https://issues.dlang.org/show_bug.cgi?id=16453

          Issue ID: 16453
           Summary: Missing @nogc annotations
           Product: D
           Version: D2
          Hardware: All
               URL: http://dlang.org/
                OS: All
            Status: NEW
          Severity: major
          Priority: P3
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: eyal@weka.io

core.thread functions are not marked @nogc

For example: thread_isMainThread

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