[Issue 20838] on modern (x86_64) CPUs, dmd emit cmpxchg8b instead of CMPXCHG16B

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=20838

--- Comment #12 from kinke <kinke at gmx.net> ---
(In reply to mw from comment #11)
> Can you try if you can reproduce this segfault on a local Linux box?

We're abusing DMD's bug tracker, but anyway: you need to manually take care of
required 16-bytes alignment:

align(16) shared(N) n; // or `align(2 * size_t.sizeof)`

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