https://issues.dlang.org/show_bug.cgi?id=13581

          Issue ID: 13581
           Summary: disallow NaN as AA key value
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P2
         Component: druntime
          Assignee: nobody@puremagic.com
          Reporter: code@dawg.eu

There should be a runtime check in the AA code that prevents from using floating point NaN as key value, as this value doesn't compare equal to itself.

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