[PATCH] Add MicrosoftVFTableContext to AST

[Timur Iskhodzhanov]

2013/7/30 John McCall <rjmccall at apple.com>:
> How so?  Itanium’s v-tables are still logically broken up into separate
> components, such that an access through any one v-table pointer only
> ever accesses a particular component.

Yes

> You could very easily change
> Itanium to allocate all the v-tables in separate symbols without any need
> to change the code for virtual calls.  It’s just that Itanium is trying to
> optimize the number of separate symbols required.

Yes

But still it does affect the vcall mechanism in some sense - for
example, the covariant-return overrider might require you to use a
vbase's vptr to call a method defined in the derived object, which is
different from the Itanium ABI. Not sure if it belongs to that clause
though.