Benjamin Kramer 8d3a1523dd [Support] Base RWMutex on std::shared_timed_mutex (C++14)
This should have the same semantics. We use std::shared_mutex instead on
MSVC and C++17, std::shared_timed_mutex is less efficient than our
custom implementation on Windows, std::shared_mutex should be faster.

llvm-svn: 369018
2019-08-15 16:55:23 +00:00
..