1 ============================================================================
4 * This file attempts to describe the rules to use when hacking
7 ============================================================================
10 * The correct response to most actual bugs is to write a new test case
11 which demonstrates the bug. Then fix the bug, re-run the test suite,
12 and check everything in.
14 * If you incorporate a change from somebody on the net:
15 - First, if it is a large change, you must make sure they have
16 signed the appropriate paperwork.
17 - Second, be sure to add their name and email address to THANKS.
19 * If a change fixes a test, mention the test in the commit message.
20 If a change fixes a bug registered in the Automake debbugs tracker,
21 mention the bug number in the commit message.
23 * If somebody reports a new bug, mention his name in the commit message
24 that fixes or exposes the bug, and put him into THANKS.
26 * When documenting a non-trivial idiom or example in the manual, be
27 sure to add a test case for it, and to reference such test case from
28 a proper Texinfo comment.
30 * Some files in the automake package are not owned by automake; these
31 files are listed in the $(FETCHFILES) variable in Makefile.am. They
32 should never be edited here. Almost all of them can be updated from
33 respective upstreams with "make fetch" (this should be done especially
34 before releases). The only exception is the 'lib/COPYING' (from FSF),
35 which should be updated by hand whenever the GPL gets updated (which
36 shouldn't happen that often anyway :-)
38 * Changes other than *trivial* bug fixes must be mentioned in NEWS.
40 * Changes which are potentially controversial, require a non-trivial
41 plan, or must be implemented gradually with a roadmap spanning several
42 releases (either minor or major) should be discussed on the list,
43 and have a proper entry in the PLANS directory. This entry should be
44 always committed in the "maint" branch, even if the change it deals
45 with is only for the master branch, or a topic branch. Usually, in
46 addition to this, it is useful to open a "wishlist" report on the
47 Automake debbugs tracker, to keep the idea more visible, and have the
48 discussions surrounding it easily archived in a central place.
50 ============================================================================
53 * We've adopted the convention that internal AC_SUBSTs and make variables
54 should be named with a leading 'am__', and internally generated targets
55 should be named with a leading 'am--'. This convention, although in
56 place from at least February 2001, isn't yet universally used.
57 But all new code should use it.
59 We used to use '_am_' as the prefix for an internal AC_SUBSTs.
60 However, it turns out that NEWS-OS 4.2R complains if a Makefile
61 variable begins with the underscore character. Yay for them.
62 I changed the target naming convention just to be safe.
64 ============================================================================
67 * Always use $(...) and not ${...}
69 * Prefer ':' over 'true', mostly for consistency with existing code.
71 * Use '##' comments liberally. Comment anything even remotely unusual.
73 * Never use basename or dirname. Instead, use sed.
75 * Do not use 'cd' within back-quotes, use '$(am__cd)' instead.
76 Otherwise the directory name may be printed, depending on CDPATH.
77 More generally, do not ever use plain 'cd' together with a relative
78 directory that does not start with a dot, or you might end up in one
81 * For install and uninstall rules, if a loop is required, it should be
82 silent. Then the body of the loop itself should print each "important"
83 command it runs. The printed commands should be preceded by a single
86 * Ensure install rules do not create any installation directory where
87 nothing is to be actually installed. See automake bug#11030.
89 ============================================================================
90 = Editing automake.in and aclocal.in
92 * Indent using GNU style. For historical reasons, the perl code
93 contains portions indented using Larry Wall's style (perl-mode's
94 default), and other portions using the GNU style (cperl-mode's
95 default). Write new code using GNU style.
97 * Don't use & for function calls, unless really required.
98 The use of & prevents prototypes from being checked.
100 ============================================================================
101 = Automake versioning and compatibility scheme
103 * There are three kinds of automake releases:
105 - new major releases (e.g., 2.0, 5.0)
106 - new minor releases (e.g., 1.14, 2.1)
107 - micro a.k.a. "bug-fixing" releases (e.g., 1.13.2, 2.0.1, 3.5.17).
109 A new major release should have the major version number bumped, and
110 the minor and micro version numbers reset to zero. A new minor release
111 should have the major version number unchanged, the minor version number
112 bumped, and the micro version number reset to zero. Finally, a new
113 micro version should have the major and minor version numbers unchanged,
114 and the micro version number bumped.
116 For example, the first minor version after 1.13.2 will be 1.14; the
117 first bug-fixing version after 1.14 that will be 1.14.1; the first
118 new major version after all such releases will be 2.0; the first
119 bug-fixing version after 2.0 will be 2.0.1; and a further bug-fixing
120 version after 2.0.1 will be 2.0.2.
122 * Micro releases should be just bug-fixing releases; no new features
123 should be added, and ideally, only trivial bugs, recent regressions,
124 or documentation issues should be addressed by them.
