1 GNU Autoconf NEWS - User visible changes.
3 * Major changes in Autoconf 2.62a (2008-??-??)
5 ** AC_PATH_X now includes /lib64 and /usr/lib64 in its list of default
8 ** Newly obsolete macros
9 The following macro has been marked obsolete, since current porting
10 targets can safely assume C89 semantics that signal handlers return
11 void. We have no current plans to remove the macro.
15 ** Clients of m4_expand, such as AS_HELP_STRING and AT_SETUP, can now
16 handle properly quoted but otherwise unbalanced parentheses (for
17 some macros, this fixes a regression in 2.62).
19 ** Two new quadrigraphs have been introduced: @{:@ for (, and @:}@ for ),
20 allowing the output of unbalanced parantheses in more contexts.
22 ** The following m4sugar macros are new:
25 ** The following m4sugar macros now accept multiple arguments, as is the
26 case with underlying m4:
27 m4_defn m4_popdef m4_undefine
29 ** The following m4sugar macros now guarantee linear scaling; they
30 previously had linear scaling with m4 1.6 but quadratic scaling
31 when using m4 1.4.x. All macros built on top of these also gain
32 the scaling improvements.
33 m4_case m4_do m4_dquote_elt m4_foreach m4_join m4_list_cmp
34 m4_map m4_map_sep m4_max m4_min m4_shiftn
36 ** AT_KEYWORDS once again performs expansion on its argument, such that
37 AT_KEYWORDS([m4_if([$1], [], [default])]) no longer complains about
38 the possibly unexpanded m4_if [regression introduced in 2.62].
40 ** Config header templates `#undef UNDEFINED /* comment */' do not lead to
41 nested comments any more; regression introduced in 2.62.
44 * Major changes in Autoconf 2.62 (2008-04-05) [stable]
45 Released by Eric Blake, based on git versions 2.61a.*.
47 ** Many optimizations have been applied to make overall execution faster.
49 ** Autotest now makes use of shell functions.
51 ** config.status now uses awk instead of sed also for config headers.
53 - As a side effect, AC_DEFINE and AC_DEFINE_UNQUOTED now handle multi-line
54 values, i.e., backslash-newline combinations are handled correctly.
55 Further, for config headers, the total size of values is not limited by
56 the POSIX length limit of text lines any more, only each single line.
58 ** New config variable `top_build_prefix'.
60 ** New Autoconf macros:
61 AC_AUTOCONF_VERSION AC_OPENMP AC_PATH_PROGS_FEATURE_CHECK
63 ** AC_C_BIGENDIAN now supports universal binaries a la Mac OS X.
65 ** AC_C_RESTRICT now prefers to #define 'restrict' to a variant spelling
66 like '__restrict' if the variant spelling is available, as this is
67 more likely to work when mixing C and C++ code.
69 ** AC_CHECK_ALIGNOF's type argument T is now documented better: it must
70 be a string of tokens such that "T y;" is a valid member declaration
73 ** AC_CHECK_SIZEOF now accepts objects as well as types: the general rule
74 is that sizeof (X) works, then AC_CHECK_SIZEOF (X) should work.
76 ** AC_CHECK_TYPE and AC_CHECK_TYPES now work on any C type-name; formerly,
77 they did not work for function types. In C++, they now work on any
78 type-id that can be the operand of sizeof; this is similar to C,
79 except it excludes anonymous struct and union types. Formerly,
80 some (but not all) C++ types involving anonymous struct and union
81 were accepted, though this was not documented.
83 ** AC_CONFIG_LINKS now prefers to link against files in the build tree
84 if found, and it works to link against a file of the same name in
85 the source tree, even if both trees coincide.
87 ** AC_INIT no longer alters $@; regression introduced in 2.60.
89 ** AC_USE_SYSTEM_EXTENSIONS now defines _ALL_SOURCE for Interix platforms.
91 ** AS_HELP_STRING no longer underquotes its first argument; it also handles
92 the case where the first argument contains single-quoted commas.
93 For example, "AS_HELP_STRING([-a, [--arg[=foo]]], [bar])" produces:
94 " -a, --arg[=foo] bar"
95 Additionally, the macro now takes two additional arguments,
96 indent-column and wrap-column; these should not normally be needed,
97 but can be used to fine-tune how the output text is wrapped.
99 ** AC_PROG_INSTALL now requires an install program that can install multiple
100 files into a target directory.
102 ** The command 'autoconf -' now correctly processes a file from stdin.
104 ** 'autoreconf -m' now honors $MAKE.
106 ** For all of the directory arguments for 'configure', such as '--prefix'
107 or '--bindir', trailing slashes are stripped. As an example, if
108 tab completion in the user's shell appends trailing slashes, the
109 command './configure --prefix=/usr/' will still result in an
110 expanded libdir value of /usr/lib, not /usr//lib.
112 ** `configure --help=recursive' now works in read-only trees and from
113 unconfigured build trees.
115 ** If precious variables differ only in whitespace, then the cache consistency
116 check warns instead of fails, and reuses the old value.
118 ** AT_BANNER is now documented.
120 ** AT_SETUP now handles macro expansions properly when calculating line
123 ** Autotest now determines $srcdir correctly.
125 ** Testsuites built by autotest now accept a -C/--directory=DIR option
126 to adjust the working directory prior to creating files.
128 ** Autoconf now requires GNU M4 1.4.5 or later. Earlier versions of M4 have
129 a bug in macro tracing that interferes with the interaction between
130 Autoconf and Automake. GNU M4 1.4.11 or later is recommended. The
131 configure search for a working M4 is improved.
133 ** For portability with the eventual M4 2.0, macros should no longer use
134 anything larger than $9 to refer to arguments.
136 ** Documentation for m4sugar is improved.
138 - The following macros were previously available as undocumented
139 interfaces; the macros are now documented as stable interfaces.
141 __oline__ m4_assert m4_bmatch m4_bpatsubsts m4_car m4_case
142 m4_cdr m4_default m4_divert_once m4_divert_pop m4_divert_push
143 m4_divert_text m4_do m4_errprintn m4_fatal m4_flatten
144 m4_ifndef m4_ifset m4_ifval m4_ifvaln m4_location
145 m4_n m4_shiftn m4_strip m4_warn
147 - The following macros were previously available as undocumented
148 interfaces, but had bug fixes or semantic changes as part of this
149 release. Packages that relied on the undocumented behavior
150 should be analyzed to make sure they will still work with the
151 new documented behavior.
153 m4_cmp m4_list_cmp m4_join m4_map m4_map_sep m4_sign
154 m4_text_box m4_text_wrap m4_version_compare
156 - The m4_wrap macro used to have unspecified order, but now
157 guarantees FIFO order. m4_wrap_lifo was added to guarantee LIFO
160 - Packages using the undocumented m4sugar macro m4_PACKAGE_VERSION
161 should consider using the new AC_AUTOCONF_VERSION instead.
163 - m4sugar macros that are not documented in the manual are still
164 deemed experimental, and should not be used outside of Autoconf.
166 ** The m4sugar macros m4_append and m4_append_uniq, first documented in
167 2.60, have been fixed to treat both the string and the separator
168 arguments consistently with regards to quoting. Prior to this fix,
169 m4_append_uniq could mistakenly duplicate entries if the expansion
170 of the separator resulted in a different string (for example, if it
171 contained quotes, a comma, or a macro name). However, it means
172 that programs previously using
173 m4_append([name], [string], [[, ]])
174 are now using a four-character separator instead of the intended
175 comma and space. If you need portability to earlier versions of
176 Autoconf, you can insert the following snippet after AC_INIT but
177 before any other macro expansions, to enforce the new semantics:
178 m4_pushdef([m4_append], [m4_define([$1],
179 m4_ifdef([$1], [m4_defn([$1])[$3]])[$2])])
180 Additionally, m4_append_uniq now takes optional parameters that can
181 be used to take action depending on whether anything was appended,
182 and warns if a non-empty separator occurs within the string being
183 appended, since that can lead to duplicates.
185 ** The following m4sugar macros are new:
186 m4_append_uniq_w m4_apply m4_combine m4_cond m4_count
187 m4_dquote_elt m4_echo m4_expand m4_ignore m4_make_list m4_max
188 m4_min m4_newline m4_shift2 m4_shift3 m4_unquote m4_wrap_lifo
190 ** Warnings are now generated by default when an installer invokes
191 'configure' with an unknown --enable-* or --with-* option.
192 These warnings can be disabled with the new AC_DISABLE_OPTION_CHECKING
193 macro, or by invoking 'configure' with --disable-option-checking.
195 ** Existing obsolete macros
196 The documentation for the following macros is adjusted to make it
197 more clear that they have previously been marked obsolete, as their
198 functionality can be accomplished by other macros. We have no
199 current plans to remove them from Autoconf.
