Re: Options --enable{,-no}-install-program

[Jim Meyering]

Stepan Kasal <address@hidden> wrote:

Hi Stepan!

Happy new year :)

> Karel has pointed me to the new options of coreutils' configure:
>   --enable-install-program=PROG_LIST
>                           install the programs in PROG_LIST (comma-separated,
>                           default: none)
>   --enable-no-install-program=PROG_LIST
>                           do NOT install the programs in PROG_LIST
>                           (comma-separated, default: arch hostname su)
>
> A few comments:
>
> 0) I would call it --ena...-programs, i.e., with plural at the end,
> as it seems to match the meaning better.

Yes, that sounds better.

> 1) --enable-no-install-program ... default: arch hostname su
>
> No, this is not the default value of this option.  The dafault value
> would have to use commas, not spaces, as separators.  More
> importantly, if this were the default value, then
>   --enable-no-install-program=hostname,su
> would be a slight modification of the default, so it would behave
> almost as the default, with the only difference that "arch" is
> installed.  This is not what your code does.
>
> "arch hostname su" is the set of programs which are not installed by
> default.  It should be documented somewhere, but it may be outside
> ./configure --help.

Yes.  I fixed that last year :-)
  http://git.sv.gnu.org/gitweb/?p=coreutils.git;a=commitdiff;h=c3cac089b1e6cc5c

> 2) The set of programs that are not installed by default is specified
> on two places: configure.ac and src/Makefile.am.  configure checks
> that the two match, each time a user builds coreutils..
>
> I cannot agree with this.  I believe the solution is to have one
> primary source definig the set.  There are several ways to achieve
> that:
>
> 2a) src/Makefile.am might be the primary source.  configure.ac would
> contains something like:
>
> m4_include(excluded.m4)
> gl_INCLUDE_EXCLUDE_PROG([optional_bin_progs], EXCLUDED_BY_DEFAULT)
>
> while excluded.m4 would contain:
>
> m4_define([EXCLUDED_BY_DEFAULT], [arch hostname su])
>
> excluded.m4 would be generated from src/Makefile.am, by a rule
> declared in Makefile.am

Doesn't this create a chicken and egg problem?
You'd need to run configure before you can use Make, yet
you'd need to include a make-generated file in creating configure.

> 2b) Vice versa: configure.ac would be the primary source, and
> src/Makefile.am would contain:
>       include $(top_srcdir)/excluded.am
> which would be generated from configure.ac by a rule in Makefile.am

Remember that Automake (run before make and configure) needs to know
the list of all buildable programs.  The configure option selects which
are _installed_.

> 2c) It should also be possible to create a separate file,
> excluded.magic, which would get included by both configure.ac and
> src/Makefile.am.  It would be a bit tricky, though.
>
> I could write a patch for 2), but I think that the answer to 1) might
> make it irrelevant, so I'm not rushing in...

It'd be great to remove the current kludge.

If you're really motivated, there's another minor problem:
the include/exclude mechanism operates only on bin_PROGRAMS,
and not bin_SCRIPTS.  That means --enable-no-install-program=groups
doesn't work, since "groups" is a script.