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LI78234: HARDWARE DFP NOT ALLOWED WITH -QARCH=PWR8

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You can track all active APARs for this component.

APAR status

  • Closed as program error.

Error description

  • Enabling decimal floating point support via -qdfp on builds
    using -qarch=pwr8 is generating calls to the DFP emulate library
    instead of generating hardware instructions.
    
    Adding the -qfloat=nodfpemulate option to force DFP hardware
    calls results in the following message:
    
    1540-2142 (W) "-qfloat=nodfpemulate" is not compatible with
    "-qarch=pwr8". "-qfloat=dfpemulate" is being set.
    

Local fix

  • Compile code using -qarch=pwr7
    

Problem summary

  • PROBLEM DESCRIPTION:
    Compiler was not generating hardware decimal floating point
    instructions when -qarch=pwr8 was set.
    
    USERS AFFECTED:
    Users compiling DFP code for use on POWER8 systems.
    

Problem conclusion

  • A fix was implemented, and the -qarch=pwr8 option now generates
    hardware DFP instructions.
    

Temporary fix

Comments

APAR Information

  • APAR number

    LI78234

  • Reported component name

    XL C/C++ FOR LI

  • Reported component ID

    5725C7300

  • Reported release

    D10

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2014-10-30

  • Closed date

    2014-10-30

  • Last modified date

    2014-10-30

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

    IV61518

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

Fix information

  • Fixed component name

    XL C/C++ FOR LI

  • Fixed component ID

    5725C7300

Applicable component levels



Document information

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

Software version: 13.1

Reference #: LI78234

Modified date: 30 October 2014