201 AC_ENABLE AC_STRUCT_ST_BLKSIZE AC_STRUCT_ST_RDEV AC_WITH
203 ** Newly obsolete macros
204 The following macros have been marked obsolete, as they only
205 perform a subset of AC_USE_SYSTEM_EXTENSIONS. We have no current
206 plans to remove them.
208 AC_AIX AC_GNU_SOURCE AC_ISC_POSIX AC_MINIX
210 ** AC_C_LONG_DOUBLE is obsolescent.
211 The documentation now says that AC_C_LONG_DOUBLE is obsolescent: it
212 tests for problems that are so old that it is no longer of
213 practical importance on current systems. New programs need not use
214 AC_C_LONG_DOUBLE. We have no current plans to remove it.
216 ** AC_DIAGNOSE, AC_WARNING, and AC_FATAL are obsolescent.
217 The documentation now favors the use of M4sugar macros m4_warn and
218 m4_fatal, since the naming makes it more obvious that the
219 diagnostics are associated with M4 expansion (ie. when running
220 `autoconf'), and offers less confusion with the AC_MSG_ERROR,
221 AC_MSG_FAILURE, and AC_MSG_WARN macros which manage diagnostics
222 when running `configure'. We have no current plans to remove these
226 * Major changes in Autoconf 2.61a (2006-12-11)
228 ** AC_FUNC_FSEEKO was broken in 2.61; it didn't make fseeko and ftello visible
229 on many platforms. This has been fixed.
231 ** AC_FUNC_SETVBUF_REVERSED is now obsolete. It is still defined for backward
232 compatibility but it does nothing. The macro was already
233 obsolescent, as the last systems to have the problem were those
234 based on SVR2, which became obsolete in 1987. The macro had bugs
235 on some modern systems and could no longer be maintained reliably
236 due to lack of ancient systems to test it on.
238 ** config.status now uses awk instead of sed for most substitutions, for speed.
240 - As a side effect multi-line values of substituted variables no
241 longer have a small limit in total size, though for portability
242 each line should not exceed the POSIX length limit for text lines.
244 - It is now documented that Makefile.in should not contain
245 overlapping variable occurrences, e.g., @VAR1@VAR2@.
246 Autoconf's behavior was always iffy in such cases, and the
247 awk implementation has changed the behavior.
249 ** Many uses of 'echo' have been rewritten so that Autoconf-generated
250 scripts have fewer problems with strings or file names containing
251 embedded special characters such as backslash or leading "-". This
252 was implemented by using `printf '%s\n' "$foo"' instead of `echo
253 "$foo"' when printf works. Due to the implementation technique
254 used, Autoconf-generated scripts now run considerably more slowly
255 on ancient implementations lacking printf. However, this should
256 not be a problem, since Autoconf-generated scripts in practice
257 invariably find a more-modern shell these days.
260 * Major changes in Autoconf 2.61 (2006-11-17)
262 ** New macros AC_C_FLEXIBLE_ARRAY_MEMBER, AC_C_VARARRAYS.
264 ** AC_ARG_ENABLE and AC_ARG_WITH now allow '.' in feature and package names.
267 * Major changes in Autoconf 2.60b (2006-10-22)
270 Autoconf-generated shell scripts no longer export BIN_SH, due to
271 configuration hassles with this. Installers who need BIN_SH in
272 their environment should set it before invoking 'configure' and
273 'make'. As far as we know, this affects only Unixware installations.
275 ** Obsolescent macros
276 The documentation now says that the following macros are obsolescent,
277 as they are superseded by Gnulib:
279 AC_FUNC_FNMATCH AC_FUNC_FNMATCH_GNU AC_FUNC_GETLOADVG AC_REPLACE_FNMATCH
281 New programs should use the Gnulib counterparts of these macros.
282 We have no current plans to remove them from Autoconf.
284 ** AC_COMPUTE_INT no longer caches or reports results.
286 ** AC_CHECK_DECL now also works with aggregate objects.
288 ** AC_USE_SYSTEM_EXTENSIONS now defines _TANDEM_SOURCE for NonStop platforms.
290 ** GNU M4 1.4.7 or later is now recommended.
293 New M4sugar macro, which is more secure than the POSIX M4 maketemp.
296 Now an alias for m4_mkstemp.
298 * Major changes in Autoconf 2.60a (2006-08-25)
300 ** GNU M4 1.4.6 or later is now recommended.
302 ** The check for C99 now tests for varargs macros, as documented.
303 It also tests that the preprocessor supports 64-bit integers.
305 ** Autoconf now uses constructs like "#ifdef HAVE_STDLIB_H" rather than
306 "#if HAVE_STDLIB_H", so that it now works with "gcc -Wundef -Werror".
308 ** The functionality of the undocumented _AC_COMPUTE_INT is now provided
309 by a public and documented macro, AC_COMPUTE_INT. The parameters to the
310 two macros are different, so autoupdate will not change the old private name
311 to the new one. _AC_COMPUTE_INT may be removed in a future release.
313 ** AC_TYPE_LONG_LONG_INT and AC_TYPE_UNSIGNED_LONG_LONG_INT now require
314 that long long types be at least 64 bits wide, as C99 and tradition
315 requires. Formerly, they accepted implementations of any width.
318 * Major changes in Autoconf 2.60
320 Released 2006-06-23, by Ralf Wildenhues.
322 ** Autoconf no longer depends on whether m4wrap is FIFO (as Posix requires)
323 or LIFO (as in GNU M4 1.4.x). GNU M4 2.0 is expected to conform to Posix
324 here, so m4wrap/m4_wrap users should no longer depend on LIFO behavior.
326 ** Provide a way to turn off warnings about the changed directory variables.
328 * Major changes in Autoconf 2.59d
330 Released 2006-06-05, by Ralf Wildenhues.
332 ** GNU make now recommended for VPATH builds
333 INSTALL now suggests VPATH builds (e.g., "sh ../srcdir/configure")
334 only if you use GNU make. In practice, other 'make' implementations
335 have too many subtle incompatibilities in their support for VPATH.
336 Many packages (including Autoconf itself) are portable to other
337 'make' implementations, but some packages are not, and recommending
338 GNU make keeps the installation instructions simpler.
340 ** Even more safety checks for the new Directory variables:
341 Warn about suspicious `${datarootdir}' found in config files output.
343 ** AC_TRY_COMMAND, AC_TRY_EVAL, ac_config_guess, ac_config_sub, ac_configure
344 These never-documented macros and variables have been marked with
345 comments saying that they may be removed in a future release,
346 because their use can lead to unintended code being executed.
347 If you need functionality that only these macros or variables
348 currently supply, please write bug-autoconf@gnu.org.
350 ** AC_SUBST, AC_DEFINE
351 Literal arguments to these are passed to m4_pattern_allow now.
354 Passing 'ac_cv_prog_cc_stdc=no' to 'configure' now sets ac_cv_prog_cc_c99
355 and ac_cv_prog_cc_c89 to 'no' as well, for backward compatibility with
356 obsolete K&R tests in the Automake test suite.
365 Now more robust with special characters in file names, or when
366 multiple processes create the same directory at the same time.
368 ** Obsolescent macros
369 The documentation now says that the following macros are obsolescent:
370 they test for problems that are so old that they are no longer of
371 practical importance on current systems.
373 AC_C_BACKSLASH_A AC_FUNC_MEMCMP AC_HEADER_DIRENT
374 AC_C_CONST AC_FUNC_SELECT_ARGTYPES AC_HEADER_STAT
375 AC_C_PROTOTYPES AC_FUNC_SETPGRP AC_HEADER_STDC
376 AC_C_STRINGIZE AC_FUNC_SETVBUF_REVERSED AC_HEADER_SYS_WAIT
377 AC_C_VOLATILE AC_FUNC_STAT AC_HEADER_TIME
378 AC_FUNC_CLOSEDIR_VOID AC_FUNC_STRFTIME AC_ISC_POSIX
379 AC_FUNC_GETPGRP AC_FUNC_UTIME_NULL AC_PROG_GCC_TRADITIONAL
380 AC_FUNC_LSTAT AC_FUNC_VPRINTF AC_STRUCT_TM
382 New programs need not use these macros. We have no current plans to
386 For compatibility with future Libtool 2.0, autoreconf will invoke
387 libtoolize with the option `--ltdl' now, if LT_CONFIG_LTDL_DIR is
390 * Major changes in Autoconf 2.59c
392 Released 2006-04-12, by Ralf Wildenhues.
394 ** The configure command now redirects standard input from /dev/null,
395 to help avoid problems with subsidiary commands that might mistakenly
396 read standard input. AS_ORIGINAL_STDIN_FD points to the original
397 standard input before this redirection, if you really want configure to
398 read from standard input.
