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Date: Sat, 23 Apr 2022 23:33:04 +0200
From: Joerg Sonnenberger <joerg@bec.de>
To: freebsd-hackers@freebsd.org
Subject: Re: llvm & RTTI over shared libraries
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Am Tue, Apr 19, 2022 at 11:03:33PM -0700 schrieb Mark Millard:
> Joerg Sonnenberger <joerg_at_bec.de> wrote on
> Tue, 19 Apr 2022 21:49:44 UTC :
> 
> > Am Thu, Apr 14, 2022 at 04:36:24PM +0000 schrieb jbo@insane.engineer:
> >> > After some research I seem to understand that the way that RTTI is handled over shared library boundaries is different between GCC and LLVM.
> >> 
> > I think you are running into the old problem that GCC thinks comparing
> > types by name makes sense where as everyone else compares types by type
> > pointer identity.
> 
> Seems out of date for the GCC information . . .
> 
> https://gcc.gnu.org/faq.html#dso reports:
> 
> QUOTE
> The new C++ ABI in the GCC 3.0 series uses address comparisons, rather than string compares, to determine type equality.
> END QUOTE

Compare that with the implementation in <typeinfo>.

Joerg