Only the first of Class.Layout.VTablePointers on Itanium is used

[ddobrev]

Many classes in our tests have multiple v-table pointers in their layout on Itanium. However, we only use the first one. An example is MissingObjectOnVirtualCall in CSharp. There might be a bug in the parser which fill the v-tables incorrectly, or a bug in our logic which disregards the remaining pointers but shouldn't. We should dump the v-table layout with Clang and read the documentation on Itanium because we might have a dangerous bug in the generated code.

[ddobrev]

https://eli.thegreenplace.net/2012/12/17/dumping-a-c-objects-memory-layout-with-clang/ should help.