scan aclocal.m4

[platform/upstream/automake.git] / TODO

Priorities for release:
!! documentation (eg new macros)
!! finish up TAGS work
* `acinstall'
* echo in installs?
* `missing' program
* copyrights on m4 files, aclocal output

For now I guess I'll just have automake give an error if it encounters
non-C source in a libtool library specification.


* must split $obj into two parts: one for libtool and one for
  deansification.  Otherwise .S files will be deansified!

* look @ jim's $(t:=foo) problem

* should install-foo target for a new dir (eg fooexecdir) be run via
  install-data or install-exec?  Consider examining name of variable.

* compatibility with older versions of autoconf if not --gnu

================================================================

* CONFIG_HEADER is passed incorrectly in ":" mode.

* put parser.h into distribution if "yacc -d" is used

* only remove libtool at top level?

* clean up source directory by moving stuff into subdirs

* consider adding pkglibexecdir, maybe others?
  requests for pkg-dirs with version included

Fix ansi2knr so that knr-style function decls aren't incorrectly
rewritten.  Or, fix automake so that not all sources in a directory
must be ansi.  Should also fix things so that a separate ._o file is
not needed; instead use a wrapper script.

Gord on pretty-printing instead of raw loops:
Gord> I think the best thing to do is to have make output be a valid shell
Gord> script, and to have it be clear exactly what is happening at a given
Gord> time.


Further:
- man page fixes
- consider adding "echo"s to installs again.
  users can use make SHELL='sh -x' to get the full dirt

Avoid loops when installing; instead unroll them in automake

* for new autoconf:
  * completely handle multi-":" mode for AC_CONFIG_HEADER
  * Scan multiple input files when Makefile is generated?
    This would provide flexibility for large projects; subsumes
    the "Makefile.tmpl" idea

   [ can't do this.  must explain why in manual.
     basically, solving all the problems is too hard
     like: how to remove redundancies between generated .in files
     instead should implement `include' directive for Makefile.am ]
* for multi-":" mode and AC_OUTPUT, it might be good to pick the
  first input file that has a corresponding .am file.

Some long-term projects:
* if $(FOO) is used somewhere, ensure FOO is defined, either by
  user or by automake if possible
* Don't rearrange order of `include' lines relative to += assignments.
* Handle += assignments at all.

consider putting all check-* targets onto @check?
To support --help/--version checking?

take diff-n-query code from libit

Per Bothner says:
Per> 1) Being able to build a set of non-source programs
Per> from source programs, without necessarily linking them together.
Per> I.e. one should be able to say something like:
Per>    dummy_SOURCES=foo.c bar.c
Per> and automake should realize that it needs to build foo.o and bar.o.
Per> 2) Being intelligent about new kinds of suffixes.
Per> If it sees:
Per>    SUFFIXES = .class .java
Per> and a suffix rule of the form:
Per>    .java.class:
Per> then it should be able to realize it can build .class files from
Per> .java files, and thus be able to generate a list of
Per> .class files from a list of .java source files.

From Jason Molenda:
* allow a way to use "gzip --best"
   [ Try  GZIP=--best make dist ]
* don't assume GNU tar is "tar" (eg in distcheck)

* actually use acinstall program

!! Must fix require_file stuff.  It is really gross, and I don't
   understand it any more.

* error messages should print ``[info blah blah]'' command when a
  certain part of the standards apply.  saw idea in message from
  Craig Burley.  wouldn't it be really cool if compile-mode in Emacs
  understood this convention, and you could click on such text to
  go to the appropriate info page?

!! should write autoconf-style doc entries for each m4 macro

Jim's idea: should look for @setfilename and warn if filenames too long
* guess split size
* allow ".info" to be missing

* must update GNU Hello

** many requests for a way to omit a file from the distribution.
   Should be done like `!foo' or `~foo' in _SOURCES, etc.
   Such files should be removed explicitly after the copy step!
   Doing this requires rewriting macros before generating Makefile.in.

from joerg-martin schwarz:
 -- If Makefile.am contains $(CC), $(COMPILE), $(YLWRAP), .... 
    in an explicitly written rule,  you should emit the corresponding
    Makefile variables automatically.

