The full list of resolved issues in 1.9.1 is available here.
AspectJ has updated to a recent JDT compiler version (commit #abe06abe4ce1 - 9-Apr-2018). With this update it now supports Java10. This means you can use the 'var' support. A simple example of combining var with an aspect:
public class Code3 {
	public static void main(String []argv) {
		var x = "hello";
		System.out.println(x.getClass());
	}
}
aspect X {
	before(): call(* *.getClass()) && target(String) {
		System.out.println(thisJoinPointStaticPart);
	}
}
Available: 1.9.1 available 20-Apr-2018