400 ** Directory variables adjusted to recent changes in the GNU Coding Standards.
401 The following directory variables are new:
403 datarootdir read-only architecture-independent data root [PREFIX/share]
404 localedir locale-specific message catalogs [DATAROOTDIR/locale]
405 docdir documentation root [DATAROOTDIR/doc/PACKAGE]
406 htmldir html documentation [DOCDIR]
407 dvidir dvi documentation [DOCDIR]
408 pdfdir pdf documentation [DOCDIR]
409 psdir ps documentation [DOCDIR]
411 The following variables have new default values:
413 datadir read-only architecture-independent data [DATAROOTDIR]
414 infodir info documentation [DATAROOTDIR/info]
415 mandir man documentation [DATAROOTDIR/man]
417 This means that if you use any of `@datadir@', `@infodir@', or
418 `@mandir@' in a file, you will have to ensure `${datarootdir}' is
419 defined in this file. As a temporary measure, if any of those are
420 found but no mention of `datarootdir', the substitutions will be
421 replaced with values that do not contain `${datarootdir}', and a
422 warning will be issued.
424 ** @top_builddir@ is now a dir name: it is always nonempty and doesn't have
425 a trailing slash. Similar change will be made to ac_top_builddir in a
426 future release; the old style value, which matches (../)*, is (and will
427 continue to be) available as ac_top_build_prefix.
430 New macro to check for support of 'typeof' syntax a la GNU C.
432 ** AC_CHECK_DECLS_ONCE, AC_CHECK_FUNCS_ONCE, AC_CHECK_HEADERS_ONCE
433 New "once-only" variants of commonly-used macros, to make 'configure'
434 smaller and faster in common cases.
437 New macro to check for strtold with C99 semantics.
440 New macro that lets builder disable assertions at 'configure'-time.
443 Now checks for X11/Xlib.h and XrmInitialize (X proper) rather than
444 X11/Intrinsic.h and XtMalloc (Xt).
446 ** AC_PRESERVE_HELP_ORDER
447 New macro that causes `configure' to display help strings for AC_ARG_ENABLE
448 and AC_ARG_WITH arguments in one region, in the order defined. The default
449 behavior is to group options of each classes separately.
451 ** AC_PROG_CC, AC_PROG_CXX
452 No longer automatically arrange to declare the 'exit' function of C,
453 when a C++ compiler is used. Standard Autoconf macros no longer use
454 'exit', so this is no longer an issue for them. If you use C++, and
455 want to call 'exit', you'll have to arrange for its declaration
456 yourself. But we now suggest you return from 'main' instead.
458 ** AC_PROG_CC_C89, AC_PROG_CC_C99
459 New macros for ISO C99 support. AC_PROG_CC_C89 and AC_PROG_CC_C99
460 check for ANSI C89 and ISO C99 support respectively.
463 Has been unobsoleted, and will check if the compiler supports ISO
464 C99, falling back to ANSI C89 if not. ac_cv_prog_cc_stdc is
465 retained for backwards compatibility, assuming the value of
466 ac_cv_prog_cc_c99 or ac_cv_prog_cc_c89 (whichever is valid, in
469 ** AC_STRUCT_DIRENT_D_INO, AC_STRUCT_DIRENT_D_TYPE
470 New macros for checking commonly-used members of struct dirent.
473 The substituted value can now contain newlines.
476 The substitution now occurs only when @variable@ is on a line by itself,
477 optionally surrounded by spaces and tabs. The whole line is replaced.
479 ** AC_TYPE_LONG_DOUBLE, AC_TYPE_LONG_DOUBLE_WIDER
480 New macros to check for long double, and whether it is wider than double.
481 The old macro AC_C_TYPE_LONG_DOUBLE has been marked as obsolete;
482 applications should switch to the new macro.
484 ** AC_TYPE_INT8_T, AC_TYPE_INT16_T, AC_TYPE_INT32_T, AC_TYPE_INT64_T,
485 AC_TYPE_INTMAX_T, AC_TYPE_INTPTR_T, AC_TYPE_LONG_LONG_INT, AC_TYPE_SSIZE_T,
486 AC_TYPE_UINT8_T, AC_TYPE_UINT16_T, AC_TYPE_UINT32_T, AC_TYPE_UINT64_T,
487 AC_TYPE_UINTMAX_T, AC_TYPE_UINTPTR_T, AC_TYPE_UNSIGNED_LONG_LONG_INT
488 New macros to check for C99 and POSIX types.
490 ** AC_USE_SYSTEM_EXTENSIONS
491 New macro to enable extensions to Posix.
494 New macro which is defined to the name of the first declared config header
495 or undefined if no config headers have been declared yet.
498 The macro correctly handles quadrigraphs now.
500 ** AS_BOURNE_COMPATIBLE, AS_SHELL_SANITIZE, AS_CASE
501 These macros are new or published now.
504 New macro for copyright notices in testsuite files.
506 ** ALLOCA, LIBOBJS, LTLIBOBJS
507 Object names added to these variables are now prefixed with `${LIBOBJDIR}',
508 as in `${LIBOBJDIR}alloca.o'. LIBOBJDIR is meant to be defined from
509 `Makefile.in' in case the object files lie in a different directory.
510 The LIBOBJDIR feature is experimental.
513 Supports --no-recursive now.
515 ** New macros to support Erlang/OTP.
516 New macros for configuring paths to Erlang tools and libraries:
517 AC_ERLANG_PATH_ERLC, AC_ERLANG_NEED_ERLC, AC_ERLANG_PATH_ERL,
518 AC_ERLANG_NEED_ERL, AC_ERLANG_CHECK_LIB, AC_ERLANG_SUBST_ROOT_DIR,
519 AC_ERLANG_SUBST_LIB_DIR.
521 New macros for configuring installation of Erlang libraries:
522 AC_ERLANG_SUBST_INSTALL_LIB_DIR, AC_ERLANG_SUBST_INSTALL_LIB_SUBDIR.
524 ** The manual now mentions Gnulib more prominently.
526 ** New macros to support Objective C.
527 AC_PROG_OBJC, AC_PROG_OBJCPP.
529 * Major changes in Autoconf 2.59b
531 Released 2004-08-20, by Paul Eggert.
534 New macro that computes the default alignment of a type.
536 ** AC_CHECK_TOOL, AC_PATH_TOOL, AC_CHECK_TOOLS
537 When cross-compiling, these macros will give a warning if the tool
538 is not prefixed. In the future, unprefixed cross tools will not
539 be detected; please consult the info documentation for information
540 about the reason of this change.
542 ** AC_CHECK_TARGET_TOOL, AC_PATH_TARGET_TOOL, AC_CHECK_TARGET_TOOLS
543 New macros that detect programs whose name is prefixed with the
544 target type, if the build type and target type are different.
546 ** AC_REQUIRE_AUX_FILE
547 New trace macro that declares expected auxiliary files.
550 New macro that tests for a grep program that accepts as a long a line
553 ** AC_PROG_EGREP, AC_PROG_FGREP
554 These macros now require AC_PROG_GREP, and try EGREP="$GREP -E" and
555 FGREP="$GREP -F" respectively if possible, or else run a path search for
556 a program that accepts as long a line as possible.
559 New macro that tests for a sed program that truncates as few characters
562 * Major changes in Autoconf 2.59
564 Released 2003-11-04, by Akim Demaille
566 ** ac_abs_builddir etc.
567 Absolute file names were actually relative in 2.58.
569 * Major changes in Autoconf 2.58
571 Released 2003-11-04, by Akim Demaille
574 core.* files are no longer removed, as they may be valid user files.
576 ** autoreconf and auxiliary directory
577 Autoreconf creates the auxiliary directory if needed. This is
578 especially useful for initial "bootstrapping" of fresh CVS checkouts.
580 ** AC_CONFIG_MACRO_DIR
581 Use this macro to declare the directory for local M4 macros for aclocal.
584 No longer includes twice the same file in LIBOBJS if invoked
587 ** AC_CONFIG_COMMANDS
588 The directory for its first argument is automatically created. For
591 AC_CONFIG_COMMANDS([src/modules.hh], [...])
593 $top_builddir/src/ is created if needed.
595 ** Autotest and local.at
596 The optional file local.at is always included in Autotest test suites.
599 The warnings are always issued, including with cached runs.
600 This became a significant problem since aclocal and automake can
601 run autoconf behind the scene.
603 ** autoheader warnings
604 The warnings of autoheader can be turned off, using --warning.
605 For instance, -Wno-obsolete disables the complaints about acconfig.h
606 and other deprecated constructs.
