1129199ScognetMajor changes in release 2.13:
2129199Scognet
3129199Scognet* Support for building on Win32 systems where the only available C or
4129199Scognet  C++ compiler is the Microsoft Visual C++ command line compiler
5129199Scognet  (`cl').  Additional support for building on Win32 systems which are
6129199Scognet  using the Cygwin or Mingw32 environments.
7129199Scognet* Support for alternative object file and executable file extensions.
8129199Scognet  On Win32, for example, these are .obj and .exe. These are discovered
9129199Scognet  using AC_OBJEXT and AC_EXEEXT, which substitute @OBJEXT@ and
10129199Scognet  @EXEEXT@ in the output, respectively.
11135670Scognet* New macros: AC_CACHE_LOAD, AC_CACHE_SAVE, AC_FUNC_SELECT_ARGTYPES,
12129199Scognet  AC_VALIDATE_CACHED_SYSTEM_TUPLE, AC_SEARCH_LIBS, AC_TRY_LINK_FUNC,
13129199Scognet  AC_C_STRINGIZE, AC_CHECK_FILE(S), AC_PROG_F77 (and friends).
14129199Scognet* AC_DEFINE now has an optional third argument for a description to be
15135670Scognet  placed in the config header input file (e.g. config.h.in).
16129199Scognet* The C++ code fragment compiled for the C++ compiler test had to be
17129199Scognet  improved to include an explicit return type for main(). This was
18129199Scognet  causing failures on systems using recent versions of the EGCS C++
19129199Scognet  compiler.
20169612Swkoszek* Fixed an important bug in AC_CHECK_TYPE that would cause a configure
21129199Scognet  script to report that `sometype_t' was present when only `type_t'
22129199Scognet  was defined.
23129199Scognet* Merge of the FSF version of config.guess and config.sub to modernise
24129199Scognet  these scripts. Add support for a few new hosts in config.guess.
25129199Scognet  Incorporate latest versions of install-sh, mkinstalldirs and
26129199Scognet  texinfo.tex from the FSF. 
27129199Scognet* autoreconf is capable of running automake if necessary (and
28129199Scognet  applicable).
29129199Scognet* Support for Fortran 77. See the Texinfo documentation for details.
30129199Scognet* Bug fixes and workarounds for quirky bugs in vendor utilities.
31129199Scognet
32129199ScognetMajor changes in release 2.12:
33209131Sraj
34209131Sraj* AC_OUTPUT and AC_CONFIG_HEADER can create output files by
35135670Scognet  concatenating multiple input files separated by colons, like so:
36135670Scognet  AC_CONFIG_HEADER(config.h:conf.pre:config.h.in:conf.post)
37140479Scognet  AC_OUTPUT(Makefile:Makefile.in:Makefile.rules)
38157165Scognet  The arguments may be shell variables, to compute the lists on the fly.
39153112Scognet* AC_LINK_FILES and AC_CONFIG_SUBDIRS may be called multiple times.
40147630Scognet* New macro AC_OUTPUT_COMMANDS adds more commands to run in config.status.
41150862Scognet* Bug fixes.
42248126Sandrew
43245838SandrewMajor changes in release 2.11:
44248126Sandrew
45245838Sandrew* AC_PROG_CC and AC_PROG_CXX check whether the compiler works.
46160629Scognet  They also default CFLAGS/CXXFLAGS to "-g -O2" for gcc, instead of "-g -O".
47248365Sandrew* AC_REPLACE_FUNCS defines HAVE_foo if the system has the function `foo'.
48160629Scognet* AC_CONFIG_HEADER expands shell variables in its argument.
49248365Sandrew* New macros: AC_FUNC_FNMATCH, AC_FUNC_SETPGRP.
50245675Sandrew* The "checking..." messages and the source code for test programs that
51245675Sandrew  fail are saved in config.log. 
52248126Sandrew* Another workaround has been added for seds with small command length limits.
53248126Sandrew* config.sub and config.guess recognize more system types.
54248126Sandrew* Bug fixes.
55160629Scognet
56248126SandrewMajor changes in release 2.10:
57160629Scognet
58243664Smarcel* Bug fixes.
