IV82442: CRASH IN JITINSTANCEOF DURING THE DEREFERENCE OF AN UNLOADED CLA SS
Closed as program error.
Error Message: A segmentation error is thrown when the compiled code tries to dereference a class reference whose value is invalid because the class it refers to has been unloaded. . Stack Trace: Unhandled exception Type=Segmentation error vmState=0x00040000 J9Generic_Signal_Number=00000004 ExceptionCode=c0000005 ExceptionAddress=6EEFAEC2 ContextFlags=0001003f Handler1=6F3CF230 Handler2=6F388520 InaccessibleReadAddress=00000010 EDI=236DD900 ESI=00000000 EAX=251ABF00 EBX=236DD900 ECX=00000000 EDX=236DD900 EIP=6EEFAEC2 ESP=23FCC6D0 EBP=23079400 EFLAGS=00010206 GS=002B FS=0053 ES=002B DS=002B Module=j9jit28.dll Module_base_address=6E970000 Offset_in_DLL=0058aec2 Target=2_90_20160206_289328 (Windows 8.1 6.3 build 9600) CPU=x86 (2 logical CPUs) (0xfff8d000 RAM) ----------- Stack Backtrace ----------- jitInstanceOf+0x82 (nathelp.asm:4228, 0x6EEFAEC2 <OSB>j9jit28+0x58aec2<CSB>) (0x237D3DDF) (0x251ABF00) (0x224D8D68) (0x2307EC78) .
This issue can be worked around using the -Xjit:disableLoopVersioner option globally or on the affected methods. Note however that this workaround is likely to have a noticeable negative performance impact, especially when used globally.
In some circumstances the JIT may generate an instanceof test as part of rearranging program code to improve performance. Under some rare circumstances this instanceof test can fail unexpectedly due to class unloading - the JIT moves the instanceof beyond the guards protecting it from this event. This invalid state can result in a program crash or in very rare circumstances an incorrect result being computed.
The JIT compiler has been updated to ensure that the motion of instanceofs correctly accounts for potential class unloading during compiled method execution. . This APAR will be fixed in the following Java Releases: 8 SR3 (126.96.36.199) 7 SR9 FP40 (188.8.131.52) 6 R1 SR8 FP25 (184.108.40.206) 6 SR16 FP25 (220.127.116.11) . 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/
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NoSpecatt / Xsystem
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APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
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