IEEECK is called from the ILAENV to verify that Infinity and


 possibly NaN arithmetic is safe (i.e. will not trap).

ISPEC

          ISPEC is INTEGER


          Specifies whether to test just for inifinity arithmetic


          or whether to test for infinity and NaN arithmetic.


          = 0: Verify infinity arithmetic only.


          = 1: Verify infinity and NaN arithmetic.

ZERO

          ZERO is REAL


          Must contain the value 0.0


          This is passed to prevent the compiler from optimizing


          away this code.

ONE

          ONE is REAL


          Must contain the value 1.0


          This is passed to prevent the compiler from optimizing


          away this code.


  RETURN VALUE:  INTEGER


          = 0:  Arithmetic failed to produce the correct answers


          = 1:  Arithmetic produced the correct answers

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

December 2016