1 GNU Autoconf NEWS - User visible changes.
3 * Major changes in Autoconf 2.62a (2008-??-??)
5 ** AC_C_BIGENDIAN does not mistakenly report "universal" for some
6 bigendian hosts, a regression introduced with universal binary
9 ** AC_PATH_X now includes /lib64 and /usr/lib64 in its list of default
12 ** AC_USE_SYSTEM_EXTENSIONS no longer conflicts with an external
13 AC_DEFINE([__EXTENSIONS__]). This fixes a regression introduced in
14 2.62 when using macros such as AC_AIX that were made obsolete in
15 favor of the more portable AC_USE_SYSTEM_EXTENSIONS.
17 ** AC_CHECK_TARGET_TOOLS is usable in the non-cross-compile case.
19 ** Newly obsolete macros
20 The following macro has been marked obsolete, since current porting
21 targets can safely assume C89 semantics that signal handlers return
22 void. We have no current plans to remove the macro.
26 ** The macros m4_map and m4_map_sep now ignore any list elements
27 consisting of just empty quotes, and m4_map_sep now expands its
28 separator. This fixes a regression in 2.62 when these macros were
29 first documented, for the sake of clients expecting the semantics
30 that these macros had prior to that time. The new macros m4_mapall
31 and m4_mapall_sep, along with extra quoting of the separator, can
32 be used to get the semantics that m4_map_sep had in 2.62.
34 ** Clients of m4_expand, such as AS_HELP_STRING and AT_SETUP, can now
35 handle properly quoted but otherwise unbalanced parentheses (for
36 some macros, this fixes a regression in 2.62).
38 ** Two new quadrigraphs have been introduced: @{:@ for (, and @:}@ for ),
39 allowing the output of unbalanced parentheses in more contexts.
41 ** The following m4sugar macros are new:
42 m4_joinall m4_mapall m4_mapall_sep m4_reverse m4_set_add
43 m4_set_add_all m4_set_contains m4_set_contents m4_set_delete
44 m4_set_difference m4_set_dump m4_set_empty m4_set_foreach
45 m4_set_intersection m4_set_list m4_set_listc m4_set_remove
46 m4_set_size m4_set_union
48 ** The following m4sugar macros now accept multiple arguments, as is the
49 case with underlying m4:
50 m4_defn m4_popdef m4_undefine
52 ** The following m4sugar macros now guarantee linear scaling; they
53 previously had linear scaling with m4 1.6 but quadratic scaling
54 when using m4 1.4.x. All macros built on top of these also gain
55 the scaling improvements.
56 m4_bmatch m4_bpatsubsts m4_case m4_cond m4_do m4_dquote_elt
57 m4_foreach m4_join m4_list_cmp m4_map m4_map_sep m4_max
60 ** AT_KEYWORDS once again performs expansion on its argument, such that
61 AT_KEYWORDS([m4_if([$1], [], [default])]) no longer complains about
62 the possibly unexpanded m4_if [regression introduced in 2.62].
64 ** Config header templates `#undef UNDEFINED /* comment */' do not lead to
65 nested comments any more; regression introduced in 2.62.
68 * Major changes in Autoconf 2.62 (2008-04-05) [stable]
69 Released by Eric Blake, based on git versions 2.61a.*.
71 ** Many optimizations have been applied to make overall execution faster.
73 ** Autotest now makes use of shell functions.
75 ** config.status now uses awk instead of sed also for config headers.
77 - As a side effect, AC_DEFINE and AC_DEFINE_UNQUOTED now handle multi-line
78 values, i.e., backslash-newline combinations are handled correctly.
79 Further, for config headers, the total size of values is not limited by
80 the POSIX length limit of text lines any more, only each single line.
82 ** New config variable `top_build_prefix'.
84 ** New Autoconf macros:
85 AC_AUTOCONF_VERSION AC_OPENMP AC_PATH_PROGS_FEATURE_CHECK
87 ** AC_C_BIGENDIAN now supports universal binaries a la Mac OS X.
89 ** AC_C_RESTRICT now prefers to #define 'restrict' to a variant spelling
90 like '__restrict' if the variant spelling is available, as this is
91 more likely to work when mixing C and C++ code.
93 ** AC_CHECK_ALIGNOF's type argument T is now documented better: it must
94 be a string of tokens such that "T y;" is a valid member declaration
97 ** AC_CHECK_SIZEOF now accepts objects as well as types: the general rule
98 is that sizeof (X) works, then AC_CHECK_SIZEOF (X) should work.
100 ** AC_CHECK_TYPE and AC_CHECK_TYPES now work on any C type-name; formerly,
101 they did not work for function types. In C++, they now work on any
102 type-id that can be the operand of sizeof; this is similar to C,
103 except it excludes anonymous struct and union types. Formerly,
104 some (but not all) C++ types involving anonymous struct and union
105 were accepted, though this was not documented.
107 ** AC_CONFIG_LINKS now prefers to link against files in the build tree
108 if found, and it works to link against a file of the same name in
109 the source tree, even if both trees coincide.
111 ** AC_INIT no longer alters $@; regression introduced in 2.60.
113 ** AC_USE_SYSTEM_EXTENSIONS now defines _ALL_SOURCE for Interix platforms.
115 ** AS_HELP_STRING no longer underquotes its first argument; it also handles
116 the case where the first argument contains single-quoted commas.
117 For example, "AS_HELP_STRING([-a, [--arg[=foo]]], [bar])" produces:
118 " -a, --arg[=foo] bar"
119 Additionally, the macro now takes two additional arguments,
120 indent-column and wrap-column; these should not normally be needed,
121 but can be used to fine-tune how the output text is wrapped.
123 ** AC_PROG_INSTALL now requires an install program that can install multiple
124 files into a target directory.
126 ** The command 'autoconf -' now correctly processes a file from stdin.
128 ** 'autoreconf -m' now honors $MAKE.
130 ** For all of the directory arguments for 'configure', such as '--prefix'
131 or '--bindir', trailing slashes are stripped. As an example, if
132 tab completion in the user's shell appends trailing slashes, the
133 command './configure --prefix=/usr/' will still result in an
134 expanded libdir value of /usr/lib, not /usr//lib.
136 ** `configure --help=recursive' now works in read-only trees and from
137 unconfigured build trees.
139 ** If precious variables differ only in whitespace, then the cache consistency
140 check warns instead of fails, and reuses the old value.
142 ** AT_BANNER is now documented.
144 ** AT_SETUP now handles macro expansions properly when calculating line
147 ** Autotest now determines $srcdir correctly.
149 ** Testsuites built by autotest now accept a -C/--directory=DIR option
150 to adjust the working directory prior to creating files.
152 ** Autoconf now requires GNU M4 1.4.5 or later. Earlier versions of M4 have
153 a bug in macro tracing that interferes with the interaction between
154 Autoconf and Automake. GNU M4 1.4.11 or later is recommended. The
155 configure search for a working M4 is improved.
157 ** For portability with the eventual M4 2.0, macros should no longer use
158 anything larger than $9 to refer to arguments.
160 ** Documentation for m4sugar is improved.
162 - The following macros were previously available as undocumented
163 interfaces; the macros are now documented as stable interfaces.
165 __oline__ m4_assert m4_bmatch m4_bpatsubsts m4_car m4_case
166 m4_cdr m4_default m4_divert_once m4_divert_pop m4_divert_push
167 m4_divert_text m4_do m4_errprintn m4_fatal m4_flatten
168 m4_ifndef m4_ifset m4_ifval m4_ifvaln m4_location
169 m4_n m4_shiftn m4_strip m4_warn
171 - The following macros were previously available as undocumented
172 interfaces, but had bug fixes or semantic changes as part of this
173 release. Packages that relied on the undocumented behavior
174 should be analyzed to make sure they will still work with the
175 new documented behavior.
177 m4_cmp m4_list_cmp m4_join m4_map m4_map_sep m4_sign
178 m4_text_box m4_text_wrap m4_version_compare
180 - The m4_wrap macro used to have unspecified order, but now
181 guarantees FIFO order. m4_wrap_lifo was added to guarantee LIFO
184 - Packages using the undocumented m4sugar macro m4_PACKAGE_VERSION
185 should consider using the new AC_AUTOCONF_VERSION instead.
187 - m4sugar macros that are not documented in the manual are still
188 deemed experimental, and should not be used outside of Autoconf.
190 ** The m4sugar macros m4_append and m4_append_uniq, first documented in
191 2.60, have been fixed to treat both the string and the separator
192 arguments consistently with regards to quoting. Prior to this fix,
193 m4_append_uniq could mistakenly duplicate entries if the expansion
194 of the separator resulted in a different string (for example, if it
195 contained quotes, a comma, or a macro name). However, it means
196 that programs previously using
197 m4_append([name], [string], [[, ]])
198 are now using a four-character separator instead of the intended
199 comma and space. If you need portability to earlier versions of
200 Autoconf, you can insert the following snippet after AC_INIT but
201 before any other macro expansions, to enforce the new semantics:
202 m4_pushdef([m4_append], [m4_define([$1],
203 m4_ifdef([$1], [m4_defn([$1])[$3]])[$2])])
204 Additionally, m4_append_uniq now takes optional parameters that can
205 be used to take action depending on whether anything was appended,
206 and warns if a non-empty separator occurs within the string being
207 appended, since that can lead to duplicates.
