https://issues.dlang.org/show_bug.cgi?id=20106

          Issue ID: 20106
           Summary: core.atomic : atomicFence doesn't accept MemoryOrder
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: druntime
          Assignee: nobody@puremagic.com
          Reporter: turkeyman@gmail.com

Not sure why this function doesn't accept a MemoryOrder, but that's basically its job.

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