Linux vs. libio

[Jeffrey A Law]

  In message < u9g0wxbk5g.fsf@yorick.cygnus.com >you write:
  > >>>>> Jeffrey A Law <law@cygnus.com> writes:
  > 
  >  > You will need to work with the glibc folks to find a solution that makes
  >  > sense to them as we do not want to start changing the API of the libio
  >  > contained in GCC without making corresponding changes to the libio
  >  > contained in glibc.
  > 
  > The problem is that part of the libio API is the C++ vtables, so any ABI
  > change that modifies the layout of the vtable (such as -fvtable-thunks) or
  > how the vtable is found breaks libio. 
Right.  This is precisely why I stated that we should not change libio without
changing glibc too.  They need to change in lock-step.

That means that the libc folks have to be intimately involved in the decisions
we make regarding the ABI/API of libio (and IMHO have the ultimate yea/nay
decision for such changes).

  > This has caused us a lot of trouble over the years; perhaps the answer is
  > to change that design,
Possibly, but that does not help us with the existing glibc installations.

  > but this *is* supposed to be the all-singing, all-dancing, ultimate C++
  > ABI.
:-)  I'll be floating on air when it's all ready.  I really want to put
the ABI issues behind us once and for all.



jeff