Configuring in the large:
* allow hierarchy of dirs to share one aclocal.m4
  How?

consider printing full file name of Makefile.am or configure.in when
giving error.  This would help for very large trees with many
configure.in scripts

From the GNU Standards.  These things could be checked, and probably
should be if --gnu.
*    Make sure that the directory into which the distribution unpacks (as
well as any subdirectories) are all world-writable (octal mode 777).
*   Make sure that no file name in the distribution is more than 14
characters long.
*    Don't include any symbolic links in the distribution itself.
     (ditto hard links)
*    Make sure that all the files in the distribution are world-readable.
** also, check --help output and --version output.  Idea from François
* standards no longer prohibit ANSI C.  What does this imply
  for the de-ansi-fication feature?

consider supporting "var+= stuff" syntax.  rewrite to just var=... on
output.  This is sometimes convenient when you want to write a
Makefile.am in more-or-less modular parts

should be able to determine what is built by looking at rules (and
configure.in).  Then built man pages (eg) could automatically be
omitted from the distribution.

Idea from Joerg-Martin Schwarz: allow passing different -D flags to
different compiles.  This can be done, but with the restriction that a
.c cannot appear in 2 different "objects" (programs/libraries)
compiled with different -D options (because -c and -o do not always
work together and parallel makes must work).  This could be
implemented by noticing whenever a ".o" target with no rules is being
emitted, and adding the appropriate compilation rule as appropriate.
This should work with targets from Makefile.am as well as from .P
files, which means rewriting so that the Makefile.am contents aren't
copied into the output immediately.  This feature is probably required
to fully support libtool ("grody compilation issue")
 [ this could be probably done more directly by examining the sources
   as we scan Makefile.am ]

Henrik Frystyk Nielsen says:
Henrik> 4) Flags like --include-deps are lost when you make changes to
Henrik> Makefile.am files and automake is run automatically. It would
Henrik> be nice to keep these flags as I now have to redo everything
Henrik> manually.
... what about other options here too?

Think about: maybe "make check" should just bomb if error occurs?
Then user must use "make -k check".  This is probably more natural.

Consider: "cvs" option adds some cvs-specific rules?

Right now, targets generated internally (eg "install") are not
overridable by user code.  This should probably be possible, even
though it isn't very important.  This could be done by generating all
internal rules via a function call instead of just appending to
$output_rules.
 [ this will be harder to implement when scanning a rule like all-recursive
   from subdirs.am ]

* Should be a way to have "nobuild_PROGRAMS" which aren't even built,
  but which could be by running the magic make command.

Other priorities:
* Must rewrite am_install_var.  Should break into multiple functions.
  This will allow the callers to be a little smarter.
* Rewrite clean targets.
* Must rewrite error handling code.  Right now it is a real mess
  Should fix up require_file junk at the same time

Things to finish libtool support:
* Handle grody compilation issue
  Namely: some objects require a different compilation rule
* Handle install changes
* Handle clean changes
* New definition for LINK

djm wants ``LINKS'' variable; list of things to link together after
install.  In BSD environment, use:
        LINKS = from1 to1 from2 to2 ...

Need way to say there are no suffixes in a Makefile (Franc,ois'
"override" idea suffices here)

Check to make sure various scripts are executable (IE when looking for
them in a directory)

Use recode in dist target when MAINT_CHARSET specified.  Read caveats
in automake.in before doing this.  Note the same problem used to apply
to the no-dependencies option; maybe it still should?  Note also that
each Makefile.am must be rewritten at "make dist" time if
MAINT_CHARSET and DIST_CHARSET are not identical.  NOTE: gettext must
arrange for all .po files not to be recoded.  In the long term this
might be a problem (consider when some systems use Unicode but the
rest do not)
  MAINT_CHARSET *must* be local to each Makefile.am, to enable
        merged distributions.
  DIST_CHARSET must be passed down to subdir makes during a "make dist"

Handle dist-zoo.  Generally add more DOS support.  Maybe run "doschk"
(why isn't this merged with "pathchk"?) when doing a dist.  Do
whatever else François says here...

