gp := getg()

	isOK := func(gp1 *g) bool {
		// Checking isSystemGoroutine here makes GoroutineProfile
		// consistent with both NumGoroutine and Stack.
		return gp1 != gp && readgstatus(gp1) != _Gdead && !isSystemGoroutine(gp1, false)
	}

	pcbuf := makeProfStack() // see saveg() for explanation
	stw := stopTheWorld(stwGoroutineProfile)