https://issues.dlang.org/show_bug.cgi?id=20107

          Issue ID: 20107
           Summary: core.atomic : Memory order is missing keys
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: druntime
          Assignee: nobody@puremagic.com
          Reporter: turkeyman@gmail.com

MemoryOrder is missing acq_rel and consume.
Even if DMD can't make use of these; LDC and GDC can.

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