Re: Problems with bringing mozilla's configury up to date

[Christopher Seawood]

Philipp Thomas wrote:

> I'm trying to adapt Mozilla's autoconf stuff to current autoconf in order to
> be able to make configure regenerable and adaptable. Now mozilla does things
> in its own special way.

I'm not sure how using autoconf 2.13 makes Mozilla's configure less 
regenerable or less adaptable but to get it to work with autoconf 2.5x 
will probably require a major rewrite/butchering of the current script 
(which is not necessarily a bad thing).

Mozilla's initial problems with autoconf 2.5x have already been outlined 
at http://bugzilla.mozilla.org/show_bug.cgi?id=104642 .

The major known problems are as follows:

IIRC, the MOZ_TOPSRCDIR define needs to be moved into the toplevel 
configure.in script so that it's not processed before AC_INIT is called.

Autoconf 2.5x requires that macros only be called once which screws up 
the cross-compiling checks and some other conditional library checks. 
When building a specific version of the browser (say against gtk2), we 
don't want to check for unneeded libraries (like gtk1 or qt).  I still 
don't understand why conditional checks are frowned upon especially when 
some of them (like AC_PROG_CXX) will stop the script if they fail.

There appears to be no mechanism in autoconf 2.5x to allow extra 
arguments to be passed down to sub-configures.  This is needed for 
Mozilla as several of the libraries in cvs are released as standalone 
libraries and we need to pass options down from the toplevel configure 
to configure those sub-builds to suit the browser build.  It's not worth 
further forking those sub-projects just to change their default build 
configuration.  We exploit some exposed internal autoconf 2.13 variables 
& functions to get that hack to work.

The toplevel Mozilla configure script contains a hack to generate a 
mozilla-config.h header from any AC_DEFINEs which were called durinng 
configure.  (Yes, there should have been a mozilla-config.h.in file, 
don't get me started.)  Recently, that hack was hacked to allow modules 
to have their own individual module-config.h headers.

I think that should be all of the major gotchas.

- cls