newlib build machinery

[Ralf Wildenhues <Ralf dot Wildenhues at gmx dot de>]

Hello,

I'm ploughing through src in order to update its autotools usage;
first thing I'm trying is whether current rebuild rules work and
things are in decent shape.

For now, I see the following issues in the newlib tree:

1) newlib.hin is apparently written manually, but still, with
--enable-maintainer-mode, rebuild rules are in place to invoke
autoheader (which then fails due to missing templates).  Which
is the desirable mode of operation, autoheader or manual generation
of the file?  In the latter case, the rebuild rule should be deactivated
to avoid accidental trigger of the wrong rule.

2) The newlib tree already uses differing versions of autoconf and
automake for various of its files.  Is that all by accident or was it a
conscious decision?

3) The macros from toplevel src/config/ are not used, esp. override.m4,
which is crucial in allowing a smooth upgrade and working around bugs in
Autoconf.  Is that not-use a conscious decision, and if yes, are there
reasons to keep it that way (e.g., a need to build independently of the
src/ tree), and if yes, which way should I go?
I think minimally, override.m4 needs to be included, since you seem to
already have confsubdir.m4 in place (hey, I added that! :-).

Thanks,
Ralf