1 GNU Autoconf NEWS - User visible changes.
3 * Noteworthy changes in release ?.? (????-??-??) [?]
5 ** Support for the Go programming language has been added. The new macro
6 AC_LANG_GO sets variables GOC and GOFLAGS.
8 ** AS_LITERAL_IF again treats '=' as a literal. Regression introduced in
13 - New macro AC_HEADER_CHECK_STDBOOL.
15 - New and updated macros for Fortran support:
17 AC_FC_CHECK_BOUNDS to enable array bounds checking
18 AC_F77_IMPLICIT_NONE and AC_FC_IMPLICIT_NONE to disable implicit integer
19 AC_FC_MODULE_EXTENSION to compute the Fortran 90 module name extension
20 AC_FC_MODULE_FLAG for the Fortran 90 module search path flag
21 AC_FC_MODULE_OUTPUT_FLAG for the Fortran 90 module output directory flag
22 AC_FC_PP_SRCEXT for preprocessed Fortran source files extensions
23 AC_FC_PP_DEFINE for the Fortran preprocessor define flag
25 * Noteworthy changes in release 2.68 (2010-09-22) [stable]
26 Released by Eric Blake, based on git versions 2.67.*.
28 ** AC_MSG_ERROR (and AS_ERROR) can once again be followed immediately by
29 `dnl'. Regression introduced in 2.66.
31 ** AC_INIT again allows URLs with '?' for its BUG-REPORT argument.
32 Regression introduced in 2.66.
34 ** AC_REPLACE_FUNCS again allows a non-literal argument, such as a shell
35 variable that expands to a list of functions to check. Regression
38 ** AT_BANNER() with empty argument will cause visual separation from previous
41 ** The macros AC_PREPROC_IFELSE, AC_COMPILE_IFELSE, AC_LINK_IFELSE, and
42 AC_RUN_IFELSE now warn if the first argument failed to use
43 AC_LANG_SOURCE or AC_LANG_PROGRAM to generate the conftest file
44 contents. A new macro AC_LANG_DEFINES_PROVIDED exists if you have
45 a compelling reason why you cannot use AC_LANG_SOURCE but must
48 ** The macro m4_define_default is now documented.
50 ** Symlinked config.cache files are supported; configure now tries to
51 update non-symlinked cache files atomically, so that concurrent configure
52 runs do not leave behind broken cache files. It is still unspecified
53 which subset or union of results is cached though.
55 ** Autotest testsuites should not contain long text lines any more, and be
56 portable even when very many test groups are used.
58 ** AT_CHECK semantics with respect to the Autotest variable $at_status and
59 shell execution environment of the arguments are documented now.
61 ** AC_FC_LIBRARY_LDFLAGS now tolerates output from newer gfortran.
63 ** Newly obsolete macros
64 The following macros have been marked obsolete. New programs
65 should use the corresponding Gnulib modules. Gnulib not only
66 detects a larger set of portability problems with these functions,
67 but also provides complete workarounds.
69 AC_FUNC_ERROR_AT_LINE AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK
70 AC_FUNC_MKTIME AC_FUNC_STRTOD
73 * Major changes in Autoconf 2.67 (2010-07-21) [stable]
74 Released by Eric Blake, based on git versions 2.66.*.
76 ** AC_CONFIG_SUBDIRS with more than one subdirectory at a time works again.
77 Regression introduced in 2.66.
79 ** AC_CHECK_SIZEOF of a pointer type works again. Regression introduced in
82 ** New macro AC_FC_LINE_LENGTH to accept long Fortran source code lines.
84 ** AC_PREPROC_IFELSE now keeps the preprocessed output in the conftest.i
85 file for inspection by the commands in the ACTION-IF-TRUE argument.
87 ** AC_INIT again allows parentheses and other characters that are literal
88 in single- or double-quoted strings, and in quoted and unquoted
89 here-documents, for its PACKAGE and VERSION arguments. Regression
92 ** autoreconf passes warning flags to new enough versions of aclocal.
94 ** Running an Autotest testsuite in parallel mode no longer triggers a
95 race condition that could cause the testsuite run to end early,
96 fixing a sporadic failure in autoconf's own testsuite. Bug present
97 since introduction of parallel tests in 2.63b.
100 * Major changes in Autoconf 2.66 (2010-07-02) [stable]
101 Released by Eric Blake, based on git versions 2.65.*.
103 ** AC_FUNC_MMAP works in C++ mode again. Regression introduced in 2.65.
105 ** Use of m4_divert without a named diversion now issues a syntax warning,
106 since it is seldom right to change diversions behind autoconf's back.
108 ** The macros AC_TYPE_INT8_T, AC_TYPE_INT16_T, AC_TYPE_INT32_T, and
109 AC_TYPE_INT64_T work again. Regression introduced in 2.65.
111 ** AC_PROG_INSTALL correctly uses `shtool' again. Regression introduced
114 ** Autoconf should work on EBCDIC hosts.
116 ** AC_CHECK_DECL and AC_CHECK_DECLS accept optional function argument types
117 for overloaded C++ functions.
119 ** AS_SET_CATFILE accepts nonliterals in its variable name argument now.
121 ** Autotest testsuites accept an option --recheck to rerun tests that
122 failed or passed unexpectedly during the last non-debug testsuite run.
124 ** AC_ARG_ENABLE and AC_ARG_WITH now also accept `+' signs in `--enable-*'
125 and `--with-*' arguments, converting them to underscores for the variable
128 ** In configure scripts, loading CONFIG_SITE no longer searches PATH,
129 and problems in loading the configuration site files are diagnosed.
131 ** Autotest testsuites may optionally provide colored test results.
133 ** The previously undocumented Autotest macros AT_ARG_OPTION and
134 AT_ARG_OPTION_ARG have seen bug fixes and are documented now.
135 AT_ARG_OPTION has been changed in that the negative of a long option
136 --OPTION is now --no-OPTION rather than --noOPTION.
138 ** The macro AS_LITERAL_IF is slightly more conservative; text
139 containing shell quotes are no longer treated as literals.
140 Furthermore, a new macro, AS_LITERAL_WORD_IF, adds an additional
141 level of checking that no whitespace occurs in literals.
143 ** The macros AS_TR_SH and AS_TR_CPP no longer expand their results.
145 ** The following macros are now documented:
148 ** New macro AC_FC_FIXEDFORM to accept fixed-form Fortran.
151 * Major changes in Autoconf 2.65 (2009-11-21) [stable]
152 Released by Eric Blake, based on git versions 2.64.*.
154 ** Autoconf is now licensed under the General Public License version 3
155 or later (GPLv3+). As with earlier versions, the license includes
156 an exception clause so that you may release a configure script
157 generated by autoconf under the license of your own program.
159 ** New macros to support Objective C++.
160 AC_PROG_OBJCXX AC_PROG_OBJCXXCPP
162 ** The following undocumented autoconf macros, removed in Autoconf 2.64,
163 have been reinstated:
166 These macros are present only for backwards compatibility purposes.
168 ** The macro AC_LANG_COMPILER no longer fails on embedded systems that
169 lack fopen in the C library, such as AVR or RTEMS (regression
172 ** The AC_FC_FREEFORM macro no longer suffers from a whitespace bug that
173 made it fail with some Fortran compilers (regression introduced in
176 ** The AC_TYPE_UINT64_T and AC_TYPE_INT64_T macros have been fixed to no
177 longer mistakenly select a 32-bit type on some compilers (bug present
178 since macros were introduced in 2.59c).
180 ** The AC_FUNC_MMAP macro has been fixed to be portable to systems like
181 Cygwin (bug present since macro was introduced in 2.0).
183 ** The following documented autotest macros are new:
186 ** The following m4sugar macros now quote their expansion:
187 m4_toupper m4_tolower
189 ** The following m4sugar macros are new:
192 ** The m4sugar macro m4_text_wrap now copes with embedded quoting without
193 requiring quadrigraphs. For uses like AC_ARG_VAR([a], [[b c]]),
194 this gives the intuitive behavior of "[b c]" in the output (2.63
195 gave the output of "[b], [c]", and 2.64 encountered a failure).
197 ** The `$tmp' temporary directory used in config.status is documented for
200 ** config.status now provides a --config option to produce the configuration.
202 ** Many cache variables used by Autoconf's macros are now documented.
204 ** Configure scripts work better on DJGPP by avoiding a bug present in
205 the DJGPP port of bash 2.04 in handling 'return' in a shell
206 function (regression introduced in 2.64).
208 * Major changes in Autoconf 2.64 (2009-07-26) [stable]
209 Released by Eric Blake, based on git versions 2.63b.*.
211 ** Autoconf now requires GNU M4 1.4.6 or later. Earlier versions of M4
212 have a bug in regular expression handling that interferes with some
213 of the speedups provided since Autoconf 2.63. GNU M4 1.4.13 or
214 later is recommended.
216 ** AS_IF and AS_CASE have been taught to avoid syntax errors even when
217 given arguments that expand to just whitespace.
219 ** The following documented autoconf macros are new:
220 AC_ERLANG_SUBST_ERTS_VER
222 ** The autoheader tool now understands m4 macro arguments passed to
223 AC_DEFINE and AC_DEFINE_UNQUOTED.
225 ** Ensure AT_CHECK can support commands that include a # given with
226 proper m4 quoting. For shell comments, this is a new feature; for
227 non-shell comments, this fixes a regression introduced in 2.63b.
228 Additionally, AT_CHECK correctly supplies shell escapes for
229 metacharacters occurring in m4 macro expansions within the expected
230 stdout and stderr parameters.
232 ** The macro AT_CHECK now understands the concept of hard failure. If
233 a test exits with an unexpected status 99, cleanup actions for the
234 test are inhibited and the test is treated as a failure regardless
235 of AT_XFAIL_IF. It also understands the new directives
236 ignore-nolog, stdout-nolog, and stderr-nolog.
238 ** The following documented autotest macros are new:
239 AT_CHECK_UNQUOTED AT_FAIL_IF AT_SKIP_IF
241 ** The following documented m4sugar macros are new:
242 m4_argn m4_copy_force m4_default_nblank m4_default_nblank_quoted
243 m4_ifblank m4_ifnblank m4_rename_force
245 ** The autoconf testsuite now exercises all Erlang macros.
247 * Major changes in Autoconf 2.63b (2009-03-31) [beta]
248 Released by Eric Blake, based on git versions 2.63.*.
250 ** The manual is now shipped under the terms of the GNU FDL 1.3.
252 ** AC_REQUIRE now detects the case of an outer macro which first expands
253 then later indirectly requires the same inner macro. Previously,
254 this case led to silent out-of-order expansion (bug present since
255 2.50); it now issues a syntax warning, and duplicates the expansion
256 of the inner macro to guarantee dependencies have been met. See
257 the manual for advice on how to refactor macros in order to avoid
258 the bug in earlier autoconf versions and avoid increased script
259 size in the current version.
