Properly handle multiple nonnull attributes in CodeGen

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@216638 91177308-0d34-0410-b5e6-96231b3b80d8
[modules] Number anonymous declarations that are lexically within mergeable
contexts, so that we can merge them when we merge the surrounding context.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@216639 91177308-0d34-0410-b5e6-96231b3b80d8