126 * Minor releases can introduce new "safe" features, do non-trivial but
127 mostly safe code clean-ups, and even add new runtime warnings (rigorously
128 non-fatal). But they shouldn't include any backward incompatible change,
129 nor contain any potentially destabilizing refactoring or sweeping change,
130 nor introduce new features whose implementation might be liable to cause
131 bugs or regressions in existing code. However, it might be acceptable to
132 introduce very limited and localized backward-incompatibilities, *only*
133 if that is necessary to fix non-trivial bugs, address serious performance
134 issues, or greatly enhance usability. But please, do this sparsely and
137 * Major releases can introduce backward-incompatibilities (albeit such
138 incompatibilities should be announced well in advance, and a smooth
139 transition plan prepared for them), and try more risking and daring
140 refactorings and code cleanups.
142 * For more information, refer to the extensive discussion associated
143 with automake bug#13578.
145 ============================================================================
148 * To regenerate dependent files created by aclocal and automake,
149 use the 'bootstrap.sh' script. It uses the code from the source
150 tree, so the resulting files (aclocal.m4 and Makefile.in) should
151 be the same as you would get if you install this version of
152 automake and use it to generate those files. Be sure to have the
153 latest stable version of Autoconf installed and available early
156 * The Automake git tree currently carries three basic branches: 'micro',
157 'maint' and 'master'.
159 * The 'micro' branch, reserved to changes that should go into the next
160 micro release; so it will just see fixes for regressions, trivial
161 bugs, or documentation issues, and no "active" development whatsoever.
162 Since emergency regression-fixing or security releases could be cut
163 from this branch at any time, it should always be kept in a releasable
166 * The 'maint' branch is where the development of the next minor release
167 takes place. It should be kept in a stable, almost-releasable state,
168 to simplify testing and deploying of new minor version. Note that
169 this is not a hard rule, and such "stability" is not expected to be
170 absolute (emergency releases are cut from the 'micro' branch anyway).
172 * The 'master' branch is reserved for the development of the next major
173 release. Experimenting a little is OK here, but don't let the branch
174 grow too unstable; if you need to do exploratory programming or
175 over-arching change, you should use a dedicated topic branch, and
176 only merge that back once it is reasonably stable.
178 * The 'micro' branch should be kept regularly merged into the 'maint'
179 branch, and the 'maint' branch into the 'master' branch. It is advisable
180 to merge only after a set of related commits have been applied, to avoid
181 introducing too much noise in the history.
183 * There may be a number of longer-lived feature branches for new
184 developments. They should be based off of a common ancestor of all
185 active branches to which the feature should or might be merged later.
187 * After a new minor release is done, the 'maint' branch is to be merged
188 into the 'micro' branch, and then a "new" 'maint' branch created
189 stemming from the resulting commit.
190 Similarly, after a new major release is done, the 'master' branch is to
191 be merged into both the 'micro' and 'maint' branches, and then "new"
192 'master' branch created stemming from the resulting commit.
194 * When fixing a bug (especially a long-standing one), it may be useful
195 to commit the fix to a new temporary branch based off the commit that
196 introduced the bug. Then this "bugfix branch" can be merged into all
197 the active branches descending from the buggy commit. This offers a
198 simple way to fix the bug consistently and effectively.
200 * When merging, prefer 'git merge --log' over plain 'git merge', so that
201 a later 'git log' gives an indication of which actual patches were
202 merged even when they don't appear early in the list.
204 * The 'master', 'maint' and 'micro' branches should not be rewound, i.e.,
205 should always fast-forward, except maybe for privacy issues. For
206 feature branches, the announcement for the branch should document
207 the rewinding policy.
208 If a topic branch is expected to be rewound, it is good practice to put
209 it in the 'experimental/*' namespace; for example, a rewindable branch
210 dealing with Vala support could be named like "experimental/vala-work".
212 ============================================================================
213 = Writing a good commit message
215 * Here is the general format that Automake's commit messages are expected
216 to follow. See the further points below for clarifications and minor
219 topic: brief description (this is the "summary line")
221 <reference to relevant bugs, if any>
223 Here goes a more detailed explanation of why the commit is needed,
224 and a general overview of what it does, and how. This section
225 should almost always be provided, possibly only with the expection
226 of obvious fixes or very trivial changes.
228 And if the detailed explanation is quite long or detailed, you can
229 want to break it in more paragraphs.
231 Then you can add references to relevant mailing list discussions
232 (if any), with proper links. But don't take this as an excuse for
233 writing incomplete commit messages! The "distilled" conclusions
234 reached in such discussions should have been placed in the
237 Finally, here you can thank people that motivated or helped the
238 change. So, thanks to John Doe for bringing up the issue, and to
239 J. Random Hacker for providing suggestions and testing the patch.
241 <detailed list of touched files>
243 * The <detailed list of touched files> should usually be provided (but
244 for short or trivial changes), and should follow the GNU guidelines
245 for ChangeLog entries (described explicitly in the GNU Coding
246 Standards); it might be something of this sort:
248 * some/file (func1): Improved frobnication.