261 ** AC_DEFUN_ONCE has improved semantics. Previously, a macro declared
262 with AC_DEFUN_ONCE warned on a second invocation; and out-of-order
263 expansion was still possible. Now, dependencies are guaranteed,
264 and subsequent invocations are a silent no-op. This makes
265 AC_DEFUN_ONCE an ideal macro for silencing AC_REQUIRE warnings.
267 ** The following macros are now defined with AC_DEFUN_ONCE. This means
268 a subtle change in semantics; previously, an AC_DEFUN macro could
269 expand one of these macros multiple times or surround the macro
270 inside shell conditional text to bypass the effects of these
271 macros, but now the macro will expand exactly once, and prior to
272 the start of any enclosing AC_DEFUN macro:
273 AC_CANONICAL_BUILD AC_CANONICAL_HOST AC_CANONICAL_TARGET
274 AC_HEADER_ASSERT AC_PROG_INSTALL AC_PROG_MKDIR_P
275 AC_USE_SYSTEM_EXTENSIONS
277 ** AC_LANG_ERLANG works once again (regression introduced in 2.61a).
279 ** AC_HEADER_ASSERT is fixed so that './configure --enable-assert' no
280 longer mistakenly disables assertions.
282 ** AC_INIT now takes an optional fifth parameter that can be used to
283 set AC_PACKAGE_URL, a URL for the package's home page; the URL is
284 used in `configure --help' and is also available via AC_DEFINE.
286 ** Autotest testsuites accept an option --jobs[=N] for parallel testing.
287 This feature is still in testing, and may not work on every
288 platform, help in improving it would be appreciated.
290 ** Autotest testsuites do not attempt to write startup error messages
291 to the log file before that is opened (regression introduced in 2.63).
293 ** Configure scripts now use shell functions. This feature leads to
294 smaller configure files and faster execution.
296 ** Present But Cannot Be Compiled: Autoconf will now proceed with
297 the compiler's result if a header is present but cannot be compiled.
298 The warning is still printed, and you should really fix it by
299 providing a fourth parameter to AC_CHECK_HEADER/AC_CHECK_HEADERS.
301 ** Autoreconf added aclocal to the set of programs affected by the
302 `autoreconf -I dir' option.
304 ** The following documented m4sugar macros are new:
305 m4_chomp m4_chomp_all m4_cleardivert m4_curry m4_default_quoted
306 m4_esyscmd_s m4_map_args m4_map_args_pair m4_map_args_sep
307 m4_map_args_w m4_set_map m4_set_map_sep m4_stack_foreach
308 m4_stack_foreach_lifo m4_stack_foreach_sep
309 m4_stack_foreach_sep_lifo
311 ** The following m4sugar macros are documented now, but in some cases
312 with slightly different semantics than what the previous
313 undocumented version had:
314 m4_copy m4_dumpdefs m4_rename m4_version_prereq
316 ** The m4sugar macro m4_expand has been taught to handle unterminated
317 comments and shell case statements. As a result, it is used
318 internally in more places, such as AC_DEFINE and AT_CHECK. Most
319 uses of AC_DEFINE and AT_CHECK should not behave any differently;
320 however, it may be necessary to add double-quoting around
321 unbalanced `(' where single-quoting used to be sufficient.
323 ** The following documented m4sh macros are new:
324 AS_INIT_GENERATED AS_LINENO_PREPARE AS_ME_PREPARE AS_SET_STATUS
325 AS_VAR_APPEND AS_VAR_ARITH AS_VAR_COPY
327 ** The following m4sh macros are documented now, but in some cases
328 with slightly different semantics than what the previous
329 undocumented version had:
330 AS_ECHO AS_ECHO_N AS_ESCAPE AS_EXIT AS_LITERAL_IF AS_UNSET
331 AS_VAR_IF AS_VAR_POPDEF AS_VAR_PUSHDEF AS_VAR_SET AS_VAR_SET_IF
332 AS_VAR_TEST_SET AS_VERSION_COMPARE
334 ** The m4sh macros AS_IF and AS_CASE can now be used in shell lists.
335 The responsibility for supplying a trailing newline now belongs to
336 the call site, but since most users did not add dnl, this generally
337 results in fewer empty lines in configure.
340 * Major changes in Autoconf 2.63 (2008-09-09) [stable]
341 Released by Eric Blake, based on git versions 2.62.*.
343 ** AC_C_BIGENDIAN does not mistakenly report "universal" for some
344 bigendian hosts, a regression introduced with universal binary
347 ** AC_PATH_X now includes /lib64 and /usr/lib64 in its list of default
350 ** AC_USE_SYSTEM_EXTENSIONS no longer conflicts with an external
351 AC_DEFINE([__EXTENSIONS__]). This fixes a regression introduced in
352 2.62 when using macros such as AC_AIX that were made obsolete in
353 favor of the more portable AC_USE_SYSTEM_EXTENSIONS.
355 ** AC_CHECK_TARGET_TOOLS is usable in the non-cross-compile case.
357 ** Newly obsolete macros
358 The following macro has been marked obsolete, since current porting
359 targets can safely assume C89 semantics that signal handlers return
360 void. We have no current plans to remove the macro.
364 ** The macros m4_map and m4_map_sep now ignore any list elements
365 consisting of just empty quotes, and m4_map_sep now expands its
366 separator. This fixes a regression in 2.62 when these macros were
367 first documented, for the sake of clients expecting the semantics
368 that these macros had prior to that time. The new macros m4_mapall
369 and m4_mapall_sep, along with extra quoting of the separator, can
370 be used to get the semantics that m4_map_sep had in 2.62.
372 ** Clients of m4_expand, such as AS_HELP_STRING and AT_SETUP, can now
373 handle properly quoted but otherwise unbalanced parentheses (for
374 some macros, this fixes a regression in 2.62).
376 ** Two new quadrigraphs have been introduced: @{:@ for (, and @:}@ for ),
377 allowing the output of unbalanced parentheses in more contexts.
379 ** The following m4sugar macros are new:
380 m4_cleardivert m4_joinall m4_mapall m4_mapall_sep m4_reverse
381 m4_set_add m4_set_add_all m4_set_contains m4_set_contents
382 m4_set_delete m4_set_difference m4_set_dump m4_set_empty
383 m4_set_foreach m4_set_intersection m4_set_list m4_set_listc
384 m4_set_remove m4_set_size m4_set_union
386 ** The following m4sugar macros now accept multiple arguments, as is the
387 case with underlying m4:
388 m4_defn m4_popdef m4_undefine
390 ** The following m4sugar macros now guarantee linear scaling; they
391 previously had linear scaling with m4 1.6 but quadratic scaling
392 when using m4 1.4.x. All macros built on top of these also gain
393 the scaling improvements.
394 m4_bmatch m4_bpatsubsts m4_case m4_cond m4_do m4_dquote_elt
395 m4_foreach m4_join m4_list_cmp m4_map m4_map_sep m4_max
398 ** AT_KEYWORDS once again performs expansion on its argument, such that
399 AT_KEYWORDS([m4_if([$1], [], [default])]) no longer complains about
400 the possibly unexpanded m4_if [regression introduced in 2.62].
402 ** Config header templates `#undef UNDEFINED /* comment */' do not lead to
403 nested comments any more; regression introduced in 2.62.
406 * Major changes in Autoconf 2.62 (2008-04-05) [stable]
407 Released by Eric Blake, based on git versions 2.61a.*.
409 ** Many optimizations have been applied to make overall execution faster.
411 ** Autotest now makes use of shell functions.
413 ** config.status now uses awk instead of sed also for config headers.
415 - As a side effect, AC_DEFINE and AC_DEFINE_UNQUOTED now handle multi-line
416 values, i.e., backslash-newline combinations are handled correctly.
417 Further, for config headers, the total size of values is not limited by
418 the POSIX length limit of text lines any more, only each single line.
420 ** New config variable `top_build_prefix'.
422 ** New Autoconf macros:
423 AC_AUTOCONF_VERSION AC_OPENMP AC_PATH_PROGS_FEATURE_CHECK
425 ** AC_C_BIGENDIAN now supports universal binaries a la Mac OS X.
427 ** AC_C_RESTRICT now prefers to #define 'restrict' to a variant spelling
428 like '__restrict' if the variant spelling is available, as this is
429 more likely to work when mixing C and C++ code.
431 ** AC_CHECK_ALIGNOF's type argument T is now documented better: it must
432 be a string of tokens such that "T y;" is a valid member declaration
435 ** AC_CHECK_SIZEOF now accepts objects as well as types: the general rule
436 is that sizeof (X) works, then AC_CHECK_SIZEOF (X) should work.
438 ** AC_CHECK_TYPE and AC_CHECK_TYPES now work on any C type-name; formerly,
439 they did not work for function types. In C++, they now work on any
440 type-id that can be the operand of sizeof; this is similar to C,
441 except it excludes anonymous struct and union types. Formerly,
442 some (but not all) C++ types involving anonymous struct and union
443 were accepted, though this was not documented.
445 ** AC_CONFIG_LINKS now prefers to link against files in the build tree
446 if found, and it works to link against a file of the same name in
447 the source tree, even if both trees coincide.
449 ** AC_INIT no longer alters $@; regression introduced in 2.60.
451 ** AC_USE_SYSTEM_EXTENSIONS now defines _ALL_SOURCE for Interix platforms.
453 ** AS_HELP_STRING no longer underquotes its first argument; it also handles
454 the case where the first argument contains single-quoted commas.
455 For example, "AS_HELP_STRING([-a, [--arg[=foo]]], [bar])" produces:
456 " -a, --arg[=foo] bar"
457 Additionally, the macro now takes two additional arguments,
458 indent-column and wrap-column; these should not normally be needed,
459 but can be used to fine-tune how the output text is wrapped.
461 ** AC_PROG_INSTALL now requires an install program that can install multiple
462 files into a target directory.
464 ** The command 'autoconf -' now correctly processes a file from stdin.
466 ** 'autoreconf -m' now honors $MAKE.
468 ** For all of the directory arguments for 'configure', such as '--prefix'
469 or '--bindir', trailing slashes are stripped. As an example, if
470 tab completion in the user's shell appends trailing slashes, the
471 command './configure --prefix=/usr/' will still result in an
472 expanded libdir value of /usr/lib, not /usr//lib.
474 ** `configure --help=recursive' now works in read-only trees and from
475 unconfigured build trees.
477 ** If precious variables differ only in whitespace, then the cache consistency
478 check warns instead of fails, and reuses the old value.
480 ** AT_BANNER is now documented.
482 ** AT_SETUP now handles macro expansions properly when calculating line
485 ** Autotest now determines $srcdir correctly.
487 ** Testsuites built by autotest now accept a -C/--directory=DIR option
488 to adjust the working directory prior to creating files.
