java/1396: Compiler problem with LinkedList iterator

java/1396: Compiler problem with LinkedList iterator

[bryce]

>Number:         1396
>Category:       java
>Synopsis:       Compiler problem with LinkedList iterator
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    apbianco
>State:          closed
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Dec 20 12:19:35 PST 2000
>Closed-Date:    Wed Nov 22 22:05:03 PST 2000
>Last-Modified:  Wed Nov 22 22:16:00 PST 2000
>Originator:     Bryce McKinlay
>Release:        recent 2.97
>Organization:
>Environment:

>Description:
gcj apparantly miscompiles LinkedList.java.

The following test case will crash mysteriously:

import java.util.*;

public class LLTest
{
  public static void main(String[] args)
  {
    List l = new LinkedList();
    l.add("one");
    l.add("two");

    ListIterator i = l.listIterator();
    i.next();
    i.remove();
    System.out.println(i.next());
  }  
}

Program received signal SIGSEGV, Segmentation fault.
0x4014be6b in java.util.LinkedList.removeEntry (this=@8069289, e=@8069270)
    at ../../../libjava/java/util/LinkedList.java:133
warning: Source file is more recent than executable.

133                 e.previous.next = e.next;
Current language:  auto; currently java
(gdb) bt
#0  0x4014be6b in java.util.LinkedList.removeEntry (this=@8069289, e=@8069270)
    at ../../../libjava/java/util/LinkedList.java:133
#1  0x4014bae8 in java.util.LinkedList$LinkedListItr.remove (this=@8066ae0)
    at ../../../libjava/java/util/LinkedList.java:631
#2  0x804bb25 in LLTest.main (args=@4020ffc0) at LLTest.java:13
#3  0x400ee087 in gnu::gcj::runtime::FirstThread::run (this=@8067ea0)
    at ../../../libjava/gnu/gcj/runtime/natFirstThread.cc:146
#4  0x400f8df6 in java::lang::Thread::run_ (obj=@8067ea0)
    at ../../../libjava/java/lang/natThread.cc:263
#5  0x401aeb11 in really_start (x=@80bcff8)
    at ../../../libjava/posix-threads.cc:344
#6  0x402c8692 in GC_start_routine (arg=@8081fc0)
    at ../../../boehm-gc/linux_threads.c:631
#7  0x402e0b85 in pthread_start_thread (arg=@bf7ffe40) at manager.c:241

It appears that an incorrect "this" is passed to 
LinkedList.removeEntry() from LinkedListItr.remove(),
resulting in the wrong code to be executed inside that 
method.

This seems similar to the "Hashtable" bug, PR 332.
>How-To-Repeat:
Try to run the above test case on the latest libgcj
>Fix:

>Release-Note:

>Audit-Trail:

Formerly PR gcj/367

State-Changed-From-To: open->feedback
State-Changed-By: apbianco
State-Changed-When: Wed Nov 22 19:12:11 2000
State-Changed-Why:
    I attached a patch.

From: apbianco@cygnus.com
To: apbianco@cygnus.com, bryce@albatross.co.nz,
  java-gnats@sourceware.cygnus.com
Cc:  
Subject: Re: gcj/367
Date: 23 Nov 2000 03:12:11 -0000

 Synopsis: Compiler problem with LinkedList iterator
 
 State-Changed-From-To: open->feedback
 State-Changed-By: apbianco
 State-Changed-When: Wed Nov 22 19:12:11 2000
 State-Changed-Why:
     I attached a patch.
 
 http://sources.redhat.com/cgi-bin/gnatsweb.pl?cmd=view&pr=367&database=java

From: Bryce McKinlay <bryce@albatross.co.nz>
To: apbianco@cygnus.com
Cc: java-gnats@sourceware.cygnus.com
Subject: Re: gcj/367
Date: Thu, 23 Nov 2000 18:55:26 +1300

 apbianco@cygnus.com wrote:
 
 >  Synopsis: Compiler problem with LinkedList iterator
 
 Patch works nicely for me. Thanks!
 
 regards
 
   [ bryce ]
 
 
State-Changed-From-To: feedback->closed
State-Changed-By: apbianco
State-Changed-When: Wed Nov 22 22:05:03 2000
State-Changed-Why:
    I checked in this patch:
      http://gcc.gnu.org/ml/gcc-patches/2000-11/msg01335.html

From: apbianco@cygnus.com
To: apbianco@cygnus.com, bryce@albatross.co.nz,
  java-gnats@sourceware.cygnus.com
Cc:  
Subject: Re: gcj/367
Date: 23 Nov 2000 06:05:03 -0000

 Synopsis: Compiler problem with LinkedList iterator
 
 State-Changed-From-To: feedback->closed
 State-Changed-By: apbianco
 State-Changed-When: Wed Nov 22 22:05:03 2000
 State-Changed-Why:
     I checked in this patch:
       http://gcc.gnu.org/ml/gcc-patches/2000-11/msg01335.html
 
 http://sources.redhat.com/cgi-bin/gnatsweb.pl?cmd=view&pr=367&database=java

From: Alexandre Petit-Bianco <apbianco@cygnus.com>
To: Bryce McKinlay <bryce@albatross.co.nz>
Cc: java-gnats@sourceware.cygnus.com
Subject: Re: gcj/367
Date: Wed, 22 Nov 2000 22:06:36 -0800 (PST)

 Bryce McKinlay writes:
 >  Patch works nicely for me. Thanks!
 
 Cool, thanks. I checked in this patch and closed the PR:
 
   http://gcc.gnu.org/ml/gcc-patches/2000-11/msg01335.html
 
 Note that the patch is a bit different compared to what I originally
 sent to you. Updating parse.y might trigger conflicts.
 
 ./A
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