linux-packaging-mono/mcs/errors/cs1986-2.cs

// CS1986: The `await' operand type `int' must have suitable GetAwaiter method
// Line: 15

static class S
{
	public static void GetAwaiter (this int i)
	{
	}
}

class A
{
	static async void Test ()
	{
		await 1;
	}
}