gcc/testsuite/gfortran.dg/isnan_1.f90

   1 ! Test for the ISNAN intrinsic
   2 !
   3 ! { dg-do run }
   4 ! { dg-add-options ieee }
   5 !
   6   implicit none
   7   real :: x
   8   x = -1.0
   9   x = sqrt(x)
  10   if (.not. isnan(x)) STOP 1
  11   x = 0.0
  12   x = x / x
  13   if (.not. isnan(x)) STOP 2
  14
  15   x = 5.0
  16   if (isnan(x)) STOP 3
  17   x = huge(x)
  18   x = 2*x
  19   if (isnan(x)) STOP 4
  20 end