Tsan false positive with Arc

[vors]

Hello!

I tried a simple example with Arc with calling drop from 2 different threads and tsan reports a race on it https://gist.github.com/vors/83d78aa5e4b0cc0f730f54d99eafd692 .
Is it because it ignores the atomic::fence or for some other reason?
The implementation is pretty much rewrite in rust of this boost example: https://www.boost.org/doc/libs/1_55_0/doc/html/atomic/usage_examples.html#boost_atomic.usage_examples.example_reference_counters

[Kestrer]

This is fixed now in Rust itself.