man pages for g77

Online Manual

GNU Tools Last change: 1999-02-14
NAME
     g77 - GNU project Fortran Compiler (v0.5.24)

SYNOPSIS
     g77 [option | filename ]...

WARNING
     The information in this man page is an extract from the full
     documentation  of the GNU Fortran compiler (version 0.5.24),
     and is limited to the meaning of some of the options.

     This man page is not up to date, since no volunteers want to
     maintain it.  If you find a discrepancy between the man page
     and the software, please check the Info file, which  is  the
     authoritative documentation.

     If we find that the things in this man page that are out  of
     date cause significant confusion or complaints, we will stop
     distributing the man page.  The  alternative,  updating  the
     man  page  when  we  update  the  Info  file, is impractical
     because the rest of the  work  of  maintaining  GNU  Fortran
     leaves  us  no  time  for that.  The GNU project regards man
     pages as obsolete and should not let  them  take  time  away
     from other things.

     For complete and current documentation, refer  to  the  Info
     file  `g77' or the manual Using and Porting GNU Fortran (for
     version 0.5.24).  Both are made from the Texinfo source file
     g77.texi.

     If your system has the `info' command installed, the command
     `info  g77'  should  work,  unless g77 has not been properly
     installed.  If your system lacks  `info',  or  you  wish  to
     avoid    using    it    for    now,    the   command   `more
     /usr/info/g77.info*' should work, unless g77  has  not  been
     properly installed.

     If g77 has not been properly installed, so that  you  cannot
     easily access the Info file for it, ask your system adminis-
     trator, or the installer of g77 (if you know who that is) to
     fix the problem.

DESCRIPTION
     The C and F77 compilers are integrated; g77 is a program  to
     call  gcc with options to recognize programs written in For-
     tran (ANSI FORTRAN 77,  also  called  F77).   gcc  processes
     input  files through one or more of four stages: preprocess-
     ing, compilation, assembly, and linking.  This man page con-
     tains full descriptions for only F77-specific aspects of the
     compiler,  though  it  also  contains  summaries   of   some
     general-purpose  options.   For  a fuller explanation of the
     compiler, see gcc(1).

     For complete documentation on GNU Fortran, type `info g77'.

     F77 source files use the suffix `.f', `.for', or `.FOR'; F77
     files  to  be  preprocessed  by  cpp(1) use the suffix `.F',
     `.fpp', or `.FPP'; Ratfor source files use the  suffix  `.r'
     (though ratfor itself is not supplied as part of g77).

OPTIONS
     There are many command-line options,  including  options  to
     control  details of optimization, warnings, and code genera-
     tion, which are common to both gcc and g77.  For full infor-
     mation on all options, see gcc(1).

     Options must be separate: `-dr' is quite different from  `-d
     -r '.

     Most `-f' and `-W' options have two contrary forms:   -fname
     and  -fno-name  (or  -Wname  and  -Wno-name).  Only the non-
     default forms are shown here.

     -c   Compile or assemble the source files, but do not  link.
          The  compiler output is an object file corresponding to
          each source file.

     -Dmacro
          Define macro macro with the string `1' as  its  defini-
          tion.

     -Dmacro=defn
          Define macro macro as defn.

     -E   Stop after the preprocessing stage; do not run the com-
          piler  proper.  The output is preprocessed source code,
          which is sent to the standard output.

     -g   Produce debugging information in the operating system's
          native  format (for DBX or SDB or DWARF).  GDB also can
          work with this debugging information.  On most  systems
          that  use  DBX format, `-g' enables use of extra debug-
          ging information that only GDB can use.

          Unlike most other Fortran compilers, GNU Fortran allows
          you  to  use  `-g'  with  `-O'.  The shortcuts taken by
          optimized  code  may  occasionally  produce  surprising
          results:  some  variables you declared may not exist at
          all; flow of control may briefly move where you did not
          expect  it; some statements may not be executed because
          they compute constant  results  or  their  values  were
          already  at  hand;  some statements may execute in dif-
          ferent places because they were moved out of loops.

          Nevertheless it proves possible to debug optimized out-
          put.  This makes it reasonable to use the optimizer for
          programs that might have bugs.

