Re: llvm & RTTI over shared libraries

From: Joerg Sonnenberger <>
Date: Wed, 27 Apr 2022 22:13:37 UTC
Am Tue, Apr 26, 2022 at 05:48:00PM -0700 schrieb Mark Millard:
> 	• Joerg Sonnenberger <> wrote on
> 	• Date: Tue, 26 Apr 2022 23:47:23 UTC :
> > Am Mon, Apr 25, 2022 at 03:39:48PM -0700 schrieb Mark Millard:
> > > Basically I avoid inline definitions of:
> > > 
> > > virtual ~type_base();
> > > virtual ~type_int();
> > > virtual ~type_string();
> > 
> > You only need to ensure that the class has one non-pure non-inline
> > function.
> I'm confused at what you are claiming that I did wrong or
> described incorrectly for the example at hand.

I'm giving the exact rule to make sure the OP knows what exactly to
follow. Otherwise they can test a chance, discover that in their use
case an inlined dtor actually works because something else is the key
function etc. I don't disagree with your example, I just want to make
sure that it is understood what the critical point is.

> > If there is no such function, both will be defined as weak
> > mergable symbol and that will not result in a unique address when using
> I was certainly less detailed about how multiple definitions
> are handled. Was that your point?

I added that note because it also tells you what symptoms to look for to
diagnose the issue. E.g. it is normally a bad sign in C++ to see weak
vtable and type symbols and something that should be checked.