209 ** The following m4sugar macros are new:
210 m4_append_uniq_w m4_apply m4_combine m4_cond m4_count
211 m4_dquote_elt m4_echo m4_expand m4_ignore m4_make_list m4_max
212 m4_min m4_newline m4_shift2 m4_shift3 m4_unquote m4_wrap_lifo
214 ** Warnings are now generated by default when an installer invokes
215 'configure' with an unknown --enable-* or --with-* option.
216 These warnings can be disabled with the new AC_DISABLE_OPTION_CHECKING
217 macro, or by invoking 'configure' with --disable-option-checking.
219 ** Existing obsolete macros
220 The documentation for the following macros is adjusted to make it
221 more clear that they have previously been marked obsolete, as their
222 functionality can be accomplished by other macros. We have no
223 current plans to remove them from Autoconf.
225 AC_ENABLE AC_STRUCT_ST_BLKSIZE AC_STRUCT_ST_RDEV AC_WITH
227 ** Newly obsolete macros
228 The following macros have been marked obsolete, as they only
229 perform a subset of AC_USE_SYSTEM_EXTENSIONS. We have no current
230 plans to remove them.
232 AC_AIX AC_GNU_SOURCE AC_ISC_POSIX AC_MINIX
234 ** AC_C_LONG_DOUBLE is obsolescent.
235 The documentation now says that AC_C_LONG_DOUBLE is obsolescent: it
236 tests for problems that are so old that it is no longer of
237 practical importance on current systems. New programs need not use
238 AC_C_LONG_DOUBLE. We have no current plans to remove it.
240 ** AC_DIAGNOSE, AC_WARNING, and AC_FATAL are obsolescent.
241 The documentation now favors the use of M4sugar macros m4_warn and
242 m4_fatal, since the naming makes it more obvious that the
243 diagnostics are associated with M4 expansion (ie. when running
244 `autoconf'), and offers less confusion with the AC_MSG_ERROR,
245 AC_MSG_FAILURE, and AC_MSG_WARN macros which manage diagnostics
246 when running `configure'. We have no current plans to remove these
250 * Major changes in Autoconf 2.61a (2006-12-11)
252 ** AC_FUNC_FSEEKO was broken in 2.61; it didn't make fseeko and ftello visible
253 on many platforms. This has been fixed.
255 ** AC_FUNC_SETVBUF_REVERSED is now obsolete. It is still defined for backward
256 compatibility but it does nothing. The macro was already
257 obsolescent, as the last systems to have the problem were those
258 based on SVR2, which became obsolete in 1987. The macro had bugs
259 on some modern systems and could no longer be maintained reliably
260 due to lack of ancient systems to test it on.
262 ** config.status now uses awk instead of sed for most substitutions, for speed.
264 - As a side effect multi-line values of substituted variables no
265 longer have a small limit in total size, though for portability
266 each line should not exceed the POSIX length limit for text lines.
268 - It is now documented that Makefile.in should not contain
269 overlapping variable occurrences, e.g., @VAR1@VAR2@.
270 Autoconf's behavior was always iffy in such cases, and the
271 awk implementation has changed the behavior.
273 ** Many uses of 'echo' have been rewritten so that Autoconf-generated
274 scripts have fewer problems with strings or file names containing
275 embedded special characters such as backslash or leading "-". This
276 was implemented by using `printf '%s\n' "$foo"' instead of `echo
277 "$foo"' when printf works. Due to the implementation technique
278 used, Autoconf-generated scripts now run considerably more slowly
279 on ancient implementations lacking printf. However, this should
280 not be a problem, since Autoconf-generated scripts in practice
281 invariably find a more-modern shell these days.
284 * Major changes in Autoconf 2.61 (2006-11-17)
286 ** New macros AC_C_FLEXIBLE_ARRAY_MEMBER, AC_C_VARARRAYS.
288 ** AC_ARG_ENABLE and AC_ARG_WITH now allow '.' in feature and package names.
291 * Major changes in Autoconf 2.60b (2006-10-22)
294 Autoconf-generated shell scripts no longer export BIN_SH, due to
295 configuration hassles with this. Installers who need BIN_SH in
296 their environment should set it before invoking 'configure' and
297 'make'. As far as we know, this affects only Unixware installations.
299 ** Obsolescent macros
300 The documentation now says that the following macros are obsolescent,
301 as they are superseded by Gnulib:
303 AC_FUNC_FNMATCH AC_FUNC_FNMATCH_GNU AC_FUNC_GETLOADVG AC_REPLACE_FNMATCH
305 New programs should use the Gnulib counterparts of these macros.
306 We have no current plans to remove them from Autoconf.
308 ** AC_COMPUTE_INT no longer caches or reports results.
310 ** AC_CHECK_DECL now also works with aggregate objects.
312 ** AC_USE_SYSTEM_EXTENSIONS now defines _TANDEM_SOURCE for NonStop platforms.
314 ** GNU M4 1.4.7 or later is now recommended.
317 New M4sugar macro, which is more secure than the POSIX M4 maketemp.
320 Now an alias for m4_mkstemp.
322 * Major changes in Autoconf 2.60a (2006-08-25)
324 ** GNU M4 1.4.6 or later is now recommended.
326 ** The check for C99 now tests for varargs macros, as documented.
327 It also tests that the preprocessor supports 64-bit integers.
329 ** Autoconf now uses constructs like "#ifdef HAVE_STDLIB_H" rather than
330 "#if HAVE_STDLIB_H", so that it now works with "gcc -Wundef -Werror".
332 ** The functionality of the undocumented _AC_COMPUTE_INT is now provided
333 by a public and documented macro, AC_COMPUTE_INT. The parameters to the
334 two macros are different, so autoupdate will not change the old private name
335 to the new one. _AC_COMPUTE_INT may be removed in a future release.
337 ** AC_TYPE_LONG_LONG_INT and AC_TYPE_UNSIGNED_LONG_LONG_INT now require
338 that long long types be at least 64 bits wide, as C99 and tradition
339 requires. Formerly, they accepted implementations of any width.
342 * Major changes in Autoconf 2.60
344 Released 2006-06-23, by Ralf Wildenhues.
346 ** Autoconf no longer depends on whether m4wrap is FIFO (as Posix requires)
347 or LIFO (as in GNU M4 1.4.x). GNU M4 2.0 is expected to conform to Posix
348 here, so m4wrap/m4_wrap users should no longer depend on LIFO behavior.
350 ** Provide a way to turn off warnings about the changed directory variables.
352 * Major changes in Autoconf 2.59d
354 Released 2006-06-05, by Ralf Wildenhues.
356 ** GNU make now recommended for VPATH builds
357 INSTALL now suggests VPATH builds (e.g., "sh ../srcdir/configure")
358 only if you use GNU make. In practice, other 'make' implementations
359 have too many subtle incompatibilities in their support for VPATH.
360 Many packages (including Autoconf itself) are portable to other
361 'make' implementations, but some packages are not, and recommending
362 GNU make keeps the installation instructions simpler.
364 ** Even more safety checks for the new Directory variables:
365 Warn about suspicious `${datarootdir}' found in config files output.
367 ** AC_TRY_COMMAND, AC_TRY_EVAL, ac_config_guess, ac_config_sub, ac_configure
368 These never-documented macros and variables have been marked with
369 comments saying that they may be removed in a future release,
370 because their use can lead to unintended code being executed.
371 If you need functionality that only these macros or variables
372 currently supply, please write bug-autoconf@gnu.org.
374 ** AC_SUBST, AC_DEFINE
375 Literal arguments to these are passed to m4_pattern_allow now.
378 Passing 'ac_cv_prog_cc_stdc=no' to 'configure' now sets ac_cv_prog_cc_c99
379 and ac_cv_prog_cc_c89 to 'no' as well, for backward compatibility with
380 obsolete K&R tests in the Automake test suite.
389 Now more robust with special characters in file names, or when
390 multiple processes create the same directory at the same time.
392 ** Obsolescent macros
393 The documentation now says that the following macros are obsolescent:
394 they test for problems that are so old that they are no longer of
395 practical importance on current systems.