490 ** Autoconf now requires GNU M4 1.4.5 or later. Earlier versions of M4 have
491 a bug in macro tracing that interferes with the interaction between
492 Autoconf and Automake. GNU M4 1.4.11 or later is recommended. The
493 configure search for a working M4 is improved.
495 ** For portability with the eventual M4 2.0, macros should no longer use
496 anything larger than $9 to refer to arguments.
498 ** Documentation for m4sugar is improved.
500 - The following macros were previously available as undocumented
501 interfaces; the macros are now documented as stable interfaces.
503 __oline__ m4_assert m4_bmatch m4_bpatsubsts m4_car m4_case
504 m4_cdr m4_default m4_divert_once m4_divert_pop m4_divert_push
505 m4_divert_text m4_do m4_errprintn m4_fatal m4_flatten
506 m4_ifndef m4_ifset m4_ifval m4_ifvaln m4_location
507 m4_n m4_shiftn m4_strip m4_warn
509 - The following macros were previously available as undocumented
510 interfaces, but had bug fixes or semantic changes as part of this
511 release. Packages that relied on the undocumented behavior
512 should be analyzed to make sure they will still work with the
513 new documented behavior.
515 m4_cmp m4_list_cmp m4_join m4_map m4_map_sep m4_sign
516 m4_text_box m4_text_wrap m4_version_compare
518 - The m4_wrap macro used to have unspecified order, but now
519 guarantees FIFO order. m4_wrap_lifo was added to guarantee LIFO
522 - Packages using the undocumented m4sugar macro m4_PACKAGE_VERSION
523 should consider using the new AC_AUTOCONF_VERSION instead.
525 - m4sugar macros that are not documented in the manual are still
526 deemed experimental, and should not be used outside of Autoconf.
528 ** The m4sugar macros m4_append and m4_append_uniq, first documented in
529 2.60, have been fixed to treat both the string and the separator
530 arguments consistently with regards to quoting. Prior to this fix,
531 m4_append_uniq could mistakenly duplicate entries if the expansion
532 of the separator resulted in a different string (for example, if it
533 contained quotes, a comma, or a macro name). However, it means
534 that programs previously using
535 m4_append([name], [string], [[, ]])
536 are now using a four-character separator instead of the intended
537 comma and space. If you need portability to earlier versions of
538 Autoconf, you can insert the following snippet after AC_INIT but
539 before any other macro expansions, to enforce the new semantics:
540 m4_pushdef([m4_append], [m4_define([$1],
541 m4_ifdef([$1], [m4_defn([$1])[$3]])[$2])])
542 Additionally, m4_append_uniq now takes optional parameters that can
543 be used to take action depending on whether anything was appended,
544 and warns if a non-empty separator occurs within the string being
545 appended, since that can lead to duplicates.
547 ** The following m4sugar macros are new:
548 m4_append_uniq_w m4_apply m4_combine m4_cond m4_count
549 m4_dquote_elt m4_echo m4_expand m4_ignore m4_make_list m4_max
550 m4_min m4_newline m4_shift2 m4_shift3 m4_unquote m4_wrap_lifo
552 ** Warnings are now generated by default when an installer invokes
553 'configure' with an unknown --enable-* or --with-* option.
554 These warnings can be disabled with the new AC_DISABLE_OPTION_CHECKING
555 macro, or by invoking 'configure' with --disable-option-checking.
557 ** Existing obsolete macros
558 The documentation for the following macros is adjusted to make it
559 more clear that they have previously been marked obsolete, as their
560 functionality can be accomplished by other macros. We have no
561 current plans to remove them from Autoconf.
563 AC_ENABLE AC_STRUCT_ST_BLKSIZE AC_STRUCT_ST_RDEV AC_WITH
565 ** Newly obsolete macros
566 The following macros have been marked obsolete, as they only
567 perform a subset of AC_USE_SYSTEM_EXTENSIONS. We have no current
568 plans to remove them.
570 AC_AIX AC_GNU_SOURCE AC_ISC_POSIX AC_MINIX
572 ** AC_C_LONG_DOUBLE is obsolescent.
573 The documentation now says that AC_C_LONG_DOUBLE is obsolescent: it
574 tests for problems that are so old that it is no longer of
575 practical importance on current systems. New programs need not use
576 AC_C_LONG_DOUBLE. We have no current plans to remove it.
578 ** AC_DIAGNOSE, AC_WARNING, and AC_FATAL are obsolescent.
579 The documentation now favors the use of M4sugar macros m4_warn and
580 m4_fatal, since the naming makes it more obvious that the
581 diagnostics are associated with M4 expansion (ie. when running
582 `autoconf'), and offers less confusion with the AC_MSG_ERROR,
583 AC_MSG_FAILURE, and AC_MSG_WARN macros which manage diagnostics
584 when running `configure'. We have no current plans to remove these
588 * Major changes in Autoconf 2.61a (2006-12-11)
590 ** AC_FUNC_FSEEKO was broken in 2.61; it didn't make fseeko and ftello visible
591 on many platforms. This has been fixed.
593 ** AC_FUNC_SETVBUF_REVERSED is now obsolete. It is still defined for backward
594 compatibility but it does nothing. The macro was already
595 obsolescent, as the last systems to have the problem were those
596 based on SVR2, which became obsolete in 1987. The macro had bugs
597 on some modern systems and could no longer be maintained reliably
598 due to lack of ancient systems to test it on.
600 ** config.status now uses awk instead of sed for most substitutions, for speed.
602 - As a side effect multi-line values of substituted variables no
603 longer have a small limit in total size, though for portability
604 each line should not exceed the POSIX length limit for text lines.
606 - It is now documented that Makefile.in should not contain
607 overlapping variable occurrences, e.g., @VAR1@VAR2@.
608 Autoconf's behavior was always iffy in such cases, and the
609 awk implementation has changed the behavior.
611 ** Many uses of 'echo' have been rewritten so that Autoconf-generated
612 scripts have fewer problems with strings or file names containing
613 embedded special characters such as backslash or leading "-". This
614 was implemented by using `printf '%s\n' "$foo"' instead of `echo
615 "$foo"' when printf works. Due to the implementation technique
616 used, Autoconf-generated scripts now run considerably more slowly
617 on ancient implementations lacking printf. However, this should
618 not be a problem, since Autoconf-generated scripts in practice
619 invariably find a more-modern shell these days.
622 * Major changes in Autoconf 2.61 (2006-11-17)
624 ** New macros AC_C_FLEXIBLE_ARRAY_MEMBER, AC_C_VARARRAYS.
626 ** AC_ARG_ENABLE and AC_ARG_WITH now allow '.' in feature and package names.
629 * Major changes in Autoconf 2.60b (2006-10-22)
632 Autoconf-generated shell scripts no longer export BIN_SH, due to
633 configuration hassles with this. Installers who need BIN_SH in
634 their environment should set it before invoking 'configure' and
635 'make'. As far as we know, this affects only Unixware installations.
637 ** Obsolescent macros
638 The documentation now says that the following macros are obsolescent,
639 as they are superseded by Gnulib:
641 AC_FUNC_FNMATCH AC_FUNC_FNMATCH_GNU AC_FUNC_GETLOADVG AC_REPLACE_FNMATCH
643 New programs should use the Gnulib counterparts of these macros.
644 We have no current plans to remove them from Autoconf.
646 ** AC_COMPUTE_INT no longer caches or reports results.
648 ** AC_CHECK_DECL now also works with aggregate objects.
650 ** AC_USE_SYSTEM_EXTENSIONS now defines _TANDEM_SOURCE for NonStop platforms.
652 ** GNU M4 1.4.7 or later is now recommended.
655 New M4sugar macro, which is more secure than the POSIX M4 maketemp.
658 Now an alias for m4_mkstemp.
660 * Major changes in Autoconf 2.60a (2006-08-25)
662 ** GNU M4 1.4.6 or later is now recommended.
664 ** The check for C99 now tests for varargs macros, as documented.
665 It also tests that the preprocessor supports 64-bit integers.
667 ** Autoconf now uses constructs like "#ifdef HAVE_STDLIB_H" rather than
668 "#if HAVE_STDLIB_H", so that it now works with "gcc -Wundef -Werror".
670 ** The functionality of the undocumented _AC_COMPUTE_INT is now provided
671 by a public and documented macro, AC_COMPUTE_INT. The parameters to the
672 two macros are different, so autoupdate will not change the old private name
673 to the new one. _AC_COMPUTE_INT may be removed in a future release.
675 ** AC_TYPE_LONG_LONG_INT and AC_TYPE_UNSIGNED_LONG_LONG_INT now require
676 that long long types be at least 64 bits wide, as C99 and tradition
677 requires. Formerly, they accepted implementations of any width.
680 * Major changes in Autoconf 2.60
682 Released 2006-06-23, by Ralf Wildenhues.
684 ** Autoconf no longer depends on whether m4wrap is FIFO (as Posix requires)
685 or LIFO (as in GNU M4 1.4.x). GNU M4 2.0 is expected to conform to Posix
686 here, so m4wrap/m4_wrap users should no longer depend on LIFO behavior.
688 ** Provide a way to turn off warnings about the changed directory variables.
690 * Major changes in Autoconf 2.59d
692 Released 2006-06-05, by Ralf Wildenhues.
694 ** GNU make now recommended for VPATH builds
695 INSTALL now suggests VPATH builds (e.g., "sh ../srcdir/configure")
696 only if you use GNU make. In practice, other 'make' implementations
697 have too many subtle incompatibilities in their support for VPATH.
698 Many packages (including Autoconf itself) are portable to other
699 'make' implementations, but some packages are not, and recommending
700 GNU make keeps the installation instructions simpler.
702 ** Even more safety checks for the new Directory variables:
703 Warn about suspicious `${datarootdir}' found in config files output.
705 ** AC_TRY_COMMAND, AC_TRY_EVAL, ac_config_guess, ac_config_sub, ac_configure
706 These never-documented macros and variables have been marked with
707 comments saying that they may be removed in a future release,
708 because their use can lead to unintended code being executed.
709 If you need functionality that only these macros or variables
710 currently supply, please write bug-autoconf@gnu.org.
712 ** AC_SUBST, AC_DEFINE
713 Literal arguments to these are passed to m4_pattern_allow now.
716 Passing 'ac_cv_prog_cc_stdc=no' to 'configure' now sets ac_cv_prog_cc_c99
717 and ac_cv_prog_cc_c89 to 'no' as well, for backward compatibility with
718 obsolete K&R tests in the Automake test suite.
727 Now more robust with special characters in file names, or when
728 multiple processes create the same directory at the same time.
730 ** Obsolescent macros
731 The documentation now says that the following macros are obsolescent:
732 they test for problems that are so old that they are no longer of
733 practical importance on current systems.
