 * Major changes in Autoconf 2.61 (2006-11-17)
287 ** New macros AC_C_FLEXIBLE_ARRAY_MEMBER, AC_C_VARARRAYS.
289 ** AC_ARG_ENABLE and AC_ARG_WITH now allow '.' in feature and package names.
292 * Major changes in Autoconf 2.60b (2006-10-22)
295 Autoconf-generated shell scripts no longer export BIN_SH, due to
296 configuration hassles with this. Installers who need BIN_SH in
297 their environment should set it before invoking 'configure' and
298 'make'. As far as we know, this affects only Unixware installations.
300 ** Obsolescent macros
301 The documentation now says that the following macros are obsolescent,
302 as they are superseded by Gnulib:
304 AC_FUNC_FNMATCH AC_FUNC_FNMATCH_GNU AC_FUNC_GETLOADVG AC_REPLACE_FNMATCH
306 New programs should use the Gnulib counterparts of these macros.
307 We have no current plans to remove them from Autoconf.
309 ** AC_COMPUTE_INT no longer caches or reports results.
311 ** AC_CHECK_DECL now also works with aggregate objects.
313 ** AC_USE_SYSTEM_EXTENSIONS now defines _TANDEM_SOURCE for NonStop platforms.
315 ** GNU M4 1.4.7 or later is now recommended.
318 New M4sugar macro, which is more secure than the POSIX M4 maketemp.
321 Now an alias for m4_mkstemp.
323 * Major changes in Autoconf 2.60a (2006-08-25)
325 ** GNU M4 1.4.6 or later is now recommended.
327 ** The check for C99 now tests for varargs macros, as documented.
328 It also tests that the preprocessor supports 64-bit integers.
330 ** Autoconf now uses constructs like "#ifdef HAVE_STDLIB_H" rather than
331 "#if HAVE_STDLIB_H", so that it now works with "gcc -Wundef -Werror".
333 ** The functionality of the undocumented _AC_COMPUTE_INT is now provided
334 by a public and documented macro, AC_COMPUTE_INT. The parameters to the
335 two macros are different, so autoupdate will not change the old private name
336 to the new one. _AC_COMPUTE_INT may be removed in a future release.
338 ** AC_TYPE_LONG_LONG_INT and AC_TYPE_UNSIGNED_LONG_LONG_INT now require
339 that long long types be at least 64 bits wide, as C99 and tradition
340 requires. Formerly, they accepted implementations of any width.
343 * Major changes in Autoconf 2.60
345 Released 2006-06-23, by Ralf Wildenhues.
347 ** Autoconf no longer depends on whether m4wrap is FIFO (as Posix requires)
348 or LIFO (as in GNU M4 1.4.x). GNU M4 2.0 is expected to conform to Posix
349 here, so m4wrap/m4_wrap users should no longer depend on LIFO behavior.
351 ** Provide a way to turn off warnings about the changed directory variables.
353 * Major changes in Autoconf 2.59d
355 Released 2006-06-05, by Ralf Wildenhues.
357 ** GNU make now recommended for VPATH builds
358 INSTALL now suggests VPATH builds (e.g., "sh ../srcdir/configure")
359 only if you use GNU make. In practice, other 'make' implementations
360 have too many subtle incompatibilities in their support for VPATH.
361 Many packages (including Autoconf itself) are portable to other
362 'make' implementations, but some packages are not, and recommending
363 GNU make keeps the installation instructions simpler.
365 ** Even more safety checks for the new Directory variables:
366 Warn about suspicious `${datarootdir}' found in config files output.
368 ** AC_TRY_COMMAND, AC_TRY_EVAL, ac_config_guess, ac_config_sub, ac_configure
369 These never-documented macros and variables have been marked with
370 comments saying that they may be removed in a future release,
371 because their use can lead to unintended code being executed.
372 If you need functionality that only these macros or variables
373 currently supply, please write bug-autoconf@gnu.org.
375 ** AC_SUBST, AC_DEFINE
376 Literal arguments to these are passed to m4_pattern_allow now.
379 Passing 'ac_cv_prog_cc_stdc=no' to 'configure' now sets ac_cv_prog_cc_c99
380 and ac_cv_prog_cc_c89 to 'no' as well, for backward compatibility with
381 obsolete K&R tests in the Automake test suite.
390 Now more robust with special characters in file names, or when
391 multiple processes create the same directory at the same time.
393 ** Obsolescent macros
394 The documentation now says that the following macros are obsolescent:
395 they test for problems that are so old that they are no longer of
396 practical importance on current systems.
398 AC_C_BACKSLASH_A AC_FUNC_MEMCMP AC_HEADER_DIRENT
399 AC_C_CONST AC_FUNC_SELECT_ARGTYPES AC_HEADER_STAT
400 AC_C_PROTOTYPES AC_FUNC_SETPGRP AC_HEADER_STDC
401 AC_C_STRINGIZE AC_FUNC_SETVBUF_REVERSED AC_HEADER_SYS_WAIT
402 AC_C_VOLATILE AC_FUNC_STAT AC_HEADER_TIME
403 AC_FUNC_CLOSEDIR_VOID AC_FUNC_STRFTIME AC_ISC_POSIX
404 AC_FUNC_GETPGRP AC_FUNC_UTIME_NULL AC_PROG_GCC_TRADITIONAL
405 AC_FUNC_LSTAT AC_FUNC_VPRINTF AC_STRUCT_TM
407 New programs need not use these macros. We have no current plans to
411 For compatibility with future Libtool 2.0, autoreconf will invoke
412 libtoolize with the option `--ltdl' now, if LT_CONFIG_LTDL_DIR is
415 * Major changes in Autoconf 2.59c
417 Released 2006-04-12, by Ralf Wildenhues.
419 ** The configure command now redirects standard input from /dev/null,
420 to help avoid problems with subsidiary commands that might mistakenly
421 read standard input. AS_ORIGINAL_STDIN_FD points to the original
422 standard input before this redirection, if you really want configure to
423 read from standard input.
425 ** Directory variables adjusted to recent changes in the GNU Coding Standards.
426 The following directory variables are new:
428 datarootdir read-only architecture-independent data root [PREFIX/share]
429 localedir locale-specific message catalogs [DATAROOTDIR/locale]
430 docdir documentation root [DATAROOTDIR/doc/PACKAGE]
431 htmldir html documentation [DOCDIR]
432 dvidir dvi documentation [DOCDIR]
433 pdfdir pdf documentation [DOCDIR]
434 psdir ps documentation [DOCDIR]
436 The following variables have new default values:
438 datadir read-only architecture-independent data [DATAROOTDIR]
439 infodir info documentation [DATAROOTDIR/info]
440 mandir man documentation [DATAROOTDIR/man]
442 This means that if you use any of `@datadir@', `@infodir@', or
443 `@mandir@' in a file, you will have to ensure `${datarootdir}' is
444 defined in this file. As a temporary measure, if any of those are
445 found but no mention of `datarootdir', the substitutions will be
446 replaced with values that do not contain `${datarootdir}', and a
447 warning will be issued.
449 ** @top_builddir@ is now a dir name: it is always nonempty and doesn't have
450 a trailing slash. Similar change will be made to ac_top_builddir in a
451 future release; the old style value, which matches (../)*, is (and will
452 continue to be) available as ac_top_build_prefix.