609 AC_C_RESTRICT, AC_INCLUDES_DEFAULT, AC_LANG_ASSERT, AC_LANG_WERROR,
612 ** AC_DECL_SYS_SIGLIST
616 Now checks that mktime is the inverse of localtime.
618 ** Improve DJGPP portability
619 The Autoconf tools and configure behave better under DJGPP.
621 ** Present But Cannot Be Compiled
622 New FAQ section dedicated to the mystic
624 configure: WARNING: pi.h: present but cannot be compiled
625 configure: WARNING: pi.h: check for missing prerequisite headers?
626 configure: WARNING: pi.h: proceeding with the preprocessor's result
629 ** Concurrent executions of autom4te
630 autom4te now locks its internal files, which enables concurrent
631 executions of autom4te, likely to happen if automake, autoconf,
632 autoheader etc. are run simultaneously.
635 Use of Libtool 1.5 and higher is encouraged. Compatibility with
636 Libtool pre-1.4 is not checked.
639 Testsuites no longer rerun failed tests in verbose mode; instead,
640 failures are logged while the test is run.
642 In addition, expected failures can be marked as such.
644 * Major changes in Autoconf 2.57
646 Released 2002-12-03 by Paul Eggert.
648 Bug fixes for problems with AIX linker, with freestanding C compilers,
649 with GNU M4 limitations, and with obsolete copies of GNU documents.
651 The Free Documentation License has been upgraded from 1.1 to 1.2.
653 * Major changes in Autoconf 2.56
655 Released 2002-11-15 by Akim Demaille.
657 One packaging problem fixed (config/install-sh was not executable).
659 * Major changes in Autoconf 2.55
661 Released 2002-11-14 by Akim Demaille.
665 Have your configure.ac checked by autoscan ("autoscan").
666 Try the warning options ("autoreconf -fv -Wall").
670 - AC_CHECK_HEADER, AC_CHECK_HEADERS
671 More information on proper use.
673 - Writing Test Programs
675 This sections explains how to write good test sources to use with
676 AC_COMPILE_IFELSE etc. It documents AC_LANG_PROGRAM and so forth.
678 - AC_FOO_IFELSE vs. AC_TRY_FOO
680 Explains why Autoconf moves from AC_TRY_COMPILE etc. to
681 AC_COMPILE_IFELSE and AC_LANG_PROGRAM etc.
685 - Is more robust to different Gettext installations.
687 - Produces messages (when --verbose) to be understood by Emacs'
690 - Supports -W/--warnings.
693 Once the GNU Build System reinstalled, run `./config.status
694 --recheck && ./config.status && make' if possible.
698 - Supports --cache, and --no-cache.
700 - ~/.autom4te.cfg makes it possible to disable the caching mechanism
701 (autom4te.cache). See `Customizing autom4te' in the documentation.
708 Support for the obsoleted options -m, --macrodir, -l, --localdir is
709 dropped in favor of the safer --include/--prepend-include scheme.
714 AC_COMPILER_IFELSE, AC_FUNC_MBRTOWC, AC_HEADER_STDBOOL,
715 AC_LANG_CONFTEST, AC_LANG_SOURCE, AC_LANG_PROGRAM, AC_LANG_CALL,
716 AC_LANG_FUNC_TRY_LINK, AC_MSG_FAILURE, AC_PREPROC_IFELSE.
719 Obsoleted macros are kept for Autoconf backward compatibility, but
720 should be avoided in configure.ac. Running autoupdate is advised.
723 - AC_DEFINE/AC_DEFINE_UNQUOTED
725 We have to stop using the old compatibility scheme --that tried to
726 avoid useless backslashes-- because Libtool 1.4.3 contains a
728 AC_DEFINE([error_t], [int],
729 [Define to a type to use for \`error_t' if it is not
730 otherwise available.])
732 We have to quote the single quotes and backslashes with \. The old
733 compatibility scheme saw that ` was backslashed, and therefore did
734 not quote the single quote... Failure. Hence, Autoconf 2.54 is not
735 compatible with Libtool. Autoconf 2.55 is, but in some cases might
736 produce more \ than wanted.
738 Please, note that in the future the same problem will happen with
739 AC_MSG_*: use `autoreconf -f -Wall'.
743 - Portability of the Autoconf package to Solaris.
745 - Spurious warnings caused by config.status.
746 This bug is benign, but painful: on some systems (typically
747 FreeBSD), warnings such as:
749 config.status: creating Makefile
750 mv: Makefile: set owner/group (was: 1357/0): Operation not permitted
752 could be issued. This is fixed.
755 Simultaneous executions of config.status are possible again.
757 - Precious variables accumulation
759 config.status could stack several copies of the precious variables
763 ** Plans for later versions
767 The compatibility hooks with the old scheme will be completely
768 removed. Please, advice/use `--build', `--host', and `--target'
771 - AC_CHECK_HEADER, AC_CHECK_HEADERS
773 The tests will be stricter, please make sure your invocations are
778 Shell functions will gradually be introduced, probably starting with
779 Autotest. If you know machines which are in use that you suspect
780 *not* to support shell functions, please run the test suite of
781 Autoconf 2.55 on it, and report the results to
782 bug-autoconf@gnu.org.
786 Special characters in AC_MSG_* need not be quoted. Currently,
787 Autoconf has heuristics to decide when a string is escaped, or has
788 to be escaped. This scheme is fragile, and will be removed; the
789 only risk is uglified messages. Please, run `autoreconf -f -Wall'
790 to find occurrences that will be affected.
792 * Major changes in Autoconf 2.54
794 Released 2002-09-13 by Akim Demaille.
798 - autoreconf no longer changes the version of the gettext/po/intl
799 support files. It now adds the files the correspond to the
800 AM_GNU_GETTEXT_VERSION declared in configure.ac.
802 Warning: It now relies on the 'autopoint' program, which is part
803 of GNU gettext 0.11.4 and newer.
805 Please note that you need to have a GNU gettext version that
806 corresponds at least to the AM_GNU_GETTEXT_VERSION declared
807 in configure.ac. You can upgrade to newer GNU gettext versions,
808 though, without needing to change configure.ac.
810 - The -I DIR or --include=DIR option now appends DIR to the include path
811 instead of prepending; this is for consistency with other GNU tools.
812 The new -B DIR or --prepend-include=DIR option has the old behavior.
817 Now handles all the gory details about LIBOBJS and LTLIBOBJS.
818 Please, remove lines such as
820 # This is necessary so that .o files in LIBOBJS are also
821 # built via the ANSI2KNR-filtering rules.
822 LIBOBJS=`echo $LIBOBJS|sed 's/\.o /\$U.o /g;s/\.o$/\$U.o/'`
824 and read the `AC_LIBOBJ vs LIBOBJS' section. Do not define U in
825 your Makefiles either.
827 - AC_CONFIG_LINKS now makes copies if it can't make links.
829 - AC_FUNC_FNMATCH now tests only for POSIX compatibility, reverting to
830 Autoconf 2.13 behavior. The new macro AC_FUNC_FNMATCH_GNU also
831 tests for GNU extensions to fnmatch, and replaces fnmatch if needed.
833 - AC_FUNC_SETVBUF_REVERSED no longer fails when cross-compiling.
835 - AC_PROG_CC_STDC is integrated into AC_PROG_CC.
837 - AC_PROG_F77 default search no longer includes cf77 and cfg77.
841 AC_C_BACKSLASH_A, AC_CONFIG_LIBOBJ_DIR, AC_GNU_SOURCE,
842 AC_PROG_EGREP, AC_PROG_FGREP, AC_REPLACE_FNMATCH,
843 AC_FUNC_FNMATCH_GNU, AC_FUNC_REALLOC, AC_TYPE_MBSTATE_T.
846 looks for getloadavg.c in the CONFIG_LIBOBJ_DIR.
849 Now defines HAVE_MALLOC to 0 if `malloc' does not work, and asks
850 for an AC_LIBOBJ replacement.
854 - Spurious complaints from `m4_bmatch' about invalid regular
855 expressions are suppressed.
857 - Empty top_builddirs are properly handled.
859 - AC_CHECK_MEMBER works correctly when the member is an aggregate.
862 Now colon in the optional path arguments are properly handled.
864 ** Improved portability
866 - Both Autoconf the package, and the scripts it produces, should run
867 more reliably with Zsh. Bear in mind it is the default Bourne shell
870 - Autoconf and the scripts it produces no longer assume the existence of
871 the obsolescent commands egrep and fgrep.
875 - Limitations of Make
879 The GNATS base moved to
880 http://bugs.gnu.org/cgi-bin/gnatsweb.pl?database=autoconf
881 (It is no longer available, though.)
