CK( x==-1 ) is NOT correct!
  values: CHECK( 0 == -1 )

===============================================================================
[doctest] test cases:      2 |      2 passed |      0 failed |      0 skipped
[doctest] assertions:      2 |      2 passed |      0 failed |
[doctest] Status: SUCCESS!
===============================================================================
[doctest] assertions on all processes:   5 |   4 passed |      1 failed |
======================================================