[PATCH] [ms-cxxabi] Elide dtor access checks for pass-by-val objects in callees

[Hans Wennborg]

  The problem is that MarkFunctionReferenced does access checks as it marks functions as referenced. This makes perfect sense, except here when we want to be able to call the dtor but bypass the access check.

  Richard: it would be interesting to hear your thoughts on this. Is the added plumbing of this boolean variable through the various functions an acceptable approach? Would it be ok to avoid that with some mechanism to "trap" access check errors (maybe a flag on Sema)? Or is it not worth the hassle to change this?

http://llvm-reviews.chandlerc.com/D2409