735 AC_C_BACKSLASH_A AC_FUNC_MEMCMP AC_HEADER_DIRENT
736 AC_C_CONST AC_FUNC_SELECT_ARGTYPES AC_HEADER_STAT
737 AC_C_PROTOTYPES AC_FUNC_SETPGRP AC_HEADER_STDC
738 AC_C_STRINGIZE AC_FUNC_SETVBUF_REVERSED AC_HEADER_SYS_WAIT
739 AC_C_VOLATILE AC_FUNC_STAT AC_HEADER_TIME
740 AC_FUNC_CLOSEDIR_VOID AC_FUNC_STRFTIME AC_ISC_POSIX
741 AC_FUNC_GETPGRP AC_FUNC_UTIME_NULL AC_PROG_GCC_TRADITIONAL
742 AC_FUNC_LSTAT AC_FUNC_VPRINTF AC_STRUCT_TM
744 New programs need not use these macros. We have no current plans to
748 For compatibility with future Libtool 2.0, autoreconf will invoke
749 libtoolize with the option `--ltdl' now, if LT_CONFIG_LTDL_DIR is
752 * Major changes in Autoconf 2.59c
754 Released 2006-04-12, by Ralf Wildenhues.
756 ** The configure command now redirects standard input from /dev/null,
757 to help avoid problems with subsidiary commands that might mistakenly
758 read standard input. AS_ORIGINAL_STDIN_FD points to the original
759 standard input before this redirection, if you really want configure to
760 read from standard input.
762 ** Directory variables adjusted to recent changes in the GNU Coding Standards.
763 The following directory variables are new:
765 datarootdir read-only architecture-independent data root [PREFIX/share]
766 localedir locale-specific message catalogs [DATAROOTDIR/locale]
767 docdir documentation root [DATAROOTDIR/doc/PACKAGE]
768 htmldir html documentation [DOCDIR]
769 dvidir dvi documentation [DOCDIR]
770 pdfdir pdf documentation [DOCDIR]
771 psdir ps documentation [DOCDIR]
773 The following variables have new default values:
775 datadir read-only architecture-independent data [DATAROOTDIR]
776 infodir info documentation [DATAROOTDIR/info]
777 mandir man documentation [DATAROOTDIR/man]
779 This means that if you use any of `@datadir@', `@infodir@', or
780 `@mandir@' in a file, you will have to ensure `${datarootdir}' is
781 defined in this file. As a temporary measure, if any of those are
782 found but no mention of `datarootdir', the substitutions will be
783 replaced with values that do not contain `${datarootdir}', and a
784 warning will be issued.
786 ** @top_builddir@ is now a dir name: it is always nonempty and doesn't have
787 a trailing slash. Similar change will be made to ac_top_builddir in a
788 future release; the old style value, which matches (../)*, is (and will
789 continue to be) available as ac_top_build_prefix.
792 New macro to check for support of 'typeof' syntax a la GNU C.
794 ** AC_CHECK_DECLS_ONCE, AC_CHECK_FUNCS_ONCE, AC_CHECK_HEADERS_ONCE
795 New "once-only" variants of commonly-used macros, to make 'configure'
796 smaller and faster in common cases.
799 New macro to check for strtold with C99 semantics.
802 New macro that lets builder disable assertions at 'configure'-time.
805 Now checks for X11/Xlib.h and XrmInitialize (X proper) rather than
806 X11/Intrinsic.h and XtMalloc (Xt).
808 ** AC_PRESERVE_HELP_ORDER
809 New macro that causes `configure' to display help strings for AC_ARG_ENABLE
810 and AC_ARG_WITH arguments in one region, in the order defined. The default
811 behavior is to group options of each classes separately.
813 ** AC_PROG_CC, AC_PROG_CXX
814 No longer automatically arrange to declare the 'exit' function of C,
815 when a C++ compiler is used. Standard Autoconf macros no longer use
816 'exit', so this is no longer an issue for them. If you use C++, and
817 want to call 'exit', you'll have to arrange for its declaration
818 yourself. But we now suggest you return from 'main' instead.
820 ** AC_PROG_CC_C89, AC_PROG_CC_C99
821 New macros for ISO C99 support. AC_PROG_CC_C89 and AC_PROG_CC_C99
822 check for ANSI C89 and ISO C99 support respectively.
825 Has been unobsoleted, and will check if the compiler supports ISO
826 C99, falling back to ANSI C89 if not. ac_cv_prog_cc_stdc is
827 retained for backwards compatibility, assuming the value of
828 ac_cv_prog_cc_c99 or ac_cv_prog_cc_c89 (whichever is valid, in
831 ** AC_STRUCT_DIRENT_D_INO, AC_STRUCT_DIRENT_D_TYPE
832 New macros for checking commonly-used members of struct dirent.
835 The substituted value can now contain newlines.
838 The substitution now occurs only when @variable@ is on a line by itself,
839 optionally surrounded by spaces and tabs. The whole line is replaced.
841 ** AC_TYPE_LONG_DOUBLE, AC_TYPE_LONG_DOUBLE_WIDER
842 New macros to check for long double, and whether it is wider than double.
843 The old macro AC_C_TYPE_LONG_DOUBLE has been marked as obsolete;
844 applications should switch to the new macro.
846 ** AC_TYPE_INT8_T, AC_TYPE_INT16_T, AC_TYPE_INT32_T, AC_TYPE_INT64_T,
847 AC_TYPE_INTMAX_T, AC_TYPE_INTPTR_T, AC_TYPE_LONG_LONG_INT, AC_TYPE_SSIZE_T,
848 AC_TYPE_UINT8_T, AC_TYPE_UINT16_T, AC_TYPE_UINT32_T, AC_TYPE_UINT64_T,
849 AC_TYPE_UINTMAX_T, AC_TYPE_UINTPTR_T, AC_TYPE_UNSIGNED_LONG_LONG_INT
850 New macros to check for C99 and POSIX types.
852 ** AC_USE_SYSTEM_EXTENSIONS
853 New macro to enable extensions to Posix.
856 New macro which is defined to the name of the first declared config header
857 or undefined if no config headers have been declared yet.
860 The macro correctly handles quadrigraphs now.
862 ** AS_BOURNE_COMPATIBLE, AS_SHELL_SANITIZE, AS_CASE
863 These macros are new or published now.
866 New macro for copyright notices in testsuite files.
868 ** ALLOCA, LIBOBJS, LTLIBOBJS
869 Object names added to these variables are now prefixed with `${LIBOBJDIR}',
870 as in `${LIBOBJDIR}alloca.o'. LIBOBJDIR is meant to be defined from
871 `Makefile.in' in case the object files lie in a different directory.
872 The LIBOBJDIR feature is experimental.
875 Supports --no-recursive now.
877 ** New macros to support Erlang/OTP.
878 New macros for configuring paths to Erlang tools and libraries:
879 AC_ERLANG_PATH_ERLC, AC_ERLANG_NEED_ERLC, AC_ERLANG_PATH_ERL,
880 AC_ERLANG_NEED_ERL, AC_ERLANG_CHECK_LIB, AC_ERLANG_SUBST_ROOT_DIR,
881 AC_ERLANG_SUBST_LIB_DIR.
883 New macros for configuring installation of Erlang libraries:
884 AC_ERLANG_SUBST_INSTALL_LIB_DIR, AC_ERLANG_SUBST_INSTALL_LIB_SUBDIR.
886 ** The manual now mentions Gnulib more prominently.
888 ** New macros to support Objective C.
889 AC_PROG_OBJC, AC_PROG_OBJCPP.
891 * Major changes in Autoconf 2.59b
893 Released 2004-08-20, by Paul Eggert.
896 New macro that computes the default alignment of a type.
898 ** AC_CHECK_TOOL, AC_PATH_TOOL, AC_CHECK_TOOLS
899 When cross-compiling, these macros will give a warning if the tool
900 is not prefixed. In the future, unprefixed cross tools will not
901 be detected; please consult the info documentation for information
902 about the reason of this change.
904 ** AC_CHECK_TARGET_TOOL, AC_PATH_TARGET_TOOL, AC_CHECK_TARGET_TOOLS
905 New macros that detect programs whose name is prefixed with the
906 target type, if the build type and target type are different.
908 ** AC_REQUIRE_AUX_FILE
909 New trace macro that declares expected auxiliary files.
912 New macro that tests for a grep program that accepts as a long a line
915 ** AC_PROG_EGREP, AC_PROG_FGREP
916 These macros now require AC_PROG_GREP, and try EGREP="$GREP -E" and
917 FGREP="$GREP -F" respectively if possible, or else run a path search for
918 a program that accepts as long a line as possible.
921 New macro that tests for a sed program that truncates as few characters
924 * Major changes in Autoconf 2.59
926 Released 2003-11-04, by Akim Demaille
928 ** ac_abs_builddir etc.
929 Absolute file names were actually relative in 2.58.
931 * Major changes in Autoconf 2.58
933 Released 2003-11-04, by Akim Demaille
936 core.* files are no longer removed, as they may be valid user files.
938 ** autoreconf and auxiliary directory
939 Autoreconf creates the auxiliary directory if needed. This is
940 especially useful for initial "bootstrapping" of fresh CVS checkouts.
942 ** AC_CONFIG_MACRO_DIR
943 Use this macro to declare the directory for local M4 macros for aclocal.
946 No longer includes twice the same file in LIBOBJS if invoked
949 ** AC_CONFIG_COMMANDS
950 The directory for its first argument is automatically created. For
953 AC_CONFIG_COMMANDS([src/modules.hh], [...])
955 $top_builddir/src/ is created if needed.
957 ** Autotest and local.at
958 The optional file local.at is always included in Autotest test suites.
961 The warnings are always issued, including with cached runs.
962 This became a significant problem since aclocal and automake can
963 run autoconf behind the scene.
965 ** autoheader warnings
966 The warnings of autoheader can be turned off, using --warning.
967 For instance, -Wno-obsolete disables the complaints about acconfig.h
968 and other deprecated constructs.
971 AC_C_RESTRICT, AC_INCLUDES_DEFAULT, AC_LANG_ASSERT, AC_LANG_WERROR,
974 ** AC_DECL_SYS_SIGLIST
978 Now checks that mktime is the inverse of localtime.
980 ** Improve DJGPP portability
981 The Autoconf tools and configure behave better under DJGPP.
983 ** Present But Cannot Be Compiled
984 New FAQ section dedicated to the mystic
986 configure: WARNING: pi.h: present but cannot be compiled
987 configure: WARNING: pi.h: check for missing prerequisite headers?
988 configure: WARNING: pi.h: proceeding with the preprocessor's result
991 ** Concurrent executions of autom4te
992 autom4te now locks its internal files, which enables concurrent
993 executions of autom4te, likely to happen if automake, autoconf,
994 autoheader etc. are run simultaneously.
