IJ12157: INCORRECT NULL POINTER EXCEPTION THROWN

APAR status

• Closed as program error.

Error description

• Error Message: java.lang.NullPointerException is incorrectly
  thrown from a program point that should not be able to observe a
  null value. The issue only occurs on X86.
  .
  Stack Trace: N/A.
  .
  The issue only occurs on the x86 platform when running Java 8SR5
  FP21 to FP26 (8.0.5.21 through 8.0.5.26) inclusive.
  

Local fix

• The problem can be circumvented with
  -Xjit:disableInlineCheckcast. This may have a minor impact on
  throughput performance.
  

Problem summary

• The x86 code generator can fail to correctly generate an
  implicit NULLCHK sequence when evaluating a checkcastAndNULLCHK
  opcode. The failure to run the NULLCHK allows a null value to be
  observed at a point in the program where it is unexpected.
  

Problem conclusion

• The JVM has been updated to correct apply null-check before
  checkcast again an interface.
  .
  This APAR will be fixed in the following Java Releases:
     8    SR5 FP27  (8.0.5.27)
  .
  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:

Fix information

• Fixed component name

  JIT

• Fixed component ID

  620700124

Applicable component levels