Bug: tsc crash TypeError: Cannot read property 'flags' of undefined

[purificant]

TypeScript Version: 2.9.2 and typescript@next at the time of writing.

Search Terms: TypeError: Cannot read property 'flags' of undefined

Code

class Abstract {
  protected constructor() {
  }
}

class Concrete extends Abstract {
}

type Constructor<T = {}> = new (...args: any[]) => T;

function Mixin<TBase extends Constructor>(Base: TBase) {
  return class extends Base {
  };
}

class Empty {
}

class CrashTrigger extends Mixin(Empty) {
  public trigger() {
    new Concrete();
  }
}

Example repo with code to reproduce: https://github.com/purificant/typescript-crash-example

Expected behavior:
tsc emits an error along the lines of "TS2674: Constructor of class 'Abstract' is protected and only accessible within the class declaration."

Actual behavior:
tsc crashes with the following stack trace:

typescript-crash-example/node_modules/typescript/lib/tsc.js:63860
                throw e;
                ^

TypeError: Cannot read property 'flags' of undefined
    at getBaseTypes (typescript-crash-example/node_modules/typescript/lib/tsc.js:25683:38)
    at isConstructorAccessible (typescript-crash-example/node_modules/typescript/lib/tsc.js:36070:37)
    at resolveNewExpression (typescript-crash-example/node_modules/typescript/lib/tsc.js:36024:22)
    at resolveSignature (typescript-crash-example/node_modules/typescript/lib/tsc.js:36180:28)
    at getResolvedSignature (typescript-crash-example/node_modules/typescript/lib/tsc.js:36209:26)
    at checkCallExpression (typescript-crash-example/node_modules/typescript/lib/tsc.js:36282:29)
    at checkExpressionWorker (typescript-crash-example/node_modules/typescript/lib/tsc.js:37687:28)
    at checkExpression (typescript-crash-example/node_modules/typescript/lib/tsc.js:37629:42)
    at checkExpressionStatement (typescript-crash-example/node_modules/typescript/lib/tsc.js:39545:13)
    at checkSourceElement (typescript-crash-example/node_modules/typescript/lib/tsc.js:41180:28)