Specifies various floating-point options. These options provide different strategies for speeding up or improving the accuracy of floating-point calculations.
.-:----------------. | .-nospnans-----. | | +-norsqrt------+ | | +-norrm--------+ | | +-norelax------+ | | +-nonans-------+ | | +-maf----------+ | | +-nohsflt------+ | | +-fold---------+ | | +-nofltint-----+ | V +-complexgcc---+ | >>- -qfloat--=----+-nocomplexgcc-+-+--------------------------->< +-fltint-------+ +-nofold-------+ +-hsflt--------+ +-nomaf--------+ +-nans---------+ +-relax--------+ +-rrm----------+ +-rsqrt--------+ '-spnans-------'
Option selections are described in the Notes section below. See also #pragma options.
Using float suboptions other than the default settings may produce varying results in floating point computations. Incorrect computational results may be produced if not all required conditions for a given suboption are met. For these reasons, you should only use this option if you are experienced with floating-point calculations involving IEEE floating-point values and can properly assess the possibility of introducing errors in your program.
You can specify one or more of the following float suboptions.
To compile myprogram.C so that constant floating point expressions are evaluated at compile time and multiply-add instructions are not generated, enter:
xlc++ myprogram.C -qfloat=fold:nomaf
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