IV01533: INCORRECT RESULTS FROM COMPILED METHODS

APAR status

• Closed as program error.

Error description

• Error Message: A Java program was seen to produce incorrect
  results from a method that performed string manipulation. The
  problem only occurred after the method had been compiled by the
  JIT.
  .
  Stack Trace: N/A
  .
  This is a very rare problem caused by incorrect optimisation of
  the code. It is possible that other behaviours such as GPF could
  be caused by this APAR.
  

Local fix

• The problem can be avoided by disabling the optimization that
  generates incorrect code. This can either be done globally or
  for the specific method that triggers the failure:
  -Xjit:disableLocalReordering
  or for a specific method:
  -Xjit:{packageA/packageB/ClassA.methodA(*}(disableLocalReorderin
  g)
  Disabling the optimization will have a negative impact on
  performance, however, if applied to a single method it is
  unlikely to be significant.
  

Problem summary

• The problem is caused when code is incorrectly optimized by the
  JIT.
  

Problem conclusion

• This defect will be fixed in:
  6.0.0 SR10
  .
  The JIT has been modified to remove the problem.
  .
  To obtain the fix:
  Install build 20110612 or later
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  PM41148

Fix information

• Fixed component name

  JIT

• Fixed component ID

  620700124

Applicable component levels

• R600 PSY

     UP