59152742Scognet* The cache variable names used by `AC_CHECK_LIB(LIB, FUNC, ...)' has
60152742Scognet  changed: now $ac_cv_lib_LIB_FUNC, previously $ac_cv_lib_LIB.
61153549Scognet
62152742ScognetMajor changes in releases 2.6 through 2.9:
63152742Scognet
64152742Scognet* Bug fixes.
65152742Scognet
66152742ScognetMajor changes in release 2.5:
67153566Scognet
68175984Sraj* New configure options --bindir, --libdir, --datadir, etc., with
69175984Sraj  corresponding output variables.
70175984Sraj* New macro: AC_CACHE_CHECK, to make using the cache easier.
71175984Sraj* config.log contains the command being run as well as any output from it.
72159084Scognet* AC_CHECK_LIB can check for libraries with "." or "/" or "+" in their name.
73159084Scognet* AC_PROG_INSTALL doesn't cache a path to install-sh, for sharing caches.
74159084Scognet* AC_CHECK_PROG, AC_PATH_PROG, AC_CHECK_PROGS, AC_PATH_PROGS, and
75171619Scognet  AC_CHECK_TOOL can search a path other than $PATH.
76183840Sraj* AC_CHECK_SIZEOF takes an optional size to use when cross-compiling.
77239268Sgonzo
78239268SgonzoMajor changes in release 2.4:
79239268Sgonzo
80177895Simp* Fix a few bugs found by Emacs testers.
81177895Simp
82153566ScognetMajor changes in release 2.3:
83159758Scognet
84153566Scognet* Fix the cleanup trap in several ways.
85153566Scognet* Handle C compilers that are picky about option placement.
86153549Scognet* ifnames gets the version number from the right directory.
87248362Sandrew
88171619ScognetMajor changes in release 2.2:
89171619Scognet
90171619Scognet* The ifnames utility is much faster but requires a "new awk" interpreter.
91153549Scognet* AC_CHECK_LIB and AC_HAVE_LIBRARY check and add the new
92248362Sandrew  library before existing libs, not after, in case it uses them.
93159557Scognet* New macros: AC_FUNC_GETPGRP, AC_CHECK_TOOL.
94248362Sandrew* Lots of bug fixes.
95181294Scognet* Many additions to the TODO file :-)
96248362Sandrew
97248362SandrewMajor changes in release 2.1:
98181294Scognet
99248362Sandrew* Fix C++ problems.
100248362Sandrew* More explanations in the manual.
101248363Sandrew* Fix a spurious failure in the testsuite.
102248363Sandrew* Clarify some warning messages.
103248362Sandrew* autoreconf by default only rebuilds configure and config.h.in files
104153566Scognet  that are older than any of their particular input files; there is a
105248362Sandrew  --force option to use after installing a new version of Autoconf.
106154561Scognet
107248362SandrewThanks to everybody who's submitted changes and additions to Autoconf!
108238464SimpI've incorporated many of them, and am still considering others for
109153112Scognetfuture releases -- but I didn't want to postpone this release indefinitely.
110248362Sandrew
111223116ScognetCaution: don't indiscriminately rebuild configure scripts with
112223116ScognetAutoconf version 2.  Some configure.in files need minor adjustments to
113181294Scognetwork with it; the documentation has a chapter on upgrading.  A few
114248362Sandrewconfigure.in files, including those for GNU Emacs and the GNU C
115248362SandrewLibrary, need major changes because they relied on undocumented
116181294Scognetinternals of version 1.  Future releases of those packages will have
117248362Sandrewupdated configure.in files.
118248362Sandrew
119248362SandrewIt's best to use GNU m4 1.3 (or later) with Autoconf version 2.
120153112ScognetAutoconf now makes heavy use of m4 diversions, which were implemented
121248363Sandrewinefficiently in GNU m4 releases before 1.3.
122153549Scognet
123248362SandrewMajor changes in release 2.0:
124150862Scognet
125185478Ssam** New copyright terms:
126185478Ssam* There are no restrictions on distribution or use of configure scripts.
127129199Scognet
128129199Scognet** Documentation:
129129199Scognet* Autoconf manual is reorganized to make information easier to find
130129199Scognet  and has several new indexes.
131129199Scognet* INSTALL is reorganized and clearer and is now made from Texinfo source.
