Try to guess when the auto-generated cl::Sink option should be marked 'extern'.

This would be much easier to do if the CommandLine library didn't use
global state. Global state is evil.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60659 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed