Add [artificial] debug info annotation to test matching r171826

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@171830 91177308-0d34-0410-b5e6-96231b3b80d8
Don't warn about undefined varargs argument behavior in unreachable code.

Fixes <rdar://problem/12322000>.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@171831 91177308-0d34-0410-b5e6-96231b3b80d8
Add a test to make sure that vector output happens for debug info.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@171834 91177308-0d34-0410-b5e6-96231b3b80d8