Add r184420 back, but also handle long file names.

Original message:

Don't include directory names in archives.

This matches the behavior of both gnu and os x versions of ar.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184423 91177308-0d34-0410-b5e6-96231b3b80d8
5 files changed