Re: Putting C++ code into gcc front end

[Geoff Keating <geoffk at geoffk dot org>]

> Date: Fri, 7 Mar 2003 22:20:21 +0000
> From: Neil Booth <neil at daikokuya dot co dot uk>

> It would be much easier if you didn't have to worry about 6 different
> front ends for every dinky little change you make to some tree.  Or
> if you had something that documented the quirks of how every field was
> used by every front end.  We have nothing close to that.  It's almost
> impossible to make significant changes to trees: not only do they
> represent everything, but they represent everything in every goddamn
> front end.  It's a really nasty situation to be in.
> 
> Every front end should have it's own representation, which should be
> lowered to something common like GIMPLE that is simple, well-
> documented, and yet expressive enough to be useful to everyone.  I
> feel we can't make real progress any other way.  Imagine how
> maintainable each front-end having its own high-level IR with real
> distinct C structs and unions would be.

Well... When I tried to imagine, I started thinking "and, yes, we
could have completely different representations for exceptions and
structures and references and function calls between the C, C++, Ada,
and Java frontends" which didn't sound quite so great.  After all,
another project which is also a good idea and not making much progress
recently is to commonize more of the C and C++ frontends.

Maybe a better solution would be to document what the tree structure
is actually supposed to look like, and then try to ensure that?

-- 
- Geoffrey Keating <geoffk at geoffk dot org>