132129199Scognet
133129199Scognet** New utilities:
134129199Scognet* autoscan to generate a preliminary configure.in for a package by
135129199Scognet  scanning its source code for commonly used nonportable functions,
136129199Scognet  programs, and header files.
137129199Scognet* ifnames to list the symbols used in #if and #ifdef directives in a
138129199Scognet  source tree.
139153549Scognet* autoupdate to update a configure.in to use the version 2 macro names.
140153549Scognet* autoreconf to recursively remake configure and configuration header
141153549Scognet  files in a source tree.
142153549Scognet
143153549Scognet** Changed utilities:
144153549Scognet* autoheader can take pieces of acconfig.h to replace config.h.{top,bot}.
145135670Scognet* autoconf and autoheader can look for package-local definition files
146135670Scognet  in an alternate directory.
147135670Scognet
148129199Scognet** New macros:
149129199Scognet* AC_CACHE_VAL to share results of tests between configure runs.
150129199Scognet* AC_DEFUN to define macros, automatically AC_PROVIDE them, and ensure
151  that macros invoked with AC_REQUIRE don't interrupt other macros.
152* AC_CONFIG_AUX_DIR, AC_CANONICAL_SYSTEM, AC_CANONICAL_HOST, AC_LINK_FILES to
153  support deciding unguessable features based on the host and target types.
154* AC_CONFIG_SUBDIRS to recursively configure a source tree.
155* AC_ARG_PROGRAM to use the options --program-prefix,
156  --program-suffix, and --program-transform-name to change the names
157  of programs being installed.
158* AC_PREFIX_DEFAULT to change the default installation prefix.
159* AC_TRY_COMPILE to compile a test program without linking it.
160* AC_CHECK_TYPE to check whether sys/types.h or stdlib.h defines a given type.
161* AC_CHECK_LIB to check for a particular function and library.
162* AC_MSG_CHECKING and AC_MSG_RESULT to print test results, on a single line,
163  whether or not the test succeeds.  They obsolete AC_CHECKING and AC_VERBOSE.
164* AC_SUBST_FILE to insert one file into another.
165* AC_FUNC_MEMCMP to check whether memcmp is 8-bit clean.
166* AC_FUNC_STRFTIME to find strftime even if it's in -lintl.
167* AC_FUNC_GETMNTENT to find getmntent even if it's in -lsun or -lseq.
168* AC_HEADER_SYS_WAIT to check whether sys/wait.h is POSIX.1 compatible.
169
170** Changed macros:
171* Many macros renamed systematically, but old names are accepted for
172  backward compatibility.
173* AC_OUTPUT adds the "automatically generated" comment to
174  non-Makefiles where it finds @configure_input@ in an input file, to
175  support files with various comment syntaxes.
176* AC_OUTPUT does not replace "prefix" and "exec_prefix" in generated
177  files when they are not enclosed in @ signs.
178* AC_OUTPUT allows the optional environment variable CONFIG_STATUS to
179  override the file name "config.status".
180* AC_OUTPUT takes an optional argument for passing variables from
181  configure to config.status.
182* AC_OUTPUT and AC_CONFIG_HEADER allow you to override the input-file names.
183* AC_OUTPUT automatically substitutes the values of CFLAGS, CXXFLAGS,
184  CPPFLAGS, and LDFLAGS from the environment.
185* AC_PROG_CC and AC_PROG_CXX now set CFLAGS and CXXFLAGS, respectively.
186* AC_PROG_INSTALL looks for install-sh or install.sh in the directory
187  specified by AC_CONFIG_AUXDIR, or srcdir or srcdir/.. or
188  srcdir/../.. by default.
189* AC_DEFINE, AC_DEFINE_UNQUOTED, and AC_SUBST are more robust and smaller.
190* AC_DEFINE no longer prints anything, because of the new result reporting
191  mechanism (AC_MSG_CHECKING and AC_MSG_RESULT).
192* AC_VERBOSE pays attention to --quiet/--silent, not --verbose.
193* AC_ARG_ENABLE and AC_ARG_WITH support whitespace in the arguments to
194  --enable- and --with- options.
