APAR status
Closed as program error.
Error description
Error Message: Various error messages are possible, including no error message. A known one is an unexpected ArrayIndexOutOfBounds Exception. . Stack Trace: IBM XML Java code is known to trigger the problem in the following methods: com/ibm/xml/.../SimplePositionHelper.getCurrentPosition10 and, com/ibm/xml/.../DataBufferHelper.computeCoords10 .
Local fix
The problem can be worked around by either globally disabling the loop unrolling optimization with the following Java option: -Xjit:disableGLU Or, the loop unrolling optimization can be disabled on specific methods that are experiencing the problems. Note that if those methods get inlined into other methods then the optimization will not be disabled on the inlined methods. Disabling inlining of the methods can be done with the following Java option: -Xjit:dontInline={package/Class.method(signature)} Please note that any of these workarounds can affect performance.
Problem summary
The problem is caused by the loop unrolling optimization not detecting an exit condition in the outer loop of a nested loop with a depth of 2. As a result the unrolled version of the loop will have copies which do not have the exit condition and thus the loop may not terminate as expected.
Problem conclusion
The JIT compiler has been updated to correctly handle nested loops which have unique features like the ones which exposed the problem in this APAR. . This APAR will be fixed in the following Java Releases: 7 R1 SR3 FP20 (7.1.3.20) 6 R1 SR8 FP15 (6.1.8.15) 8 SR2 (8.0.2.0) 7 SR9 FP20 (7.0.9.20) . 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 number
IV77908
Reported component name
JIT
Reported component ID
620700124
Reported release
130
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2015-10-09
Closed date
2015-10-09
Last modified date
2015-10-15
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
PI50631
Fix information
Fixed component name
JIT
Fixed component ID
620700124
Applicable component levels
R130 PSY
UP
R260 PSY
UP
[{"Business Unit":{"code":"BU048","label":"IBM Software"},"Product":{"code":"SSC9HBA","label":"Just In Time (JIT) Compiler"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"130","Edition":"","Line of Business":{"code":"","label":""}}]
Document Information
Modified date:
15 October 2015