[Issue 23969] Windows cannot export/import TLS from DLLs

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=23969

--- Comment #4 from Walter Bright <bugzilla at digitalmars.com> ---
Microsoft VC will not compile:

    __declspec(dllexport) __declspec(thread) int x = 3;

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