I get an error building cesm2.1 on cheyenne (that only arises when I have code mods under src.drv), that appears to be due to an already-discovered error in safe_copy in utils.py in /glade/p/cesm/releases/cesm2_1/cime/scripts... described here: ESMCI/cime basically chmod is missing one of its arguments in the python scripts. Is there a way to port the fix described there to the cesm2_1 (and cesm2_1_1) release directories? Any help appreciated!