The results provided with this algorithm were generated using the Sun f77 compiler under Solaris 2.7 with all checking switched off. The Edinburgh Portable Compiler F90 compiler will not compile this code as it picks up array bound failures in the source code. These are caused by arrays in COMMON being declared length 1 in the src file. This is a common, but illegal, means of generating 'dynamic' array space using Fortran 66 and 77. The actual/required array lengths are only declared in the main program. Fixing this would involve a major rewrite of the software
There are a huge number of unused common blocks reported by various tools. The call to a non-standard routine (SYSTEMC) in the routine KILLIT has been commented out. Hollerith strings in FORMAT statements need to be changed to strings and the i1mach used to set i/o channels.