195* AC_CHECK_FUNCS and AC_CHECK_HEADERS take optional shell commands to
196  execute on success or failure.
197* Checking for C functions in C++ works.
198
199** Removed macros:
200* AC_REMOTE_TAPE and AC_RSH removed; too specific to tar and cpio, and
201  better maintained with them.
202* AC_ARG_ARRAY removed because no one was likely using it.
203* AC_HAVE_POUNDBANG replaced with AC_SYS_INTERPRETER, which doesn't
204  take arguments, for consistency with all of the other specific checks.
205
206** New files:
207* Comes with config.sub and config.guess, and uses them optionally.
208* Uses config.cache to cache test results.  An alternate cache file
209  can be selected with the --cache-file=FILE option.
210* Uses optional shell scripts $prefix/share/config.site and
211  $prefix/etc/config.site to perform site or system specific initializations.
212* configure saves compiler output to ./config.log for debugging.
213* New files autoconf.m4 and autoheader.m4 load the other Autoconf macros.
214* acsite.m4 is the new name for the system-wide aclocal.m4.
215* Has a DejaGnu test suite.
216
217Major changes in release 1.11:
218
219* AC_PROG_INSTALL calls install.sh with the -c option.
220* AC_SET_MAKE cleans up after itself.
221* AC_OUTPUT sets prefix and exec_prefix if they weren't set already.
222* AC_OUTPUT prevents shells from looking in PATH for config.status.
223
224Plus a few other bug fixes.
225
226Major changes in release 1.10:
227
228* autoheader uses config.h.bot if present, analogous to config.h.top.
229* AC_PROG_INSTALL looks for install.sh in srcdir or srcdir/.. and
230  never uses cp.
231* AC_PROG_CXX looks for cxx as a C++ compiler.
232
233Plus several bugs fixed.
234
235Major changes in release 1.9:
236
237* AC_YYTEXT_POINTER replaces AC_DECLARE_YYTEXT.
238* AC_SIZEOF_TYPE generates the cpp symbol name automatically,
239  and autoheader generates entries for those names automatically.
240* AC_FIND_X gets the result from xmkmf correctly.
241* AC_FIND_X assumes no X if --without-x was given.
242* AC_FIND_XTRA adds libraries to the variable X_EXTRA_LIBS.
243* AC_PROG_INSTALL finds OSF/1 installbsd.
244
245Major changes in release 1.8:
246
247** New macros:
248* New macros AC_LANG_C, AC_LANG_CPLUSPLUS, AC_LANG_SAVE, AC_LANG_RESTORE,
249  AC_PROG_CXX, AC_PROG_CXXCPP, AC_REQUIRE_CPP
250  for checking both C++ and C features in one configure script.
251* New macros AC_CHECKING, AC_VERBOSE, AC_WARN, AC_ERROR for printing messages.
252* New macros AC_FIND_XTRA, AC_MMAP, AC_SIZEOF_TYPE, AC_PREREQ,
253  AC_SET_MAKE, AC_ENABLE.
254
255** Changed macros:
256* AC_FIND_X looks for X in more places.
257* AC_PROG_INSTALL defaults to install.sh instead of cp, if it's in srcdir.
258  install.sh is distributed with Autoconf.
259* AC_DECLARE_YYTEXT has been removed because it can't work, pending
260  a rewrite of quoting in AC_DEFINE.
261* AC_OUTPUT adds its comments in C format when substituting in C files.
262* AC_COMPILE_CHECK protects its ECHO-TEXT argument with double quotes.
263
264** New or changed command line options:
265* configure accepts --enable-FEATURE[=ARG] and --disable-FEATURE options.
266* configure accepts --without-PACKAGE, which sets withval=no.
267* configure accepts --x-includes=DIR and --x-libraries=DIR.
268* Giving --with-PACKAGE no argument sets withval=yes instead of withval=1.
269* configure accepts --help, --version, --silent/--quiet, --no-create options.
270* configure accepts and ignores most other Cygnus configure options, and
271  warns about unknown options.
272* config.status accepts --help, --version options.
273
274** Paths and other changes:
275* Relative srcdir values are not made absolute.
276* The values of @prefix@ and @exec_prefix@ and @top_srcdir@ get substituted.