455 New macro to check for support of 'typeof' syntax a la GNU C.
457 ** AC_CHECK_DECLS_ONCE, AC_CHECK_FUNCS_ONCE, AC_CHECK_HEADERS_ONCE
458 New "once-only" variants of commonly-used macros, to make 'configure'
459 smaller and faster in common cases.
462 New macro to check for strtold with C99 semantics.
465 New macro that lets builder disable assertions at 'configure'-time.
468 Now checks for X11/Xlib.h and XrmInitialize (X proper) rather than
469 X11/Intrinsic.h and XtMalloc (Xt).
471 ** AC_PRESERVE_HELP_ORDER
472 New macro that causes `configure' to display help strings for AC_ARG_ENABLE
473 and AC_ARG_WITH arguments in one region, in the order defined. The default
474 behavior is to group options of each classes separately.
476 ** AC_PROG_CC, AC_PROG_CXX
477 No longer automatically arrange to declare the 'exit' function of C,
478 when a C++ compiler is used. Standard Autoconf macros no longer use
479 'exit', so this is no longer an issue for them. If you use C++, and
480 want to call 'exit', you'll have to arrange for its declaration
481 yourself. But we now suggest you return from 'main' instead.
483 ** AC_PROG_CC_C89, AC_PROG_CC_C99
484 New macros for ISO C99 support. AC_PROG_CC_C89 and AC_PROG_CC_C99
485 check for ANSI C89 and ISO C99 support respectively.
488 Has been unobsoleted, and will check if the compiler supports ISO
489 C99, falling back to ANSI C89 if not. ac_cv_prog_cc_stdc is
490 retained for backwards compatibility, assuming the value of
491 ac_cv_prog_cc_c99 or ac_cv_prog_cc_c89 (whichever is valid, in
494 ** AC_STRUCT_DIRENT_D_INO, AC_STRUCT_DIRENT_D_TYPE
495 New macros for checking commonly-used members of struct dirent.
498 The substituted value can now contain newlines.
501 The substitution now occurs only when @variable@ is on a line by itself,
502 optionally surrounded by spaces and tabs. The whole line is replaced.
504 ** AC_TYPE_LONG_DOUBLE, AC_TYPE_LONG_DOUBLE_WIDER
505 New macros to check for long double, and whether it is wider than double.
506 The old macro AC_C_TYPE_LONG_DOUBLE has been marked as obsolete;
507 applications should switch to the new macro.
509 ** AC_TYPE_INT8_T, AC_TYPE_INT16_T, AC_TYPE_INT32_T, AC_TYPE_INT64_T,
510 AC_TYPE_INTMAX_T, AC_TYPE_INTPTR_T, AC_TYPE_LONG_LONG_INT, AC_TYPE_SSIZE_T,
511 AC_TYPE_UINT8_T, AC_TYPE_UINT16_T, AC_TYPE_UINT32_T, AC_TYPE_UINT64_T,
512 AC_TYPE_UINTMAX_T, AC_TYPE_UINTPTR_T, AC_TYPE_UNSIGNED_LONG_LONG_INT
513 New macros to check for C99 and POSIX types.
515 ** AC_USE_SYSTEM_EXTENSIONS
516 New macro to enable extensions to Posix.
519 New macro which is defined to the name of the first declared config header
520 or undefined if no config headers have been declared yet.
523 The macro correctly handles quadrigraphs now.
525 ** AS_BOURNE_COMPATIBLE, AS_SHELL_SANITIZE, AS_CASE
526 These macros are new or published now.
529 New macro for copyright notices in testsuite files.
531 ** ALLOCA, LIBOBJS, LTLIBOBJS
532 Object names added to these variables are now prefixed with `${LIBOBJDIR}',
533 as in `${LIBOBJDIR}alloca.o'. LIBOBJDIR is meant to be defined from
534 `Makefile.in' in case the object files lie in a different directory.
535 The LIBOBJDIR feature is experimental.
538 Supports --no-recursive now.
540 ** New macros to support Erlang/OTP.
541 New macros for configuring paths to Erlang tools and libraries:
542 AC_ERLANG_PATH_ERLC, AC_ERLANG_NEED_ERLC, AC_ERLANG_PATH_ERL,
543 AC_ERLANG_NEED_ERL, AC_ERLANG_CHECK_LIB, AC_ERLANG_SUBST_ROOT_DIR,
544 AC_ERLANG_SUBST_LIB_DIR.
546 New macros for configuring installation of Erlang libraries:
547 AC_ERLANG_SUBST_INSTALL_LIB_DIR, AC_ERLANG_SUBST_INSTALL_LIB_SUBDIR.
549 ** The manual now mentions Gnulib more prominently.
551 ** New macros to support Objective C.
552 AC_PROG_OBJC, AC_PROG_OBJCPP.
554 * Major changes in Autoconf 2.59b
556 Released 2004-08-20, by Paul Eggert.
559 New macro that computes the default alignment of a type.
561 ** AC_CHECK_TOOL, AC_PATH_TOOL, AC_CHECK_TOOLS
562 When cross-compiling, these macros will give a warning if the tool
563 is not prefixed. In the future, unprefixed cross tools will not
564 be detected; please consult the info documentation for information
565 about the reason of this change.
567 ** AC_CHECK_TARGET_TOOL, AC_PATH_TARGET_TOOL, AC_CHECK_TARGET_TOOLS
568 New macros that detect programs whose name is prefixed with the
569 target type, if the build type and target type are different.
571 ** AC_REQUIRE_AUX_FILE
572 New trace macro that declares expected auxiliary files.
575 New macro that tests for a grep program that accepts as a long a line
578 ** AC_PROG_EGREP, AC_PROG_FGREP
579 These macros now require AC_PROG_GREP, and try EGREP="$GREP -E" and
580 FGREP="$GREP -F" respectively if possible, or else run a path search for
581 a program that accepts as long a line as possible.
584 New macro that tests for a sed program that truncates as few characters
587 * Major changes in Autoconf 2.59
589 Released 2003-11-04, by Akim Demaille
591 ** ac_abs_builddir etc.
592 Absolute file names were actually relative in 2.58.
594 * Major changes in Autoconf 2.58
596 Released 2003-11-04, by Akim Demaille
599 core.* files are no longer removed, as they may be valid user files.
601 ** autoreconf and auxiliary directory
602 Autoreconf creates the auxiliary directory if needed. This is
603 especially useful for initial "bootstrapping" of fresh CVS checkouts.
605 ** AC_CONFIG_MACRO_DIR
606 Use this macro to declare the directory for local M4 macros for aclocal.
609 No longer includes twice the same file in LIBOBJS if invoked
612 ** AC_CONFIG_COMMANDS
613 The directory for its first argument is automatically created. For
616 AC_CONFIG_COMMANDS([src/modules.hh], [...])
618 $top_builddir/src/ is created if needed.
620 ** Autotest and local.at
621 The optional file local.at is always included in Autotest test suites.
624 The warnings are always issued, including with cached runs.
625 This became a significant problem since aclocal and automake can
626 run autoconf behind the scene.
628 ** autoheader warnings
629 The warnings of autoheader can be turned off, using --warning.
630 For instance, -Wno-obsolete disables the complaints about acconfig.h
631 and other deprecated constructs.
