=== tests/cases/compiler/subtypingTransitivity.ts ===
class B {
>B : Symbol(B, Decl(subtypingTransitivity.ts, 0, 0))

    x: Object;
>x : Symbol(x, Decl(subtypingTransitivity.ts, 0, 9))
>Object : Symbol(Object, Decl(lib.d.ts, 92, 1), Decl(lib.d.ts, 223, 11))
}

class D extends B {
>D : Symbol(D, Decl(subtypingTransitivity.ts, 2, 1))
>B : Symbol(B, Decl(subtypingTransitivity.ts, 0, 0))

    public x: string;
>x : Symbol(x, Decl(subtypingTransitivity.ts, 4, 19))
}
class D2 extends B {
>D2 : Symbol(D2, Decl(subtypingTransitivity.ts, 6, 1))
>B : Symbol(B, Decl(subtypingTransitivity.ts, 0, 0))

    public x: number;
>x : Symbol(x, Decl(subtypingTransitivity.ts, 7, 20))
}

var b: B;
>b : Symbol(b, Decl(subtypingTransitivity.ts, 11, 3))
>B : Symbol(B, Decl(subtypingTransitivity.ts, 0, 0))

var d: D;
>d : Symbol(d, Decl(subtypingTransitivity.ts, 12, 3))
>D : Symbol(D, Decl(subtypingTransitivity.ts, 2, 1))

var d2: D2;
>d2 : Symbol(d2, Decl(subtypingTransitivity.ts, 13, 3))
>D2 : Symbol(D2, Decl(subtypingTransitivity.ts, 6, 1))

d.x = '';
>d.x : Symbol(D.x, Decl(subtypingTransitivity.ts, 4, 19))
>d : Symbol(d, Decl(subtypingTransitivity.ts, 12, 3))
>x : Symbol(D.x, Decl(subtypingTransitivity.ts, 4, 19))

b = d;
>b : Symbol(b, Decl(subtypingTransitivity.ts, 11, 3))
>d : Symbol(d, Decl(subtypingTransitivity.ts, 12, 3))

b.x = 1; // assigned number to string
>b.x : Symbol(B.x, Decl(subtypingTransitivity.ts, 0, 9))
>b : Symbol(b, Decl(subtypingTransitivity.ts, 11, 3))
>x : Symbol(B.x, Decl(subtypingTransitivity.ts, 0, 9))