Description Olivier Thomann 2008-12-17 11:14:51 EST

With the following test case:
import java.util.List;
import java.util.ArrayList;
import java.util.Iterator;
public class X {
	public static void main(String[] args) {
		List l = new ArrayList();
		List l2 = new ArrayList();
		l.add(new X());
		for (Iterator iterator = l.iterator(); iterator.hasNext() ;) {
			l2.add(((X) iterator.next()).toString() 
				.substring(3));
		} 
		for (Iterator iterator = l2.iterator(); iterator.hasNext() ;) {
			System.out.println(iterator.next());
		} 
	}
	public String toString() {
		return "NO_SUCCESS";
	}
}

we produce the following code generation:
     36  astore_3 [iterator]
     37  goto 63
     40  aload_2 [l2]
     41  aload_3 [iterator]
     42  invokeinterface Iterator.next() : Object [30] [nargs: 1]
     47  checkcast X [1]
     50  invokevirtual X.toString() : String [36]
     53  iconst_3
     54  invokevirtual String.substring(int) : String [40]
     57  invokeinterface List.add(Object) : boolean [20] [nargs: 2]
     62  pop
     63  aload_3 [iterator]
     64  invokeinterface Iterator.hasNext() : boolean [46] [nargs: 1]

        [pc: 0, line: 6]
        [pc: 8, line: 7]
        [pc: 16, line: 8]
        [pc: 30, line: 9]
        [pc: 40, line: 10]
        [pc: 41, line: 11]
        [pc: 57, line: 10]
        [pc: 63, line: 9]
        [pc: 72, line: 13]
        [pc: 82, line: 14]
        [pc: 94, line: 13]
        [pc: 103, line: 16]

You can see that the entry for pc 41 is boggus. It doesn't correspond to the right line of code.
It should be:
        [pc: 40, line: 10]
        [pc: 53, line: 11]
        [pc: 57, line: 10]


This is causing some grief to the code to retrieve the right line of source for API/Tools (see bug 258950).

The problem comes from the last entry in the line number attribute that we add using the pc that starts the whole cascading method invocation. We should update the pc to the position that is located before we invoke the last method invocation.