Add support for html via an option.  Use texi2html.  Use
"html_TEXINFOS", and htmldir = .../html.  Include html files in
distribution.  Also allow "html_DATA", for raw .html files.
  [ when will texinfo directly support html? ]

uninstall and pkg-dirs should rm -rf the dir.

a potential bug: configure puts "blah.o" into LIBOBJS, thus implying
these files can't be de-ansified.  Not a problem?
  [ fix by using ansi2knr wrapper program ]

In general most .am files should be merged into automake.  For
instance all the "clean" targets could be merged by keeping lists of
things to be removed.  This would be a lot nicer looking.  Note that
the install targets probably should not be merged; it is sometimes
useful to only install a small part.

Clean up the output:
* Order rules sensibly
* Ensure every line has a purpose.  Omit unused stuff
* Eliminate extraneous rules when possible (eg 'install-am' stuff)
* Make sure vertical spacing is correct
Omit program transform vars from header if no program installed.  This
is currently pretty hard to do.  (But with beautification code it
would probably be easy)

Lex, yacc support:
* It would be nice to automatically support using bison's better features
  to rename the output files.  This requires autoconf support
* Consider supporting syntax from autoconf "derived:source", eg:
        y.tab.c:perly.y
  for yacc and lex source
* allow generating c++ source from lex?  Eg using flex?

Multi-language support:
* should have mapping of file extensions to languages
* should automatically handle the linking issue (special-case C++)
* must get compile rules for various languages; FORTRAN probably
  most important unimplemented language
This should be integrated in some way with Per's idea.
Eg .f.o rules should be recognized & auto-handled in _SOURCES
That way any random language can be treated with C/C++ on a first-class
basis (maybe)

It might be cool to generate .texi dependencies by grepping for
@include.  (If done, it should be done the same way C dependencies are
done)

It would be good to check some parts of GNU standards.  Already check
for install-sh and mkinstalldirs.  What else is required to be in
package by GNU standards or by automake?
Some things for --strictness=gnits:
* "cd $(foo); something" is an error in a rule.  Should be:
  "cd $(foo) && something"
* Look for 'ln -s' and warn about using $(LN) and AC_PROG_LN_S
* Look for $(LN) and require AC_PROG_LN_S

Auto-distribute "ChangeLog.[0-9]+"?  "ChangeLog.[a-z]+"?

Internationalize. [ gettext doesn't have the necessary machinery yet ]
am_error should use printf-style arguments (for eventual gettext scheme)

François says the ordering of files in a distribution should be as follows:
* README
* source files
* derived files
I agree, but I don't see how to implement this yet.
It might be easier if "derived files" is limited to those that
Automake itself knows about, eg output of yacc.

Check all source files to make sure that FSF address is up-to-date.
--gnits or --gnu only.

Merge each -vars.am file with corresponding ".am" file.  Can do this
because of changes to &file_contents.

Should libexec programs have the name transform done on them?

Order the output rules sensibly, so FOO_SOURCES and FOO_OBJECTS are
together and rules are in the usual order.

Make the output minimal: only output definitions for variables that
are used.

Look at dist's jmake for ideas.  dist is the name of the distribution
including Metaconfig.  Perl uses it.

Should handle directory hierarchies deeper than 2.  Right now there is
some support for this.  Here are some of the issues:
* Should handle AC_CONFIG_SUBDIRS, ie must handle configure.in in subdirs
    * can do this by looking at subdirs, seeing configure.in
      and auto-running Automake there

. Consider supporting guile-style PLUGIN directories automatically?

djm says:
David> To avoid comments like the one about subdirs getting buried in
David> the middle of a Makefile.in, how about pushing comments that
David> start with ### to the top of the Makefile.in (in order)?  Sort
David> of like how Autoconf uses diversions to force initialization
David> code to the top of configure.

Karl Berry says:
Karl> 2) Your Makefile variable names are generally uppercase, but GNU
Karl> generally uses lowercase. Not that it matters :-).

================================================================

Stuff for aclocal:

probably should put each group of m4 files into a subdir owned by the
containing application.