997 Use of Libtool 1.5 and higher is encouraged. Compatibility with
998 Libtool pre-1.4 is not checked.
1001 Testsuites no longer rerun failed tests in verbose mode; instead,
1002 failures are logged while the test is run.
1004 In addition, expected failures can be marked as such.
1006 * Major changes in Autoconf 2.57
1008 Released 2002-12-03 by Paul Eggert.
1010 Bug fixes for problems with AIX linker, with freestanding C compilers,
1011 with GNU M4 limitations, and with obsolete copies of GNU documents.
1013 The Free Documentation License has been upgraded from 1.1 to 1.2.
1015 * Major changes in Autoconf 2.56
1017 Released 2002-11-15 by Akim Demaille.
1019 One packaging problem fixed (config/install-sh was not executable).
1021 * Major changes in Autoconf 2.55
1023 Released 2002-11-14 by Akim Demaille.
1027 Have your configure.ac checked by autoscan ("autoscan").
1028 Try the warning options ("autoreconf -fv -Wall").
1032 - AC_CHECK_HEADER, AC_CHECK_HEADERS
1033 More information on proper use.
1035 - Writing Test Programs
1037 This sections explains how to write good test sources to use with
1038 AC_COMPILE_IFELSE etc. It documents AC_LANG_PROGRAM and so forth.
1040 - AC_FOO_IFELSE vs. AC_TRY_FOO
1042 Explains why Autoconf moves from AC_TRY_COMPILE etc. to
1043 AC_COMPILE_IFELSE and AC_LANG_PROGRAM etc.
1047 - Is more robust to different Gettext installations.
1049 - Produces messages (when --verbose) to be understood by Emacs'
1052 - Supports -W/--warnings.
1055 Once the GNU Build System reinstalled, run `./config.status
1056 --recheck && ./config.status && make' if possible.
1060 - Supports --cache, and --no-cache.
1062 - ~/.autom4te.cfg makes it possible to disable the caching mechanism
1063 (autom4te.cache). See `Customizing autom4te' in the documentation.
1070 Support for the obsoleted options -m, --macrodir, -l, --localdir is
1071 dropped in favor of the safer --include/--prepend-include scheme.
1076 AC_COMPILER_IFELSE, AC_FUNC_MBRTOWC, AC_HEADER_STDBOOL,
1077 AC_LANG_CONFTEST, AC_LANG_SOURCE, AC_LANG_PROGRAM, AC_LANG_CALL,
1078 AC_LANG_FUNC_TRY_LINK, AC_MSG_FAILURE, AC_PREPROC_IFELSE.
1081 Obsoleted macros are kept for Autoconf backward compatibility, but
1082 should be avoided in configure.ac. Running autoupdate is advised.
1083 AC_DECL_SYS_SIGLIST.
1085 - AC_DEFINE/AC_DEFINE_UNQUOTED
1087 We have to stop using the old compatibility scheme --that tried to
1088 avoid useless backslashes-- because Libtool 1.4.3 contains a
1090 AC_DEFINE([error_t], [int],
1091 [Define to a type to use for \`error_t' if it is not
1092 otherwise available.])
1094 We have to quote the single quotes and backslashes with \. The old
1095 compatibility scheme saw that ` was backslashed, and therefore did
1096 not quote the single quote... Failure. Hence, Autoconf 2.54 is not
1097 compatible with Libtool. Autoconf 2.55 is, but in some cases might
1098 produce more \ than wanted.
1100 Please, note that in the future the same problem will happen with
1101 AC_MSG_*: use `autoreconf -f -Wall'.
1105 - Portability of the Autoconf package to Solaris.
1107 - Spurious warnings caused by config.status.
1108 This bug is benign, but painful: on some systems (typically
1109 FreeBSD), warnings such as:
1111 config.status: creating Makefile
1112 mv: Makefile: set owner/group (was: 1357/0): Operation not permitted
1114 could be issued. This is fixed.
1117 Simultaneous executions of config.status are possible again.
1119 - Precious variables accumulation
1121 config.status could stack several copies of the precious variables
1125 ** Plans for later versions
1127 - ./configure <host>
1129 The compatibility hooks with the old scheme will be completely
1130 removed. Please, advice/use `--build', `--host', and `--target'
1133 - AC_CHECK_HEADER, AC_CHECK_HEADERS
1135 The tests will be stricter, please make sure your invocations are
1140 Shell functions will gradually be introduced, probably starting with
1141 Autotest. If you know machines which are in use that you suspect
1142 *not* to support shell functions, please run the test suite of
1143 Autoconf 2.55 on it, and report the results to
1144 bug-autoconf@gnu.org.
1148 Special characters in AC_MSG_* need not be quoted. Currently,
1149 Autoconf has heuristics to decide when a string is escaped, or has
1150 to be escaped. This scheme is fragile, and will be removed; the
1151 only risk is uglified messages. Please, run `autoreconf -f -Wall'
1152 to find occurrences that will be affected.
1154 * Major changes in Autoconf 2.54
1156 Released 2002-09-13 by Akim Demaille.
1160 - autoreconf no longer changes the version of the gettext/po/intl
1161 support files. It now adds the files the correspond to the
1162 AM_GNU_GETTEXT_VERSION declared in configure.ac.
1164 Warning: It now relies on the 'autopoint' program, which is part
1165 of GNU gettext 0.11.4 and newer.
1167 Please note that you need to have a GNU gettext version that
1168 corresponds at least to the AM_GNU_GETTEXT_VERSION declared
1169 in configure.ac. You can upgrade to newer GNU gettext versions,
1170 though, without needing to change configure.ac.
1172 - The -I DIR or --include=DIR option now appends DIR to the include path
1173 instead of prepending; this is for consistency with other GNU tools.
1174 The new -B DIR or --prepend-include=DIR option has the old behavior.
1179 Now handles all the gory details about LIBOBJS and LTLIBOBJS.
1180 Please, remove lines such as
1182 # This is necessary so that .o files in LIBOBJS are also
1183 # built via the ANSI2KNR-filtering rules.
1184 LIBOBJS=`echo $LIBOBJS|sed 's/\.o /\$U.o /g;s/\.o$/\$U.o/'`
1186 and read the `AC_LIBOBJ vs LIBOBJS' section. Do not define U in
1187 your Makefiles either.
1189 - AC_CONFIG_LINKS now makes copies if it can't make links.
1191 - AC_FUNC_FNMATCH now tests only for POSIX compatibility, reverting to
1192 Autoconf 2.13 behavior. The new macro AC_FUNC_FNMATCH_GNU also
1193 tests for GNU extensions to fnmatch, and replaces fnmatch if needed.
1195 - AC_FUNC_SETVBUF_REVERSED no longer fails when cross-compiling.
1197 - AC_PROG_CC_STDC is integrated into AC_PROG_CC.
1199 - AC_PROG_F77 default search no longer includes cf77 and cfg77.
1203 AC_C_BACKSLASH_A, AC_CONFIG_LIBOBJ_DIR, AC_GNU_SOURCE,
1204 AC_PROG_EGREP, AC_PROG_FGREP, AC_REPLACE_FNMATCH,
1205 AC_FUNC_FNMATCH_GNU, AC_FUNC_REALLOC, AC_TYPE_MBSTATE_T.
1207 - AC_FUNC_GETLOADAVG
1208 looks for getloadavg.c in the CONFIG_LIBOBJ_DIR.
1211 Now defines HAVE_MALLOC to 0 if `malloc' does not work, and asks
1212 for an AC_LIBOBJ replacement.
1216 - Spurious complaints from `m4_bmatch' about invalid regular
1217 expressions are suppressed.
1219 - Empty top_builddirs are properly handled.
1221 - AC_CHECK_MEMBER works correctly when the member is an aggregate.
1224 Now colon in the optional path arguments are properly handled.
1226 ** Improved portability
1228 - Both Autoconf the package, and the scripts it produces, should run
1229 more reliably with Zsh. Bear in mind it is the default Bourne shell
1232 - Autoconf and the scripts it produces no longer assume the existence of
1233 the obsolescent commands egrep and fgrep.
1237 - Limitations of Make
1241 The GNATS base moved to
1242 http://bugs.gnu.org/cgi-bin/gnatsweb.pl?database=autoconf
1243 (It is no longer available, though.)
1248 Now contains the list of ouput variables and files (AC_SUBST,
1251 * Major changes in Autoconf 2.53
1253 Released 2002-03-08 by Akim Demaille.
1257 Perl 5.005_03 or later is required: autom4te is written in Perl and is
1258 needed by autoconf. autoheader, autoreconf, ifnames, and autoscan are
1264 Argument requirements, output variables, defined macros.
1265 - M4sugar, M4sh, Autotest
1267 - Double quoting macros
1268 AC_TRY_CPP, AC_TRY_COMPILE, AC_TRY_LINK and AC_TRY_RUN.
1270 The Autoconf manual is now distributed under the terms of the GNU FDL.
1271 - Section `Hosts and Cross-Compilation'
1272 Explains the rationale for the 2.5x changes in the cross-compilation
1273 chain, and in the relationships between build, host, and target
1275 Emphasizes that `cross-compilation' == `--host is given'.
1276 If you are working on compilers etc., be sure to read this section.
1277 - Section `AC_LIBOBJ vs. LIBOBJS'
1278 Explains why assigning LIBOBJS directly is now an error.
1279 Details how to update the code.
1284 Now used instead of hard coded line numbers.
1285 This eases the comparison of `configure's, and diminishes the
1286 pressure over control version archives.
1287 Automatic replacement for shells that don't support this feature.
1288 - New output variables
1289 @builddir@, @top_builddir@, @abs_srcdir@, @abs_top_srcdir@, @abs_builddir@,
1294 Autoconf and Autotest modes are provided.
1299 New, used by the Autoconf suite to cache and speed up most processing.
1301 Supported by autom4te, autoconf and autoheader.
1303 Replaces --autoconf-dir and --localdir in autoconf, autoheader,
1304 autoupdate, and autoreconf.
1306 No longer passes --cygnus, --foreign, --gnits, --gnu, --include-deps:
1307 automake options are to be given via AUTOMAKE_OPTIONS.
1309 Runs gettextize and libtoolize when appropriate.
1311 --m4dir is no longer supported.
1313 Now runs only in the specified directories, defaulting to `.',
1314 but understands AC_CONFIG_SUBDIRS for dependent directories.
1315 Before, it used to run on all the `configure.ac' found in the
1317 Independent packages are properly updated.
1321 - The top level $prefix is propagated to the AC_CONFIG_SUBDIRS configures.
1323 Under the user pressure, $? is finally available. Probably a mistake.
1324 - AC_F77_LIBRARY_LDFLAGS now supports the HP/UX f90 compiler.
1325 - Precious variables accumulation
1326 config.status could stack several copies of the precious variables
1328 - AC_PATH_PROG and family.
