Can't use `is` type asserting function as predicate parameter

[timm-gs]

TypeScript Version: 2.5.3 and 2.7.0-dev.20171101

Code

type T1 = { t: 1 };
type T2 = { t: 2 };

function isT1(x: any): x is T1 {
    return x.t === 1;
}

function isT2(x: any): x is T2 {
    return x.t === 2;
}

function f(p: typeof isT1 | typeof isT2) {
    
} 

f(isT1);
f(isT2); // fails

Playground link

Expected behavior:
It compiles

Actual behavior:
Fails to compile:

Argument of type '(x: any) => x is T2' is not assignable to parameter of type '(x: any) => x is T1'.
  Type predicate 'x is T2' is not assignable to 'x is T1'.
    Type 'T2' is not assignable to type 'T1'.
      Types of property 't' are incompatible.
        Type '2' is not assignable to type '1'

Duplicate of #17757
Fixed by #17600

[typescript-bot]

Automatically closing this issue for housekeeping purposes. The issue labels indicate that it is unactionable at the moment or has already been addressed.