Intel® oneAPI Math Kernel Library Developer Reference - Fortran
Checks if the infinity and NaN arithmetic is safe. Called by ilaenv.
ival = ieeeck( ispec, zero, one )
The function ieeeck is called from ilaenv to verify that infinity and possibly NaN arithmetic is safe, that is, will not trap.
INTEGER.
Specifies whether to test just for infinity arithmetic or both for infinity and NaN arithmetic:
If ispec = 0: Verify infinity arithmetic only.
If ispec = 1: Verify infinity and NaN arithmetic.
REAL. Must contain the value 0.0
This is passed to prevent the compiler from optimizing away this code.
REAL. Must contain the value 1.0
This is passed to prevent the compiler from optimizing away this code.
INTEGER.
If ival = 0: Arithmetic failed to produce the correct answers.
If ival = 1: Arithmetic produced the correct answers.