634 AC_C_RESTRICT, AC_INCLUDES_DEFAULT, AC_LANG_ASSERT, AC_LANG_WERROR,
637 ** AC_DECL_SYS_SIGLIST
641 Now checks that mktime is the inverse of localtime.
643 ** Improve DJGPP portability
644 The Autoconf tools and configure behave better under DJGPP.
646 ** Present But Cannot Be Compiled
647 New FAQ section dedicated to the mystic
649 configure: WARNING: pi.h: present but cannot be compiled
650 configure: WARNING: pi.h: check for missing prerequisite headers?
651 configure: WARNING: pi.h: proceeding with the preprocessor's result
654 ** Concurrent executions of autom4te
655 autom4te now locks its internal files, which enables concurrent
656 executions of autom4te, likely to happen if automake, autoconf,
657 autoheader etc. are run simultaneously.
660 Use of Libtool 1.5 and higher is encouraged. Compatibility with
661 Libtool pre-1.4 is not checked.
664 Testsuites no longer rerun failed tests in verbose mode; instead,
665 failures are logged while the test is run.
667 In addition, expected failures can be marked as such.
669 * Major changes in Autoconf 2.57
671 Released 2002-12-03 by Paul Eggert.
673 Bug fixes for problems with AIX linker, with freestanding C compilers,
674 with GNU M4 limitations, and with obsolete copies of GNU documents.
676 The Free Documentation License has been upgraded from 1.1 to 1.2.
678 * Major changes in Autoconf 2.56
680 Released 2002-11-15 by Akim Demaille.
682 One packaging problem fixed (config/install-sh was not executable).
684 * Major changes in Autoconf 2.55
686 Released 2002-11-14 by Akim Demaille.
690 Have your configure.ac checked by autoscan ("autoscan").
691 Try the warning options ("autoreconf -fv -Wall").
695 - AC_CHECK_HEADER, AC_CHECK_HEADERS
696 More information on proper use.
698 - Writing Test Programs
700 This sections explains how to write good test sources to use with
701 AC_COMPILE_IFELSE etc. It documents AC_LANG_PROGRAM and so forth.
703 - AC_FOO_IFELSE vs. AC_TRY_FOO
705 Explains why Autoconf moves from AC_TRY_COMPILE etc. to
706 AC_COMPILE_IFELSE and AC_LANG_PROGRAM etc.
710 - Is more robust to different Gettext installations.
712 - Produces messages (when --verbose) to be understood by Emacs'
715 - Supports -W/--warnings.
718 Once the GNU Build System reinstalled, run `./config.status
719 --recheck && ./config.status && make' if possible.
723 - Supports --cache, and --no-cache.
725 - ~/.autom4te.cfg makes it possible to disable the caching mechanism
726 (autom4te.cache). See `Customizing autom4te' in the documentation.
733 Support for the obsoleted options -m, --macrodir, -l, --localdir is
734 dropped in favor of the safer --include/--prepend-include scheme.
739 AC_COMPILER_IFELSE, AC_FUNC_MBRTOWC, AC_HEADER_STDBOOL,
740 AC_LANG_CONFTEST, AC_LANG_SOURCE, AC_LANG_PROGRAM, AC_LANG_CALL,
741 AC_LANG_FUNC_TRY_LINK, AC_MSG_FAILURE, AC_PREPROC_IFELSE.
744 Obsoleted macros are kept for Autoconf backward compatibility, but
745 should be avoided in configure.ac. Running autoupdate is advised.
748 - AC_DEFINE/AC_DEFINE_UNQUOTED
750 We have to stop using the old compatibility scheme --that tried to
751 avoid useless backslashes-- because Libtool 1.4.3 contains a
753 AC_DEFINE([error_t], [int],
754 [Define to a type to use for \`error_t' if it is not
755 otherwise available.])
757 We have to quote the single quotes and backslashes with \. The old
758 compatibility scheme saw that ` was backslashed, and therefore did
759 not quote the single quote... Failure. Hence, Autoconf 2.54 is not
760 compatible with Libtool. Autoconf 2.55 is, but in some cases might
761 produce more \ than wanted.
763 Please, note that in the future the same problem will happen with
764 AC_MSG_*: use `autoreconf -f -Wall'.
768 - Portability of the Autoconf package to Solaris.
770 - Spurious warnings caused by config.status.
771 This bug is benign, but painful: on some systems (typically
772 FreeBSD), warnings such as:
774 config.status: creating Makefile
775 mv: Makefile: set owner/group (was: 1357/0): Operation not permitted
777 could be issued. This is fixed.
780 Simultaneous executions of config.status are possible again.
782 - Precious variables accumulation
784 config.status could stack several copies of the precious variables
788 ** Plans for later versions
792 The compatibility hooks with the old scheme will be completely
793 removed. Please, advice/use `--build', `--host', and `--target'
796 - AC_CHECK_HEADER, AC_CHECK_HEADERS
798 The tests will be stricter, please make sure your invocations are
803 Shell functions will gradually be introduced, probably starting with
804 Autotest. If you know machines which are in use that you suspect
805 *not* to support shell functions, please run the test suite of
806 Autoconf 2.55 on it, and report the results to
807 bug-autoconf@gnu.org.
811 Special characters in AC_MSG_* need not be quoted. Currently,
812 Autoconf has heuristics to decide when a string is escaped, or has
813 to be escaped. This scheme is fragile, and will be removed; the
814 only risk is uglified messages. Please, run `autoreconf -f -Wall'
815 to find occurrences that will be affected.
817 * Major changes in Autoconf 2.54
819 Released 2002-09-13 by Akim Demaille.
823 - autoreconf no longer changes the version of the gettext/po/intl
824 support files. It now adds the files the correspond to the
825 AM_GNU_GETTEXT_VERSION declared in configure.ac.
827 Warning: It now relies on the 'autopoint' program, which is part
828 of GNU gettext 0.11.4 and newer.
830 Please note that you need to have a GNU gettext version that
831 corresponds at least to the AM_GNU_GETTEXT_VERSION declared
832 in configure.ac. You can upgrade to newer GNU gettext versions,
833 though, without needing to change configure.ac.
835 - The -I DIR or --include=DIR option now appends DIR to the include path
836 instead of prepending; this is for consistency with other GNU tools.
837 The new -B DIR or --prepend-include=DIR option has the old behavior.
842 Now handles all the gory details about LIBOBJS and LTLIBOBJS.
843 Please, remove lines such as
845 # This is necessary so that .o files in LIBOBJS are also
846 # built via the ANSI2KNR-filtering rules.
847 LIBOBJS=`echo $LIBOBJS|sed 's/\.o /\$U.o /g;s/\.o$/\$U.o/'`
849 and read the `AC_LIBOBJ vs LIBOBJS' section. Do not define U in
850 your Makefiles either.
852 - AC_CONFIG_LINKS now makes copies if it can't make links.
854 - AC_FUNC_FNMATCH now tests only for POSIX compatibility, reverting to
855 Autoconf 2.13 behavior. The new macro AC_FUNC_FNMATCH_GNU also
856 tests for GNU extensions to fnmatch, and replaces fnmatch if needed.
858 - AC_FUNC_SETVBUF_REVERSED no longer fails when cross-compiling.
860 - AC_PROG_CC_STDC is integrated into AC_PROG_CC.
862 - AC_PROG_F77 default search no longer includes cf77 and cfg77.