886 Now contains the list of ouput variables and files (AC_SUBST,
889 * Major changes in Autoconf 2.53
891 Released 2002-03-08 by Akim Demaille.
895 Perl 5.005_03 or later is required: autom4te is written in Perl and is
896 needed by autoconf. autoheader, autoreconf, ifnames, and autoscan are
902 Argument requirements, output variables, defined macros.
903 - M4sugar, M4sh, Autotest
905 - Double quoting macros
906 AC_TRY_CPP, AC_TRY_COMPILE, AC_TRY_LINK and AC_TRY_RUN.
908 The Autoconf manual is now distributed under the terms of the GNU FDL.
909 - Section `Hosts and Cross-Compilation'
910 Explains the rationale for the 2.5x changes in the cross-compilation
911 chain, and in the relationships between build, host, and target
913 Emphasizes that `cross-compilation' == `--host is given'.
914 If you are working on compilers etc., be sure to read this section.
915 - Section `AC_LIBOBJ vs. LIBOBJS'
916 Explains why assigning LIBOBJS directly is now an error.
917 Details how to update the code.
922 Now used instead of hard coded line numbers.
923 This eases the comparison of `configure's, and diminishes the
924 pressure over control version archives.
925 Automatic replacement for shells that don't support this feature.
926 - New output variables
927 @builddir@, @top_builddir@, @abs_srcdir@, @abs_top_srcdir@, @abs_builddir@,
932 Autoconf and Autotest modes are provided.
937 New, used by the Autoconf suite to cache and speed up most processing.
939 Supported by autom4te, autoconf and autoheader.
941 Replaces --autoconf-dir and --localdir in autoconf, autoheader,
942 autoupdate, and autoreconf.
944 No longer passes --cygnus, --foreign, --gnits, --gnu, --include-deps:
945 automake options are to be given via AUTOMAKE_OPTIONS.
947 Runs gettextize and libtoolize when appropriate.
949 --m4dir is no longer supported.
951 Now runs only in the specified directories, defaulting to `.',
952 but understands AC_CONFIG_SUBDIRS for dependent directories.
953 Before, it used to run on all the `configure.ac' found in the
955 Independent packages are properly updated.
959 - The top level $prefix is propagated to the AC_CONFIG_SUBDIRS configures.
961 Under the user pressure, $? is finally available. Probably a mistake.
962 - AC_F77_LIBRARY_LDFLAGS now supports the HP/UX f90 compiler.
963 - Precious variables accumulation
964 config.status could stack several copies of the precious variables
966 - AC_PATH_PROG and family.
967 Works properly when given a literal path.
969 Somewhere since 2.13, the result had been reversed.
973 - AC_C_BIGENDIAN supports the cross-compiling case.
974 - AC_C_BIGENDIAN accepts ACTION-IF-TRUE, ACTION-IF-FALSE, and
975 ACTION-IF-UNKNOWN arguments. All are facultative, and the default
976 for ACTION-IF-TRUE is to define WORDS_BIGENDIAN like AC_C_BIGENDIAN
978 - AC_C_LONG_DOUBLE now succeeds only if `long double' has more range or
979 precision than `double'.
984 It now defines the preprocessor symbols PACKAGE_NAME,
985 PACKAGE_TARNAME, PACKAGE_VERSION, PACKAGE_STRING, and
989 Admits a fourth optional parameter: the tar name.
991 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS.
992 Provide the user with srcdir, ac_srcdir, ac_top_srcdir, ac_builddir,
993 ac_top_builddir, ac_abs_srcdir, ac_abs_top_srcdir, ac_abs_builddir,
996 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS and AC_OUTPUT.
997 Are much less expensive when using long lists of files.
1000 Works with shell variables, and non alphanumeric names.
1004 - AC_FUNC_STRERROR_R now sets STRERROR_R_CHAR_P, not HAVE_WORKING_STRERROR_R,
1005 because POSIX 1003.1-200x draft 7 says strerror_r returns int, not char *.
1007 - AC_FUNC_STRTOD substitutes POW_LIB.
1012 * Major changes in Autoconf 2.52
1014 Released 2001-07-18 by Akim Demaille.
1019 This feature was present in autoconf 2.50 but was not documented.
1020 For example, `@<:@' is translated to `[' just before output. This
1021 is useful when writing strings that contain unbalanced quotes, or
1022 other hard-to-quote constructs.
1023 - m4_pattern_forbid, m4_pattern_allow
1024 - Tips for upgrading from 2.13.
1025 - Using autoscan to maintain a configure.ac.
1028 - Now include stdint.h.
1029 - sys/types.h and sys/stat.h are guarded.
1030 - strings.h is included if available, and not conflicting with string.h.
1033 - The test suite is more robust and presents less false failures.
1034 - Invocation of GNU M4 now robust to POSIXLY_CORRECT.
1035 - configure accepts --prefix='' again.
1036 - AC_CHECK_LIB works properly when its first argument is not a
1038 - HAVE_INTTYPES_H is defined only if not conflicting with sys/types.h.
1039 - build_, host_, and target_alias are AC_SUBST as in 2.13.
1040 - AC_ARG_VAR properly propagates precious variables inherited from the
1041 environment to ./config.status.
1042 - Using --program-suffix/--program-prefix is portable.
1043 - Failures to detect the default compiler's output extension are less
1045 - `config.status foo' works properly when `foo' depends on variables
1046 set in an AC_CONFIG_THING INIT-CMD.
1047 - autoheader is more robust to broken input.
1048 - Fixed Fortran name-mangling and link tests on a number of systems,
1049 e.g. NetBSD; see AC_F77_DUMMY_MAIN, below.
1052 - AC_CHECK_HEADER and AC_CHECK_HEADERS support a fourth argument to
1053 specify pre-includes. In this case, the headers are compiled with
1054 cc, not merely preprocessed by cpp. Therefore it is the _usability_
1055 of a header which is checked for, not just its availability.
1056 - AC_ARG_VAR refuses to run configure when precious variables have
1058 - Versions of compilers are dumped in the logs.
1059 - AC_CHECK_TYPE recognizes use of `foo_t' as a replacement type.
1062 - AC_PATH_XTRA only adds -ldnet to $LIBS if it's needed to link.
1063 - AC_FUNC_WAIT3 and AC_SYS_RESTARTABLE_SYSCALLS are obsoleted.
1064 - AM_FUNC_ERROR_AT_LINE, AM_FUNC_FNMATCH, AM_FUNC_MKTIME,
1065 AM_FUNC_OBSTACK, and AM_FUNC_STRTOD are now activated.
1066 Be sure to read `Upgrading from Version 2.13' to understand why
1067 running `autoupdate' is needed.
1068 - AC_F77_DUMMY_MAIN, AC_F77_MAIN: new macros to detect whether
1069 a main-like routine is required/possible when linking C/C++ with
1070 Fortran. Users of e.g. AC_F77_WRAPPERS should be aware of these.
1071 - AC_FUNC_GETPGRG behaves better when cross-compiling.
1073 * Major changes in Autoconf 2.51
1074 There was no release of Autoconf 2.51 since some packagers had used
1075 this version number without permission to ship intermediary versions
1076 of 2.50. The version was skipped to avoid confusion.
1078 * Major changes in Autoconf 2.50
1080 Released 2001-05-21 by Akim Demaille.
1082 ** Lots of bug fixes
1083 There have been far too many to enumerate them here. Check out
1084 ChangeLog if you really want to know more.
1086 ** Improved documentation
1087 In particular, portability issues are better covered.
1090 All the standard GNU Makefile targets are supported. The layout has
1091 changed: m4/ holds the M4 extensions Autoconf needs for its
1092 configuration, doc/ contains the documentation, and tests/ contains
1095 ** Man pages are provided
1096 For autoconf, autoreconf, autoupdate, autoheader, autoscan, ifnames,
1097 config.guess, config.sub.
1101 Provides a safe and powerful means to trace the macro uses. This
1102 provide the parsing layer for tools which need to `study'
1106 Specify what category of warnings should be enabled.
1108 - When recursing into subdirectories, try for configure.gnu before
1109 configure to adapt for packages not using autoconf on case-insensitive
1113 More errors are now caught (circular AC_REQUIRE dependencies,
1114 AC_DEFINE in the action part of an AC_CACHE_CHECK, too many pops
1115 etc.). In addition, their location and call stack are given.
1118 autoupdate is much more powerful, and is able to provide the glue code
1119 which might be needed to move from an old macro to its newer
1122 You are strongly encouraged to use it to modernize both your
1123 `configure.in' and your .m4 extension files.
1126 The internal machinery of autoheader has completely changed. As a
1127 result, using `acconfig.h' should be considered to be obsoleted, and
1128 you are encouraged to get rid of it using the AH macros.
1133 ** Fortran 77 compilers
1134 Globally, the support for Fortran 77 is considerably improved.
1136 Support for automatically determining a Fortran 77 compiler's
1137 name-mangling scheme. New CPP macros F77_FUNC and F77_FUNC_ are
1138 provided to wrap C/C++ identifiers, thus making it easier and more
1139 transparent for C/C++ to call Fortran 77 routines, and Fortran 77 to
1140 call C/C++ routines. See the Texinfo documentation for details.