     -Idir
           Append  directory  dir  to  the  list  of  directories
          searched for include files.

     -Ldir
           Add directory dir to the list  of  directories  to  be
          searched for `-l'.

     -llibrary
           Use the library named library when linking.

     -nostdinc
          Do not  search  the  standard  system  directories  for
          header  files.  Only the directories you have specified
          with  -I  options  (and  the  current   directory,   if
          appropriate) are searched.

     -O   Optimize.  Optimizing compilation takes  somewhat  more
          time,  and a lot more memory for a large function.  See
          the GCC documentation for further optimisation options.
          Loop unrolling, in particular, may be worth investigat-
          ing for typical numerical Fortran programs.

     -o file
           Place output in file file.

     -S   Stop after the stage  of  compilation  proper;  do  not
          assemble.   The  output  is  an assembler code file for
          each non-assembler input file specified.

     -Umacro
          Undefine macro macro.

     -v   Print (on standard error output) the commands  executed
          to  run the stages of compilation.  Also print the ver-
          sion number of the compiler driver program and  of  the
          preprocessor  and  the  compiler  proper.   The version
          numbers of g77 itself and the GCC distribution on which
          it is based are distinct.

     -Wall
          Issue warnings for conditions which  pertain  to  usage
          that  we recommend avoiding and that we believe is easy
          to avoid, even in conjunction with macros.

FILES
     file.h    C header (preprocessor) file
     file.f    Fortran source file

     file.for  Fortran source file
     file.FOR  Fortran source file
     file.F    preprocessed Fortran source file
     file.fpp  preprocessed Fortran source file
     file.FPP  preprocessed Fortran source file
     file.r    Ratfor source file (ratfor not included)
     file.s    assembly language file
     file.o    object file
     a.out     link edited output
     TMPDIR/cc*         temporary files
     LIBDIR/cpp         preprocessor
     LIBDIR/f771        compiler
     LIBDIR/libg2c.a    Fortran run-time library
     LIBDIR/libgcc.a    GCC subroutine library
     /lib/crt[01n].o    start-up routine
     /lib/libc.a        standard C library, see intro(3)
     /usr/include       standard directory for #include files
     LIBDIR/include     standard gcc directory for #include
                        files.

     LIBDIR is usually /usr/local/lib/machine/version.

     TMPDIR comes from the environment variable  TMPDIR  (default
     /usr/tmp if available, else /tmp).

SEE ALSO
     gcc(1),  cpp(1),  as(1),  ld(1),  gdb(1),  adb(1),   dbx(1),
     sdb(1).
     `g77', `gcc', `cpp `as', `ld', and `gdb' entries in info.
     Using and Porting GNU Fortran (for  version  0.5.24),  James
     Craig  Burley;  Using  and Porting GNU CC (for version 2.0),
     Richard M. Stallman; The C Preprocessor, Richard  M.  Stall-
     man;  Debugging  with  GDB:  the  GNU Source-Level Debugger,
     Richard M. Stallman and Roland H. Pesch; Using as:  the  GNU
     Assembler, Dean Elsner, Jay Fenlason & friends; gld: the GNU
     linker, Steve Chamberlain and Roland Pesch.

BUGS
     For instructions on how to report bugs, type  `info  g77  -n
     Bugs'.

COPYING
     Copyright (c) 1991-1998 Free Software Foundation, Inc.

     Permission is granted to make and distribute verbatim copies
     of  this  manual provided the copyright notice and this per-
     mission notice are preserved on all copies.

     Permission is granted to copy and distribute  modified  ver-
     sions  of  this  manual  under  the  conditions for verbatim

     copying, provided that the entire resulting derived work  is
     distributed under the terms of a permission notice identical
     to this one.

     Permission is granted to copy and distribute translations of
     this  manual  into  another language, under the above condi-
     tions for modified versions,  except  that  this  permission
     notice  may be included in translations approved by the Free
     Software Foundation instead of in the original English.

AUTHORS
     See the GNU CC Manual for the contributors to GNU  CC.   See
     the online GNU Fortran Manual for the contributors to GNU Fortran.