866 AC_C_BACKSLASH_A, AC_CONFIG_LIBOBJ_DIR, AC_GNU_SOURCE,
867 AC_PROG_EGREP, AC_PROG_FGREP, AC_REPLACE_FNMATCH,
868 AC_FUNC_FNMATCH_GNU, AC_FUNC_REALLOC, AC_TYPE_MBSTATE_T.
871 looks for getloadavg.c in the CONFIG_LIBOBJ_DIR.
874 Now defines HAVE_MALLOC to 0 if `malloc' does not work, and asks
875 for an AC_LIBOBJ replacement.
879 - Spurious complaints from `m4_bmatch' about invalid regular
880 expressions are suppressed.
882 - Empty top_builddirs are properly handled.
884 - AC_CHECK_MEMBER works correctly when the member is an aggregate.
887 Now colon in the optional path arguments are properly handled.
889 ** Improved portability
891 - Both Autoconf the package, and the scripts it produces, should run
892 more reliably with Zsh. Bear in mind it is the default Bourne shell
895 - Autoconf and the scripts it produces no longer assume the existence of
896 the obsolescent commands egrep and fgrep.
900 - Limitations of Make
904 The GNATS base moved to
905 http://bugs.gnu.org/cgi-bin/gnatsweb.pl?database=autoconf
906 (It is no longer available, though.)
911 Now contains the list of ouput variables and files (AC_SUBST,
914 * Major changes in Autoconf 2.53
916 Released 2002-03-08 by Akim Demaille.
920 Perl 5.005_03 or later is required: autom4te is written in Perl and is
921 needed by autoconf. autoheader, autoreconf, ifnames, and autoscan are
927 Argument requirements, output variables, defined macros.
928 - M4sugar, M4sh, Autotest
930 - Double quoting macros
931 AC_TRY_CPP, AC_TRY_COMPILE, AC_TRY_LINK and AC_TRY_RUN.
933 The Autoconf manual is now distributed under the terms of the GNU FDL.
934 - Section `Hosts and Cross-Compilation'
935 Explains the rationale for the 2.5x changes in the cross-compilation
936 chain, and in the relationships between build, host, and target
938 Emphasizes that `cross-compilation' == `--host is given'.
939 If you are working on compilers etc., be sure to read this section.
940 - Section `AC_LIBOBJ vs. LIBOBJS'
941 Explains why assigning LIBOBJS directly is now an error.
942 Details how to update the code.
947 Now used instead of hard coded line numbers.
948 This eases the comparison of `configure's, and diminishes the
949 pressure over control version archives.
950 Automatic replacement for shells that don't support this feature.
951 - New output variables
952 @builddir@, @top_builddir@, @abs_srcdir@, @abs_top_srcdir@, @abs_builddir@,
957 Autoconf and Autotest modes are provided.
962 New, used by the Autoconf suite to cache and speed up most processing.
964 Supported by autom4te, autoconf and autoheader.
966 Replaces --autoconf-dir and --localdir in autoconf, autoheader,
967 autoupdate, and autoreconf.
969 No longer passes --cygnus, --foreign, --gnits, --gnu, --include-deps:
970 automake options are to be given via AUTOMAKE_OPTIONS.
972 Runs gettextize and libtoolize when appropriate.
974 --m4dir is no longer supported.
976 Now runs only in the specified directories, defaulting to `.',
977 but understands AC_CONFIG_SUBDIRS for dependent directories.
978 Before, it used to run on all the `configure.ac' found in the
980 Independent packages are properly updated.
984 - The top level $prefix is propagated to the AC_CONFIG_SUBDIRS configures.
986 Under the user pressure, $? is finally available. Probably a mistake.
987 - AC_F77_LIBRARY_LDFLAGS now supports the HP/UX f90 compiler.
988 - Precious variables accumulation
989 config.status could stack several copies of the precious variables
991 - AC_PATH_PROG and family.
992 Works properly when given a literal path.
994 Somewhere since 2.13, the result had been reversed.
998 - AC_C_BIGENDIAN supports the cross-compiling case.
999 - AC_C_BIGENDIAN accepts ACTION-IF-TRUE, ACTION-IF-FALSE, and
1000 ACTION-IF-UNKNOWN arguments. All are facultative, and the default
1001 for ACTION-IF-TRUE is to define WORDS_BIGENDIAN like AC_C_BIGENDIAN
1003 - AC_C_LONG_DOUBLE now succeeds only if `long double' has more range or
1004 precision than `double'.
1009 It now defines the preprocessor symbols PACKAGE_NAME,
1010 PACKAGE_TARNAME, PACKAGE_VERSION, PACKAGE_STRING, and
1014 Admits a fourth optional parameter: the tar name.
1016 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS.
1017 Provide the user with srcdir, ac_srcdir, ac_top_srcdir, ac_builddir,
1018 ac_top_builddir, ac_abs_srcdir, ac_abs_top_srcdir, ac_abs_builddir,
1019 ac_abs_top_builddir.
1021 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS and AC_OUTPUT.
1022 Are much less expensive when using long lists of files.
1025 Works with shell variables, and non alphanumeric names.
1029 - AC_FUNC_STRERROR_R now sets STRERROR_R_CHAR_P, not HAVE_WORKING_STRERROR_R,
1030 because POSIX 1003.1-200x draft 7 says strerror_r returns int, not char *.
1032 - AC_FUNC_STRTOD substitutes POW_LIB.
1037 * Major changes in Autoconf 2.52
1039 Released 2001-07-18 by Akim Demaille.
1044 This feature was present in autoconf 2.50 but was not documented.
1045 For example, `@<:@' is translated to `[' just before output. This
1046 is useful when writing strings that contain unbalanced quotes, or
1047 other hard-to-quote constructs.
1048 - m4_pattern_forbid, m4_pattern_allow
1049 - Tips for upgrading from 2.13.
1050 - Using autoscan to maintain a configure.ac.
1053 - Now include stdint.h.
1054 - sys/types.h and sys/stat.h are guarded.
1055 - strings.h is included if available, and not conflicting with string.h.
1058 - The test suite is more robust and presents less false failures.
1059 - Invocation of GNU M4 now robust to POSIXLY_CORRECT.
1060 - configure accepts --prefix='' again.
1061 - AC_CHECK_LIB works properly when its first argument is not a
1063 - HAVE_INTTYPES_H is defined only if not conflicting with sys/types.h.
1064 - build_, host_, and target_alias are AC_SUBST as in 2.13.
1065 - AC_ARG_VAR properly propagates precious variables inherited from the
1066 environment to ./config.status.
1067 - Using --program-suffix/--program-prefix is portable.
1068 - Failures to detect the default compiler's output extension are less
1070 - `config.status foo' works properly when `foo' depends on variables
1071 set in an AC_CONFIG_THING INIT-CMD.
1072 - autoheader is more robust to broken input.
1073 - Fixed Fortran name-mangling and link tests on a number of systems,
1074 e.g. NetBSD; see AC_F77_DUMMY_MAIN, below.
1077 - AC_CHECK_HEADER and AC_CHECK_HEADERS support a fourth argument to
1078 specify pre-includes. In this case, the headers are compiled with
1079 cc, not merely preprocessed by cpp. Therefore it is the _usability_
1080 of a header which is checked for, not just its availability.
1081 - AC_ARG_VAR refuses to run configure when precious variables have
1083 - Versions of compilers are dumped in the logs.
