https://issues.dlang.org/show_bug.cgi?id=23180

          Issue ID: 23180
           Summary: annotate @gshared declarations with @weak on OSX
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Mac OS X
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: bugzilla@digitalmars.com

See explanation here:

https://github.com/dlang/dmd/pull/14208

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