V8 (and probably others) now has some special cases for async functions (and generators, I think, but those are much more rare) to show useful stack traces with the lineage of async calls. For example, this code shows the stack trace you'd expect when run in latest Chrome or Node.js.

  async function c() { throw new Error('Some error'); }
  async function b() { await c(); }
  async function a() { await b(); }
  a();