1143 The test suite no longer uses DejaGNU. It should be easy to submit
1144 test cases in this new framework.
1147 - --help, --help=long, -hl
1148 no longer dumps useless items.
1150 lists only specific options.
1151 - --help=recursive, -hr
1152 displays the help of all the embedded packages.
1153 - Remembers environment variables when reconfiguring.
1154 The previous scheme to set envvar before running configure was
1156 what prevented configure from remembering the environment in which
1157 it was run, therefore --recheck was run in an inconsistent
1158 environment. Now, one should run
1160 and then --recheck will work properly. Variables declared with
1161 AC_ARG_VAR are also preserved.
1163 $build defaults to `config.guess`, $host to $build, and then $target
1165 Cross-compilation is a global status of the package, it no longer
1166 depends upon the current language.
1167 Cross compilation is enabled iff the user specified `--host'.
1168 `configure' now fails if it can't run the executables it compiles,
1169 unless cross-compilation is enabled.
1171 The cache file is disabled by default. The new options
1172 `--config-cache', `-C' set the cache to `config.cache'.
1176 Much faster on most architectures.
1177 - concurrent executions
1178 It is safe to use `make -j' with config.status.
1179 - human interface improved
1180 It is possible to invoke
1181 ./config.status foobar
1182 instead of the former form (still valid)
1183 CONFIG_COMMANDS= CONFIG_HEADERS= CONFIG_LINKS= \
1184 CONFIG_FILES=foobar:foo.in:bar.in \
1186 The same holds for configuration headers and links.
1187 You can instantiate unknown files and headers:
1188 ./config.status --header foo.h:foo.h.in --file bar:baz
1189 - has a useful --help
1190 - accepts special file name "-" for stdin/stdout
1195 Specify additional copyright information.
1198 Now expects the identity of the package as argument.
1202 Most macros, if not all, now strictly follow the `one quotation
1203 level' rule. This results in a more predictable expansion.
1206 A sly bug in the AC_REQUIRE machinery, which could produce incorrect
1207 configure scripts, was fixed by Axel Thimm.
1211 Document and ask for the registration of an envvar.
1214 Specifies the file which `configure' should look for when trying to
1215 find the source tree (used to be handled by AC_INIT).
1217 - AC_CONFIG_COMMANDS
1218 To add new actions to config.status. Should be used instead of
1222 Replaces AC_LINK_FILES.
1224 - AC_CONFIG_HEADERS, AC_CONFIG_COMMANDS, AC_CONFIG_SUBDIRS,
1225 AC_CONFIG_LINKS, and AC_CONFIG_FILES
1226 They now obey sh: you should no longer use shell variables as
1227 argument. Instead of
1229 test "$package_foo_enabled" = yes && $my_subdirs="$my_subdirs foo"
1230 AC_CONFIG_SUBDIRS($my_subdirs)
1234 if test "$package_foo_enabled" = yes; then
1235 AC_CONFIG_SUBDIRS(foo)
1239 To format an Autoconf macro's help string so that it looks pretty
1240 when the user executes `configure --help'.
1243 ** Generic Test Macros
1245 The interface of the AC_CHECK families of macros (decl, header,
1246 type, member, func) is now uniform. They support the same set of
1249 - AC_CHECK_DECL, AC_CHECK_DECLS
1250 To check whether a symbol is declared.
1252 - AC_CHECK_SIZEOF, AC_C_CHAR_UNSIGNED.
1253 No longer need a cross-compilation default.
1256 The test it performs is much more robust than previously, and makes
1257 it possible to test builtin types in addition to typedefs.
1258 It is now schizophrenic:
1259 - AC_CHECK_TYPE(TYPE, REPLACEMENT)
1260 remains for backward compatibility, but its use is discouraged.
1261 - AC_CHECK_TYPE(TYPE, IF-FOUND, IF-NOT-FOUND, INCLUDES)
1262 behaves exactly like the other AC_CHECK macros.
1265 Checks whether given types are supported by the system.
1267 - AC_CHECK_MEMBER, AC_CHECK_MEMBERS
1268 Check for given members in aggregates (e.g., pw_gecos in struct
1272 Checks if the compiler supports ISO C, included when needs special
1276 Checking whether the preprocessor indicates missing includes by the
1277 error code. stderr is checked by AC_TRY_CPP only as a fallback.
1280 Takes a language as argument and replaces AC_LANG_C,
1281 AC_LANG_CPLUSPLUS and AC_LANG_FORTRAN77.
1283 - AC_LANG_PUSH, AC_LANG_POP
1284 Are preferred to AC_LANG_SAVE, AC_LANG_RESTORE.
1287 - AC_FUNC_CHOWN, AC_FUNC_MALLOC, AC_FUNC_STRERROR_R,
1288 AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK, AC_FUNC_STAT, AC_FUNC_LSTAT,
1289 AC_FUNC_ERROR_AT_LINE, AC_FUNC_OBSTACK, AC_FUNC_STRTOD, AC_FUNC_FSEEKO.
1293 Sets GETGROUPS_LIBS.
1295 - AC_FUNC_GETLOADAVG
1296 Defines `HAVE_STRUCT_NLIST_N_UN_N_NAME' instead of `NLIST_NAME_UNION'.
1299 Now integrates `AC_DECL_YYTEXT' which is obsoleted.
1302 Arrange for large-file support.
1304 - AC_EXEEXT, AC_OBJEXT
1305 You are no longer expected to use them: their computation is
1306 performed by default.
1308 ** C++ compatibility
1309 Every macro has been revisited in order to support at best CC=c++.
1311 Major changes in Autoconf 2.14:
1312 There was no release of GNU Autoconf 2.14.
1314 Major changes in Autoconf 2.13:
1316 Released 1999-05-01 by Ben Elliston.
1318 * Support for building on Win32 systems where the only available C or
1319 C++ compiler is the Microsoft Visual C++ command line compiler
1320 (`cl'). Additional support for building on Win32 systems which are
1321 using the Cygwin or Mingw32 environments.
1322 * Support for alternative object file and executable file extensions.
1323 On Win32, for example, these are .obj and .exe. These are discovered
1324 using AC_OBJEXT and AC_EXEEXT, which substitute @OBJEXT@ and
1325 @EXEEXT@ in the output, respectively.
1326 * New macros: AC_CACHE_LOAD, AC_CACHE_SAVE, AC_FUNC_SELECT_ARGTYPES,
1327 AC_VALIDATE_CACHED_SYSTEM_TUPLE, AC_SEARCH_LIBS, AC_TRY_LINK_FUNC,
1328 AC_C_STRINGIZE, AC_CHECK_FILE(S), AC_PROG_F77 (and friends).
1329 * AC_DEFINE now has an optional third argument for a description to be
1330 placed in the config header input file (e.g. config.h.in).
1331 * The C++ code fragment compiled for the C++ compiler test had to be
1332 improved to include an explicit return type for main(). This was
1333 causing failures on systems using recent versions of the EGCS C++
1335 * Fixed an important bug in AC_CHECK_TYPE that would cause a configure
1336 script to report that `sometype_t' was present when only `type_t'
1338 * Merge of the FSF version of config.guess and config.sub to modernize
1339 these scripts. Add support for a few new hosts in config.guess.
1340 Incorporate latest versions of install-sh, mkinstalldirs and
1341 texinfo.tex from the FSF.
1342 * autoreconf is capable of running automake if necessary (and
1344 * Support for Fortran 77. See the Texinfo documentation for details.
1345 * Bug fixes and workarounds for quirky bugs in vendor utilities.
1347 Major changes in Autoconf 2.12:
1349 Released 1996-11-26 by David J. MacKenzie
1351 * AC_OUTPUT and AC_CONFIG_HEADER can create output files by
1352 concatenating multiple input files separated by colons, like so:
1353 AC_CONFIG_HEADER(config.h:conf.pre:config.h.in:conf.post)
1354 AC_OUTPUT(Makefile:Makefile.in:Makefile.rules)
1355 The arguments may be shell variables, to compute the lists on the fly.
1356 * AC_LINK_FILES and AC_CONFIG_SUBDIRS may be called multiple times.
1357 * New macro AC_OUTPUT_COMMANDS adds more commands to run in config.status.
1360 Major changes in Autoconf 2.11:
1362 Released November 18th, 1996, by David J. MacKenzie
1364 * AC_PROG_CC and AC_PROG_CXX check whether the compiler works.
1365 They also default CFLAGS/CXXFLAGS to "-g -O2" for gcc, instead of "-g -O".
1366 * AC_REPLACE_FUNCS defines HAVE_foo if the system has the function `foo'.
