IV81083: FAILURE TO UPDATE VARIABLE IN LOOP COPYING FROM BYTE ARRAY INTO CHARACTER ARRAY

APAR status

• Closed as program error.

Error description

• Error Message: N/A
  .
  Stack Trace: N/A
  .
  A loop copying from a byte array into a character array updates
  only
   one of the two integer variables that it is meant to
  update. Generally
   the result of this is inconsistent state after execution
  of the loop.
   One potential symptom is that the loop appears to exit
  prematurely.
   This only occurs on z Systems.
  

Local fix

• The issue can be worked around using
  -Xjit:disableIdiomRecognition, which
   may be restricted to a particular method. Note that this
  may impact
   performance.
  

Problem summary

• An optimization in the JIT compiler recognized the loop and
  transformed
   it into a specialized hardware instruction sequence, but
  omitted to
   update one of the variables modified by the original loop.
  

Problem conclusion

• The compiler has been modified so that it will no longer
  transform this
   particular form of recognized loop, which is rare.
  .
  This APAR will be fixed in the following Java Releases:
   7 SR9 FP40 (7.0.9.40)
   8 SR3 (8.0.3.0)
   6 SR16 FP25 (6.0.16.25)
   7 R1 SR3 FP40 (7.1.3.40)
   6 R1 SR8 FP25 (6.1.8.25)
  .
  Contact your IBM Product's Service Team for these Service
  Refreshes and Fix Packs.
  For those running stand-alone, information about the available
  Service Refreshes and Fix Packs can be found at:
   https://www.ibm.com/developerworks/java/jdk/
  

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:

  PI79842

• Fixed component name

  JIT

• Fixed component ID

  620700124

Applicable component levels

• R260 PSY

     UP

• R130 PSY

     UP

• R600 PSY

     UP