================================================================

Document:

multi-":" mode in AC_OUTPUT -- automake only looks at the first file
    also a note on how a .am file is found in this case

rationale for avoiding
        make CFLAGS="$CFLAGS" ...
in subdirs make rule

a package that installs its own aclocal macros

write example of using automake with dejagnu
follow calc example in dejagnu docs

document which variables are actually scanned and which are not.

Document customary ordering of Makefile.am.  From François.

Should include extended version of diagram from Autoconf (suggested by
Greg Woods)

Make a definition of the term "source"

document how to use Automake with CVS.  Idea from Mark Galassi.  Also
include Greg Woods' more sophisticated "cvs-dist" target.

document rebuilding configure.  CONFIGURE_DEPENDENCIES

_DEPENDENCIES -vs- _LIBADD/_LDADD; the tradeoffs

-- must document all variables that are supposed
   to be public knowledge

automake must be run in each directory with a configure.in
This is insufficiently clear

must document the targets required for integration with
non-automake-using subdirs

use of (eg) EXTRA_PROGRAMS is not very clear right now

document EXTRA_foo_SOURCES

document why EXTRA_* vars must be statically knowable

document the "make SHELL='/bin/sh -x'" trick for debugging

section on relationship to GNU make

LDFLAGS; maybe why it is different from LIBADD/LDADD

document that dependencies:
* are put into .deps
* are system-dependent

add a concept index

================================================================

Things to do for autoconf:

* patch autoreconf to run automake and aclocal.  I've done this but it is
  not really available.  It can't be made available until automake
  is officially released

================================================================

Libraries:

* Should support standalone library along with subdir library in same
  Makefile.am.  Maybe: turn off "standalone" mode if library's Makefile.am
  is not only one specd? [ add an option for this ]

================================================================

Longer term:

Would it be useful to integrate in some way with the Debian package
building utility?  Must check.  maybe it would be possible to deal
with all the different package utilities somehow.  Lately I've been
hearing good things about the RedHat packaging utilities.  Why are
there so many of these?  Are they fun to write or something?
The RedHat package utility is called RPM; see
        ftp://ftp.redhat.com/pub/code/rpm
It actually has problems, like no configure script and no documentation.

For Cygnus it would probably be good to be able to handle the native
package utility on each platform.  There are probably 3 or 4 of these
(sysv, solaris?, aix?)

tcl/unix/Makefile.in has some code to generate a Solaris package.

Automake probably can't do all of this on its own.  A new tool might
be a better idea

================================================================

A tool to guess what the local Makefile.am should look like:
(see Gord's Maint program!)

* Probably integrate with autoscan
* Use various simple rules to determine what to do:
  * get name of top directory, sans version info
  * search for .c files with 'main' in them
    * if in main.c, use directory name for program
    * if in more than one, generate multiple programs
    * if not found, generate a library named after directory
  * order subdir searches correctly: lib first, src last
  * assume 'testsuite' dir means we are using dejagnu
* maybe be smart about reading existing Makefile.am, so tool
  can be run for incremental changes?  You could imagine:

        Makefile.am:
                autoproject --incremental

================================================================

Stuff NOT to do, and why:

consider auto-including any file that matches "*.in".
  [ no: po/Makefile.in shouldn't be included ]

must look at mkid to see how it works (for subdir usage)
  [ right now, it doesn't.  i don't see a simple fix right now ]

if configure.in not found, move up a directory and try again?  This
could eliminate a common source of problems.
  [ this is just a bad idea ]

* scripts are installed in $exec_prefix/bin, not $prefix/bin
  Bug or feature?
  [ the consensus on Gnits is that this isn't required.
    doubters can work around it anyway ]

* make the auto-dep code crash if GNU make not in use?
  (doesn't it already?)

Looked at a program called 'ezmake', which seems to do something
similar.  The only idea there that is possibly worth stealing is using
globs in definitions.  Also has negations.  Eg in a directory with
files a.c, b.c and c.c, the line:
        foo_SOURCES = *.c ~c.c
would be equivalent to:
        foo_SOURCES = a.c b.c
Is this worth implementing?
  [ No... it is more reliable to spell everything out. ]

Scan source directories and warn about missing files, eg .c/.h files
that aren't mentioned?
  [ distcheck makes this less useful ]