Name: rmT116609 Date: 02/12/2003


FULL PRODUCT VERSION :
# java -version
java version "1.4.1_01"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.1_01-b01)
Java HotSpot(TM) Client VM (build 1.4.1_01-b01, mixed mode)

FULL OPERATING SYSTEM VERSION :
Linux 2.4.18-24.7.x i686

Additional Operating Systems: Solaris 2.8

DESCRIPTION OF THE PROBLEM :
If you disassemble class files with javap from 1.4.x you will sometimes get "null" as the receiver of invocations and field operations. This is a bug in that version of javap. If you use jdk-sun-1.3.1 it works just fine. The bug seems to have infested IBM, SUN and blackdown's JDK 1.4.x.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1. javap -c java.util.Vector | grep null

EXPECTED VERSUS ACTUAL BEHAVIOR :
Actual result (you can guess what I'd expect):
javap -c java.util.Vector | grep null
   2 getfield #26 <Field null>
   7 putfield #26 <Field null>
   2 getfield #27 <Field null>
   7 putfield #27 <Field null>
   2 getfield #29 <Field null>
   7 putfield #29 <Field null>
  36 aconst_null
   1 ifnonnull 34
  15 ifnonnull 20
  43 ifnonnull 72
  57 ifnonnull 62
   2 getfield #43 <Field null>
   7 putfield #43 <Field null>
 112 aconst_null
   2 getfield #45 <Field null>
   7 putfield #45 <Field null>
   2 getfield #47 <Field null>
   7 putfield #47 <Field null>
   2 getfield #48 <Field null>
   7 putfield #48 <Field null>
   2 getfield #51 <Field null>
   7 putfield #51 <Field null>
  20 aconst_null
  38 putfield #54 <Field null>
  55 aconst_null
   2 getfield #62 <Field null>
   7 putfield #62 <Field null>
   2 getfield #65 <Field null>
   7 putfield #65 <Field null>
  78 aconst_null
   2 invokespecial #67 <Method null>
   2 getfield #68 <Field null>
   7 putfield #68 <Field null>
   2 invokespecial #71 <Method null>
   2 invokespecial #72 <Method null>
   2 getfield #73 <Field null>
   7 putfield #73 <Field null>
   1 invokespecial #76 <Method null>
   2 getfield #79 <Field null>
   7 putfield #79 <Field null>


With JDK1.3.1_07:
------------------
java version "1.3.1_07"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.1_07-b02)
Java HotSpot(TM) Client VM (build 1.3.1_07-b02, mixed mode)
cindercone:/home/ranjithm/tmpjava 46 % javap -c java.util.Vector | grep null
  36 aconst_null
   1 ifnonnull 34
  15 ifnonnull 20
  43 ifnonnull 72
  57 ifnonnull 62
 112 aconst_null
  10 aconst_null
  55 aconst_null
  78 aconst_null
  59 aconst_null


REPRODUCIBILITY :
This bug can be reproduced always.

CUSTOMER WORKAROUND :
Switch to C and use gdb.

Release Regression From : 1.3.1_07
The above release value was the last known release where this
bug was known to work. Since then there has been a regression.

(Review ID: 181152)
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