distro-configs files, autogen.sh options, defaults etc

[Petr Mladek]

Stephan Bergmann píše v St 25. 04. 2012 v 21:20 +0200:
> On 04/25/2012 05:05 PM, Lubos Lunak wrote:
> >   The choice has already been made, and it's whatever we ship as our internal
> 
> ...more or less intensively patched...
> 
> > copies.
> 
> (At least, this was a real problem in the past, when people thought they 
> could replace LO's -- or, back then, OOo's rather -- copies with stock 
> instances, where the former often had specific fixes that either -- for 
> whatever reason -- where not upstreamed at all, or nobody had bothered 
> to actually do a proper version check for in configure.  I would hope 
> this has improved over time, though.)

Bjorn and Enrico speaks about some risks. I think that the main risk is
what Stephan wrote above. We should not prefer system libraries if the
internal copy has an important fix.

Well, how many internal libraries have an important fix? Just a quick
look and I see:

	+ libcdr: just build fixes
	+ libcmis: not sure about the virtual destructor patches
	+ libcroco: just makefile
	+ libexttextcat: just build fix
	+ libgsf: just build fix
	+ libpng: just build fix
	+ librsvg: just windows fixes
	+ libvisio: just build fixes
	+ libwpd: no patch
	+ libwpg: just build fixes
	+ libwps: just build fixes
	+ ...

You see that most system libraries should be safe to use. In addition,
distro specific packages has to use system libraries because it oreduces
maintenance effort, optimizes build and download size. So, the system
libraries are tested and should be tested. Why not use them during
development?

We already prefer some system libraries by default: e.g. glibc, libpng,
libjpeg? Where is the edge? Lubos just want to increase this group.

If you are afraid of uncertainity of what version is used. I see the
following scenarios:

1. distro builds:

	+ they need as many system libraries as possible

          => should use --with-system-libraries and explicitly enable
           only the internal libraries that are really needed from
           some reasons (use --without-system-<bla> for this)


2. official TDF release:

	+ need to use as many internal libraries as possible to be
          usable on different systems

          => we could solve it by adding --without-system-<bla> to
             distro-configs/*.conf; we have beta/rc phase to find bugs
             here


3. developer builds:
	+ they need all features to make sure that they do not break
          anything; they do not mind about system libraries; IMHO, the
          more system libraries, the less potential build problems and
          the faster build

        => they will be happy if configure takes systems libraries if
           they are available by default


If you are still in doubts, configure could print a summary of used
system/internal stuff and what it means. It might be useful in any case.


Regarding the --automagic option, IMHO, it is not really needed and it
would make things more complicated. It will be another mode that the
configure checks need to take care of. IMHO, developers want this by
default. Other groups use long list of configure options anyway.


Best Regards,
Petr