[PATCH] Add a thread-safe version of RefCountedBase

[Argyrios Kyrtzidis]

LGTM!

On Mar 3, 2014, at 5:49 PM, Ben Langmuir <blangmuir at apple.com> wrote:

> This patch adds a variant of RefCountedBase that uses a std::atomic_int to store the  reference count.  This class will be used by vfs::FileSystem in Clang so that the ref count won’t prevent vfs::FileSystem from ever being thread safe.
> 
> 
> <threadsaferefcountedbase.patch>