277* Autoconf library files are installed in ${datadir}/autoconf, not ${datadir}.
278* autoheader optionally copies config.h.top to the beginning of config.h.in.
279* The example Makefile dependencies for configure et al. work better.
280* Namespace cleanup: all shell variables used internally by Autoconf
281  have names beginning with `ac_'.
282
283More big improvements are in process for future releases, but have not
284yet been (variously) finished, integrated, tested, or documented enough
285to release yet.
286
287Major changes in release 1.7:
288
289* New macro AC_OBSOLETE.
290* Bugs in Makefile.in fixed.
291* AC_LONG_FILE_NAMES improved.
292
293Major changes in release 1.6:
294
295* New macro AC_LONG_64_BITS.
296* Multiple .h files can be created.
297* AC_FIND_X looks for X files directly if it doesn't find xmkmf.
298* AC_ALLOCA defines C_ALLOCA if using alloca.c.
299* --with-NAME can take a value, e.g., --with-targets=sun4,hp300bsd.
300* Unused --no-create option to configure removed.
301* autoheader doesn't change the timestamp of its output file if
302  the file didn't change.
303* All macros that look for libraries now use AC_HAVE_LIBRARY.
304* config.status checks three optional environment variables to
305  modify its behavior.
306* The usual bug fixes.
307
308Major changes in release 1.5:
309
310* New macros AC_FIND_X, AC_OFF_T, AC_STAT_MACROS_BROKEN, AC_REVISION.
311* autoconf and autoheader scripts have GNU standards conforming
312  --version and --help options (they print their message and exit).
313* Many bug fixes.
314
315Major changes in release 1.4:
316
317* New macros AC_HAVE_POUNDBANG, AC_TIME_WITH_SYS_TIME, AC_LONG_DOUBLE,
318  AC_GETGROUPS_T, AC_DEFINE_UNQUOTED.
319* autoconf and autoheader use the M4 environment variable to determine the
320  path of the m4 program to use.
321* The --macrodir option to autoconf and autoheader specifies the directory
322  in which acspecific.m4, acgeneral.m4, etc. reside if not the default.
323* autoconf and autoheader can take `-' as their file names, which means to
324  read stdin as input.
325* Resulting configure scripts can take a --verbose option which causes them
326  to print the results of their tests.
327* AC_DEFINE quotes its second argument in such a way that spaces, magic
328  shell characters, etc. will be preserved during various stages of
329  expansion done by the shell.  If you don't want this, use
330  AC_DEFINE_UNQUOTED instead.
331* Much textual processing done with external calls to tr and sed have been
332  internalized with builtin m4 `patsubst' and `translit' calls.
333* AC_OUTPUT doesn't hardwire the filenames it outputs.  Instead, you can
334  set the shell variables `gen_files' and `gen_config' to the list of
335  filenames to output.
336* AC_DECLARE_YYTEXT does an AC_SUBST of `LEX_OUTPUT_ROOT', which may be
337  "lex.yy" or "lexyy", depending on the system.
338* AC_PROGRAMS_CHECK takes an optional third arg.  If given, it is used as
339  the default value.
340* If AC_ALLOCA chooses alloca.c, it also defines STACK_DIRECTION.
341* AC_CONST works much more reliably on more systems.
342* Many bug fixes.
343
344Major changes in release 1.3:
345
346configure no longer requires awk for packages that use a config.h.
347Support handling --with-PACKAGE options.
348New `autoheader' script to create `config.h.in' from `configure.in'.
349Ignore troublesome -lucb and -lPW when searching for alloca.
350Rename --exec_prefix to --exec-prefix for GNU standards conformance.
351Improve detection of STDC library.
352Add AC_HAVE_LIBRARY to check for non-default libraries.
353Function checking should work with future GNU libc releases.
354
355Major changes in release 1.2:
356
357The --srcdir option is now usually unnecessary.
358Add a file containing sample comments describing CPP macros.
359A comment in config.status tells which host it was configured on.
360Substituted variable values can now contain commas.
361Fix bugs in various feature checks.
362
363Major changes in release 1.1:
364
365Added AC_STRCOLL macro.
366Made AC_GETLOADAVG check for more things.
367AC_OUTPUT argument is now optional.
368Various bug fixes.
369