APAR status
Closed as program error.
Error description
Error Message: A SIGSEGV/GPF is received . Stack Trace: Java stack from javacore Java callstack: at java/lang/J9VMInternals.fastIdentityHashCode(J9VMInternals.java: 360(Compiled Code)) at java/lang/Object.hashCode(Object.java:119(Compiled Code)) . This problem was introduced in Java 8.0.5.22 and fixed in Java 8.0.5.35. It effects all platforms.
Local fix
This issue can be worked around using the -Xjit:disableUnsafe option. Note however that this may have performance impact.
Problem summary
The JIT may query the constant pool entry twice to decide what intermediate representation to use for a call. During the two queries, the state of the constant pool entry may change from unresolved to resolved, causing a mismatch in information the JIT gets from the two queries, which then results in an unexpected intermediate representation that can be transformed into bad machine code.
Problem conclusion
The JIT has been updated to re-read all the information from constant pool entry if the entry is resolved at the second query. . This APAR will be fixed in the following Java Releases: 8 SR5 FP35 (8.0.5.35) . 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
IJ19897
Reported component name
JIT
Reported component ID
620700124
Reported release
130
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2019-09-26
Closed date
2019-10-02
Last modified date
2019-10-02
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
[{"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:
02 October 2019