User options: C while running preprocessor, copy comment D see identifier following as a macro E run preprocessor only I expand include table with directory name following M set identifier length n don't generate register messages L don't generate linenumbers and filename indications p trace P in running the preprocessor do not output '# line' lines R restricted C T take path following as directory for storing temporary file(s) U undefine predefined name V set objectsize and alignment requirements w suppress warning diagnostics Debug options: d perform a small dataflow analysis f dump whole identifier table, including macros and reserved words h supply hash table statistics i print name of include files m supply memory allocation statistics r right-adjust bitfield t dump table of identifiers u unstack L_UNIVERSAL x dump expressions