am-ft: make the environment available earlier

[platform/upstream/automake.git] / HACKING

diff --git a/HACKING b/HACKING
index 604bf67..fdadada 100644 (file)
--- a/HACKING
+++ b/HACKING
@@ -12,16 +12,16 @@
   and check everything in.
 
 * If you incorporate a change from somebody on the net:
   and check everything in.
 
 * If you incorporate a change from somebody on the net:

-  First, if it is a large change, you must make sure they have signed the
-  appropriate paperwork.
-  Second, be sure to add their name and email address to THANKS
+  - First, if it is a large change, you must make sure they have
+    signed the appropriate paperwork.
+  - Second, be sure to add their name and email address to THANKS.

 
 * If a change fixes a test, mention the test in the commit message.
   If a change fixes a bug registered in the Automake debbugs tracker,
   mention the bug number in the commit message.
 
 * If somebody reports a new bug, mention his name in the commit message
 
 * If a change fixes a test, mention the test in the commit message.
   If a change fixes a bug registered in the Automake debbugs tracker,
   mention the bug number in the commit message.
 
 * If somebody reports a new bug, mention his name in the commit message

-  and in the test case you write.  Put him into THANKS.
+  that fixes or exposes the bug, and put him into THANKS.

 
 * When documenting a non-trivial idiom or example in the manual, be
   sure to add a test case for it, and to reference such test case from
 
 * When documenting a non-trivial idiom or example in the manual, be
   sure to add a test case for it, and to reference such test case from


@@ -35,19 +35,28 @@
   which should be updated by hand whenever the GPL gets updated (which
   shouldn't happen that often anyway :-)
 
   which should be updated by hand whenever the GPL gets updated (which
   shouldn't happen that often anyway :-)
 

-* Changes other than bug fixes must be mentioned in NEWS.  Important
-  bug fixes should be mentioned in NEWS, too.
+* Changes other than *trivial* bug fixes must be mentioned in NEWS.
+
+* Changes which are potentially controversial, require a non-trivial
+  plan, or must be implemented gradually with a roadmap spanning several
+  releases (either minor or major) should be discussed on the list,
+  and have a proper entry in the PLANS directory.  This entry should be
+  always committed in the "maint" branch, even if the change it deals
+  with is only for the master branch, or a topic branch.  Usually, in
+  addition to this, it is useful to open a "wishlist" report on the
+  Automake debbugs tracker, to keep the idea more visible, and have the
+  discussions surrounding it easily archived in a central place.

 
 ============================================================================
 = Naming
 
 
 ============================================================================
 = Naming
 

-* We've adopted the convention that internal AC_SUBSTs should be
-  named with a leading 'am__', and internally generated targets
-  should be named with a leading 'am--'.  This convention, although
-  in place from at least February 2001, isn't yet universally used.
+* We've adopted the convention that internal AC_SUBSTs and make variables
+  should be named with a leading 'am__', and internally generated targets
+  should be named with a leading 'am--'.  This convention, although in
+  place from at least February 2001, isn't yet universally used.

   But all new code should use it.
 
   But all new code should use it.
 

-  We used to use '_am_' as the prefix for an internal AC_SUBST.
+  We used to use '_am_' as the prefix for an internal AC_SUBSTs.

   However, it turns out that NEWS-OS 4.2R complains if a Makefile
   variable begins with the underscore character.  Yay for them.
   I changed the target naming convention just to be safe.
   However, it turns out that NEWS-OS 4.2R complains if a Makefile
   variable begins with the underscore character.  Yay for them.
   I changed the target naming convention just to be safe.


@@ -57,12 +66,11 @@
 
 * Always use $(...) and not ${...}
 
 
 * Always use $(...) and not ${...}
 

-* Use ':', not 'true'.  Use 'exit 1', not 'false'.
+* Prefer ':' over 'true', mostly for consistency with existing code.

