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LI76610: NON VIRTUAL THUNK ERROR AT LINK TIME

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • When compiling a test case that makes use of inline asm, you may
    get a link error related to non virtual thunks.
    
    Below is an example of the error message you may see:
    $ //Link step
    .
    .
    echo Linking...
    `_ZThn4_N7madness19DependencyInterfaceD1Ev' referenced in
    section `.rodata' of libMADworld.a(worldtask.o): defined in
    discarded section
    `.gnu.linkonce.t._ZThn4_N7madness19DependencyInterfaceD1Ev' of
    libMADworld.a(worldtask.o)
    `_ZThn4_N7madness19DependencyInterfaceD0Ev' referenced in
    section `.rodata' of libMADworld.a(worldtask.o): defined in
    discarded section
    `.gnu.linkonce.t._ZThn4_N7madness19DependencyInterfaceD0Ev' of
    libMADworld.a(worldtask.o)
    $
    
    If you do a c++filt on the above symbols, you get:
    $c++filt _ZThn4_N7madness19DependencyInterfaceD1Ev
    non-virtual thunk to
    madness::DependencyInterface::~DependencyInterface()
    $
    

Local fix

  • n/a
    

Problem summary

  • USERS AFFECTED:
    Users using assembly and C++ thunks may be affected by this
    issue.
    
    PROBLEM DESCRIPTION:
    GNU linker (ld) reports link errors when xlCcode generates c++
    thunk sections. The reason is c++ thunk sections are made as
    'linkonce' but will be referred locally from .rodata.
    In this condition, since there may be section discarded (from
    different object files), ld can not guarantee the reference is
    local.
    Therefore the error is reported.
    

Problem conclusion

  • The compiler has been fixed to make the 'linkonce' symbols
    globally week, which eliminates this error.
    

Temporary fix

Comments

APAR Information

  • APAR number

    LI76610

  • Reported component name

    XL C/C++ AE BG/

  • Reported component ID

    5799HJE00

  • Reported release

    900

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2012-02-04

  • Closed date

    2012-03-27

  • Last modified date

    2012-03-27

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

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

    IV18499 LI76793

Fix information

  • Fixed component name

    XL C/C++ AE BG/

  • Fixed component ID

    5799HJE00

Applicable component levels

  • R900 PSY

       UP

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Document Information

Modified date:
17 October 2021