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Compiler Options

     -c        Suppress linking with ld(1) and produce a .o  file
               for each source file.  A single object file can be
               named explicitly using the -o option.

     -C        Prevent the C preprocessor from  removing
     -E        Run the source file through  the  C  preprocessor,
               only.  Sends the output to the standard output, or
               to a file named with the -o option.  Includes  the
               cpp line numbering information.  (See also, the -P

     -g        Produce additional symbol  table  information  for
               dbx(1) and dbxtool(1).  When this option is given,
               the -O and -R options are suppressed.

     -help     Display helpful information about compiler.

               Add pathname to the list of directories  in  which
               to   search   for  #include  files  with  relative
               filenames  (not  beginning  with  slash  /).   The
               preprocessor  first searches for #include files in
               the  directory  containing  sourcefile,  then   in
               directories  named  with  -I options (if any), and
               finally, in /usr/include.

     -llibrary Link with  object  library  library  (for  ld(1)).
               This option must follow the sourcefile arguments.

               Add directory to the list of directories  contain-
               ing  object-library  routines  (for  linking using

     -M        Run only the macro preprocessor  on  the  named  C
               programs,  requesting  that  it  generate makefile
               dependencies and send the result to  the  standard
               output  (see  make(1)  for details about makefiles
               and dependencies).

     -o outputfile
               Name the output file outputfile.  outputfile  must
               have  the  appropriate suffix for the type of file
               to be produced  by  the  compilation  (see  FILES,
               below).  outputfile  cannot be the same as source-
               file (the compiler will not overwrite  the  source

     -O[level] Optimize the object code.  Ignored when either  -g
               or  -a  is  used.   -O  with  the level omitted is
               equivalent to -O2.  level is one of:

                    1    Do postpass assembly-level  optimization

                    2    Do global  optimization  prior  to  code
                         generation,   including  loop  optimiza-
                         tions, common subexpression elimination,
                         copy propagation, and automatic register
                         allocation. -O2 does not optimize refer-
                         ences  to  or definitions of external or
                         indirect variables.

               If the optimizer runs out of memory, it  tries  to
               recover  by  retrying  the  current procedure at a
               lower level of optimization and resumes subsequent
               procedures at the original level.

      -P        Run the source file through  the  C  preprocessor,
               only.  Puts the output in a file with a .i suffix.
               Does not include cpp-type line number  information
               in the output
Fri May 20 13:40:49 BST 1994