APAR status
Closed as program error.
Error description
Error Message: Incorrect output or unexpected behaviour possibly resulting in an unexpected exception being thrown or a crash. . Stack Trace: N/A . On the x86 and POWER platforms, only Java 7R1 and Java 8 are affected. On z Systems all releases mentioned below are affected.
Local fix
The issue can be avoided using the following Java option: -Xjit:disableIdiomRecognition or, if available, -Xjit:disableIdiomPatterns={CopyingTROx(*)} These options may have some performance impact, but they can be restricted to the problematic method to limit that if necessary.
Problem summary
The JIT compiler may try to optimize loops which read from a byte array and write to a char array. If this is optimization is performed, then incorrect results can be produced in one of the following ways: - If the loop should produce as output the sign-extension of each input byte, the output produced might instead be the zero-extension. - If the loop should add an offset to each value, the output produced might not include the offset. - On x86 and POWER platforms, if the loop should exit early for some byte values but not others, the loop might exit too early.
Problem conclusion
The JIT compiler has been updated to prevent the scenarios mentioned above from occurring. . This APAR will be fixed in the following Java Releases: 7 R1 SR4 (7.1.4.0) 8 SR4 (8.0.3.22) 6 SR16 FP40 (6.0.16.40) 6 R1 SR8 FP40 (6.1.8.40) 7 SR10 (7.0.10.0) . 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 number
IV91275
Reported component name
JIT
Reported component ID
620700124
Reported release
130
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2016-12-05
Closed date
2016-12-05
Last modified date
2017-02-02
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
R130 PSY
UP
R600 PSY
UP
R260 PSY
UP
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Document Information
Modified date:
02 February 2017