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IV19669: WRONG .MACHINE TAG WITH OPTIMIZATION ENABLED

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • When compiling an application with the -qarch=pwr7 compile
    option, and enabling optimization level -O2 or -O3, the
    generated .machine pseudo-op incorrectly reads 'pwr6' instead of
    'pwr7'.
    

Local fix

  • Optimization levels -O0, -O4 and -O5 output the correct .machine
    tag.
    

Problem summary

  • PROBLEM DESCRIPTION:
    The .machine tag generated in an output object file depends on
    the highest processor architecture level instruction generated
    by the compiler, not necessarily the -qarch setting.  For
    example, it is possible that compiling with -qarch=pwr7 may only
    generate POWER6-level instructions, which would cause a .machine
    tag of 'pwr6' to be output.
    
    An issue exists where an inline ASM or mc_func block could
    contain a higher level instruction than generated by the
    compiler, resulting in an incorrect .machine tag.
    
    USERS AFFECTED:
    Applications that depend on the .machine tag in an object file.
    Users of -qarch.
    

Problem conclusion

  • The compiler was modified to force the .machine tag to match the
    -qarch setting if an inline ASM or mc_func block is detected.
    

Temporary fix

Comments

APAR Information

  • APAR number

    IV19669

  • Reported component name

    XL C/C++ AIX

  • Reported component ID

    5724X1300

  • Reported release

    B10

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2012-04-13

  • Closed date

    2012-07-05

  • Last modified date

    2012-07-05

Fix information

  • Fixed component name

    XL C FOR AIX

  • Fixed component ID

    5724X1200

Applicable component levels

  • RB10 PSY

       UP

[{"Business Unit":{"code":"BU058","label":"IBM Infrastructure w\/TPS"},"Product":{"code":"SSGH2K","label":"XL C for AIX"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"11.1","Edition":"","Line of Business":{"code":"LOB57","label":"Power"}}]

Document Information

Modified date:
05 July 2012