introduced in r106343, but only showed up recently (with a particular compiler &
linker combination) because of the particular check, and because we have no
builtin checking for dereferencing the end of an array, which is truly
unfortunate.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106908 91177308-0d34-0410-b5e6-96231b3b80d8