1329 Works properly when given a literal path.
1331 Somewhere since 2.13, the result had been reversed.
1335 - AC_C_BIGENDIAN supports the cross-compiling case.
1336 - AC_C_BIGENDIAN accepts ACTION-IF-TRUE, ACTION-IF-FALSE, and
1337 ACTION-IF-UNKNOWN arguments. All are facultative, and the default
1338 for ACTION-IF-TRUE is to define WORDS_BIGENDIAN like AC_C_BIGENDIAN
1340 - AC_C_LONG_DOUBLE now succeeds only if `long double' has more range or
1341 precision than `double'.
1346 It now defines the preprocessor symbols PACKAGE_NAME,
1347 PACKAGE_TARNAME, PACKAGE_VERSION, PACKAGE_STRING, and
1351 Admits a fourth optional parameter: the tar name.
1353 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS.
1354 Provide the user with srcdir, ac_srcdir, ac_top_srcdir, ac_builddir,
1355 ac_top_builddir, ac_abs_srcdir, ac_abs_top_srcdir, ac_abs_builddir,
1356 ac_abs_top_builddir.
1358 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS and AC_OUTPUT.
1359 Are much less expensive when using long lists of files.
1362 Works with shell variables, and non alphanumeric names.
1366 - AC_FUNC_STRERROR_R now sets STRERROR_R_CHAR_P, not HAVE_WORKING_STRERROR_R,
1367 because POSIX 1003.1-200x draft 7 says strerror_r returns int, not char *.
1369 - AC_FUNC_STRTOD substitutes POW_LIB.
1374 * Major changes in Autoconf 2.52
1376 Released 2001-07-18 by Akim Demaille.
1381 This feature was present in autoconf 2.50 but was not documented.
1382 For example, `@<:@' is translated to `[' just before output. This
1383 is useful when writing strings that contain unbalanced quotes, or
1384 other hard-to-quote constructs.
1385 - m4_pattern_forbid, m4_pattern_allow
1386 - Tips for upgrading from 2.13.
1387 - Using autoscan to maintain a configure.ac.
1390 - Now include stdint.h.
1391 - sys/types.h and sys/stat.h are guarded.
1392 - strings.h is included if available, and not conflicting with string.h.
1395 - The test suite is more robust and presents less false failures.
1396 - Invocation of GNU M4 now robust to POSIXLY_CORRECT.
1397 - configure accepts --prefix='' again.
1398 - AC_CHECK_LIB works properly when its first argument is not a
1400 - HAVE_INTTYPES_H is defined only if not conflicting with sys/types.h.
1401 - build_, host_, and target_alias are AC_SUBST as in 2.13.
1402 - AC_ARG_VAR properly propagates precious variables inherited from the
1403 environment to ./config.status.
1404 - Using --program-suffix/--program-prefix is portable.
1405 - Failures to detect the default compiler's output extension are less
1407 - `config.status foo' works properly when `foo' depends on variables
1408 set in an AC_CONFIG_THING INIT-CMD.
1409 - autoheader is more robust to broken input.
1410 - Fixed Fortran name-mangling and link tests on a number of systems,
1411 e.g. NetBSD; see AC_F77_DUMMY_MAIN, below.
1414 - AC_CHECK_HEADER and AC_CHECK_HEADERS support a fourth argument to
1415 specify pre-includes. In this case, the headers are compiled with
1416 cc, not merely preprocessed by cpp. Therefore it is the _usability_
1417 of a header which is checked for, not just its availability.
1418 - AC_ARG_VAR refuses to run configure when precious variables have
1420 - Versions of compilers are dumped in the logs.
1421 - AC_CHECK_TYPE recognizes use of `foo_t' as a replacement type.
1424 - AC_PATH_XTRA only adds -ldnet to $LIBS if it's needed to link.
1425 - AC_FUNC_WAIT3 and AC_SYS_RESTARTABLE_SYSCALLS are obsoleted.
1426 - AM_FUNC_ERROR_AT_LINE, AM_FUNC_FNMATCH, AM_FUNC_MKTIME,
1427 AM_FUNC_OBSTACK, and AM_FUNC_STRTOD are now activated.
1428 Be sure to read `Upgrading from Version 2.13' to understand why
1429 running `autoupdate' is needed.
1430 - AC_F77_DUMMY_MAIN, AC_F77_MAIN: new macros to detect whether
1431 a main-like routine is required/possible when linking C/C++ with
1432 Fortran. Users of e.g. AC_F77_WRAPPERS should be aware of these.
1433 - AC_FUNC_GETPGRG behaves better when cross-compiling.
1435 * Major changes in Autoconf 2.51
1436 There was no release of Autoconf 2.51 since some packagers had used
1437 this version number without permission to ship intermediary versions
1438 of 2.50. The version was skipped to avoid confusion.
1440 * Major changes in Autoconf 2.50
1442 Released 2001-05-21 by Akim Demaille.
1444 ** Lots of bug fixes
1445 There have been far too many to enumerate them here. Check out
1446 ChangeLog if you really want to know more.
1448 ** Improved documentation
1449 In particular, portability issues are better covered.
1452 All the standard GNU Makefile targets are supported. The layout has
1453 changed: m4/ holds the M4 extensions Autoconf needs for its
1454 configuration, doc/ contains the documentation, and tests/ contains
1457 ** Man pages are provided
1458 For autoconf, autoreconf, autoupdate, autoheader, autoscan, ifnames,
1459 config.guess, config.sub.
1463 Provides a safe and powerful means to trace the macro uses. This
1464 provide the parsing layer for tools which need to `study'
1468 Specify what category of warnings should be enabled.
1470 - When recursing into subdirectories, try for configure.gnu before
1471 configure to adapt for packages not using autoconf on case-insensitive
1475 More errors are now caught (circular AC_REQUIRE dependencies,
1476 AC_DEFINE in the action part of an AC_CACHE_CHECK, too many pops
1477 etc.). In addition, their location and call stack are given.
1480 autoupdate is much more powerful, and is able to provide the glue code
1481 which might be needed to move from an old macro to its newer
1484 You are strongly encouraged to use it to modernize both your
1485 `configure.in' and your .m4 extension files.
1488 The internal machinery of autoheader has completely changed. As a
1489 result, using `acconfig.h' should be considered to be obsoleted, and
1490 you are encouraged to get rid of it using the AH macros.
1495 ** Fortran 77 compilers
1496 Globally, the support for Fortran 77 is considerably improved.
1498 Support for automatically determining a Fortran 77 compiler's
1499 name-mangling scheme. New CPP macros F77_FUNC and F77_FUNC_ are
1500 provided to wrap C/C++ identifiers, thus making it easier and more
1501 transparent for C/C++ to call Fortran 77 routines, and Fortran 77 to
1502 call C/C++ routines. See the Texinfo documentation for details.
1505 The test suite no longer uses DejaGNU. It should be easy to submit
1506 test cases in this new framework.
1509 - --help, --help=long, -hl
1510 no longer dumps useless items.
1512 lists only specific options.
1513 - --help=recursive, -hr
1514 displays the help of all the embedded packages.
1515 - Remembers environment variables when reconfiguring.
1516 The previous scheme to set envvar before running configure was
1518 what prevented configure from remembering the environment in which
1519 it was run, therefore --recheck was run in an inconsistent
1520 environment. Now, one should run
1522 and then --recheck will work properly. Variables declared with
1523 AC_ARG_VAR are also preserved.
1525 $build defaults to `config.guess`, $host to $build, and then $target
1527 Cross-compilation is a global status of the package, it no longer
1528 depends upon the current language.
1529 Cross compilation is enabled iff the user specified `--host'.
1530 `configure' now fails if it can't run the executables it compiles,
1531 unless cross-compilation is enabled.
1533 The cache file is disabled by default. The new options
1534 `--config-cache', `-C' set the cache to `config.cache'.
1538 Much faster on most architectures.
1539 - concurrent executions
1540 It is safe to use `make -j' with config.status.
1541 - human interface improved
1542 It is possible to invoke
1543 ./config.status foobar
1544 instead of the former form (still valid)
1545 CONFIG_COMMANDS= CONFIG_HEADERS= CONFIG_LINKS= \
1546 CONFIG_FILES=foobar:foo.in:bar.in \
1548 The same holds for configuration headers and links.
1549 You can instantiate unknown files and headers:
1550 ./config.status --header foo.h:foo.h.in --file bar:baz
1551 - has a useful --help
1552 - accepts special file name "-" for stdin/stdout
1557 Specify additional copyright information.
1560 Now expects the identity of the package as argument.
1564 Most macros, if not all, now strictly follow the `one quotation
1565 level' rule. This results in a more predictable expansion.
1568 A sly bug in the AC_REQUIRE machinery, which could produce incorrect
1569 configure scripts, was fixed by Axel Thimm.
1573 Document and ask for the registration of an envvar.
1576 Specifies the file which `configure' should look for when trying to
1577 find the source tree (used to be handled by AC_INIT).
1579 - AC_CONFIG_COMMANDS
1580 To add new actions to config.status. Should be used instead of
1584 Replaces AC_LINK_FILES.
1586 - AC_CONFIG_HEADERS, AC_CONFIG_COMMANDS, AC_CONFIG_SUBDIRS,
1587 AC_CONFIG_LINKS, and AC_CONFIG_FILES
1588 They now obey sh: you should no longer use shell variables as
1589 argument. Instead of
1591 test "$package_foo_enabled" = yes && $my_subdirs="$my_subdirs foo"
1592 AC_CONFIG_SUBDIRS($my_subdirs)
1596 if test "$package_foo_enabled" = yes; then
1597 AC_CONFIG_SUBDIRS(foo)
1601 To format an Autoconf macro's help string so that it looks pretty
1602 when the user executes `configure --help'.
1605 ** Generic Test Macros
1607 The interface of the AC_CHECK families of macros (decl, header,
1608 type, member, func) is now uniform. They support the same set of
1611 - AC_CHECK_DECL, AC_CHECK_DECLS
1612 To check whether a symbol is declared.
1614 - AC_CHECK_SIZEOF, AC_C_CHAR_UNSIGNED.
1615 No longer need a cross-compilation default.
1618 The test it performs is much more robust than previously, and makes
1619 it possible to test builtin types in addition to typedefs.
1620 It is now schizophrenic:
1621 - AC_CHECK_TYPE(TYPE, REPLACEMENT)
1622 remains for backward compatibility, but its use is discouraged.
1623 - AC_CHECK_TYPE(TYPE, IF-FOUND, IF-NOT-FOUND, INCLUDES)
1624 behaves exactly like the other AC_CHECK macros.
1627 Checks whether given types are supported by the system.
1629 - AC_CHECK_MEMBER, AC_CHECK_MEMBERS
1630 Check for given members in aggregates (e.g., pw_gecos in struct
1634 Checks if the compiler supports ISO C, included when needs special
1638 Checking whether the preprocessor indicates missing includes by the
1639 error code. stderr is checked by AC_TRY_CPP only as a fallback.
