Why do we emit vtables for abstract classes?

Mon Mar 13 14:31:00 GMT 2006

Tom Tromey writes:
 > >>>>> "David" == David Daney <ddaney@avtrex.com> writes:
 > 
 > David> I am looking at the assembly output of jc1 (recent svn trunk) and am
 > David> wondering why there are vtables for abstract classes.
 > 
 > David> There can never be an instance of an abstract class, so we should
 > David> never have to access its vtable.
 > 
 > David> Am I missing something, or is the vtable unneeded?
 > 
 > I have a vague memory that we changed to do this on purpose. And
 > there is a comment in link.cc about this... but all I can remember
 > right now is that we must lay out a vtable for an abstract class (so
 > that all the subclasses agree on the layout), not that we must
 > actually have the vtable available. (The layout info is available in
 > the 'methods' table.)
Yes; something to do with Miranda methods? We need the methods table,
but maybe not the vtable.
Andrew.