 
 

-* Use '##' comments liberally.  Comment anything even remotely
-  unusual.
+* Use '##' comments liberally.  Comment anything even remotely unusual.

 
 

-* Never use basename or dirname.  Instead use sed.
+* Never use basename or dirname.  Instead, use sed.

 
 * Do not use 'cd' within back-quotes, use '$(am__cd)' instead.
   Otherwise the directory name may be printed, depending on CDPATH.
 
 * Do not use 'cd' within back-quotes, use '$(am__cd)' instead.
   Otherwise the directory name may be printed, depending on CDPATH.


@@ -71,9 +79,9 @@
   computed with CDPATH.
 
 * For install and uninstall rules, if a loop is required, it should be
   computed with CDPATH.
 
 * For install and uninstall rules, if a loop is required, it should be

-  silent.  Then the body of the loop itself should print each
-  "important" command it runs.  The printed commands should be preceded
-  by a single space.
+  silent.  Then the body of the loop itself should print each "important"
+  command it runs.  The printed commands should be preceded by a single
+  space.

 
 * Ensure install rules do not create any installation directory where
   nothing is to be actually installed.  See automake bug#11030.
 
 * Ensure install rules do not create any installation directory where
   nothing is to be actually installed.  See automake bug#11030.


@@ -86,11 +94,8 @@
   default), and other portions using the GNU style (cperl-mode's
   default).  Write new code using GNU style.
 
   default), and other portions using the GNU style (cperl-mode's
   default).  Write new code using GNU style.
 

-* Don't use & for function calls, unless required.
+* Don't use & for function calls, unless really required.

   The use of & prevents prototypes from being checked.
   The use of & prevents prototypes from being checked.

-  Just as above, don't change massively all the code to strip the
-  &, just convert the old code as you work on it, and write new
-  code without.

 
 ============================================================================
 = Automake versioning and compatibility scheme
 
 ============================================================================
 = Automake versioning and compatibility scheme


@@ -116,20 +121,26 @@
 
 * Micro releases should be just bug-fixing releases; no new features
   should be added, and ideally, only trivial bugs, recent regressions,
 
 * Micro releases should be just bug-fixing releases; no new features
   should be added, and ideally, only trivial bugs, recent regressions,

-  or documentation issues should be addressed by them.
-
-* Minor releases can introduce new "safe" features, do non-trivial
-  but mostly safe code clean-ups, and even add new runtime warnings
-  (rigorously non-fatal); but they shouldn't include any backward
-  incompatible change, nor contain any potentially destabilizing
-  refactoring or sweeping change, nor introduce new features whose
-  implementation might be liable to cause bugs or regressions in
-  existing code.
-
-* Major releases can introduce backward-incompatibilities (albeit
-  such incompatibilities should be announced well in advance, and
-  a smooth transition plan prepared for them), and try more risking
-  and daring refactorings and code cleanups.
+  or documentation issues should be addressed by them.  On the other
+  hand, it's OK to include testsuite work and even testsuite refactoring
+  in a micro version, since a regression there is not going to annoy or
+  inconvenience Automake users, but only the Automake developers.
+
+* Minor releases can introduce new "safe" features, do non-trivial but
+  mostly safe code clean-ups, and even add new runtime warnings (rigorously
+  non-fatal).  But they shouldn't include any backward incompatible change,
+  nor contain any potentially destabilizing refactoring or sweeping change,
+  nor introduce new features whose implementation might be liable to cause
+  bugs or regressions in existing code.  However, it might be acceptable to
+  introduce very limited and localized backward-incompatibilities, *only*
+  if that is necessary to fix non-trivial bugs, address serious performance
+  issues, or greatly enhance usability.  But please, do this sparsely and
+  rarely!
+
+* Major releases can introduce backward-incompatibilities (albeit such
+  incompatibilities should be announced well in advance, and a smooth
+  transition plan prepared for them), and try more risking and daring
+  refactorings and code cleanups.

 
 * For more information, refer to the extensive discussion associated
   with automake bug#13578.
 
