program volatile_doctest use stringifor_string_t type(string) :: astring character(len=:), allocatable :: acharacter logical :: test_passed(2) astring = ' one ' acharacter = 'three' test_passed(1) = ((acharacter/=astring).eqv..true.) astring = 'the same ' acharacter = 'the same ' test_passed(2) = ((acharacter/=astring).eqv..false.) print '(L1)', all(test_passed) endprogram volatile_doctest