This patch addresses the following issue:

* RSP-27180 64-bit builds crash with threads
Creating and using a thread (eg std::thread) could result in an access violation on some machines.

This was caused by an error setting up the Win64 32-byte shadow space inside the code to clean up TLS (thread-local storage) data, combined with the compiler applying a tail-call optimization to a method call within that cleanup code, which used that space. The patch correctly sets up the shadow space, and the crash with TLS no longer occurs.