 * For more information, refer to the extensive discussion associated
   with automake bug#13578.


@@ -145,30 +156,30 @@
   latest stable version of Autoconf installed and available early
   in your PATH.
 
   latest stable version of Autoconf installed and available early
   in your PATH.
 

-* The Automake git tree currently carries three basic branches: 'maint',
-  'master' and 'next'.
+* The Automake git tree currently carries three basic branches: 'micro',
+  'maint' and 'master'.

 
 

-* The 'maint' branch, reserved to changes that should go into the next
+* The 'micro' branch, reserved to changes that should go into the next

   micro release; so it will just see fixes for regressions, trivial
   bugs, or documentation issues, and no "active" development whatsoever.
   Since emergency regression-fixing or security releases could be cut
   from this branch at any time, it should always be kept in a releasable
   state.
 
   micro release; so it will just see fixes for regressions, trivial
   bugs, or documentation issues, and no "active" development whatsoever.
   Since emergency regression-fixing or security releases could be cut
   from this branch at any time, it should always be kept in a releasable
   state.
 

-* The 'master' branch is where the development of the next minor release
+* The 'maint' branch is where the development of the next minor release

   takes place.  It should be kept in a stable, almost-releasable state,
   to simplify testing and deploying of new minor version.  Note that
   this is not a hard rule, and such "stability" is not expected to be
   takes place.  It should be kept in a stable, almost-releasable state,
   to simplify testing and deploying of new minor version.  Note that
   this is not a hard rule, and such "stability" is not expected to be

-  absolute (emergency releases are cut from maint anyway).
+  absolute (emergency releases are cut from the 'micro' branch anyway).

 
 

-* The 'next' branch is reserved for the development of the next major
-  release.  Experimenting a little here is OK, but don't let the branch
-  grow too unstable; if you need to do exploratory programming
-  or over-arching change, you should use a dedicated topic branch, and
+* The 'master' branch is reserved for the development of the next major
+  release.  Experimenting a little is OK here, but don't let the branch
+  grow too unstable; if you need to do exploratory programming or
+  over-arching change, you should use a dedicated topic branch, and

   only merge that back once it is reasonably stable.
 
   only merge that back once it is reasonably stable.
 

-* The 'maint' branch should be kept regularly merged into the 'master'
-  branch, and the 'master' branch into the 'next' branch.  It is advisable
+* The 'micro' branch should be kept regularly merged into the 'maint'
+  branch, and the 'maint' branch into the 'master' branch.  It is advisable

   to merge only after a set of related commits have been applied, to avoid
   introducing too much noise in the history.
 
   to merge only after a set of related commits have been applied, to avoid
   introducing too much noise in the history.
 


@@ -176,12 +187,12 @@
   developments.  They should be based off of a common ancestor of all
   active branches to which the feature should or might be merged later.
 
   developments.  They should be based off of a common ancestor of all
   active branches to which the feature should or might be merged later.
 

-* After a new minor release is done, the 'master' branch is to be merged
-  into the 'maint' branch, and then a "new" 'master' branch created
+* After a new minor release is done, the 'maint' branch is to be merged
+  into the 'micro' branch, and then a "new" 'maint' branch created

   stemming from the resulting commit.
   stemming from the resulting commit.

-  Similarly, after a new major release is done, the 'next' branch is to
-  be merged into both the 'master' and 'maint' branch, and then "new"
-  'master' and 'next' branches created stemming from the resulting commit.
+  Similarly, after a new major release is done, the 'master' branch is to
+  be merged into both the 'micro' and 'maint' branches, and then "new"
+  'master' branch created stemming from the resulting commit.

 
 * When fixing a bug (especially a long-standing one), it may be useful
   to commit the fix to a new temporary branch based off the commit that
 
 * When fixing a bug (especially a long-standing one), it may be useful
   to commit the fix to a new temporary branch based off the commit that


@@ -189,14 +200,17 @@
   the active branches descending from the buggy commit.  This offers a
   simple way to fix the bug consistently and effectively.
 
   the active branches descending from the buggy commit.  This offers a
   simple way to fix the bug consistently and effectively.
 

