[OpenMP] Remove shutdown attempt on Windows process detach

Only attempt shutdown if lpReserved is NULL. The Windows documentation
states:
When handling DLL_PROCESS_DETACH, a DLL should free resources such as
heap memory only if the DLL is being unloaded dynamically (the
lpReserved parameter is NULL). If the process is terminating (the
lpReserved parameter is non-NULL), all threads in the process except the
current thread either have exited already or have been explicitly
terminated by a call to the ExitProcess function, which might leave some
process resources such as heaps in an inconsistent state. In this case,
it is not safe for the DLL to clean up the resources. Instead, the DLL
should allow the operating system to reclaim the memory.

Differential Revision: https://reviews.llvm.org/D96750

0 files changed, 0 insertions, 0 deletions