purify experiments

[Jason Merrill]

>>>>> Jason Merrill <jason@cygnus.com> writes:

> OK, never mind again.  I fixed the obstacks that weren't being freed, and
> that saved an entire 16 bytes out of 13 megs.

I fixed it better, and it now saves about a meg (in both egcs and devo).

> Which is the other interesting point: devo gcc (from the internal Cygnus
> sources) takes 13 megs to compile your smaller testcase, while egcs takes
> 41 megs (both with -O -fno-exceptions).  The C++ frontend is identical,
> so it must be a backend problem.

Each of the inline maybepermanent_obstacks seems to take up a lot more
space with egcs:

inline obstacks: 199 obstacks, 21738336 bytes

vs.

inline obstacks: 199 obstacks, 3430016 bytes

That's quite a difference.  Hmm....

Jason