https://issues.dlang.org/show_bug.cgi?id=20899

          Issue ID: 20899
           Summary: Qualifiers on alias parameters inconsistency between
                    built-in types and user defined types
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: major
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: john.loughran.colvin@gmail.com

template X(alias A) {
    alias X = A;
}

struct S {}

pragma(msg, X!(const(int))); // const(int)
pragma(msg, X!(const(S))); // S

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