[LCG] Fix the bugs that Ben pointed out in code review (and the MSan bot
caught). Sad that we don't have warnings for these things, but bleh, no
idea how to fix that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206646 91177308-0d34-0410-b5e6-96231b3b80d8