https://issues.dlang.org/show_bug.cgi?id=13458

          Issue ID: 13458
           Summary: std.utf.decode not @nogc
           Product: D
           Version: D2
          Hardware: All
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: Phobos
          Assignee: nobody@puremagic.com
          Reporter: rburners@gmail.com

https://issues.dlang.org/show_bug.cgi?id=13429 this one is blocked by std.utf.decode not being nogc.

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