1642 Takes a language as argument and replaces AC_LANG_C,
1643 AC_LANG_CPLUSPLUS and AC_LANG_FORTRAN77.
1645 - AC_LANG_PUSH, AC_LANG_POP
1646 Are preferred to AC_LANG_SAVE, AC_LANG_RESTORE.
1649 - AC_FUNC_CHOWN, AC_FUNC_MALLOC, AC_FUNC_STRERROR_R,
1650 AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK, AC_FUNC_STAT, AC_FUNC_LSTAT,
1651 AC_FUNC_ERROR_AT_LINE, AC_FUNC_OBSTACK, AC_FUNC_STRTOD, AC_FUNC_FSEEKO.
1655 Sets GETGROUPS_LIBS.
1657 - AC_FUNC_GETLOADAVG
1658 Defines `HAVE_STRUCT_NLIST_N_UN_N_NAME' instead of `NLIST_NAME_UNION'.
1661 Now integrates `AC_DECL_YYTEXT' which is obsoleted.
1664 Arrange for large-file support.
1666 - AC_EXEEXT, AC_OBJEXT
1667 You are no longer expected to use them: their computation is
1668 performed by default.
1670 ** C++ compatibility
1671 Every macro has been revisited in order to support at best CC=c++.
1673 Major changes in Autoconf 2.14:
1674 There was no release of GNU Autoconf 2.14.
1676 Major changes in Autoconf 2.13:
1678 Released 1999-05-01 by Ben Elliston.
1680 * Support for building on Win32 systems where the only available C or
1681 C++ compiler is the Microsoft Visual C++ command line compiler
1682 (`cl'). Additional support for building on Win32 systems which are
1683 using the Cygwin or Mingw32 environments.
1684 * Support for alternative object file and executable file extensions.
1685 On Win32, for example, these are .obj and .exe. These are discovered
1686 using AC_OBJEXT and AC_EXEEXT, which substitute @OBJEXT@ and
1687 @EXEEXT@ in the output, respectively.
1688 * New macros: AC_CACHE_LOAD, AC_CACHE_SAVE, AC_FUNC_SELECT_ARGTYPES,
1689 AC_VALIDATE_CACHED_SYSTEM_TUPLE, AC_SEARCH_LIBS, AC_TRY_LINK_FUNC,
1690 AC_C_STRINGIZE, AC_CHECK_FILE(S), AC_PROG_F77 (and friends).
1691 * AC_DEFINE now has an optional third argument for a description to be
1692 placed in the config header input file (e.g. config.h.in).
1693 * The C++ code fragment compiled for the C++ compiler test had to be
1694 improved to include an explicit return type for main(). This was
1695 causing failures on systems using recent versions of the EGCS C++
1697 * Fixed an important bug in AC_CHECK_TYPE that would cause a configure
1698 script to report that `sometype_t' was present when only `type_t'
1700 * Merge of the FSF version of config.guess and config.sub to modernize
1701 these scripts. Add support for a few new hosts in config.guess.
1702 Incorporate latest versions of install-sh, mkinstalldirs and
1703 texinfo.tex from the FSF.
1704 * autoreconf is capable of running automake if necessary (and
1706 * Support for Fortran 77. See the Texinfo documentation for details.
1707 * Bug fixes and workarounds for quirky bugs in vendor utilities.
1709 Major changes in Autoconf 2.12:
1711 Released 1996-11-26 by David J. MacKenzie
1713 * AC_OUTPUT and AC_CONFIG_HEADER can create output files by
1714 concatenating multiple input files separated by colons, like so:
1715 AC_CONFIG_HEADER(config.h:conf.pre:config.h.in:conf.post)
1716 AC_OUTPUT(Makefile:Makefile.in:Makefile.rules)
1717 The arguments may be shell variables, to compute the lists on the fly.
1718 * AC_LINK_FILES and AC_CONFIG_SUBDIRS may be called multiple times.
1719 * New macro AC_OUTPUT_COMMANDS adds more commands to run in config.status.
1722 Major changes in Autoconf 2.11:
1724 Released November 18th, 1996, by David J. MacKenzie
1726 * AC_PROG_CC and AC_PROG_CXX check whether the compiler works.
1727 They also default CFLAGS/CXXFLAGS to "-g -O2" for gcc, instead of "-g -O".
1728 * AC_REPLACE_FUNCS defines HAVE_foo if the system has the function `foo'.
1729 * AC_CONFIG_HEADER expands shell variables in its argument.
1730 * New macros: AC_FUNC_FNMATCH, AC_FUNC_SETPGRP.
1731 * The "checking..." messages and the source code for test programs that
1732 fail are saved in config.log.
1733 * Another workaround has been added for seds with small command length limits.
1734 * config.sub and config.guess recognize more system types.
1737 Major changes in Autoconf 2.10:
1739 Released May 7th, 1996, by Roland McGrath
1742 * The cache variable names used by `AC_CHECK_LIB(LIB, FUNC, ...)' has
1743 changed: now $ac_cv_lib_LIB_FUNC, previously $ac_cv_lib_LIB.
1745 Major changes in Autoconf 2.9:
1747 Released March 16th, 1996, by Roland McGrath
1751 Major changes in Autoconf 2.8:
1753 Released March 8th, 1996, by Roland McGrath
1757 Major changes in Autoconf 2.7:
1759 Released November 22nd, 1995, by David J. MacKenzie
1763 Major changes in Autoconf 2.6:
1765 Released November 20th, 1995, by David J. MacKenzie
1769 Major changes in Autoconf 2.5:
1771 Released November 17th, 1995, by Roland McGrath
1773 * New configure options --bindir, --libdir, --datadir, etc., with
1774 corresponding output variables.
1775 * New macro: AC_CACHE_CHECK, to make using the cache easier.
1776 * config.log contains the command being run as well as any output from it.
1777 * AC_CHECK_LIB can check for libraries with "." or "/" or "+" in their name.
1778 * AC_PROG_INSTALL doesn't cache a name for install-sh, for sharing caches.
1779 * AC_CHECK_PROG, AC_PATH_PROG, AC_CHECK_PROGS, AC_PATH_PROGS, and
1780 AC_CHECK_TOOL can search a path other than $PATH.
1781 * AC_CHECK_SIZEOF takes an optional size to use when cross-compiling.
1783 Major changes in Autoconf 2.4:
1785 Released June 14th, 1995, by David J. MacKenzie
1787 * Fix a few bugs found by Emacs testers.
1789 Major changes in Autoconf 2.3:
1791 Released March 27th, 1995, by David J. MacKenzie
1793 * Fix the cleanup trap in several ways.
1794 * Handle C compilers that are picky about option placement.
1795 * ifnames gets the version number from the right directory.
1797 Major changes in Autoconf 2.2:
1799 Released March 8th, 1995, by David J. MacKenzie
1801 * The ifnames utility is much faster but requires a "new awk" interpreter.
1802 * AC_CHECK_LIB and AC_HAVE_LIBRARY check and add the new
1803 library before existing libs, not after, in case it uses them.
1804 * New macros: AC_FUNC_GETPGRP, AC_CHECK_TOOL.
1805 * Lots of bug fixes.
1806 * Many additions to the TODO file :-)
1808 Major changes in Autoconf 2.1:
1810 Released November 4th, 1994, by David J. MacKenzie
1813 * More explanations in the manual.
1814 * Fix a spurious failure in the testsuite.
1815 * Clarify some warning messages.
1816 * autoreconf by default only rebuilds configure and config.h.in files
1817 that are older than any of their particular input files; there is a
1818 --force option to use after installing a new version of Autoconf.
1820 Thanks to everybody who's submitted changes and additions to Autoconf!
1821 I've incorporated many of them, and am still considering others for
1822 future releases -- but I didn't want to postpone this release indefinitely.
1824 Caution: don't indiscriminately rebuild configure scripts with
1825 Autoconf version 2. Some configure.in files need minor adjustments to
1826 work with it; the documentation has a chapter on upgrading. A few
1827 configure.in files, including those for GNU Emacs and the GNU C
1828 Library, need major changes because they relied on undocumented
1829 internals of version 1. Future releases of those packages will have
1830 updated configure.in files.
1832 It's best to use GNU M4 1.3 (or later) with Autoconf version 2.
1833 Autoconf now makes heavy use of M4 diversions, which were implemented
1834 inefficiently in GNU M4 releases before 1.3.
1836 Major changes in Autoconf 2.0:
1838 Released October 26th, 1994, by David J. MacKenzie
1840 ** New copyright terms:
1841 * There are no restrictions on distribution or use of configure scripts.
1844 * Autoconf manual is reorganized to make information easier to find
1845 and has several new indexes.
1846 * INSTALL is reorganized and clearer and is now made from Texinfo source.
1849 * autoscan to generate a preliminary configure.in for a package by
1850 scanning its source code for commonly used nonportable functions,
1851 programs, and header files.
1852 * ifnames to list the symbols used in #if and #ifdef directives in a
1854 * autoupdate to update a configure.in to use the version 2 macro names.
1855 * autoreconf to recursively remake configure and configuration header
1856 files in a source tree.
1858 ** Changed utilities:
1859 * autoheader can take pieces of acconfig.h to replace config.h.{top,bot}.
1860 * autoconf and autoheader can look for package-local definition files
1861 in an alternate directory.
1864 * AC_CACHE_VAL to share results of tests between configure runs.
1865 * AC_DEFUN to define macros, automatically AC_PROVIDE them, and ensure
1866 that macros invoked with AC_REQUIRE don't interrupt other macros.
1867 * AC_CONFIG_AUX_DIR, AC_CANONICAL_SYSTEM, AC_CANONICAL_HOST, AC_LINK_FILES to
1868 support deciding unguessable features based on the host and target types.
1869 * AC_CONFIG_SUBDIRS to recursively configure a source tree.
1870 * AC_ARG_PROGRAM to use the options --program-prefix,
1871 --program-suffix, and --program-transform-name to change the names
1872 of programs being installed.
1873 * AC_PREFIX_DEFAULT to change the default installation prefix.
1874 * AC_TRY_COMPILE to compile a test program without linking it.
1875 * AC_CHECK_TYPE to check whether sys/types.h or stdlib.h defines a given type.
1876 * AC_CHECK_LIB to check for a particular function and library.
1877 * AC_MSG_CHECKING and AC_MSG_RESULT to print test results, on a single line,
1878 whether or not the test succeeds. They obsolete AC_CHECKING and AC_VERBOSE.
1879 * AC_SUBST_FILE to insert one file into another.
1880 * AC_FUNC_MEMCMP to check whether memcmp is 8-bit clean.
1881 * AC_FUNC_STRFTIME to find strftime even if it's in -lintl.
