Construction vtables

[Jason Merrill]

>>>>> Martin von Loewis <loewis at informatik.hu-berlin.de> writes:

 >> Doesn't the ABI spec call for complete object ctor/dtors which would
 >> create the VTT and subobject ctors/dtors that recieve the VTT in their
 >> argument list?

 > What do you mean by 'create'? Dynamically, at run-time? I hope not.
 > The VTTs should be emitted statically according to some rule (probably
 > together with the vtables), and would get a certain external mangled
 > name. Also, constructors and destructors in classes with VTTs would
 > have a second implicit parameter (after this), which is the VTT
 > pointer.

 > My question is what the calling convention for destructors is.

I think Colleen answered that question; see issues C-5 and C-6.  The
in-charge [cd]tors would not have a VTT parm; the not-in-charge versions
would.

 > The alternative is that the caller passes the right VTT always, which
 > means that there need to be two destructor entry points in case of
 > virtual destructors.

Which there already are (well, three, actually).

Jason