https://bugs.winehq.org/show_bug.cgi?id=45453
--- Comment #5 from Juha Lepola fluxie@kapsi.fi --- Ok, so the actual variable that controls the format of "thread_siblings" is the number of CPUs Linux kernel is compiled to support. I had my mine set to 64. Once I changed that to 32, Guild Wars 2 started to work without any other changes.
I don't know the default value distributions are generally using so I cannot say how severe this issue actually is. The current implementation in "create_logical_proc_info" could reasonably support up to 64 logical processors. The limiting factor after that is that it cannot report multiple processor groups. https://docs.microsoft.com/en-us/windows/desktop/ProcThread/processor-groups