https://issues.dlang.org/show_bug.cgi?id=14601

          Issue ID: 14601
           Summary: pthread functions aren't marked @nogc
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Windows
            Status: NEW
          Severity: blocker
          Priority: P1
         Component: druntime
          Assignee: nobody@puremagic.com
          Reporter: aliloko@gmail.com

https://github.com/D-Programming-Language/druntime/blob/e66f03494a13c7ce13bbe4c260ce689682af865e/src/core/sys/posix/pthread.d#L26

That makes it impossible to build any sort of @nogc nothrow synchronization.

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