397 AC_C_BACKSLASH_A AC_FUNC_MEMCMP AC_HEADER_DIRENT
398 AC_C_CONST AC_FUNC_SELECT_ARGTYPES AC_HEADER_STAT
399 AC_C_PROTOTYPES AC_FUNC_SETPGRP AC_HEADER_STDC
400 AC_C_STRINGIZE AC_FUNC_SETVBUF_REVERSED AC_HEADER_SYS_WAIT
401 AC_C_VOLATILE AC_FUNC_STAT AC_HEADER_TIME
402 AC_FUNC_CLOSEDIR_VOID AC_FUNC_STRFTIME AC_ISC_POSIX
403 AC_FUNC_GETPGRP AC_FUNC_UTIME_NULL AC_PROG_GCC_TRADITIONAL
404 AC_FUNC_LSTAT AC_FUNC_VPRINTF AC_STRUCT_TM
406 New programs need not use these macros. We have no current plans to
410 For compatibility with future Libtool 2.0, autoreconf will invoke
411 libtoolize with the option `--ltdl' now, if LT_CONFIG_LTDL_DIR is
414 * Major changes in Autoconf 2.59c
416 Released 2006-04-12, by Ralf Wildenhues.
418 ** The configure command now redirects standard input from /dev/null,
419 to help avoid problems with subsidiary commands that might mistakenly
420 read standard input. AS_ORIGINAL_STDIN_FD points to the original
421 standard input before this redirection, if you really want configure to
422 read from standard input.
424 ** Directory variables adjusted to recent changes in the GNU Coding Standards.
425 The following directory variables are new:
427 datarootdir read-only architecture-independent data root [PREFIX/share]
428 localedir locale-specific message catalogs [DATAROOTDIR/locale]
429 docdir documentation root [DATAROOTDIR/doc/PACKAGE]
430 htmldir html documentation [DOCDIR]
431 dvidir dvi documentation [DOCDIR]
432 pdfdir pdf documentation [DOCDIR]
433 psdir ps documentation [DOCDIR]
435 The following variables have new default values:
437 datadir read-only architecture-independent data [DATAROOTDIR]
438 infodir info documentation [DATAROOTDIR/info]
439 mandir man documentation [DATAROOTDIR/man]
441 This means that if you use any of `@datadir@', `@infodir@', or
442 `@mandir@' in a file, you will have to ensure `${datarootdir}' is
443 defined in this file. As a temporary measure, if any of those are
444 found but no mention of `datarootdir', the substitutions will be
445 replaced with values that do not contain `${datarootdir}', and a
446 warning will be issued.
448 ** @top_builddir@ is now a dir name: it is always nonempty and doesn't have
449 a trailing slash. Similar change will be made to ac_top_builddir in a
450 future release; the old style value, which matches (../)*, is (and will
451 continue to be) available as ac_top_build_prefix.
454 New macro to check for support of 'typeof' syntax a la GNU C.
456 ** AC_CHECK_DECLS_ONCE, AC_CHECK_FUNCS_ONCE, AC_CHECK_HEADERS_ONCE
457 New "once-only" variants of commonly-used macros, to make 'configure'
458 smaller and faster in common cases.
461 New macro to check for strtold with C99 semantics.
464 New macro that lets builder disable assertions at 'configure'-time.
467 Now checks for X11/Xlib.h and XrmInitialize (X proper) rather than
468 X11/Intrinsic.h and XtMalloc (Xt).
470 ** AC_PRESERVE_HELP_ORDER
471 New macro that causes `configure' to display help strings for AC_ARG_ENABLE
472 and AC_ARG_WITH arguments in one region, in the order defined. The default
473 behavior is to group options of each classes separately.
475 ** AC_PROG_CC, AC_PROG_CXX
476 No longer automatically arrange to declare the 'exit' function of C,
477 when a C++ compiler is used. Standard Autoconf macros no longer use
478 'exit', so this is no longer an issue for them. If you use C++, and
479 want to call 'exit', you'll have to arrange for its declaration
480 yourself. But we now suggest you return from 'main' instead.
482 ** AC_PROG_CC_C89, AC_PROG_CC_C99
483 New macros for ISO C99 support. AC_PROG_CC_C89 and AC_PROG_CC_C99
484 check for ANSI C89 and ISO C99 support respectively.
487 Has been unobsoleted, and will check if the compiler supports ISO
488 C99, falling back to ANSI C89 if not. ac_cv_prog_cc_stdc is
489 retained for backwards compatibility, assuming the value of
490 ac_cv_prog_cc_c99 or ac_cv_prog_cc_c89 (whichever is valid, in
493 ** AC_STRUCT_DIRENT_D_INO, AC_STRUCT_DIRENT_D_TYPE
494 New macros for checking commonly-used members of struct dirent.
497 The substituted value can now contain newlines.
500 The substitution now occurs only when @variable@ is on a line by itself,
501 optionally surrounded by spaces and tabs. The whole line is replaced.
503 ** AC_TYPE_LONG_DOUBLE, AC_TYPE_LONG_DOUBLE_WIDER
504 New macros to check for long double, and whether it is wider than double.
505 The old macro AC_C_TYPE_LONG_DOUBLE has been marked as obsolete;
506 applications should switch to the new macro.
508 ** AC_TYPE_INT8_T, AC_TYPE_INT16_T, AC_TYPE_INT32_T, AC_TYPE_INT64_T,
509 AC_TYPE_INTMAX_T, AC_TYPE_INTPTR_T, AC_TYPE_LONG_LONG_INT, AC_TYPE_SSIZE_T,
510 AC_TYPE_UINT8_T, AC_TYPE_UINT16_T, AC_TYPE_UINT32_T, AC_TYPE_UINT64_T,
511 AC_TYPE_UINTMAX_T, AC_TYPE_UINTPTR_T, AC_TYPE_UNSIGNED_LONG_LONG_INT
512 New macros to check for C99 and POSIX types.
514 ** AC_USE_SYSTEM_EXTENSIONS
515 New macro to enable extensions to Posix.
518 New macro which is defined to the name of the first declared config header
519 or undefined if no config headers have been declared yet.
522 The macro correctly handles quadrigraphs now.
524 ** AS_BOURNE_COMPATIBLE, AS_SHELL_SANITIZE, AS_CASE
525 These macros are new or published now.
528 New macro for copyright notices in testsuite files.
530 ** ALLOCA, LIBOBJS, LTLIBOBJS
531 Object names added to these variables are now prefixed with `${LIBOBJDIR}',
532 as in `${LIBOBJDIR}alloca.o'. LIBOBJDIR is meant to be defined from
533 `Makefile.in' in case the object files lie in a different directory.
534 The LIBOBJDIR feature is experimental.
537 Supports --no-recursive now.
539 ** New macros to support Erlang/OTP.
540 New macros for configuring paths to Erlang tools and libraries:
541 AC_ERLANG_PATH_ERLC, AC_ERLANG_NEED_ERLC, AC_ERLANG_PATH_ERL,
542 AC_ERLANG_NEED_ERL, AC_ERLANG_CHECK_LIB, AC_ERLANG_SUBST_ROOT_DIR,
543 AC_ERLANG_SUBST_LIB_DIR.
545 New macros for configuring installation of Erlang libraries:
546 AC_ERLANG_SUBST_INSTALL_LIB_DIR, AC_ERLANG_SUBST_INSTALL_LIB_SUBDIR.
548 ** The manual now mentions Gnulib more prominently.
550 ** New macros to support Objective C.
551 AC_PROG_OBJC, AC_PROG_OBJCPP.
553 * Major changes in Autoconf 2.59b
555 Released 2004-08-20, by Paul Eggert.
558 New macro that computes the default alignment of a type.
560 ** AC_CHECK_TOOL, AC_PATH_TOOL, AC_CHECK_TOOLS
561 When cross-compiling, these macros will give a warning if the tool
562 is not prefixed. In the future, unprefixed cross tools will not
563 be detected; please consult the info documentation for information
564 about the reason of this change.
566 ** AC_CHECK_TARGET_TOOL, AC_PATH_TARGET_TOOL, AC_CHECK_TARGET_TOOLS
567 New macros that detect programs whose name is prefixed with the
568 target type, if the build type and target type are different.
570 ** AC_REQUIRE_AUX_FILE
571 New trace macro that declares expected auxiliary files.
574 New macro that tests for a grep program that accepts as a long a line
577 ** AC_PROG_EGREP, AC_PROG_FGREP
578 These macros now require AC_PROG_GREP, and try EGREP="$GREP -E" and
579 FGREP="$GREP -F" respectively if possible, or else run a path search for
580 a program that accepts as long a line as possible.
583 New macro that tests for a sed program that truncates as few characters
586 * Major changes in Autoconf 2.59
588 Released 2003-11-04, by Akim Demaille
590 ** ac_abs_builddir etc.
591 Absolute file names were actually relative in 2.58.
593 * Major changes in Autoconf 2.58
595 Released 2003-11-04, by Akim Demaille
598 core.* files are no longer removed, as they may be valid user files.
600 ** autoreconf and auxiliary directory
601 Autoreconf creates the auxiliary directory if needed. This is
602 especially useful for initial "bootstrapping" of fresh CVS checkouts.
