https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119633
--- Comment #2 from Simon Sobisch <simonsobisch at gnu dot org> --- Nearly agreed. As long as there is no "WITH DEBUGGING" active (which you can warn or even error on) an indicator D is, just as a * or a / an indicator defining that the line has no executable code. It can also "overlook" the USE FOR DEBUGGING paragraphs, only executing them on explicit PERFORM, that would solve the parser issue and let existing programs be compiled without a recode.