egcs and glibc

[H.J. Lu]

>From what I can see so far, the recent change to glibc 2.1 will
cause much trouble for libio in egcs on Linux. I'd like to see
the new glibc 2.1 supported in egcs soon. I have some ideas to
fix it. But it will introduce some overhead and shared libstd++
compiled with glibc 2.0 won't be compatible with the one compiled
with new glibc 2.1.

I can start working on it now. But I don't want to duplicate
the effort.

Basically I will add new fields in _IO_FILE and use the "_unused"
field to compute the "vtable" address. I think it should work
with both glibc and iostream. Let's me know what you think.


-- 
H.J. Lu (hjl@gnu.ai.mit.edu)