1084 - AC_CHECK_TYPE recognizes use of `foo_t' as a replacement type.
1087 - AC_PATH_XTRA only adds -ldnet to $LIBS if it's needed to link.
1088 - AC_FUNC_WAIT3 and AC_SYS_RESTARTABLE_SYSCALLS are obsoleted.
1089 - AM_FUNC_ERROR_AT_LINE, AM_FUNC_FNMATCH, AM_FUNC_MKTIME,
1090 AM_FUNC_OBSTACK, and AM_FUNC_STRTOD are now activated.
1091 Be sure to read `Upgrading from Version 2.13' to understand why
1092 running `autoupdate' is needed.
1093 - AC_F77_DUMMY_MAIN, AC_F77_MAIN: new macros to detect whether
1094 a main-like routine is required/possible when linking C/C++ with
1095 Fortran. Users of e.g. AC_F77_WRAPPERS should be aware of these.
1096 - AC_FUNC_GETPGRG behaves better when cross-compiling.
1098 * Major changes in Autoconf 2.51
1099 There was no release of Autoconf 2.51 since some packagers had used
1100 this version number without permission to ship intermediary versions
1101 of 2.50. The version was skipped to avoid confusion.
1103 * Major changes in Autoconf 2.50
1105 Released 2001-05-21 by Akim Demaille.
1107 ** Lots of bug fixes
1108 There have been far too many to enumerate them here. Check out
1109 ChangeLog if you really want to know more.
1111 ** Improved documentation
1112 In particular, portability issues are better covered.
1115 All the standard GNU Makefile targets are supported. The layout has
1116 changed: m4/ holds the M4 extensions Autoconf needs for its
1117 configuration, doc/ contains the documentation, and tests/ contains
1120 ** Man pages are provided
1121 For autoconf, autoreconf, autoupdate, autoheader, autoscan, ifnames,
1122 config.guess, config.sub.
1126 Provides a safe and powerful means to trace the macro uses. This
1127 provide the parsing layer for tools which need to `study'
1131 Specify what category of warnings should be enabled.
1133 - When recursing into subdirectories, try for configure.gnu before
1134 configure to adapt for packages not using autoconf on case-insensitive
1138 More errors are now caught (circular AC_REQUIRE dependencies,
1139 AC_DEFINE in the action part of an AC_CACHE_CHECK, too many pops
1140 etc.). In addition, their location and call stack are given.
1143 autoupdate is much more powerful, and is able to provide the glue code
1144 which might be needed to move from an old macro to its newer
1147 You are strongly encouraged to use it to modernize both your
1148 `configure.in' and your .m4 extension files.
1151 The internal machinery of autoheader has completely changed. As a
1152 result, using `acconfig.h' should be considered to be obsoleted, and
1153 you are encouraged to get rid of it using the AH macros.
1158 ** Fortran 77 compilers
1159 Globally, the support for Fortran 77 is considerably improved.
1161 Support for automatically determining a Fortran 77 compiler's
1162 name-mangling scheme. New CPP macros F77_FUNC and F77_FUNC_ are
1163 provided to wrap C/C++ identifiers, thus making it easier and more
1164 transparent for C/C++ to call Fortran 77 routines, and Fortran 77 to
1165 call C/C++ routines. See the Texinfo documentation for details.
1168 The test suite no longer uses DejaGNU. It should be easy to submit
1169 test cases in this new framework.
1172 - --help, --help=long, -hl
1173 no longer dumps useless items.
1175 lists only specific options.
1176 - --help=recursive, -hr
1177 displays the help of all the embedded packages.
1178 - Remembers environment variables when reconfiguring.
1179 The previous scheme to set envvar before running configure was
1181 what prevented configure from remembering the environment in which
1182 it was run, therefore --recheck was run in an inconsistent
1183 environment. Now, one should run
1185 and then --recheck will work properly. Variables declared with
1186 AC_ARG_VAR are also preserved.
1188 $build defaults to `config.guess`, $host to $build, and then $target
1190 Cross-compilation is a global status of the package, it no longer
1191 depends upon the current language.
1192 Cross compilation is enabled iff the user specified `--host'.
1193 `configure' now fails if it can't run the executables it compiles,
1194 unless cross-compilation is enabled.
1196 The cache file is disabled by default. The new options
1197 `--config-cache', `-C' set the cache to `config.cache'.
1201 Much faster on most architectures.
1202 - concurrent executions
1203 It is safe to use `make -j' with config.status.
1204 - human interface improved
1205 It is possible to invoke
1206 ./config.status foobar
1207 instead of the former form (still valid)
1208 CONFIG_COMMANDS= CONFIG_HEADERS= CONFIG_LINKS= \
1209 CONFIG_FILES=foobar:foo.in:bar.in \
1211 The same holds for configuration headers and links.
1212 You can instantiate unknown files and headers:
1213 ./config.status --header foo.h:foo.h.in --file bar:baz
1214 - has a useful --help
1215 - accepts special file name "-" for stdin/stdout
1220 Specify additional copyright information.
1223 Now expects the identity of the package as argument.
1227 Most macros, if not all, now strictly follow the `one quotation
1228 level' rule. This results in a more predictable expansion.
1231 A sly bug in the AC_REQUIRE machinery, which could produce incorrect
1232 configure scripts, was fixed by Axel Thimm.
1236 Document and ask for the registration of an envvar.
1239 Specifies the file which `configure' should look for when trying to
1240 find the source tree (used to be handled by AC_INIT).
1242 - AC_CONFIG_COMMANDS
1243 To add new actions to config.status. Should be used instead of
1247 Replaces AC_LINK_FILES.
1249 - AC_CONFIG_HEADERS, AC_CONFIG_COMMANDS, AC_CONFIG_SUBDIRS,
1250 AC_CONFIG_LINKS, and AC_CONFIG_FILES
1251 They now obey sh: you should no longer use shell variables as
1252 argument. Instead of
1254 test "$package_foo_enabled" = yes && $my_subdirs="$my_subdirs foo"
1255 AC_CONFIG_SUBDIRS($my_subdirs)
1259 if test "$package_foo_enabled" = yes; then
1260 AC_CONFIG_SUBDIRS(foo)
1264 To format an Autoconf macro's help string so that it looks pretty
1265 when the user executes `configure --help'.
1268 ** Generic Test Macros
1270 The interface of the AC_CHECK families of macros (decl, header,
1271 type, member, func) is now uniform. They support the same set of
1274 - AC_CHECK_DECL, AC_CHECK_DECLS
1275 To check whether a symbol is declared.
1277 - AC_CHECK_SIZEOF, AC_C_CHAR_UNSIGNED.
1278 No longer need a cross-compilation default.
1281 The test it performs is much more robust than previously, and makes
1282 it possible to test builtin types in addition to typedefs.
1283 It is now schizophrenic:
1284 - AC_CHECK_TYPE(TYPE, REPLACEMENT)
1285 remains for backward compatibility, but its use is discouraged.
1286 - AC_CHECK_TYPE(TYPE, IF-FOUND, IF-NOT-FOUND, INCLUDES)
1287 behaves exactly like the other AC_CHECK macros.
1290 Checks whether given types are supported by the system.
1292 - AC_CHECK_MEMBER, AC_CHECK_MEMBERS
1293 Check for given members in aggregates (e.g., pw_gecos in struct
1297 Checks if the compiler supports ISO C, included when needs special
1301 Checking whether the preprocessor indicates missing includes by the
1302 error code. stderr is checked by AC_TRY_CPP only as a fallback.