604 ** AC_CONFIG_MACRO_DIR
605 Use this macro to declare the directory for local M4 macros for aclocal.
608 No longer includes twice the same file in LIBOBJS if invoked
611 ** AC_CONFIG_COMMANDS
612 The directory for its first argument is automatically created. For
615 AC_CONFIG_COMMANDS([src/modules.hh], [...])
617 $top_builddir/src/ is created if needed.
619 ** Autotest and local.at
620 The optional file local.at is always included in Autotest test suites.
623 The warnings are always issued, including with cached runs.
624 This became a significant problem since aclocal and automake can
625 run autoconf behind the scene.
627 ** autoheader warnings
628 The warnings of autoheader can be turned off, using --warning.
629 For instance, -Wno-obsolete disables the complaints about acconfig.h
630 and other deprecated constructs.
633 AC_C_RESTRICT, AC_INCLUDES_DEFAULT, AC_LANG_ASSERT, AC_LANG_WERROR,
636 ** AC_DECL_SYS_SIGLIST
640 Now checks that mktime is the inverse of localtime.
642 ** Improve DJGPP portability
643 The Autoconf tools and configure behave better under DJGPP.
645 ** Present But Cannot Be Compiled
646 New FAQ section dedicated to the mystic
648 configure: WARNING: pi.h: present but cannot be compiled
649 configure: WARNING: pi.h: check for missing prerequisite headers?
650 configure: WARNING: pi.h: proceeding with the preprocessor's result
653 ** Concurrent executions of autom4te
654 autom4te now locks its internal files, which enables concurrent
655 executions of autom4te, likely to happen if automake, autoconf,
656 autoheader etc. are run simultaneously.
659 Use of Libtool 1.5 and higher is encouraged. Compatibility with
660 Libtool pre-1.4 is not checked.
663 Testsuites no longer rerun failed tests in verbose mode; instead,
664 failures are logged while the test is run.
666 In addition, expected failures can be marked as such.
668 * Major changes in Autoconf 2.57
670 Released 2002-12-03 by Paul Eggert.
672 Bug fixes for problems with AIX linker, with freestanding C compilers,
673 with GNU M4 limitations, and with obsolete copies of GNU documents.
675 The Free Documentation License has been upgraded from 1.1 to 1.2.
677 * Major changes in Autoconf 2.56
679 Released 2002-11-15 by Akim Demaille.
681 One packaging problem fixed (config/install-sh was not executable).
683 * Major changes in Autoconf 2.55
685 Released 2002-11-14 by Akim Demaille.
689 Have your configure.ac checked by autoscan ("autoscan").
690 Try the warning options ("autoreconf -fv -Wall").
694 - AC_CHECK_HEADER, AC_CHECK_HEADERS
695 More information on proper use.
697 - Writing Test Programs
699 This sections explains how to write good test sources to use with
700 AC_COMPILE_IFELSE etc. It documents AC_LANG_PROGRAM and so forth.
702 - AC_FOO_IFELSE vs. AC_TRY_FOO
704 Explains why Autoconf moves from AC_TRY_COMPILE etc. to
705 AC_COMPILE_IFELSE and AC_LANG_PROGRAM etc.
709 - Is more robust to different Gettext installations.
711 - Produces messages (when --verbose) to be understood by Emacs'
714 - Supports -W/--warnings.
717 Once the GNU Build System reinstalled, run `./config.status
718 --recheck && ./config.status && make' if possible.
722 - Supports --cache, and --no-cache.
724 - ~/.autom4te.cfg makes it possible to disable the caching mechanism
725 (autom4te.cache). See `Customizing autom4te' in the documentation.
732 Support for the obsoleted options -m, --macrodir, -l, --localdir is
733 dropped in favor of the safer --include/--prepend-include scheme.
738 AC_COMPILER_IFELSE, AC_FUNC_MBRTOWC, AC_HEADER_STDBOOL,
739 AC_LANG_CONFTEST, AC_LANG_SOURCE, AC_LANG_PROGRAM, AC_LANG_CALL,
740 AC_LANG_FUNC_TRY_LINK, AC_MSG_FAILURE, AC_PREPROC_IFELSE.
743 Obsoleted macros are kept for Autoconf backward compatibility, but
744 should be avoided in configure.ac. Running autoupdate is advised.
747 - AC_DEFINE/AC_DEFINE_UNQUOTED
749 We have to stop using the old compatibility scheme --that tried to
750 avoid useless backslashes-- because Libtool 1.4.3 contains a
752 AC_DEFINE([error_t], [int],
753 [Define to a type to use for \`error_t' if it is not
754 otherwise available.])
756 We have to quote the single quotes and backslashes with \. The old
757 compatibility scheme saw that ` was backslashed, and therefore did
758 not quote the single quote... Failure. Hence, Autoconf 2.54 is not
759 compatible with Libtool. Autoconf 2.55 is, but in some cases might
760 produce more \ than wanted.
762 Please, note that in the future the same problem will happen with
763 AC_MSG_*: use `autoreconf -f -Wall'.
767 - Portability of the Autoconf package to Solaris.
769 - Spurious warnings caused by config.status.
770 This bug is benign, but painful: on some systems (typically
771 FreeBSD), warnings such as:
773 config.status: creating Makefile
774 mv: Makefile: set owner/group (was: 1357/0): Operation not permitted
776 could be issued. This is fixed.
779 Simultaneous executions of config.status are possible again.
781 - Precious variables accumulation
783 config.status could stack several copies of the precious variables
787 ** Plans for later versions
791 The compatibility hooks with the old scheme will be completely
792 removed. Please, advice/use `--build', `--host', and `--target'
795 - AC_CHECK_HEADER, AC_CHECK_HEADERS
797 The tests will be stricter, please make sure your invocations are
802 Shell functions will gradually be introduced, probably starting with
803 Autotest. If you know machines which are in use that you suspect
804 *not* to support shell functions, please run the test suite of
805 Autoconf 2.55 on it, and report the results to
806 bug-autoconf@gnu.org.
810 Special characters in AC_MSG_* need not be quoted. Currently,
811 Autoconf has heuristics to decide when a string is escaped, or has
812 to be escaped. This scheme is fragile, and will be removed; the
813 only risk is uglified messages. Please, run `autoreconf -f -Wall'
814 to find occurrences that will be affected.
816 * Major changes in Autoconf 2.54
818 Released 2002-09-13 by Akim Demaille.
822 - autoreconf no longer changes the version of the gettext/po/intl
823 support files. It now adds the files the correspond to the
824 AM_GNU_GETTEXT_VERSION declared in configure.ac.
826 Warning: It now relies on the 'autopoint' program, which is part
827 of GNU gettext 0.11.4 and newer.
829 Please note that you need to have a GNU gettext version that
830 corresponds at least to the AM_GNU_GETTEXT_VERSION declared
831 in configure.ac. You can upgrade to newer GNU gettext versions,
832 though, without needing to change configure.ac.
834 - The -I DIR or --include=DIR option now appends DIR to the include path
835 instead of prepending; this is for consistency with other GNU tools.
836 The new -B DIR or --prepend-include=DIR option has the old behavior.
841 Now handles all the gory details about LIBOBJS and LTLIBOBJS.
842 Please, remove lines such as
844 # This is necessary so that .o files in LIBOBJS are also
845 # built via the ANSI2KNR-filtering rules.
846 LIBOBJS=`echo $LIBOBJS|sed 's/\.o /\$U.o /g;s/\.o$/\$U.o/'`
848 and read the `AC_LIBOBJ vs LIBOBJS' section. Do not define U in
849 your Makefiles either.
851 - AC_CONFIG_LINKS now makes copies if it can't make links.
853 - AC_FUNC_FNMATCH now tests only for POSIX compatibility, reverting to
854 Autoconf 2.13 behavior. The new macro AC_FUNC_FNMATCH_GNU also
855 tests for GNU extensions to fnmatch, and replaces fnmatch if needed.
857 - AC_FUNC_SETVBUF_REVERSED no longer fails when cross-compiling.
859 - AC_PROG_CC_STDC is integrated into AC_PROG_CC.
861 - AC_PROG_F77 default search no longer includes cf77 and cfg77.
865 AC_C_BACKSLASH_A, AC_CONFIG_LIBOBJ_DIR, AC_GNU_SOURCE,
866 AC_PROG_EGREP, AC_PROG_FGREP, AC_REPLACE_FNMATCH,
867 AC_FUNC_FNMATCH_GNU, AC_FUNC_REALLOC, AC_TYPE_MBSTATE_T.
870 looks for getloadavg.c in the CONFIG_LIBOBJ_DIR.
873 Now defines HAVE_MALLOC to 0 if `malloc' does not work, and asks
874 for an AC_LIBOBJ replacement.
878 - Spurious complaints from `m4_bmatch' about invalid regular
879 expressions are suppressed.
881 - Empty top_builddirs are properly handled.
883 - AC_CHECK_MEMBER works correctly when the member is an aggregate.
