C++ ABI: Proposed key function tweak

[Mark Mitchell]

>>>>> "Jason" == Jason Merrill <jason at redhat.com> writes:

    Jason> OK, I concede.  But how would you feel about making this
    Jason> change for other targets in g++?  I'm thinking particularly
    Jason> of those that don't have a COMDAT mechanism.

If you think that's really valuable, maybe.  

But, I'm not convinced that the marginal benefit here will outweigh
the cost of having subtly different ABIs in different places.  Right
now, we're in a situation where things are very consistent across
platforms; arguable more so than with the old ABI.

I'd still argue that to help the non-COMDAT people there are two good
approaches:

  - A prelinker that puts everything together nicely.

  - Wait: they'll all go away with a few years.
   
    Even PowerPC AIX may get a COMDAT-like thing according to David
    Edelsohn.

I guess the questions is whether people use pure virtual destructors
enough to make this worthwhile?

--
Mark Mitchell                   mark at codesourcery.com
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