=== tests/cases/compiler/ambiguousOverloadResolution.ts ===
class A { }
>A : A

class B extends A { x: number; }
>B : B
>A : A
>x : number

declare function f(p: A, q: B): number;
>f : { (p: A, q: B): number; (p: B, q: A): string; }
>p : A
>A : A
>q : B
>B : B

declare function f(p: B, q: A): string;
>f : { (p: A, q: B): number; (p: B, q: A): string; }
>p : B
>B : B
>q : A
>A : A

var x: B;
>x : B
>B : B

var t: number = f(x, x); // Not an error
>t : number
>f(x, x) : number
>f : { (p: A, q: B): number; (p: B, q: A): string; }
>x : B
>x : B