886 Now colon in the optional path arguments are properly handled.
888 ** Improved portability
890 - Both Autoconf the package, and the scripts it produces, should run
891 more reliably with Zsh. Bear in mind it is the default Bourne shell
894 - Autoconf and the scripts it produces no longer assume the existence of
895 the obsolescent commands egrep and fgrep.
899 - Limitations of Make
903 The GNATS base moved to
904 http://bugs.gnu.org/cgi-bin/gnatsweb.pl?database=autoconf
905 (It is no longer available, though.)
910 Now contains the list of ouput variables and files (AC_SUBST,
913 * Major changes in Autoconf 2.53
915 Released 2002-03-08 by Akim Demaille.
919 Perl 5.005_03 or later is required: autom4te is written in Perl and is
920 needed by autoconf. autoheader, autoreconf, ifnames, and autoscan are
926 Argument requirements, output variables, defined macros.
927 - M4sugar, M4sh, Autotest
929 - Double quoting macros
930 AC_TRY_CPP, AC_TRY_COMPILE, AC_TRY_LINK and AC_TRY_RUN.
932 The Autoconf manual is now distributed under the terms of the GNU FDL.
933 - Section `Hosts and Cross-Compilation'
934 Explains the rationale for the 2.5x changes in the cross-compilation
935 chain, and in the relationships between build, host, and target
937 Emphasizes that `cross-compilation' == `--host is given'.
938 If you are working on compilers etc., be sure to read this section.
939 - Section `AC_LIBOBJ vs. LIBOBJS'
940 Explains why assigning LIBOBJS directly is now an error.
941 Details how to update the code.
946 Now used instead of hard coded line numbers.
947 This eases the comparison of `configure's, and diminishes the
948 pressure over control version archives.
949 Automatic replacement for shells that don't support this feature.
950 - New output variables
951 @builddir@, @top_builddir@, @abs_srcdir@, @abs_top_srcdir@, @abs_builddir@,
956 Autoconf and Autotest modes are provided.
961 New, used by the Autoconf suite to cache and speed up most processing.
963 Supported by autom4te, autoconf and autoheader.
965 Replaces --autoconf-dir and --localdir in autoconf, autoheader,
966 autoupdate, and autoreconf.
968 No longer passes --cygnus, --foreign, --gnits, --gnu, --include-deps:
969 automake options are to be given via AUTOMAKE_OPTIONS.
971 Runs gettextize and libtoolize when appropriate.
973 --m4dir is no longer supported.
975 Now runs only in the specified directories, defaulting to `.',
976 but understands AC_CONFIG_SUBDIRS for dependent directories.
977 Before, it used to run on all the `configure.ac' found in the
979 Independent packages are properly updated.
983 - The top level $prefix is propagated to the AC_CONFIG_SUBDIRS configures.
985 Under the user pressure, $? is finally available. Probably a mistake.
986 - AC_F77_LIBRARY_LDFLAGS now supports the HP/UX f90 compiler.
987 - Precious variables accumulation
988 config.status could stack several copies of the precious variables
990 - AC_PATH_PROG and family.
991 Works properly when given a literal path.
993 Somewhere since 2.13, the result had been reversed.
997 - AC_C_BIGENDIAN supports the cross-compiling case.
998 - AC_C_BIGENDIAN accepts ACTION-IF-TRUE, ACTION-IF-FALSE, and
999 ACTION-IF-UNKNOWN arguments. All are facultative, and the default
1000 for ACTION-IF-TRUE is to define WORDS_BIGENDIAN like AC_C_BIGENDIAN
1002 - AC_C_LONG_DOUBLE now succeeds only if `long double' has more range or
1003 precision than `double'.
1008 It now defines the preprocessor symbols PACKAGE_NAME,
1009 PACKAGE_TARNAME, PACKAGE_VERSION, PACKAGE_STRING, and
1013 Admits a fourth optional parameter: the tar name.
1015 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS.
1016 Provide the user with srcdir, ac_srcdir, ac_top_srcdir, ac_builddir,
1017 ac_top_builddir, ac_abs_srcdir, ac_abs_top_srcdir, ac_abs_builddir,
1018 ac_abs_top_builddir.
1020 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS and AC_OUTPUT.
1021 Are much less expensive when using long lists of files.
1024 Works with shell variables, and non alphanumeric names.
1028 - AC_FUNC_STRERROR_R now sets STRERROR_R_CHAR_P, not HAVE_WORKING_STRERROR_R,
1029 because POSIX 1003.1-200x draft 7 says strerror_r returns int, not char *.
1031 - AC_FUNC_STRTOD substitutes POW_LIB.
1036 * Major changes in Autoconf 2.52
1038 Released 2001-07-18 by Akim Demaille.
1043 This feature was present in autoconf 2.50 but was not documented.
1044 For example, `@<:@' is translated to `[' just before output. This
1045 is useful when writing strings that contain unbalanced quotes, or
1046 other hard-to-quote constructs.
1047 - m4_pattern_forbid, m4_pattern_allow
1048 - Tips for upgrading from 2.13.
1049 - Using autoscan to maintain a configure.ac.
1052 - Now include stdint.h.
1053 - sys/types.h and sys/stat.h are guarded.
1054 - strings.h is included if available, and not conflicting with string.h.
1057 - The test suite is more robust and presents less false failures.
1058 - Invocation of GNU M4 now robust to POSIXLY_CORRECT.
1059 - configure accepts --prefix='' again.
1060 - AC_CHECK_LIB works properly when its first argument is not a
1062 - HAVE_INTTYPES_H is defined only if not conflicting with sys/types.h.
1063 - build_, host_, and target_alias are AC_SUBST as in 2.13.
1064 - AC_ARG_VAR properly propagates precious variables inherited from the
1065 environment to ./config.status.
1066 - Using --program-suffix/--program-prefix is portable.
1067 - Failures to detect the default compiler's output extension are less
1069 - `config.status foo' works properly when `foo' depends on variables
1070 set in an AC_CONFIG_THING INIT-CMD.
1071 - autoheader is more robust to broken input.
1072 - Fixed Fortran name-mangling and link tests on a number of systems,
1073 e.g. NetBSD; see AC_F77_DUMMY_MAIN, below.
1076 - AC_CHECK_HEADER and AC_CHECK_HEADERS support a fourth argument to
1077 specify pre-includes. In this case, the headers are compiled with
1078 cc, not merely preprocessed by cpp. Therefore it is the _usability_
1079 of a header which is checked for, not just its availability.
1080 - AC_ARG_VAR refuses to run configure when precious variables have
1082 - Versions of compilers are dumped in the logs.
1083 - AC_CHECK_TYPE recognizes use of `foo_t' as a replacement type.
1086 - AC_PATH_XTRA only adds -ldnet to $LIBS if it's needed to link.
1087 - AC_FUNC_WAIT3 and AC_SYS_RESTARTABLE_SYSCALLS are obsoleted.
1088 - AM_FUNC_ERROR_AT_LINE, AM_FUNC_FNMATCH, AM_FUNC_MKTIME,
1089 AM_FUNC_OBSTACK, and AM_FUNC_STRTOD are now activated.
1090 Be sure to read `Upgrading from Version 2.13' to understand why
1091 running `autoupdate' is needed.
1092 - AC_F77_DUMMY_MAIN, AC_F77_MAIN: new macros to detect whether
1093 a main-like routine is required/possible when linking C/C++ with
1094 Fortran. Users of e.g. AC_F77_WRAPPERS should be aware of these.
1095 - AC_FUNC_GETPGRG behaves better when cross-compiling.
1097 * Major changes in Autoconf 2.51
1098 There was no release of Autoconf 2.51 since some packagers had used
1099 this version number without permission to ship intermediary versions
1100 of 2.50. The version was skipped to avoid confusion.
1102 * Major changes in Autoconf 2.50
1104 Released 2001-05-21 by Akim Demaille.
1106 ** Lots of bug fixes
1107 There have been far too many to enumerate them here. Check out
1108 ChangeLog if you really want to know more.
1110 ** Improved documentation
1111 In particular, portability issues are better covered.
1114 All the standard GNU Makefile targets are supported. The layout has
1115 changed: m4/ holds the M4 extensions Autoconf needs for its
1116 configuration, doc/ contains the documentation, and tests/ contains
1119 ** Man pages are provided
1120 For autoconf, autoreconf, autoupdate, autoheader, autoscan, ifnames,
1121 config.guess, config.sub.
1125 Provides a safe and powerful means to trace the macro uses. This
1126 provide the parsing layer for tools which need to `study'
1130 Specify what category of warnings should be enabled.
1132 - When recursing into subdirectories, try for configure.gnu before
1133 configure to adapt for packages not using autoconf on case-insensitive
1137 More errors are now caught (circular AC_REQUIRE dependencies,
1138 AC_DEFINE in the action part of an AC_CACHE_CHECK, too many pops
1139 etc.). In addition, their location and call stack are given.
1142 autoupdate is much more powerful, and is able to provide the glue code
1143 which might be needed to move from an old macro to its newer
1146 You are strongly encouraged to use it to modernize both your
1147 `configure.in' and your .m4 extension files.