1305 Takes a language as argument and replaces AC_LANG_C,
1306 AC_LANG_CPLUSPLUS and AC_LANG_FORTRAN77.
1308 - AC_LANG_PUSH, AC_LANG_POP
1309 Are preferred to AC_LANG_SAVE, AC_LANG_RESTORE.
1312 - AC_FUNC_CHOWN, AC_FUNC_MALLOC, AC_FUNC_STRERROR_R,
1313 AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK, AC_FUNC_STAT, AC_FUNC_LSTAT,
1314 AC_FUNC_ERROR_AT_LINE, AC_FUNC_OBSTACK, AC_FUNC_STRTOD, AC_FUNC_FSEEKO.
1318 Sets GETGROUPS_LIBS.
1320 - AC_FUNC_GETLOADAVG
1321 Defines `HAVE_STRUCT_NLIST_N_UN_N_NAME' instead of `NLIST_NAME_UNION'.
1324 Now integrates `AC_DECL_YYTEXT' which is obsoleted.
1327 Arrange for large-file support.
1329 - AC_EXEEXT, AC_OBJEXT
1330 You are no longer expected to use them: their computation is
1331 performed by default.
1333 ** C++ compatibility
1334 Every macro has been revisited in order to support at best CC=c++.
1336 Major changes in Autoconf 2.14:
1337 There was no release of GNU Autoconf 2.14.
1339 Major changes in Autoconf 2.13:
1341 Released 1999-05-01 by Ben Elliston.
1343 * Support for building on Win32 systems where the only available C or
1344 C++ compiler is the Microsoft Visual C++ command line compiler
1345 (`cl'). Additional support for building on Win32 systems which are
1346 using the Cygwin or Mingw32 environments.
1347 * Support for alternative object file and executable file extensions.
1348 On Win32, for example, these are .obj and .exe. These are discovered
1349 using AC_OBJEXT and AC_EXEEXT, which substitute @OBJEXT@ and
1350 @EXEEXT@ in the output, respectively.
1351 * New macros: AC_CACHE_LOAD, AC_CACHE_SAVE, AC_FUNC_SELECT_ARGTYPES,
1352 AC_VALIDATE_CACHED_SYSTEM_TUPLE, AC_SEARCH_LIBS, AC_TRY_LINK_FUNC,
1353 AC_C_STRINGIZE, AC_CHECK_FILE(S), AC_PROG_F77 (and friends).
1354 * AC_DEFINE now has an optional third argument for a description to be
1355 placed in the config header input file (e.g. config.h.in).
1356 * The C++ code fragment compiled for the C++ compiler test had to be
1357 improved to include an explicit return type for main(). This was
1358 causing failures on systems using recent versions of the EGCS C++
1360 * Fixed an important bug in AC_CHECK_TYPE that would cause a configure
1361 script to report that `sometype_t' was present when only `type_t'
1363 * Merge of the FSF version of config.guess and config.sub to modernize
1364 these scripts. Add support for a few new hosts in config.guess.
1365 Incorporate latest versions of install-sh, mkinstalldirs and
1366 texinfo.tex from the FSF.
1367 * autoreconf is capable of running automake if necessary (and
1369 * Support for Fortran 77. See the Texinfo documentation for details.
1370 * Bug fixes and workarounds for quirky bugs in vendor utilities.
1372 Major changes in Autoconf 2.12:
1374 Released 1996-11-26 by David J. MacKenzie
1376 * AC_OUTPUT and AC_CONFIG_HEADER can create output files by
1377 concatenating multiple input files separated by colons, like so:
1378 AC_CONFIG_HEADER(config.h:conf.pre:config.h.in:conf.post)
1379 AC_OUTPUT(Makefile:Makefile.in:Makefile.rules)
1380 The arguments may be shell variables, to compute the lists on the fly.
1381 * AC_LINK_FILES and AC_CONFIG_SUBDIRS may be called multiple times.
1382 * New macro AC_OUTPUT_COMMANDS adds more commands to run in config.status.
1385 Major changes in Autoconf 2.11:
1387 Released November 18th, 1996, by David J. MacKenzie
1389 * AC_PROG_CC and AC_PROG_CXX check whether the compiler works.
1390 They also default CFLAGS/CXXFLAGS to "-g -O2" for gcc, instead of "-g -O".
1391 * AC_REPLACE_FUNCS defines HAVE_foo if the system has the function `foo'.
1392 * AC_CONFIG_HEADER expands shell variables in its argument.
1393 * New macros: AC_FUNC_FNMATCH, AC_FUNC_SETPGRP.
1394 * The "checking..." messages and the source code for test programs that
1395 fail are saved in config.log.
1396 * Another workaround has been added for seds with small command length limits.
1397 * config.sub and config.guess recognize more system types.
1400 Major changes in Autoconf 2.10:
1402 Released May 7th, 1996, by Roland McGrath
1405 * The cache variable names used by `AC_CHECK_LIB(LIB, FUNC, ...)' has
1406 changed: now $ac_cv_lib_LIB_FUNC, previously $ac_cv_lib_LIB.
1408 Major changes in Autoconf 2.9:
1410 Released March 16th, 1996, by Roland McGrath
1414 Major changes in Autoconf 2.8:
1416 Released March 8th, 1996, by Roland McGrath
1420 Major changes in Autoconf 2.7:
1422 Released November 22nd, 1995, by David J. MacKenzie
1426 Major changes in Autoconf 2.6:
1428 Released November 20th, 1995, by David J. MacKenzie
1432 Major changes in Autoconf 2.5:
1434 Released November 17th, 1995, by Roland McGrath
1436 * New configure options --bindir, --libdir, --datadir, etc., with
1437 corresponding output variables.
1438 * New macro: AC_CACHE_CHECK, to make using the cache easier.
1439 * config.log contains the command being run as well as any output from it.
1440 * AC_CHECK_LIB can check for libraries with "." or "/" or "+" in their name.
1441 * AC_PROG_INSTALL doesn't cache a name for install-sh, for sharing caches.
1442 * AC_CHECK_PROG, AC_PATH_PROG, AC_CHECK_PROGS, AC_PATH_PROGS, and
1443 AC_CHECK_TOOL can search a path other than $PATH.
1444 * AC_CHECK_SIZEOF takes an optional size to use when cross-compiling.
1446 Major changes in Autoconf 2.4:
1448 Released June 14th, 1995, by David J. MacKenzie
1450 * Fix a few bugs found by Emacs testers.
1452 Major changes in Autoconf 2.3:
1454 Released March 27th, 1995, by David J. MacKenzie
1456 * Fix the cleanup trap in several ways.
1457 * Handle C compilers that are picky about option placement.
1458 * ifnames gets the version number from the right directory.
1460 Major changes in Autoconf 2.2:
1462 Released March 8th, 1995, by David J. MacKenzie
1464 * The ifnames utility is much faster but requires a "new awk" interpreter.
1465 * AC_CHECK_LIB and AC_HAVE_LIBRARY check and add the new
1466 library before existing libs, not after, in case it uses them.
1467 * New macros: AC_FUNC_GETPGRP, AC_CHECK_TOOL.
1468 * Lots of bug fixes.