-* For merges, prefer 'git merge --log' over plain 'git merge', so that
+* When merging, prefer 'git merge --log' over plain 'git merge', so that

   a later 'git log' gives an indication of which actual patches were
   merged even when they don't appear early in the list.
 
   a later 'git log' gives an indication of which actual patches were
   merged even when they don't appear early in the list.
 

-* The 'next', 'master' and 'maint' branches should not be rewound, i.e.,
+* The 'master', 'maint' and 'micro' branches should not be rewound, i.e.,

   should always fast-forward, except maybe for privacy issues.  For
   feature branches, the announcement for the branch should document
   the rewinding policy.
   should always fast-forward, except maybe for privacy issues.  For
   feature branches, the announcement for the branch should document
   the rewinding policy.

+  If a topic branch is expected to be rewound, it is good practice to put
+  it in the 'experimental/*' namespace; for example, a rewindable branch
+  dealing with Vala support could be named like "experimental/vala-work".

 
 ============================================================================
 = Writing a good commit message
 
 ============================================================================
 = Writing a good commit message


@@ -210,8 +224,9 @@
       <reference to relevant bugs, if any>
 
       Here goes a more detailed explanation of why the commit is needed,
       <reference to relevant bugs, if any>
 
       Here goes a more detailed explanation of why the commit is needed,

-      and a general overview of what it does, and how.  This section is
-      optional, but you are expected to provide it more often than not.
+      and a general overview of what it does, and how.  This section
+      should almost always be provided, possibly only with the expection
+      of obvious fixes or very trivial changes.

 
       And if the detailed explanation is quite long or detailed, you can
       want to break it in more paragraphs.
 
       And if the detailed explanation is quite long or detailed, you can
       want to break it in more paragraphs.


@@ -228,10 +243,10 @@
 
       <detailed list of touched files>
 
 
       <detailed list of touched files>
 

-* The <detailed list of touched files> is mandatory but for the most
-  trivial changes, and should follows the GNU guidelines for ChangeLog
-  entries (described explicitly in the GNU Coding Standards); it might
-  be something of this sort:
+* The <detailed list of touched files> should usually be provided (but
+  for short or trivial changes), and should follow the GNU guidelines
+  for ChangeLog entries (described explicitly in the GNU Coding
+  Standards); it might be something of this sort:

 
     * some/file (func1): Improved frobnication.
     (func2): Adjusted accordingly.
 
     * some/file (func1): Improved frobnication.
     (func2): Adjusted accordingly.


@@ -264,8 +279,6 @@
 
 * Use "make check" and "make maintainer-check" liberally.
 
 
 * Use "make check" and "make maintainer-check" liberally.
 

-* Make sure each test file is executable.
-

 * Export the 'keep_testdirs' environment variable to "yes" to keep
   test directories for successful tests also.
 
 * Export the 'keep_testdirs' environment variable to "yes" to keep
   test directories for successful tests also.
 


@@ -297,9 +310,14 @@
   The repository will always have its own "odd" number so we can easily
   distinguish net and repo versions.)
 
   The repository will always have its own "odd" number so we can easily
   distinguish net and repo versions.)
 

-* Run this:
+* Run these commands, in this order:

 
 

-    make bootstrap && make check && make distcheck
+    make bootstrap
+    make check keep_testdirs=yes
+    make maintainer-check
+    make distcheck
+    make check-no-trailing-backslash-in-recipes
+    make check-cc-no-c-o

 
   It is also advised to run "git clean -fdx" before invoking the
   bootstrap, to ensure a really clean rebuild.  However, it must
 
   It is also advised to run "git clean -fdx" before invoking the
   bootstrap, to ensure a really clean rebuild.  However, it must