1882 * AC_FUNC_GETMNTENT to find getmntent even if it's in -lsun or -lseq.
1883 * AC_HEADER_SYS_WAIT to check whether sys/wait.h is POSIX.1 compatible.
1886 * Many macros renamed systematically, but old names are accepted for
1887 backward compatibility.
1888 * AC_OUTPUT adds the "automatically generated" comment to
1889 non-Makefiles where it finds @configure_input@ in an input file, to
1890 support files with various comment syntaxes.
1891 * AC_OUTPUT does not replace "prefix" and "exec_prefix" in generated
1892 files when they are not enclosed in @ signs.
1893 * AC_OUTPUT allows the optional environment variable CONFIG_STATUS to
1894 override the file name "config.status".
1895 * AC_OUTPUT takes an optional argument for passing variables from
1896 configure to config.status.
1897 * AC_OUTPUT and AC_CONFIG_HEADER allow you to override the input-file names.
1898 * AC_OUTPUT automatically substitutes the values of CFLAGS, CXXFLAGS,
1899 CPPFLAGS, and LDFLAGS from the environment.
1900 * AC_PROG_CC and AC_PROG_CXX now set CFLAGS and CXXFLAGS, respectively.
1901 * AC_PROG_INSTALL looks for install-sh or install.sh in the directory
1902 specified by AC_CONFIG_AUXDIR, or srcdir or srcdir/.. or
1903 srcdir/../.. by default.
1904 * AC_DEFINE, AC_DEFINE_UNQUOTED, and AC_SUBST are more robust and smaller.
1905 * AC_DEFINE no longer prints anything, because of the new result reporting
1906 mechanism (AC_MSG_CHECKING and AC_MSG_RESULT).
1907 * AC_VERBOSE pays attention to --quiet/--silent, not --verbose.
1908 * AC_ARG_ENABLE and AC_ARG_WITH support whitespace in the arguments to
1909 --enable- and --with- options.
1910 * AC_CHECK_FUNCS and AC_CHECK_HEADERS take optional shell commands to
1911 execute on success or failure.
1912 * Checking for C functions in C++ works.
1915 * AC_REMOTE_TAPE and AC_RSH removed; too specific to tar and cpio, and
1916 better maintained with them.
1917 * AC_ARG_ARRAY removed because no one was likely using it.
1918 * AC_HAVE_POUNDBANG replaced with AC_SYS_INTERPRETER, which doesn't
1919 take arguments, for consistency with all of the other specific checks.
1922 * Comes with config.sub and config.guess, and uses them optionally.
1923 * Uses config.cache to cache test results. An alternate cache file
1924 can be selected with the --cache-file=FILE option.
1925 * Uses optional shell scripts $prefix/share/config.site and
1926 $prefix/etc/config.site to perform site or system specific initializations.
1927 * configure saves compiler output to ./config.log for debugging.
1928 * New files autoconf.m4 and autoheader.m4 load the other Autoconf macros.
1929 * acsite.m4 is the new name for the system-wide aclocal.m4.
1930 * Has a DejaGnu test suite.
1932 Major changes in Autoconf 1.11:
1934 * AC_PROG_INSTALL calls install.sh with the -c option.
1935 * AC_SET_MAKE cleans up after itself.
1936 * AC_OUTPUT sets prefix and exec_prefix if they weren't set already.
1937 * AC_OUTPUT prevents shells from looking in PATH for config.status.
1939 Plus a few other bug fixes.
1941 Major changes in Autoconf 1.10:
1943 * autoheader uses config.h.bot if present, analogous to config.h.top.
1944 * AC_PROG_INSTALL looks for install.sh in srcdir or srcdir/.. and
1946 * AC_PROG_CXX looks for cxx as a C++ compiler.
1948 Plus several bugs fixed.
1950 Major changes in Autoconf 1.9:
1952 * AC_YYTEXT_POINTER replaces AC_DECLARE_YYTEXT.
1953 * AC_SIZEOF_TYPE generates the cpp symbol name automatically,
1954 and autoheader generates entries for those names automatically.
1955 * AC_FIND_X gets the result from xmkmf correctly.
1956 * AC_FIND_X assumes no X if --without-x was given.
1957 * AC_FIND_XTRA adds libraries to the variable X_EXTRA_LIBS.
1958 * AC_PROG_INSTALL finds OSF/1 installbsd.
1960 Major changes in Autoconf 1.8:
1963 * New macros AC_LANG_C, AC_LANG_CPLUSPLUS, AC_LANG_SAVE, AC_LANG_RESTORE,
1964 AC_PROG_CXX, AC_PROG_CXXCPP, AC_REQUIRE_CPP
1965 for checking both C++ and C features in one configure script.
1966 * New macros AC_CHECKING, AC_VERBOSE, AC_WARN, AC_ERROR for printing messages.
1967 * New macros AC_FIND_XTRA, AC_MMAP, AC_SIZEOF_TYPE, AC_PREREQ,
1968 AC_SET_MAKE, AC_ENABLE.
1971 * AC_FIND_X looks for X in more places.
1972 * AC_PROG_INSTALL defaults to install.sh instead of cp, if it's in srcdir.
1973 install.sh is distributed with Autoconf.
1974 * AC_DECLARE_YYTEXT has been removed because it can't work, pending
1975 a rewrite of quoting in AC_DEFINE.
1976 * AC_OUTPUT adds its comments in C format when substituting in C files.
1977 * AC_COMPILE_CHECK protects its ECHO-TEXT argument with double quotes.
1979 ** New or changed command line options:
1980 * configure accepts --enable-FEATURE[=ARG] and --disable-FEATURE options.
1981 * configure accepts --without-PACKAGE, which sets withval=no.
1982 * configure accepts --x-includes=DIR and --x-libraries=DIR.
1983 * Giving --with-PACKAGE no argument sets withval=yes instead of withval=1.
1984 * configure accepts --help, --version, --silent/--quiet, --no-create options.
1985 * configure accepts and ignores most other Cygnus configure options, and
1986 warns about unknown options.
1987 * config.status accepts --help, --version options.
1989 ** File names and other changes:
1990 * Relative srcdir values are not made absolute.
1991 * The values of @prefix@ and @exec_prefix@ and @top_srcdir@ get substituted.
1992 * Autoconf library files are installed in ${datadir}/autoconf, not ${datadir}.
1993 * autoheader optionally copies config.h.top to the beginning of config.h.in.
1994 * The example Makefile dependencies for configure et al. work better.
1995 * Namespace cleanup: all shell variables used internally by Autoconf
1996 have names beginning with `ac_'.
1998 More big improvements are in process for future releases, but have not
1999 yet been (variously) finished, integrated, tested, or documented enough
2002 Major changes in Autoconf 1.7:
2004 * New macro AC_OBSOLETE.
2005 * Bugs in Makefile.in fixed.
2006 * AC_LONG_FILE_NAMES improved.
2008 Major changes in Autoconf 1.6:
2010 * New macro AC_LONG_64_BITS.
2011 * Multiple .h files can be created.
2012 * AC_FIND_X looks for X files directly if it doesn't find xmkmf.
2013 * AC_ALLOCA defines C_ALLOCA if using alloca.c.
2014 * --with-NAME can take a value, e.g., --with-targets=sun4,hp300bsd.
2015 * Unused --no-create option to configure removed.
2016 * autoheader doesn't change the timestamp of its output file if
2017 the file didn't change.
2018 * All macros that look for libraries now use AC_HAVE_LIBRARY.
2019 * config.status checks three optional environment variables to
2020 modify its behavior.
2021 * The usual bug fixes.
2023 Major changes in Autoconf 1.5:
2025 * New macros AC_FIND_X, AC_OFF_T, AC_STAT_MACROS_BROKEN, AC_REVISION.
2026 * autoconf and autoheader scripts have GNU standards conforming
2027 --version and --help options (they print their message and exit).
2030 Major changes in Autoconf 1.4:
2032 * New macros AC_HAVE_POUNDBANG, AC_TIME_WITH_SYS_TIME, AC_LONG_DOUBLE,
2033 AC_GETGROUPS_T, AC_DEFINE_UNQUOTED.
2034 * autoconf and autoheader use the M4 environment variable to determine the
2035 name of the M4 program to use.
2036 * The --macrodir option to autoconf and autoheader specifies the directory
2037 in which acspecific.m4, acgeneral.m4, etc. reside if not the default.
2038 * autoconf and autoheader can take `-' as their file names, which means to
2039 read stdin as input.
2040 * Resulting configure scripts can take a --verbose option which causes them
2041 to print the results of their tests.
2042 * AC_DEFINE quotes its second argument in such a way that spaces, magic
2043 shell characters, etc. will be preserved during various stages of
2044 expansion done by the shell. If you don't want this, use
2045 AC_DEFINE_UNQUOTED instead.
2046 * Much textual processing done with external calls to tr and sed have been
2047 internalized with builtin M4 `patsubst' and `translit' calls.
2048 * AC_OUTPUT doesn't hardwire the file names it outputs. Instead, you can
2049 set the shell variables `gen_files' and `gen_config' to the list of
2050 file names to output.
2051 * AC_DECLARE_YYTEXT does an AC_SUBST of `LEX_OUTPUT_ROOT', which may be
2052 "lex.yy" or "lexyy", depending on the system.
2053 * AC_PROGRAMS_CHECK takes an optional third arg. If given, it is used as
2055 * If AC_ALLOCA chooses alloca.c, it also defines STACK_DIRECTION.
2056 * AC_CONST works much more reliably on more systems.
2059 Major changes in Autoconf 1.3:
2061 configure no longer requires awk for packages that use a config.h.
2062 Support handling --with-PACKAGE options.
2063 New `autoheader' script to create `config.h.in' from `configure.in'.
2064 Ignore troublesome -lucb and -lPW when searching for alloca.
2065 Rename --exec_prefix to --exec-prefix for GNU standards conformance.
2066 Improve detection of STDC library.
2067 Add AC_HAVE_LIBRARY to check for non-default libraries.
2068 Function checking should work with future GNU libc releases.
2070 Major changes in Autoconf 1.2:
2072 The --srcdir option is now usually unnecessary.
2073 Add a file containing sample comments describing CPP macros.
2074 A comment in config.status tells which host it was configured on.
2075 Substituted variable values can now contain commas.
2076 Fix bugs in various feature checks.
2078 Major changes in Autoconf 1.1:
2080 Added AC_STRCOLL macro.
2081 Made AC_GETLOADAVG check for more things.
2082 AC_OUTPUT argument is now optional.
2087 Copyright (C) 1993-1996, 1998-2011 Free Software Foundation, Inc.
2089 Copying and distribution of this file, with or without modification,
2090 are permitted in any medium without royalty provided the copyright
2091 notice and this notice are preserved. This file is offered as-is,
2092 without warranty of any kind.