[Bug sanitizer/64670] -fsanitize=vptr leads to "undefined reference to `typeinfo for class'"

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64670

--- Comment #12 from Jason Merrill <jason at gcc dot gnu.org> ---
(In reply to Tobias Burnus from comment #11)
> Because log.o has due to the vptr sanitizer:
>                  U typeinfo for LogListener

And why isn't that reference satisfied by the definition in LogListener.o?