Re: Roadmap beginnings

[Ian Lance Taylor <iant@google.com>]

Tom Tromey <tromey@redhat.com> writes:

> Tom> * Correct expression parsing.  (Though I am told this is extremely
> Tom> difficult to impossible in the general case.)
>
> Daniel> It does a not half bad job, and specific problems with it are fixable.
> Daniel> As for ultimate correctness and completeness, I have serious doubts
> Daniel> that it is feasible - and I also doubt it would see enough use to
> Daniel> justify the enormous investment.  Prove me wrong and we'll merge it :-)
>
> :).  I'm looking around a bit to see if I can find specifics of what
> is wrong.

I don't know if this counts as "expression parsing," but the most
obvious problems that I encounter are the difficulties in working with
STL objects.  Given "std::vector<T> v", I can't do "print v[0]".
Given "std::vector<T>::iterator p", I can't do "print *p".  That is
minimal required functionality for good C++ debugging.  This needs to
work smoothly for STL types and for user defined types.

It would also be nice if gdb could do template parameter defaulting,
although that is rather less important as tab completion can take care
of it.

A related problem, which I don't know how to solve, is that many
simple C++ accessors get inlined, and are not available when
debugging.  This makes it vastly more difficult to debug optimized C++
programs (indeed, this problem is more serious for me in practice than
the debuginfo problems discussed at the summit).

Ian