249 (func2): Adjusted accordingly.
250 * another/file (foo, bar): Likewise.
251 * tests/foo.tap: New test.
252 * tests/Makefile.am (TESTS): Add it.
254 * If your commit fixes an automake bug registered in the tracker (say
255 numbered 1234), you should put the following line after the summary
258 This change fixes automake bug#1234.
260 * If your commit is just related to the given bug report, but does not
261 fix it, you might want to add a line like this instead:
263 This change is related to automake bug#1234.
265 * When referring to older commits, use 'git describe' output as pointer.
266 But also try to identify the given commit by date and/or summary line
267 if possible. Examples:
269 Since yesterday's commit, v1.11-2019-g4d2bf42, ...
271 ... removed in commit 'v1.11-1674-g02e9072' of 01-01-2012,
272 "dist: ditch support for lzma"...
274 ============================================================================
277 * Use "make check" and "make maintainer-check" liberally.
279 * Export the 'keep_testdirs' environment variable to "yes" to keep
280 test directories for successful tests also.
282 * Use perl coverage information to ensure your new code is thoroughly
283 tested by your new tests.
285 * See file 't/README' for more information.
287 ============================================================================
290 * The steps outlined here are meant to be followed for alpha and stable
291 releases as well. Where differences are expected, they will be
292 explicitly described.
294 * Fetch new versions of the files that are maintained by the FSF by
295 running "make fetch". In case any file in the automake repository
296 has been updated, commit and re-run the testsuite.
298 * Ensure that the copyright notices of the distributed files is up to
299 date. The maintainer-only target "update-copyright" can help with
302 * Check NEWS; in particular, ensure that all the relevant differences
303 with the last release are actually reported.
305 * Update the version number in configure.ac.
306 (The idea is that every other alpha number will be a net release.
307 The repository will always have its own "odd" number so we can easily
308 distinguish net and repo versions.)
310 * Run these commands, in this order:
313 make check keep_testdirs=yes
314 make maintainer-check
316 make check-no-trailing-backslash-in-recipes
319 It is also advised to run "git clean -fdx" before invoking the
320 bootstrap, to ensure a really clean rebuild. However, it must
321 be done carefully, because that command will remove *all* the
322 files that are not tracked by git!
324 * Run "make git-tag-release".
325 This will run the maintainer checks, verify that the local git
326 repository and working tree are clean and up-to-date, and create
327 a proper signed git tag for the release (based on the contents
330 * Run "make git-upload-release".
331 This will first verify that you are releasing from a tagged version
332 and that the local git repository and working tree are clean and
333 up-to-date, and will then run "make dist" to create the tarballs,
334 and invoke the 'gnupload' script sign and upload them to the correct
335 locations. In case you need to sign with a non-default key, you can
336 use "make GNUPLOADFLAGS='--user KEY' git-upload-release".
338 * For stable releases you'll have to update the manuals at www.gnu.org.
340 - Generate manuals (with the help of the standard gendocs.sh script):
344 The ready-to-be-uploaded manuals (in several formats) will be left
345 in the 'doc/web-manuals' directory.
347 - Commit the updated manuals to web CVS:
349 make web-manual-update
351 If your local username is different from your username at Savannah,
352 you'll have to override the 'CVS_USER' make variable accordingly;
355 make web-manual-update CVS_USER=slattarini
357 - Check for link errors, fix them, recheck until convergence:
358 <http://validator.w3.org/checklink>
360 * Create an announcement message with "make announcement". Edit the
361 generated 'announcement' file appropriately, in particularly filling
362 in by hand any "TODO" left in there.
364 * Update version number in configure.ac to next alpha number.
365 Re-run ./bootstrap.sh and commit.
367 * Don't forget to "git push" your changes so they appear in the public
370 * Send the announcement generated in the earlier steps at least to
371 <autotools-announce@gnu.org> and <automake@gnu.org>. If the release
372 is a stable one, the announcement must also go to <info-gnu@gnu.org>;
373 if it is an alpha or beta release, announcement should be sent also
374 to <platform-testers@gnu.org>, to maximize the possibility of early
375 testing on exotic or proprietary systems. Finally, copy an abridged
376 version of the announcement into the NEWS feed at:
377 <https://savannah.gnu.org/projects/automake>.
378 Be sure to link a version to the complete announcement (from
379 the version you sent to the automake list, as get archived on
380 <http://lists.gnu.org/archive/html/automake/>).
384 Copyright (C) 2003-2013 Free Software Foundation, Inc.
386 This program is free software; you can redistribute it and/or modify
387 it under the terms of the GNU General Public License as published by
388 the Free Software Foundation; either version 2, or (at your option)
391 This program is distributed in the hope that it will be useful,
392 but WITHOUT ANY WARRANTY; without even the implied warranty of
393 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
394 GNU General Public License for more details.
396 You should have received a copy of the GNU General Public License
397 along with this program. If not, see <http://www.gnu.org/licenses/>.