1150 The internal machinery of autoheader has completely changed. As a
1151 result, using `acconfig.h' should be considered to be obsoleted, and
1152 you are encouraged to get rid of it using the AH macros.
1157 ** Fortran 77 compilers
1158 Globally, the support for Fortran 77 is considerably improved.
1160 Support for automatically determining a Fortran 77 compiler's
1161 name-mangling scheme. New CPP macros F77_FUNC and F77_FUNC_ are
1162 provided to wrap C/C++ identifiers, thus making it easier and more
1163 transparent for C/C++ to call Fortran 77 routines, and Fortran 77 to
1164 call C/C++ routines. See the Texinfo documentation for details.
1167 The test suite no longer uses DejaGNU. It should be easy to submit
1168 test cases in this new framework.
1171 - --help, --help=long, -hl
1172 no longer dumps useless items.
1174 lists only specific options.
1175 - --help=recursive, -hr
1176 displays the help of all the embedded packages.
1177 - Remembers environment variables when reconfiguring.
1178 The previous scheme to set envvar before running configure was
1180 what prevented configure from remembering the environment in which
1181 it was run, therefore --recheck was run in an inconsistent
1182 environment. Now, one should run
1184 and then --recheck will work properly. Variables declared with
1185 AC_ARG_VAR are also preserved.
1187 $build defaults to `config.guess`, $host to $build, and then $target
1189 Cross-compilation is a global status of the package, it no longer
1190 depends upon the current language.
1191 Cross compilation is enabled iff the user specified `--host'.
1192 `configure' now fails if it can't run the executables it compiles,
1193 unless cross-compilation is enabled.
1195 The cache file is disabled by default. The new options
1196 `--config-cache', `-C' set the cache to `config.cache'.
1200 Much faster on most architectures.
1201 - concurrent executions
1202 It is safe to use `make -j' with config.status.
1203 - human interface improved
1204 It is possible to invoke
1205 ./config.status foobar
1206 instead of the former form (still valid)
1207 CONFIG_COMMANDS= CONFIG_HEADERS= CONFIG_LINKS= \
1208 CONFIG_FILES=foobar:foo.in:bar.in \
1210 The same holds for configuration headers and links.
1211 You can instantiate unknown files and headers:
1212 ./config.status --header foo.h:foo.h.in --file bar:baz
1213 - has a useful --help
1214 - accepts special file name "-" for stdin/stdout
1219 Specify additional copyright information.
1222 Now expects the identity of the package as argument.
1226 Most macros, if not all, now strictly follow the `one quotation
1227 level' rule. This results in a more predictable expansion.
1230 A sly bug in the AC_REQUIRE machinery, which could produce incorrect
1231 configure scripts, was fixed by Axel Thimm.
1235 Document and ask for the registration of an envvar.
1238 Specifies the file which `configure' should look for when trying to
1239 find the source tree (used to be handled by AC_INIT).
1241 - AC_CONFIG_COMMANDS
1242 To add new actions to config.status. Should be used instead of
1246 Replaces AC_LINK_FILES.
1248 - AC_CONFIG_HEADERS, AC_CONFIG_COMMANDS, AC_CONFIG_SUBDIRS,
1249 AC_CONFIG_LINKS, and AC_CONFIG_FILES
1250 They now obey sh: you should no longer use shell variables as
1251 argument. Instead of
1253 test "$package_foo_enabled" = yes && $my_subdirs="$my_subdirs foo"
1254 AC_CONFIG_SUBDIRS($my_subdirs)
1258 if test "$package_foo_enabled" = yes; then
1259 AC_CONFIG_SUBDIRS(foo)
1263 To format an Autoconf macro's help string so that it looks pretty
1264 when the user executes `configure --help'.
1267 ** Generic Test Macros
1269 The interface of the AC_CHECK families of macros (decl, header,
1270 type, member, func) is now uniform. They support the same set of
1273 - AC_CHECK_DECL, AC_CHECK_DECLS
1274 To check whether a symbol is declared.
1276 - AC_CHECK_SIZEOF, AC_C_CHAR_UNSIGNED.
1277 No longer need a cross-compilation default.
1280 The test it performs is much more robust than previously, and makes
1281 it possible to test builtin types in addition to typedefs.
1282 It is now schizophrenic:
1283 - AC_CHECK_TYPE(TYPE, REPLACEMENT)
1284 remains for backward compatibility, but its use is discouraged.
1285 - AC_CHECK_TYPE(TYPE, IF-FOUND, IF-NOT-FOUND, INCLUDES)
1286 behaves exactly like the other AC_CHECK macros.
1289 Checks whether given types are supported by the system.
1291 - AC_CHECK_MEMBER, AC_CHECK_MEMBERS
1292 Check for given members in aggregates (e.g., pw_gecos in struct
1296 Checks if the compiler supports ISO C, included when needs special
1300 Checking whether the preprocessor indicates missing includes by the
1301 error code. stderr is checked by AC_TRY_CPP only as a fallback.
1304 Takes a language as argument and replaces AC_LANG_C,
1305 AC_LANG_CPLUSPLUS and AC_LANG_FORTRAN77.
1307 - AC_LANG_PUSH, AC_LANG_POP
1308 Are preferred to AC_LANG_SAVE, AC_LANG_RESTORE.
1311 - AC_FUNC_CHOWN, AC_FUNC_MALLOC, AC_FUNC_STRERROR_R,
1312 AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK, AC_FUNC_STAT, AC_FUNC_LSTAT,
1313 AC_FUNC_ERROR_AT_LINE, AC_FUNC_OBSTACK, AC_FUNC_STRTOD, AC_FUNC_FSEEKO.
1317 Sets GETGROUPS_LIBS.
1319 - AC_FUNC_GETLOADAVG
1320 Defines `HAVE_STRUCT_NLIST_N_UN_N_NAME' instead of `NLIST_NAME_UNION'.
1323 Now integrates `AC_DECL_YYTEXT' which is obsoleted.
1326 Arrange for large-file support.
1328 - AC_EXEEXT, AC_OBJEXT
1329 You are no longer expected to use them: their computation is
1330 performed by default.
1332 ** C++ compatibility
1333 Every macro has been revisited in order to support at best CC=c++.
1335 Major changes in Autoconf 2.14:
1336 There was no release of GNU Autoconf 2.14.
1338 Major changes in Autoconf 2.13:
1340 Released 1999-05-01 by Ben Elliston.
1342 * Support for building on Win32 systems where the only available C or
1343 C++ compiler is the Microsoft Visual C++ command line compiler
1344 (`cl'). Additional support for building on Win32 systems which are
1345 using the Cygwin or Mingw32 environments.
1346 * Support for alternative object file and executable file extensions.
1347 On Win32, for example, these are .obj and .exe. These are discovered
1348 using AC_OBJEXT and AC_EXEEXT, which substitute @OBJEXT@ and
1349 @EXEEXT@ in the output, respectively.
1350 * New macros: AC_CACHE_LOAD, AC_CACHE_SAVE, AC_FUNC_SELECT_ARGTYPES,
1351 AC_VALIDATE_CACHED_SYSTEM_TUPLE, AC_SEARCH_LIBS, AC_TRY_LINK_FUNC,
1352 AC_C_STRINGIZE, AC_CHECK_FILE(S), AC_PROG_F77 (and friends).
1353 * AC_DEFINE now has an optional third argument for a description to be
1354 placed in the config header input file (e.g. config.h.in).
1355 * The C++ code fragment compiled for the C++ compiler test had to be
1356 improved to include an explicit return type for main(). This was
1357 causing failures on systems using recent versions of the EGCS C++
1359 * Fixed an important bug in AC_CHECK_TYPE that would cause a configure
1360 script to report that `sometype_t' was present when only `type_t'
1362 * Merge of the FSF version of config.guess and config.sub to modernize
1363 these scripts. Add support for a few new hosts in config.guess.
1364 Incorporate latest versions of install-sh, mkinstalldirs and
1365 texinfo.tex from the FSF.
1366 * autoreconf is capable of running automake if necessary (and
1368 * Support for Fortran 77. See the Texinfo documentation for details.
1369 * Bug fixes and workarounds for quirky bugs in vendor utilities.
1371 Major changes in Autoconf 2.12:
1373 Released 1996-11-26 by David J. MacKenzie
1375 * AC_OUTPUT and AC_CONFIG_HEADER can create output files by
1376 concatenating multiple input files separated by colons, like so:
1377 AC_CONFIG_HEADER(config.h:conf.pre:config.h.in:conf.post)
1378 AC_OUTPUT(Makefile:Makefile.in:Makefile.rules)
1379 The arguments may be shell variables, to compute the lists on the fly.
1380 * AC_LINK_FILES and AC_CONFIG_SUBDIRS may be called multiple times.
1381 * New macro AC_OUTPUT_COMMANDS adds more commands to run in config.status.
