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Re: Extra RTTI flags in G++


Mark Mitchell wrote:
Does anyone know why we're putting extra bits into the flags word for
__vmi_class_type_info?  Like "non_public_base_mask" and
"public_base_mask"?

If our runtime actually depends on these flags being set, we're
broken; an ABI-compliant compiler needn't set them.  Even if we don't
depend on them (but do check for them), we're being unfriendly --
we're taking up bits that some future verison of the ABI might want.
the runtime doesn't use them. I must have forgotten to remove them
after experimenting with the ABI. I suppose it should be safe to
remove them. Their only documentation is the comment in cxxabi.h,
(which doesn't say 'gnu extension').
The cxxabi.h at the ABI site has them :( but 2.9.5/6(c) of the ABI
doc does not.

nathan

--
Nathan Sidwell    ::   http://www.codesourcery.com   ::     CodeSourcery LLC
         The voices in my head said this was stupid too
nathan@codesourcery.com : http://www.cs.bris.ac.uk/~nathan/ : nathan@acm.org



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