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LI76636: __FENCE NOT BLOCKING MC_FUNC INLINE

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You can track all active APARs for this component.

APAR status

  • Closed as program error.

Error description

  • The compiler is not recognizing the code reordering optimization
    barrier __fence when attempting to protect against code movement
    of a #pragma mc_func function.  This is causing the mc_func
    function to be inlined in more places than expected.
    

Local fix

  • Compiler without optimization.
    

Problem summary

  • PROBLEM DESCRIPTION:
    At -O, a very large '#pragma mc_func' function was replicated
    into five predecessor blocks, despite a __fence().
    
    USERS AFFECTED:
    Those using very large mc_func machine code functions.
    

Problem conclusion

  • mc_func functions of more than 3 instructions will not normally
    be replicated
    

Temporary fix

Comments

APAR Information

  • APAR number

    LI76636

  • Reported component name

    XL C/C++ FOR LI

  • Reported component ID

    5724X1400

  • Reported release

    B10

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2012-02-06

  • Closed date

    2012-02-06

  • Last modified date

    2012-02-06

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

    IV11119

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

Fix information

  • Fixed component name

    XL C/C++ FOR LI

  • Fixed component ID

    5724X1400

Applicable component levels



Document information

More support for: XL C/C++ for Linux

Software version: B10

Reference #: LI76636

Modified date: 06 February 2012