Re: Emacs contributions, C and Lisp

[David Engster <deng@randomsample.de>]

Richard Stallman writes:
>   > > My hope is that we can work out a kind of "detailed output" that is
>   > > enough for what Emacs wants, but not enough for misuse of GCC front ends.
>
>   > Anyone can write a GCC plugin that simply outputs the AST in some
>   > form.
>
> We are not talking about the same thing.  What I have in mind is to
> output considerably LESS than the AST -- just enough to do the
> completion and other operations that Emacs needs, and NO MORE.

I understand that. What I'm saying is: For almost five years now (since
gcc 4.5 introduced plugins), access to GCC's AST is wide open for
everyone. However, in all that time (and to my knowledge) no one has
used that to feed non-free backends, and that is in my opinion enough
evidence that your worries are unfounded. They might have been valid in
the past, but not since LLVM and clang have joined the scene.

> To figure out just what Emacs needs, that's the task I am talking
> about.

If you want to support things like completions, refactoring, symbol
searches, etc., we need full access to the AST from inside Emacs.

>
>   >   Instead, is there anyone here who would
>   > > like to work on this in detail?
>
>   > I'm already working on it.
>
> Are you working on outputting just the data that Emacs needs for
> completion?

Completion is only the starting point. If that works, I hope more stuff
will follow. In any case, I will need the full AST. If you are saying
that you won't allow that, then this is a non-starter. Dealing with
GCC's AST is hard enough already; if I have to additionally worry what
information I'm allowed to feed to Emacs, than I'll simply stop working
on this.

-David