1384 Major changes in Autoconf 2.11:
1386 Released November 18th, 1996, by David J. MacKenzie
1388 * AC_PROG_CC and AC_PROG_CXX check whether the compiler works.
1389 They also default CFLAGS/CXXFLAGS to "-g -O2" for gcc, instead of "-g -O".
1390 * AC_REPLACE_FUNCS defines HAVE_foo if the system has the function `foo'.
1391 * AC_CONFIG_HEADER expands shell variables in its argument.
1392 * New macros: AC_FUNC_FNMATCH, AC_FUNC_SETPGRP.
1393 * The "checking..." messages and the source code for test programs that
1394 fail are saved in config.log.
1395 * Another workaround has been added for seds with small command length limits.
1396 * config.sub and config.guess recognize more system types.
1399 Major changes in Autoconf 2.10:
1401 Released May 7th, 1996, by Roland McGrath
1404 * The cache variable names used by `AC_CHECK_LIB(LIB, FUNC, ...)' has
1405 changed: now $ac_cv_lib_LIB_FUNC, previously $ac_cv_lib_LIB.
1407 Major changes in Autoconf 2.9:
1409 Released March 16th, 1996, by Roland McGrath
1413 Major changes in Autoconf 2.8:
1415 Released March 8th, 1996, by Roland McGrath
1419 Major changes in Autoconf 2.7:
1421 Released November 22nd, 1995, by David J. MacKenzie
1425 Major changes in Autoconf 2.6:
1427 Released November 20th, 1995, by David J. MacKenzie
1431 Major changes in Autoconf 2.5:
1433 Released November 17th, 1995, by Roland McGrath
1435 * New configure options --bindir, --libdir, --datadir, etc., with
1436 corresponding output variables.
1437 * New macro: AC_CACHE_CHECK, to make using the cache easier.
1438 * config.log contains the command being run as well as any output from it.
1439 * AC_CHECK_LIB can check for libraries with "." or "/" or "+" in their name.
1440 * AC_PROG_INSTALL doesn't cache a name for install-sh, for sharing caches.
1441 * AC_CHECK_PROG, AC_PATH_PROG, AC_CHECK_PROGS, AC_PATH_PROGS, and
1442 AC_CHECK_TOOL can search a path other than $PATH.
1443 * AC_CHECK_SIZEOF takes an optional size to use when cross-compiling.
1445 Major changes in Autoconf 2.4:
1447 Released June 14th, 1995, by David J. MacKenzie
1449 * Fix a few bugs found by Emacs testers.
1451 Major changes in Autoconf 2.3:
1453 Released March 27th, 1995, by David J. MacKenzie
1455 * Fix the cleanup trap in several ways.
1456 * Handle C compilers that are picky about option placement.
1457 * ifnames gets the version number from the right directory.
1459 Major changes in Autoconf 2.2:
1461 Released March 8th, 1995, by David J. MacKenzie
1463 * The ifnames utility is much faster but requires a "new awk" interpreter.
1464 * AC_CHECK_LIB and AC_HAVE_LIBRARY check and add the new
1465 library before existing libs, not after, in case it uses them.
1466 * New macros: AC_FUNC_GETPGRP, AC_CHECK_TOOL.
1467 * Lots of bug fixes.
1468 * Many additions to the TODO file :-)
1470 Major changes in Autoconf 2.1:
1472 Released November 4th, 1994, by David J. MacKenzie
1475 * More explanations in the manual.
1476 * Fix a spurious failure in the testsuite.
1477 * Clarify some warning messages.
1478 * autoreconf by default only rebuilds configure and config.h.in files
1479 that are older than any of their particular input files; there is a
1480 --force option to use after installing a new version of Autoconf.
1482 Thanks to everybody who's submitted changes and additions to Autoconf!
1483 I've incorporated many of them, and am still considering others for
1484 future releases -- but I didn't want to postpone this release indefinitely.
1486 Caution: don't indiscriminately rebuild configure scripts with
1487 Autoconf version 2. Some configure.in files need minor adjustments to
1488 work with it; the documentation has a chapter on upgrading. A few
1489 configure.in files, including those for GNU Emacs and the GNU C
1490 Library, need major changes because they relied on undocumented
1491 internals of version 1. Future releases of those packages will have
1492 updated configure.in files.
1494 It's best to use GNU M4 1.3 (or later) with Autoconf version 2.
1495 Autoconf now makes heavy use of M4 diversions, which were implemented
1496 inefficiently in GNU M4 releases before 1.3.
1498 Major changes in Autoconf 2.0:
1500 Released October 26th, 1994, by David J. MacKenzie
1502 ** New copyright terms:
1503 * There are no restrictions on distribution or use of configure scripts.
1506 * Autoconf manual is reorganized to make information easier to find
1507 and has several new indexes.
1508 * INSTALL is reorganized and clearer and is now made from Texinfo source.
1511 * autoscan to generate a preliminary configure.in for a package by
1512 scanning its source code for commonly used nonportable functions,
1513 programs, and header files.
1514 * ifnames to list the symbols used in #if and #ifdef directives in a
1516 * autoupdate to update a configure.in to use the version 2 macro names.
1517 * autoreconf to recursively remake configure and configuration header
1518 files in a source tree.
1520 ** Changed utilities:
1521 * autoheader can take pieces of acconfig.h to replace config.h.{top,bot}.
1522 * autoconf and autoheader can look for package-local definition files
1523 in an alternate directory.
1526 * AC_CACHE_VAL to share results of tests between configure runs.
1527 * AC_DEFUN to define macros, automatically AC_PROVIDE them, and ensure
1528 that macros invoked with AC_REQUIRE don't interrupt other macros.
1529 * AC_CONFIG_AUX_DIR, AC_CANONICAL_SYSTEM, AC_CANONICAL_HOST, AC_LINK_FILES to
1530 support deciding unguessable features based on the host and target types.
1531 * AC_CONFIG_SUBDIRS to recursively configure a source tree.
1532 * AC_ARG_PROGRAM to use the options --program-prefix,
1533 --program-suffix, and --program-transform-name to change the names
1534 of programs being installed.
1535 * AC_PREFIX_DEFAULT to change the default installation prefix.
1536 * AC_TRY_COMPILE to compile a test program without linking it.
1537 * AC_CHECK_TYPE to check whether sys/types.h or stdlib.h defines a given type.
1538 * AC_CHECK_LIB to check for a particular function and library.
1539 * AC_MSG_CHECKING and AC_MSG_RESULT to print test results, on a single line,
1540 whether or not the test succeeds. They obsolete AC_CHECKING and AC_VERBOSE.
1541 * AC_SUBST_FILE to insert one file into another.
1542 * AC_FUNC_MEMCMP to check whether memcmp is 8-bit clean.
1543 * AC_FUNC_STRFTIME to find strftime even if it's in -lintl.
1544 * AC_FUNC_GETMNTENT to find getmntent even if it's in -lsun or -lseq.
1545 * AC_HEADER_SYS_WAIT to check whether sys/wait.h is POSIX.1 compatible.
1548 * Many macros renamed systematically, but old names are accepted for
1549 backward compatibility.
1550 * AC_OUTPUT adds the "automatically generated" comment to
1551 non-Makefiles where it finds @configure_input@ in an input file, to
1552 support files with various comment syntaxes.
1553 * AC_OUTPUT does not replace "prefix" and "exec_prefix" in generated
1554 files when they are not enclosed in @ signs.
1555 * AC_OUTPUT allows the optional environment variable CONFIG_STATUS to
1556 override the file name "config.status".
1557 * AC_OUTPUT takes an optional argument for passing variables from
1558 configure to config.status.
1559 * AC_OUTPUT and AC_CONFIG_HEADER allow you to override the input-file names.
1560 * AC_OUTPUT automatically substitutes the values of CFLAGS, CXXFLAGS,
1561 CPPFLAGS, and LDFLAGS from the environment.
1562 * AC_PROG_CC and AC_PROG_CXX now set CFLAGS and CXXFLAGS, respectively.
1563 * AC_PROG_INSTALL looks for install-sh or install.sh in the directory
1564 specified by AC_CONFIG_AUXDIR, or srcdir or srcdir/.. or
1565 srcdir/../.. by default.
1566 * AC_DEFINE, AC_DEFINE_UNQUOTED, and AC_SUBST are more robust and smaller.
1567 * AC_DEFINE no longer prints anything, because of the new result reporting
1568 mechanism (AC_MSG_CHECKING and AC_MSG_RESULT).
1569 * AC_VERBOSE pays attention to --quiet/--silent, not --verbose.
1570 * AC_ARG_ENABLE and AC_ARG_WITH support whitespace in the arguments to
1571 --enable- and --with- options.
1572 * AC_CHECK_FUNCS and AC_CHECK_HEADERS take optional shell commands to
1573 execute on success or failure.
1574 * Checking for C functions in C++ works.
1577 * AC_REMOTE_TAPE and AC_RSH removed; too specific to tar and cpio, and
1578 better maintained with them.
