https://issues.dlang.org/show_bug.cgi?id=12621

          Issue ID: 12621
           Summary: [Reg]: covariance no longer checked for function
                    overriding
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: regression
          Priority: P1
         Component: DMD
          Assignee: nobody@puremagic.com
          Reporter: bugzilla@digitalmars.com

class C15
{
    void foo() pure;
    void bar();
}

class D15 : C15
{
    override void foo();       // should issue a covariant error
    override void bar() pure;  // not an error - pure can override impure
}

dmd used to diagnose this correctly. Same issue with nothrow and @safe attributes.

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