1469 * Many additions to the TODO file :-)
1471 Major changes in Autoconf 2.1:
1473 Released November 4th, 1994, by David J. MacKenzie
1476 * More explanations in the manual.
1477 * Fix a spurious failure in the testsuite.
1478 * Clarify some warning messages.
1479 * autoreconf by default only rebuilds configure and config.h.in files
1480 that are older than any of their particular input files; there is a
1481 --force option to use after installing a new version of Autoconf.
1483 Thanks to everybody who's submitted changes and additions to Autoconf!
1484 I've incorporated many of them, and am still considering others for
1485 future releases -- but I didn't want to postpone this release indefinitely.
1487 Caution: don't indiscriminately rebuild configure scripts with
1488 Autoconf version 2. Some configure.in files need minor adjustments to
1489 work with it; the documentation has a chapter on upgrading. A few
1490 configure.in files, including those for GNU Emacs and the GNU C
1491 Library, need major changes because they relied on undocumented
1492 internals of version 1. Future releases of those packages will have
1493 updated configure.in files.
1495 It's best to use GNU M4 1.3 (or later) with Autoconf version 2.
1496 Autoconf now makes heavy use of M4 diversions, which were implemented
1497 inefficiently in GNU M4 releases before 1.3.
1499 Major changes in Autoconf 2.0:
1501 Released October 26th, 1994, by David J. MacKenzie
1503 ** New copyright terms:
1504 * There are no restrictions on distribution or use of configure scripts.
1507 * Autoconf manual is reorganized to make information easier to find
1508 and has several new indexes.
1509 * INSTALL is reorganized and clearer and is now made from Texinfo source.
1512 * autoscan to generate a preliminary configure.in for a package by
1513 scanning its source code for commonly used nonportable functions,
1514 programs, and header files.
1515 * ifnames to list the symbols used in #if and #ifdef directives in a
1517 * autoupdate to update a configure.in to use the version 2 macro names.
1518 * autoreconf to recursively remake configure and configuration header
1519 files in a source tree.
1521 ** Changed utilities:
1522 * autoheader can take pieces of acconfig.h to replace config.h.{top,bot}.
1523 * autoconf and autoheader can look for package-local definition files
1524 in an alternate directory.
1527 * AC_CACHE_VAL to share results of tests between configure runs.
1528 * AC_DEFUN to define macros, automatically AC_PROVIDE them, and ensure
1529 that macros invoked with AC_REQUIRE don't interrupt other macros.
1530 * AC_CONFIG_AUX_DIR, AC_CANONICAL_SYSTEM, AC_CANONICAL_HOST, AC_LINK_FILES to
1531 support deciding unguessable features based on the host and target types.
1532 * AC_CONFIG_SUBDIRS to recursively configure a source tree.
1533 * AC_ARG_PROGRAM to use the options --program-prefix,
1534 --program-suffix, and --program-transform-name to change the names
1535 of programs being installed.
1536 * AC_PREFIX_DEFAULT to change the default installation prefix.
1537 * AC_TRY_COMPILE to compile a test program without linking it.
1538 * AC_CHECK_TYPE to check whether sys/types.h or stdlib.h defines a given type.
1539 * AC_CHECK_LIB to check for a particular function and library.
1540 * AC_MSG_CHECKING and AC_MSG_RESULT to print test results, on a single line,
1541 whether or not the test succeeds. They obsolete AC_CHECKING and AC_VERBOSE.
1542 * AC_SUBST_FILE to insert one file into another.
1543 * AC_FUNC_MEMCMP to check whether memcmp is 8-bit clean.
1544 * AC_FUNC_STRFTIME to find strftime even if it's in -lintl.
1545 * AC_FUNC_GETMNTENT to find getmntent even if it's in -lsun or -lseq.
1546 * AC_HEADER_SYS_WAIT to check whether sys/wait.h is POSIX.1 compatible.
1549 * Many macros renamed systematically, but old names are accepted for
1550 backward compatibility.
1551 * AC_OUTPUT adds the "automatically generated" comment to
1552 non-Makefiles where it finds @configure_input@ in an input file, to
1553 support files with various comment syntaxes.
1554 * AC_OUTPUT does not replace "prefix" and "exec_prefix" in generated
1555 files when they are not enclosed in @ signs.
1556 * AC_OUTPUT allows the optional environment variable CONFIG_STATUS to
1557 override the file name "config.status".
1558 * AC_OUTPUT takes an optional argument for passing variables from
1559 configure to config.status.
1560 * AC_OUTPUT and AC_CONFIG_HEADER allow you to override the input-file names.
1561 * AC_OUTPUT automatically substitutes the values of CFLAGS, CXXFLAGS,
1562 CPPFLAGS, and LDFLAGS from the environment.
1563 * AC_PROG_CC and AC_PROG_CXX now set CFLAGS and CXXFLAGS, respectively.
1564 * AC_PROG_INSTALL looks for install-sh or install.sh in the directory
1565 specified by AC_CONFIG_AUXDIR, or srcdir or srcdir/.. or
1566 srcdir/../.. by default.
1567 * AC_DEFINE, AC_DEFINE_UNQUOTED, and AC_SUBST are more robust and smaller.
1568 * AC_DEFINE no longer prints anything, because of the new result reporting
1569 mechanism (AC_MSG_CHECKING and AC_MSG_RESULT).
1570 * AC_VERBOSE pays attention to --quiet/--silent, not --verbose.
1571 * AC_ARG_ENABLE and AC_ARG_WITH support whitespace in the arguments to
1572 --enable- and --with- options.
1573 * AC_CHECK_FUNCS and AC_CHECK_HEADERS take optional shell commands to
1574 execute on success or failure.
1575 * Checking for C functions in C++ works.
1578 * AC_REMOTE_TAPE and AC_RSH removed; too specific to tar and cpio, and
1579 better maintained with them.
1580 * AC_ARG_ARRAY removed because no one was likely using it.
1581 * AC_HAVE_POUNDBANG replaced with AC_SYS_INTERPRETER, which doesn't
1582 take arguments, for consistency with all of the other specific checks.
1585 * Comes with config.sub and config.guess, and uses them optionally.
1586 * Uses config.cache to cache test results. An alternate cache file
1587 can be selected with the --cache-file=FILE option.
1588 * Uses optional shell scripts $prefix/share/config.site and
1589 $prefix/etc/config.site to perform site or system specific initializations.
1590 * configure saves compiler output to ./config.log for debugging.
1591 * New files autoconf.m4 and autoheader.m4 load the other Autoconf macros.
1592 * acsite.m4 is the new name for the system-wide aclocal.m4.
1593 * Has a DejaGnu test suite.
1595 Major changes in Autoconf 1.11:
1597 * AC_PROG_INSTALL calls install.sh with the -c option.
1598 * AC_SET_MAKE cleans up after itself.
1599 * AC_OUTPUT sets prefix and exec_prefix if they weren't set already.
1600 * AC_OUTPUT prevents shells from looking in PATH for config.status.
1602 Plus a few other bug fixes.
1604 Major changes in Autoconf 1.10:
1606 * autoheader uses config.h.bot if present, analogous to config.h.top.
1607 * AC_PROG_INSTALL looks for install.sh in srcdir or srcdir/.. and
1609 * AC_PROG_CXX looks for cxx as a C++ compiler.
1611 Plus several bugs fixed.
1613 Major changes in Autoconf 1.9:
1615 * AC_YYTEXT_POINTER replaces AC_DECLARE_YYTEXT.
