[Bug java/23230] New: Wrong "this" used when call made to superclass which is also superclass of enclosing class

greenrd at greenrd dot org gcc-bugzilla@gcc.gnu.org
Thu Aug 4 15:01:00 GMT 2005


The following file is miscompiled by gcj -C:

public class Outer extends Thread {

  public class Inner extends Thread {
    private Inner () {
      start ();
    }
  }

}

It uses the wrong "this" to call start():

Outer$Inner(Outer);
  Code:
   0:   aload_0
   1:   aload_1
   2:   putfield        #12; //Field this$0:LOuter;
   5:   aload_0
   6:   invokespecial   #15; //Method java/lang/Thread."<init>":()V
   9:   aload_1
   10:  invokevirtual   #18; //Method java/lang/Thread.start:()V
   13:  return

}

Sun's compiler outputs correct code:

private Outer$Inner(Outer);
  Code:
   0:   aload_0
   1:   aload_1
   2:   putfield        #1; //Field this$0:LOuter;
   5:   aload_0
   6:   invokespecial   #2; //Method java/lang/Thread."<init>":()V
   9:   aload_0
   10:  invokevirtual   #3; //Method start:()V
   13:  return

}

The difference is at 9.

Note: The bug does not occur if you just replace start() (which is declared in
java.lang.Thread) with notify() (which is declared in java.lang.Object).

-- 
           Summary: Wrong "this" used when call made to superclass which is
                    also superclass of enclosing class
           Product: gcc
           Version: 4.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: java
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: greenrd at greenrd dot org
                CC: gcc-bugs at gcc dot gnu dot org,java-prs at gcc dot gnu
                    dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23230



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