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IV29908: MISALIGNED STACK OBJECT GC ASSERT

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APAR status

  • Closed as program error.

Error description

  • Error Message: B392CA00: Misaligned object in thread Pooled
    Thread #48 running
    org.apache.harmony.sound.tests.javax.sound.midi.MetaMessageTest
    j> 10:12:13 B392CA00: O-Slot=B35FA18C
    j> 10:12:13 B392CA00: O-Slot value=B70F8FAB
    j> 10:12:13 B392CA00: PC=AFD8FFC6
    j> 10:12:13 B392CA00: framesWalked=1
    j> 10:12:13 B392CA00: arg0EA=B392C794
    j> 10:12:13 B392CA00: walkSP=B392C69C
    j> 10:12:13 B392CA00: literals=00000000
    j> 10:12:13 B392CA00: jitInfo=AE577718
    j> 10:12:13 B392CA00: method=0997C104
    (org/apache/harmony/sound/tests/javax/sound/midi/MetaMessageTest
    .test_constructor_MetaMessage()V) (JIT)
    j> 10:12:13 B392CA00: stack=B392AD18-B392C908
    j> 10:12:13 09:12:13.619 0x8e60a00    j9mm.479    *   **
    ASSERTION FAILED ** at MarkingScheme.cpp:1165:
    ((MM_StackSlotValidator(0, object, stackLocation,
    walkState).validate(_env)))
    .
    Stack Trace: N/A
    .
    

Local fix

  • -Xjit:disableLocalReordering would work around this problem;
    this turns off a JIT optimization that should not affect
    performance noticeably
    

Problem summary

  • The problem is caused when a pointer into the middle of a Java
    array (an internal pointer) is not updated by the GC because of
    a bug in a JIT compiler optimization.
    

Problem conclusion

  • This defect will be fixed in:
    7.0.0 SR3
    6.0.1 SR4
    6.0.0 SR12
    5.0.0 SR15
    .
    The JIT compiler has been updated to prevent the problem from
    occurring.
    

Temporary fix

Comments

APAR Information

  • APAR number

    IV29908

  • Reported component name

    JIT

  • Reported component ID

    620700124

  • Reported release

    260

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2012-10-10

  • Closed date

    2012-10-10

  • Last modified date

    2012-10-10

  • APAR is sysrouted FROM one or more of the following:

  • APAR is sysrouted TO one or more of the following:

    IV29909

Fix information

  • Fixed component name

    JIT

  • Fixed component ID

    620700124

Applicable component levels

  • R260 PSY

       UP

  • R600 PSY

       UP



Document information

More support for: Runtimes for Java Technology
Just In Time (JIT) Compiler

Software version: 260

Reference #: IV29908

Modified date: 10 October 2012