https://issues.dlang.org/show_bug.cgi?id=21706

          Issue ID: 21706
           Summary: Assertion failure in Base64.decoder for empty input
                    range of ranges
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: bugzilla@bernis-buecher.de

Same like issue 21679, but with decoder...

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