1579 * AC_ARG_ARRAY removed because no one was likely using it.
1580 * AC_HAVE_POUNDBANG replaced with AC_SYS_INTERPRETER, which doesn't
1581 take arguments, for consistency with all of the other specific checks.
1584 * Comes with config.sub and config.guess, and uses them optionally.
1585 * Uses config.cache to cache test results. An alternate cache file
1586 can be selected with the --cache-file=FILE option.
1587 * Uses optional shell scripts $prefix/share/config.site and
1588 $prefix/etc/config.site to perform site or system specific initializations.
1589 * configure saves compiler output to ./config.log for debugging.
1590 * New files autoconf.m4 and autoheader.m4 load the other Autoconf macros.
1591 * acsite.m4 is the new name for the system-wide aclocal.m4.
1592 * Has a DejaGnu test suite.
1594 Major changes in Autoconf 1.11:
1596 * AC_PROG_INSTALL calls install.sh with the -c option.
1597 * AC_SET_MAKE cleans up after itself.
1598 * AC_OUTPUT sets prefix and exec_prefix if they weren't set already.
1599 * AC_OUTPUT prevents shells from looking in PATH for config.status.
1601 Plus a few other bug fixes.
1603 Major changes in Autoconf 1.10:
1605 * autoheader uses config.h.bot if present, analogous to config.h.top.
1606 * AC_PROG_INSTALL looks for install.sh in srcdir or srcdir/.. and
1608 * AC_PROG_CXX looks for cxx as a C++ compiler.
1610 Plus several bugs fixed.
1612 Major changes in Autoconf 1.9:
1614 * AC_YYTEXT_POINTER replaces AC_DECLARE_YYTEXT.
1615 * AC_SIZEOF_TYPE generates the cpp symbol name automatically,
1616 and autoheader generates entries for those names automatically.
1617 * AC_FIND_X gets the result from xmkmf correctly.
1618 * AC_FIND_X assumes no X if --without-x was given.
1619 * AC_FIND_XTRA adds libraries to the variable X_EXTRA_LIBS.
1620 * AC_PROG_INSTALL finds OSF/1 installbsd.
1622 Major changes in Autoconf 1.8:
1625 * New macros AC_LANG_C, AC_LANG_CPLUSPLUS, AC_LANG_SAVE, AC_LANG_RESTORE,
1626 AC_PROG_CXX, AC_PROG_CXXCPP, AC_REQUIRE_CPP
1627 for checking both C++ and C features in one configure script.
1628 * New macros AC_CHECKING, AC_VERBOSE, AC_WARN, AC_ERROR for printing messages.
1629 * New macros AC_FIND_XTRA, AC_MMAP, AC_SIZEOF_TYPE, AC_PREREQ,
1630 AC_SET_MAKE, AC_ENABLE.
1633 * AC_FIND_X looks for X in more places.
1634 * AC_PROG_INSTALL defaults to install.sh instead of cp, if it's in srcdir.
1635 install.sh is distributed with Autoconf.
1636 * AC_DECLARE_YYTEXT has been removed because it can't work, pending
1637 a rewrite of quoting in AC_DEFINE.
1638 * AC_OUTPUT adds its comments in C format when substituting in C files.
1639 * AC_COMPILE_CHECK protects its ECHO-TEXT argument with double quotes.
1641 ** New or changed command line options:
1642 * configure accepts --enable-FEATURE[=ARG] and --disable-FEATURE options.
1643 * configure accepts --without-PACKAGE, which sets withval=no.
1644 * configure accepts --x-includes=DIR and --x-libraries=DIR.
1645 * Giving --with-PACKAGE no argument sets withval=yes instead of withval=1.
1646 * configure accepts --help, --version, --silent/--quiet, --no-create options.
1647 * configure accepts and ignores most other Cygnus configure options, and
1648 warns about unknown options.
1649 * config.status accepts --help, --version options.
1651 ** File names and other changes:
1652 * Relative srcdir values are not made absolute.
1653 * The values of @prefix@ and @exec_prefix@ and @top_srcdir@ get substituted.
1654 * Autoconf library files are installed in ${datadir}/autoconf, not ${datadir}.
1655 * autoheader optionally copies config.h.top to the beginning of config.h.in.
1656 * The example Makefile dependencies for configure et al. work better.
1657 * Namespace cleanup: all shell variables used internally by Autoconf
1658 have names beginning with `ac_'.
1660 More big improvements are in process for future releases, but have not
1661 yet been (variously) finished, integrated, tested, or documented enough
1664 Major changes in Autoconf 1.7:
1666 * New macro AC_OBSOLETE.
1667 * Bugs in Makefile.in fixed.
1668 * AC_LONG_FILE_NAMES improved.
1670 Major changes in Autoconf 1.6:
1672 * New macro AC_LONG_64_BITS.
1673 * Multiple .h files can be created.
1674 * AC_FIND_X looks for X files directly if it doesn't find xmkmf.
1675 * AC_ALLOCA defines C_ALLOCA if using alloca.c.
1676 * --with-NAME can take a value, e.g., --with-targets=sun4,hp300bsd.
1677 * Unused --no-create option to configure removed.
1678 * autoheader doesn't change the timestamp of its output file if
1679 the file didn't change.
1680 * All macros that look for libraries now use AC_HAVE_LIBRARY.
1681 * config.status checks three optional environment variables to
1682 modify its behavior.
1683 * The usual bug fixes.
1685 Major changes in Autoconf 1.5:
1687 * New macros AC_FIND_X, AC_OFF_T, AC_STAT_MACROS_BROKEN, AC_REVISION.
1688 * autoconf and autoheader scripts have GNU standards conforming
1689 --version and --help options (they print their message and exit).
1692 Major changes in Autoconf 1.4:
1694 * New macros AC_HAVE_POUNDBANG, AC_TIME_WITH_SYS_TIME, AC_LONG_DOUBLE,
1695 AC_GETGROUPS_T, AC_DEFINE_UNQUOTED.
1696 * autoconf and autoheader use the M4 environment variable to determine the
1697 name of the M4 program to use.
1698 * The --macrodir option to autoconf and autoheader specifies the directory
1699 in which acspecific.m4, acgeneral.m4, etc. reside if not the default.
1700 * autoconf and autoheader can take `-' as their file names, which means to
1701 read stdin as input.
1702 * Resulting configure scripts can take a --verbose option which causes them
1703 to print the results of their tests.
1704 * AC_DEFINE quotes its second argument in such a way that spaces, magic
1705 shell characters, etc. will be preserved during various stages of
1706 expansion done by the shell. If you don't want this, use
1707 AC_DEFINE_UNQUOTED instead.
1708 * Much textual processing done with external calls to tr and sed have been
1709 internalized with builtin M4 `patsubst' and `translit' calls.
1710 * AC_OUTPUT doesn't hardwire the file names it outputs. Instead, you can
1711 set the shell variables `gen_files' and `gen_config' to the list of
1712 file names to output.
1713 * AC_DECLARE_YYTEXT does an AC_SUBST of `LEX_OUTPUT_ROOT', which may be
1714 "lex.yy" or "lexyy", depending on the system.
1715 * AC_PROGRAMS_CHECK takes an optional third arg. If given, it is used as
1717 * If AC_ALLOCA chooses alloca.c, it also defines STACK_DIRECTION.
1718 * AC_CONST works much more reliably on more systems.
1721 Major changes in Autoconf 1.3:
1723 configure no longer requires awk for packages that use a config.h.
1724 Support handling --with-PACKAGE options.
1725 New `autoheader' script to create `config.h.in' from `configure.in'.
1726 Ignore troublesome -lucb and -lPW when searching for alloca.
1727 Rename --exec_prefix to --exec-prefix for GNU standards conformance.
1728 Improve detection of STDC library.
1729 Add AC_HAVE_LIBRARY to check for non-default libraries.
1730 Function checking should work with future GNU libc releases.
1732 Major changes in Autoconf 1.2:
1734 The --srcdir option is now usually unnecessary.
1735 Add a file containing sample comments describing CPP macros.
1736 A comment in config.status tells which host it was configured on.
1737 Substituted variable values can now contain commas.
1738 Fix bugs in various feature checks.
1740 Major changes in Autoconf 1.1:
1742 Added AC_STRCOLL macro.
1743 Made AC_GETLOADAVG check for more things.
1744 AC_OUTPUT argument is now optional.
1749 Copyright (C) 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002,
1750 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
1752 This program is free software: you can redistribute it and/or modify
1753 it under the terms of the GNU General Public License as published by
1754 the Free Software Foundation, either version 3 of the License, or
1755 (at your option) any later version.
1757 This program is distributed in the hope that it will be useful,
1758 but WITHOUT ANY WARRANTY; without even the implied warranty of
1759 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1760 GNU General Public License for more details.
1762 You should have received a copy of the GNU General Public License
1763 along with this program. If not, see <http://www.gnu.org/licenses/>.