https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87244
kargl at gcc dot gnu.org changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |kargl at gcc dot gnu.org --- Comment #1 from kargl at gcc dot gnu.org --- Your code compiles and executes with gfortran versions 6.4.1, 7.3.1, 8.1.1, and 9.0.0. troutmask:sgk[205] gfcx -o z a.f90 && ./z 0******** Failure to open file: filenames STOP timecomp:first open troutmask:sgk[206] gfc8 -o z a.f90 && ./z 0******** Failure to open file: filenames STOP timecomp:first open troutmask:sgk[207] gfc7 -o z a.f90 && ./z 0******** Failure to open file: filenames STOP timecomp:first open troutmask:sgk[208] gfc6 -o z a.f90 && ./z 0******** Failure to open file: filenames STOP timecomp:first open Version 4.9.2 is no loner supported. I suggest you (or your organization) update to supported version of gfortran.