https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61933
--- Comment #8 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> --- You might notice that we redefined existence to be whether or not it is connected. Units get connected when opened so your sample code needs only ask: IF ((.NOT.is_open).AND.(istat == 0)) RETURN Whether this is what we really want to do of course is open to discussion. The other definition for existence is .true. for all units except -1 which is moot because -1 will give an error and the test for existence is always .true. and not needed. Also unit existence is processor dependent. In your opinion, should we change it to the other definition? Unit existence is sort of a nebulous situation. Will your code be more portable without the test for existence?