IV19962: Incorrect output when using balanced or metronome GC policies

APAR status

• Closed as program error.

Error description

• Array data may be incorrectly processed when using the
  'balanced' or 'metronome' garbage collection policies. This may
  cause incorrect application behaviour such as incorrect output
  or unexpected exceptions.
  

Local fix

• The problem may be avoided by using a different garbage
  collector, or by disabling a specific optimisation with the
  command-line option
  
  -Xjit:disableBlockVersioner
  

Problem summary

• Problem may affect SRT and Balanced.
  It was introduced in Java7GA when switched to Hybrid arrays.
  Problem is in handling bndchkwithspinechk within VPhandler,
  causing the code to take a wrong path (believing it needs to
  take the exception).
  

Problem conclusion

• This defect will be fixed in:
  7.0.0 SR1
  6.0.1 SR2
  WRT-V3 SR1
  .
  Add necessary guard to make sure we are looking at the right
  value for the node when deciding on the path.
  

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:

  IV21493

Fix information

• Fixed component name

  JIT

• Fixed component ID

  620700124

Applicable component levels

• R260 PSY

     UP