[Issue 6607] critical_.d and critical.c use double check locking the wrong way

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=6607

--- Comment #5 from github-bugzilla at puremagic.com ---
Commit pushed to stable at https://github.com/D-Programming-Language/druntime

https://github.com/D-Programming-Language/druntime/commit/0b41a6205361382930272813a5f6a2baae0c456a
cleanup and rewrite rt.critical_

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