1616 * AC_SIZEOF_TYPE generates the cpp symbol name automatically,
1617 and autoheader generates entries for those names automatically.
1618 * AC_FIND_X gets the result from xmkmf correctly.
1619 * AC_FIND_X assumes no X if --without-x was given.
1620 * AC_FIND_XTRA adds libraries to the variable X_EXTRA_LIBS.
1621 * AC_PROG_INSTALL finds OSF/1 installbsd.
1623 Major changes in Autoconf 1.8:
1626 * New macros AC_LANG_C, AC_LANG_CPLUSPLUS, AC_LANG_SAVE, AC_LANG_RESTORE,
1627 AC_PROG_CXX, AC_PROG_CXXCPP, AC_REQUIRE_CPP
1628 for checking both C++ and C features in one configure script.
1629 * New macros AC_CHECKING, AC_VERBOSE, AC_WARN, AC_ERROR for printing messages.
1630 * New macros AC_FIND_XTRA, AC_MMAP, AC_SIZEOF_TYPE, AC_PREREQ,
1631 AC_SET_MAKE, AC_ENABLE.
1634 * AC_FIND_X looks for X in more places.
1635 * AC_PROG_INSTALL defaults to install.sh instead of cp, if it's in srcdir.
1636 install.sh is distributed with Autoconf.
1637 * AC_DECLARE_YYTEXT has been removed because it can't work, pending
1638 a rewrite of quoting in AC_DEFINE.
1639 * AC_OUTPUT adds its comments in C format when substituting in C files.
1640 * AC_COMPILE_CHECK protects its ECHO-TEXT argument with double quotes.
1642 ** New or changed command line options:
1643 * configure accepts --enable-FEATURE[=ARG] and --disable-FEATURE options.
1644 * configure accepts --without-PACKAGE, which sets withval=no.
1645 * configure accepts --x-includes=DIR and --x-libraries=DIR.
1646 * Giving --with-PACKAGE no argument sets withval=yes instead of withval=1.
1647 * configure accepts --help, --version, --silent/--quiet, --no-create options.
1648 * configure accepts and ignores most other Cygnus configure options, and
1649 warns about unknown options.
1650 * config.status accepts --help, --version options.
1652 ** File names and other changes:
1653 * Relative srcdir values are not made absolute.
1654 * The values of @prefix@ and @exec_prefix@ and @top_srcdir@ get substituted.
1655 * Autoconf library files are installed in ${datadir}/autoconf, not ${datadir}.
1656 * autoheader optionally copies config.h.top to the beginning of config.h.in.
1657 * The example Makefile dependencies for configure et al. work better.
1658 * Namespace cleanup: all shell variables used internally by Autoconf
1659 have names beginning with `ac_'.
1661 More big improvements are in process for future releases, but have not
1662 yet been (variously) finished, integrated, tested, or documented enough
1665 Major changes in Autoconf 1.7:
1667 * New macro AC_OBSOLETE.
1668 * Bugs in Makefile.in fixed.
1669 * AC_LONG_FILE_NAMES improved.
1671 Major changes in Autoconf 1.6:
1673 * New macro AC_LONG_64_BITS.
1674 * Multiple .h files can be created.
1675 * AC_FIND_X looks for X files directly if it doesn't find xmkmf.
1676 * AC_ALLOCA defines C_ALLOCA if using alloca.c.
1677 * --with-NAME can take a value, e.g., --with-targets=sun4,hp300bsd.
1678 * Unused --no-create option to configure removed.
1679 * autoheader doesn't change the timestamp of its output file if
1680 the file didn't change.
1681 * All macros that look for libraries now use AC_HAVE_LIBRARY.
1682 * config.status checks three optional environment variables to
1683 modify its behavior.
1684 * The usual bug fixes.
1686 Major changes in Autoconf 1.5:
1688 * New macros AC_FIND_X, AC_OFF_T, AC_STAT_MACROS_BROKEN, AC_REVISION.
1689 * autoconf and autoheader scripts have GNU standards conforming
1690 --version and --help options (they print their message and exit).
1693 Major changes in Autoconf 1.4:
1695 * New macros AC_HAVE_POUNDBANG, AC_TIME_WITH_SYS_TIME, AC_LONG_DOUBLE,
1696 AC_GETGROUPS_T, AC_DEFINE_UNQUOTED.
1697 * autoconf and autoheader use the M4 environment variable to determine the
1698 name of the M4 program to use.
1699 * The --macrodir option to autoconf and autoheader specifies the directory
1700 in which acspecific.m4, acgeneral.m4, etc. reside if not the default.
1701 * autoconf and autoheader can take `-' as their file names, which means to
1702 read stdin as input.
1703 * Resulting configure scripts can take a --verbose option which causes them
1704 to print the results of their tests.
1705 * AC_DEFINE quotes its second argument in such a way that spaces, magic
1706 shell characters, etc. will be preserved during various stages of
1707 expansion done by the shell. If you don't want this, use
1708 AC_DEFINE_UNQUOTED instead.
1709 * Much textual processing done with external calls to tr and sed have been
1710 internalized with builtin M4 `patsubst' and `translit' calls.
1711 * AC_OUTPUT doesn't hardwire the file names it outputs. Instead, you can
1712 set the shell variables `gen_files' and `gen_config' to the list of
1713 file names to output.
1714 * AC_DECLARE_YYTEXT does an AC_SUBST of `LEX_OUTPUT_ROOT', which may be
1715 "lex.yy" or "lexyy", depending on the system.
1716 * AC_PROGRAMS_CHECK takes an optional third arg. If given, it is used as
1718 * If AC_ALLOCA chooses alloca.c, it also defines STACK_DIRECTION.
1719 * AC_CONST works much more reliably on more systems.
1722 Major changes in Autoconf 1.3:
1724 configure no longer requires awk for packages that use a config.h.
1725 Support handling --with-PACKAGE options.
1726 New `autoheader' script to create `config.h.in' from `configure.in'.
1727 Ignore troublesome -lucb and -lPW when searching for alloca.
1728 Rename --exec_prefix to --exec-prefix for GNU standards conformance.
1729 Improve detection of STDC library.
1730 Add AC_HAVE_LIBRARY to check for non-default libraries.
1731 Function checking should work with future GNU libc releases.
1733 Major changes in Autoconf 1.2:
1735 The --srcdir option is now usually unnecessary.
1736 Add a file containing sample comments describing CPP macros.
1737 A comment in config.status tells which host it was configured on.
1738 Substituted variable values can now contain commas.
1739 Fix bugs in various feature checks.
1741 Major changes in Autoconf 1.1:
1743 Added AC_STRCOLL macro.
1744 Made AC_GETLOADAVG check for more things.
1745 AC_OUTPUT argument is now optional.
1750 Copyright (C) 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002,
1751 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
1753 This program is free software: you can redistribute it and/or modify
1754 it under the terms of the GNU General Public License as published by
1755 the Free Software Foundation, either version 3 of the License, or
1756 (at your option) any later version.
1758 This program is distributed in the hope that it will be useful,
1759 but WITHOUT ANY WARRANTY; without even the implied warranty of
1760 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1761 GNU General Public License for more details.
1763 You should have received a copy of the GNU General Public License
1764 along with this program. If not, see <http://www.gnu.org/licenses/>.