Remove 2 lang hooks, cleanup initialization of toplev.c

[Neil Booth]

I'd appreciate it if this patch were reviewed.

Thanks,

Neil.

Neil Booth wrote:-

> This patch removes two langhooks that are not part of langhooks.h -
> init_parse() and init_decl_processing().  They are folded into the
> "init" langhook from langhooks.h.  It also completely reorganizes
> initialization in toplev.c; breaking it down to a few logical areas
> like parsing options, language-independent initialization and
> language-dependent initialization.  There will be at least one
> follow-up to this, for cleanup and to document exactly what the
> initialization language hooks can assume, and what they are expected
> to initialize.
> 
> At the same time this fixes PR c/4053, the debug init / CPP init
> chicken and egg problem.  We now get the debug info correct if
> compiling a preprocessed file; this required some reorganization
> of initialization in cpplib too.
> 
> The toplev.c changes are very similar to what rth OK-ed a couple of
> days ago; I didn't apply them because things had changed in CVS and my
> local tree and I couldn't get that patch to bootstrap again.
> 
> This has bootstrapped x86 Linux for c, objc, c++, java and f77 without
> regressions.  OK to commit?
> 
> Neil.