how to have alias this with an unaccessible member?

[Dicebot]

Btw, fun fact. This code crashes 2.063 beta:

------------------------

struct A(T)
{
     private T x;
     alias y = x;
     alias y this;
}

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dmd: aliasthis.c:114: virtual void AliasThis::semantic(Scope*): 
Assertion `t' failed.