PATCH: Reguire __cxa_atexit for ext/{new, throw}_allocator/deallocate_global.cc

[Benjamin Kosnik]

> >   Shouldn't this be xfailed on solaris, rather than skipped on all
> > non-cxa_atexit targets?
> 
> no, this way lies madness ;-(  I'm strongly opposed to added any
> target-based xfails or skips if there's a general feature that can be
> tested for. 

Thank you. Agreed 100%.

>  A
> prominent example (which I'll attack soon) is the large list of
> different target lists used to decide if the target has pthread
> support.  This is both inconsistent and a nightmare to maintain, e.g.
> if adding a new target.

Hallelujah. Thank you for tackling this, it is most apprecaited. This is
already a nightmare to maintain and was never intended to last as long
as it has.

(And as an aside, I think for solaris -pthread (no s) no works so can
be massively simplified anyway.)

-benjamin