collect2 / ld giving strange errors with undefined virtual functions

[Martin v. Loewis]

> I'm not sure how the linker could figure out what is the method whose
> definition is missing.  Only if the vt mangling included the name of
> such method, which we could introduce in the new ABI.

That could be similar to the linker warning. If there is a section
.gnu.warning.SYMBOL, linking SYMBOL will result in printing the
message with the name __evoke_link_warning_SYMBOL.

Regards,
Martin