IJ21225: INFINITE LOOP ON STATIC FINAL FIELD MODIFICATION

APAR status

• Closed as program error.

Error description

• Error Message: The JVM will appear to hang. Repeated javacores
  will show the current active thread running code in the JIT DLL.
  .
  Stack Trace: The 'hung' thread that is in an infinite loop will
  have a backtrace similar to:
  TR::PatchMultipleNOPedGuardSites::compensate(TR_FrontEnd*, bool,
  void*) () from
  ./opt/ibm/java/jre/lib/amd64/compressedrefs/libj9jit29.so
  TR_RuntimeAssumptionTable::notifyIllegalStaticFinalFieldModifica
  tionEvent(TR_FrontEnd*, void*) () from
  ./opt/ibm/java/jre/lib/amd64/compressedrefs/libj9jit29.so
  jitIllegalFinalFieldModification () from
  ./opt/ibm/java/jre/lib/amd64/compressedrefs/libj9jit29.so
  .
  

Local fix

• -Xjit:disableStaticFinalFieldFolding Use of this option is
  likely to lower application performance - actual amount of
  affect is highly workload dependent but is often a few percent.
  

Problem summary

• A bug in the JIT logic to account for writes to static final
  fields can allow the handler code to enter an infinite loop. The
  code in question is called if a static final field has been
  examined when compiling a method and is subsequently modified by
  the application.
  

Problem conclusion

• The JIT logic for handling writes to static final fields has
  been updated to avoid the infinite loop.
  .
  This APAR will be fixed in the following Java Releases:
     8    SR6       (8.0.6.0)
  .
  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