[Bug c++/50243] vtable for pure abstract class (interface) shouldn't be emitted

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50243

--- Comment #4 from Jason Merrill <jason at gcc dot gnu.org> 2013-04-02 21:19:18 UTC ---
Created attachment 29782
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=29782
possible patch

The patches we checked in today for 34949 almost fix this bug as well, but not
quite; the vtable pointer assignment remains in the exception handler, because
optimize_clobbers in tree-eh.c is removing the clobber before it can be used to
optimize away the assignment.

This patch fixes that by skipping MEM_REF clobbers, but I suspect this isn't
really the right way to fix the issue.  Jakub?