1367 * AC_CONFIG_HEADER expands shell variables in its argument.
1368 * New macros: AC_FUNC_FNMATCH, AC_FUNC_SETPGRP.
1369 * The "checking..." messages and the source code for test programs that
1370 fail are saved in config.log.
1371 * Another workaround has been added for seds with small command length limits.
1372 * config.sub and config.guess recognize more system types.
1375 Major changes in Autoconf 2.10:
1377 Released May 7th, 1996, by Roland McGrath
1380 * The cache variable names used by `AC_CHECK_LIB(LIB, FUNC, ...)' has
1381 changed: now $ac_cv_lib_LIB_FUNC, previously $ac_cv_lib_LIB.
1383 Major changes in Autoconf 2.9:
1385 Released March 16th, 1996, by Roland McGrath
1389 Major changes in Autoconf 2.8:
1391 Released March 8th, 1996, by Roland McGrath
1395 Major changes in Autoconf 2.7:
1397 Released November 22nd, 1995, by David J. MacKenzie
1401 Major changes in Autoconf 2.6:
1403 Released November 20th, 1995, by David J. MacKenzie
1407 Major changes in Autoconf 2.5:
1409 Released November 17th, 1995, by Roland McGrath
1411 * New configure options --bindir, --libdir, --datadir, etc., with
1412 corresponding output variables.
1413 * New macro: AC_CACHE_CHECK, to make using the cache easier.
1414 * config.log contains the command being run as well as any output from it.
1415 * AC_CHECK_LIB can check for libraries with "." or "/" or "+" in their name.
1416 * AC_PROG_INSTALL doesn't cache a name for install-sh, for sharing caches.
1417 * AC_CHECK_PROG, AC_PATH_PROG, AC_CHECK_PROGS, AC_PATH_PROGS, and
1418 AC_CHECK_TOOL can search a path other than $PATH.
1419 * AC_CHECK_SIZEOF takes an optional size to use when cross-compiling.
1421 Major changes in Autoconf 2.4:
1423 Released June 14th, 1995, by David J. MacKenzie
1425 * Fix a few bugs found by Emacs testers.
1427 Major changes in Autoconf 2.3:
1429 Released March 27th, 1995, by David J. MacKenzie
1431 * Fix the cleanup trap in several ways.
1432 * Handle C compilers that are picky about option placement.
1433 * ifnames gets the version number from the right directory.
1435 Major changes in Autoconf 2.2:
1437 Released March 8th, 1995, by David J. MacKenzie
1439 * The ifnames utility is much faster but requires a "new awk" interpreter.
1440 * AC_CHECK_LIB and AC_HAVE_LIBRARY check and add the new
1441 library before existing libs, not after, in case it uses them.
1442 * New macros: AC_FUNC_GETPGRP, AC_CHECK_TOOL.
1443 * Lots of bug fixes.
1444 * Many additions to the TODO file :-)
1446 Major changes in Autoconf 2.1:
1448 Released November 4th, 1994, by David J. MacKenzie
1451 * More explanations in the manual.
1452 * Fix a spurious failure in the testsuite.
1453 * Clarify some warning messages.
1454 * autoreconf by default only rebuilds configure and config.h.in files
1455 that are older than any of their particular input files; there is a
1456 --force option to use after installing a new version of Autoconf.
1458 Thanks to everybody who's submitted changes and additions to Autoconf!
1459 I've incorporated many of them, and am still considering others for
1460 future releases -- but I didn't want to postpone this release indefinitely.
1462 Caution: don't indiscriminately rebuild configure scripts with
1463 Autoconf version 2. Some configure.in files need minor adjustments to
1464 work with it; the documentation has a chapter on upgrading. A few
1465 configure.in files, including those for GNU Emacs and the GNU C
1466 Library, need major changes because they relied on undocumented
1467 internals of version 1. Future releases of those packages will have
1468 updated configure.in files.
1470 It's best to use GNU M4 1.3 (or later) with Autoconf version 2.
1471 Autoconf now makes heavy use of M4 diversions, which were implemented
1472 inefficiently in GNU M4 releases before 1.3.
1474 Major changes in Autoconf 2.0:
1476 Released October 26th, 1994, by David J. MacKenzie
1478 ** New copyright terms:
1479 * There are no restrictions on distribution or use of configure scripts.
1482 * Autoconf manual is reorganized to make information easier to find
1483 and has several new indexes.
1484 * INSTALL is reorganized and clearer and is now made from Texinfo source.
1487 * autoscan to generate a preliminary configure.in for a package by
1488 scanning its source code for commonly used nonportable functions,
1489 programs, and header files.
1490 * ifnames to list the symbols used in #if and #ifdef directives in a
1492 * autoupdate to update a configure.in to use the version 2 macro names.
1493 * autoreconf to recursively remake configure and configuration header
1494 files in a source tree.
1496 ** Changed utilities:
1497 * autoheader can take pieces of acconfig.h to replace config.h.{top,bot}.
1498 * autoconf and autoheader can look for package-local definition files
1499 in an alternate directory.
1502 * AC_CACHE_VAL to share results of tests between configure runs.
1503 * AC_DEFUN to define macros, automatically AC_PROVIDE them, and ensure
1504 that macros invoked with AC_REQUIRE don't interrupt other macros.
1505 * AC_CONFIG_AUX_DIR, AC_CANONICAL_SYSTEM, AC_CANONICAL_HOST, AC_LINK_FILES to
1506 support deciding unguessable features based on the host and target types.
1507 * AC_CONFIG_SUBDIRS to recursively configure a source tree.
1508 * AC_ARG_PROGRAM to use the options --program-prefix,
1509 --program-suffix, and --program-transform-name to change the names
1510 of programs being installed.
1511 * AC_PREFIX_DEFAULT to change the default installation prefix.
1512 * AC_TRY_COMPILE to compile a test program without linking it.
1513 * AC_CHECK_TYPE to check whether sys/types.h or stdlib.h defines a given type.
1514 * AC_CHECK_LIB to check for a particular function and library.
1515 * AC_MSG_CHECKING and AC_MSG_RESULT to print test results, on a single line,
1516 whether or not the test succeeds. They obsolete AC_CHECKING and AC_VERBOSE.
1517 * AC_SUBST_FILE to insert one file into another.
1518 * AC_FUNC_MEMCMP to check whether memcmp is 8-bit clean.
1519 * AC_FUNC_STRFTIME to find strftime even if it's in -lintl.
1520 * AC_FUNC_GETMNTENT to find getmntent even if it's in -lsun or -lseq.
1521 * AC_HEADER_SYS_WAIT to check whether sys/wait.h is POSIX.1 compatible.
1524 * Many macros renamed systematically, but old names are accepted for
1525 backward compatibility.
1526 * AC_OUTPUT adds the "automatically generated" comment to
1527 non-Makefiles where it finds @configure_input@ in an input file, to
1528 support files with various comment syntaxes.
1529 * AC_OUTPUT does not replace "prefix" and "exec_prefix" in generated
1530 files when they are not enclosed in @ signs.
1531 * AC_OUTPUT allows the optional environment variable CONFIG_STATUS to
1532 override the file name "config.status".
1533 * AC_OUTPUT takes an optional argument for passing variables from
1534 configure to config.status.
1535 * AC_OUTPUT and AC_CONFIG_HEADER allow you to override the input-file names.
1536 * AC_OUTPUT automatically substitutes the values of CFLAGS, CXXFLAGS,
1537 CPPFLAGS, and LDFLAGS from the environment.
1538 * AC_PROG_CC and AC_PROG_CXX now set CFLAGS and CXXFLAGS, respectively.
1539 * AC_PROG_INSTALL looks for install-sh or install.sh in the directory
1540 specified by AC_CONFIG_AUXDIR, or srcdir or srcdir/.. or
1541 srcdir/../.. by default.
1542 * AC_DEFINE, AC_DEFINE_UNQUOTED, and AC_SUBST are more robust and smaller.
1543 * AC_DEFINE no longer prints anything, because of the new result reporting
1544 mechanism (AC_MSG_CHECKING and AC_MSG_RESULT).
1545 * AC_VERBOSE pays attention to --quiet/--silent, not --verbose.
1546 * AC_ARG_ENABLE and AC_ARG_WITH support whitespace in the arguments to
1547 --enable- and --with- options.
1548 * AC_CHECK_FUNCS and AC_CHECK_HEADERS take optional shell commands to
1549 execute on success or failure.
1550 * Checking for C functions in C++ works.
1553 * AC_REMOTE_TAPE and AC_RSH removed; too specific to tar and cpio, and
1554 better maintained with them.
1555 * AC_ARG_ARRAY removed because no one was likely using it.
1556 * AC_HAVE_POUNDBANG replaced with AC_SYS_INTERPRETER, which doesn't
1557 take arguments, for consistency with all of the other specific checks.
1560 * Comes with config.sub and config.guess, and uses them optionally.
1561 * Uses config.cache to cache test results. An alternate cache file
1562 can be selected with the --cache-file=FILE option.
1563 * Uses optional shell scripts $prefix/share/config.site and
1564 $prefix/etc/config.site to perform site or system specific initializations.
1565 * configure saves compiler output to ./config.log for debugging.
1566 * New files autoconf.m4 and autoheader.m4 load the other Autoconf macros.
1567 * acsite.m4 is the new name for the system-wide aclocal.m4.
1568 * Has a DejaGnu test suite.
1570 Major changes in Autoconf 1.11:
1572 * AC_PROG_INSTALL calls install.sh with the -c option.
1573 * AC_SET_MAKE cleans up after itself.
1574 * AC_OUTPUT sets prefix and exec_prefix if they weren't set already.
1575 * AC_OUTPUT prevents shells from looking in PATH for config.status.
1577 Plus a few other bug fixes.
1579 Major changes in Autoconf 1.10:
1581 * autoheader uses config.h.bot if present, analogous to config.h.top.
1582 * AC_PROG_INSTALL looks for install.sh in srcdir or srcdir/.. and
1584 * AC_PROG_CXX looks for cxx as a C++ compiler.
1586 Plus several bugs fixed.
1588 Major changes in Autoconf 1.9:
1590 * AC_YYTEXT_POINTER replaces AC_DECLARE_YYTEXT.
1591 * AC_SIZEOF_TYPE generates the cpp symbol name automatically,
1592 and autoheader generates entries for those names automatically.
1593 * AC_FIND_X gets the result from xmkmf correctly.
1594 * AC_FIND_X assumes no X if --without-x was given.
1595 * AC_FIND_XTRA adds libraries to the variable X_EXTRA_LIBS.
1596 * AC_PROG_INSTALL finds OSF/1 installbsd.
1598 Major changes in Autoconf 1.8:
1601 * New macros AC_LANG_C, AC_LANG_CPLUSPLUS, AC_LANG_SAVE, AC_LANG_RESTORE,
1602 AC_PROG_CXX, AC_PROG_CXXCPP, AC_REQUIRE_CPP
1603 for checking both C++ and C features in one configure script.
1604 * New macros AC_CHECKING, AC_VERBOSE, AC_WARN, AC_ERROR for printing messages.
1605 * New macros AC_FIND_XTRA, AC_MMAP, AC_SIZEOF_TYPE, AC_PREREQ,
1606 AC_SET_MAKE, AC_ENABLE.
1609 * AC_FIND_X looks for X in more places.
1610 * AC_PROG_INSTALL defaults to install.sh instead of cp, if it's in srcdir.
1611 install.sh is distributed with Autoconf.
1612 * AC_DECLARE_YYTEXT has been removed because it can't work, pending
1613 a rewrite of quoting in AC_DEFINE.
1614 * AC_OUTPUT adds its comments in C format when substituting in C files.
1615 * AC_COMPILE_CHECK protects its ECHO-TEXT argument with double quotes.
1617 ** New or changed command line options:
1618 * configure accepts --enable-FEATURE[=ARG] and --disable-FEATURE options.
1619 * configure accepts --without-PACKAGE, which sets withval=no.
1620 * configure accepts --x-includes=DIR and --x-libraries=DIR.
1621 * Giving --with-PACKAGE no argument sets withval=yes instead of withval=1.
1622 * configure accepts --help, --version, --silent/--quiet, --no-create options.
1623 * configure accepts and ignores most other Cygnus configure options, and
1624 warns about unknown options.
1625 * config.status accepts --help, --version options.
1627 ** File names and other changes:
1628 * Relative srcdir values are not made absolute.
1629 * The values of @prefix@ and @exec_prefix@ and @top_srcdir@ get substituted.
1630 * Autoconf library files are installed in ${datadir}/autoconf, not ${datadir}.
1631 * autoheader optionally copies config.h.top to the beginning of config.h.in.
1632 * The example Makefile dependencies for configure et al. work better.
1633 * Namespace cleanup: all shell variables used internally by Autoconf
1634 have names beginning with `ac_'.
1636 More big improvements are in process for future releases, but have not
1637 yet been (variously) finished, integrated, tested, or documented enough
1640 Major changes in Autoconf 1.7:
1642 * New macro AC_OBSOLETE.
1643 * Bugs in Makefile.in fixed.
1644 * AC_LONG_FILE_NAMES improved.
1646 Major changes in Autoconf 1.6:
1648 * New macro AC_LONG_64_BITS.
1649 * Multiple .h files can be created.
1650 * AC_FIND_X looks for X files directly if it doesn't find xmkmf.
1651 * AC_ALLOCA defines C_ALLOCA if using alloca.c.
1652 * --with-NAME can take a value, e.g., --with-targets=sun4,hp300bsd.
1653 * Unused --no-create option to configure removed.
1654 * autoheader doesn't change the timestamp of its output file if
1655 the file didn't change.
1656 * All macros that look for libraries now use AC_HAVE_LIBRARY.
1657 * config.status checks three optional environment variables to
1658 modify its behavior.
1659 * The usual bug fixes.
1661 Major changes in Autoconf 1.5:
1663 * New macros AC_FIND_X, AC_OFF_T, AC_STAT_MACROS_BROKEN, AC_REVISION.
1664 * autoconf and autoheader scripts have GNU standards conforming
1665 --version and --help options (they print their message and exit).
1668 Major changes in Autoconf 1.4:
1670 * New macros AC_HAVE_POUNDBANG, AC_TIME_WITH_SYS_TIME, AC_LONG_DOUBLE,
1671 AC_GETGROUPS_T, AC_DEFINE_UNQUOTED.
1672 * autoconf and autoheader use the M4 environment variable to determine the
1673 name of the M4 program to use.
1674 * The --macrodir option to autoconf and autoheader specifies the directory
1675 in which acspecific.m4, acgeneral.m4, etc. reside if not the default.
1676 * autoconf and autoheader can take `-' as their file names, which means to
1677 read stdin as input.
1678 * Resulting configure scripts can take a --verbose option which causes them
1679 to print the results of their tests.
1680 * AC_DEFINE quotes its second argument in such a way that spaces, magic
1681 shell characters, etc. will be preserved during various stages of
1682 expansion done by the shell. If you don't want this, use
1683 AC_DEFINE_UNQUOTED instead.
1684 * Much textual processing done with external calls to tr and sed have been
1685 internalized with builtin M4 `patsubst' and `translit' calls.
1686 * AC_OUTPUT doesn't hardwire the file names it outputs. Instead, you can
1687 set the shell variables `gen_files' and `gen_config' to the list of
1688 file names to output.
1689 * AC_DECLARE_YYTEXT does an AC_SUBST of `LEX_OUTPUT_ROOT', which may be
1690 "lex.yy" or "lexyy", depending on the system.
1691 * AC_PROGRAMS_CHECK takes an optional third arg. If given, it is used as
1693 * If AC_ALLOCA chooses alloca.c, it also defines STACK_DIRECTION.
1694 * AC_CONST works much more reliably on more systems.
1697 Major changes in Autoconf 1.3:
1699 configure no longer requires awk for packages that use a config.h.
1700 Support handling --with-PACKAGE options.
1701 New `autoheader' script to create `config.h.in' from `configure.in'.
1702 Ignore troublesome -lucb and -lPW when searching for alloca.
1703 Rename --exec_prefix to --exec-prefix for GNU standards conformance.
1704 Improve detection of STDC library.
1705 Add AC_HAVE_LIBRARY to check for non-default libraries.
1706 Function checking should work with future GNU libc releases.
1708 Major changes in Autoconf 1.2:
1710 The --srcdir option is now usually unnecessary.
1711 Add a file containing sample comments describing CPP macros.
1712 A comment in config.status tells which host it was configured on.
1713 Substituted variable values can now contain commas.
1714 Fix bugs in various feature checks.
1716 Major changes in Autoconf 1.1:
1718 Added AC_STRCOLL macro.
1719 Made AC_GETLOADAVG check for more things.
1720 AC_OUTPUT argument is now optional.
1725 Copyright (C) 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002,
1726 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
1728 This program is free software: you can redistribute it and/or modify
1729 it under the terms of the GNU General Public License as published by
1730 the Free Software Foundation, either version 3 of the License, or
1731 (at your option) any later version.
1733 This program is distributed in the hope that it will be useful,
1734 but WITHOUT ANY WARRANTY; without even the implied warranty of
1735 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1736 GNU General Public License for more details.
1738 You should have received a copy of the GNU General Public License
1739 along with this program. If not, see <http://www.gnu.org/licenses/>.