The following instructions assume that you already set up Cygwin/Msys
to know about the Microsoft 'cl' compiler and 'nmake'.

1. Download the f2c.exe Fortran to C compiler from netlib from

   http://www.netlib.org/f2c/mswin/f2c.exe.gz

   uncompress it, and put it somewhere in your PATH (e.g. into
   /usr/local/bin).  Make sure it is executable.

2. Download the source code for the f2c runtime library from

   http://www.netlib.org/f2c/libf2c.zip

   and put it into a directory in which you want to have a subdirectory
   where you want to have the subdirectory "libf2c" containing the
   runtime library, e.g., into /usr/local/lib.  Uncompress this file,
   for example by "unzip libf2c.zip" in a Cygwin or MSys window.

3. Compile the Fortran runtime library:

   In the source directory (libf2c), type 'nmake -f makefile.vc all'

   If you encounter an error during the compilation of "err.c" due to
   a missing unistd.h, edit the makefile.vc file and add -DNO_ISATTY
   to the CFLAGS (line 9).

   If you encounter an error during the compilation of "arithchk.c"
   (involving the "comptry.bat" file), edit the makefile.vc file and
   delete the word "comptry.bat" in the 4th from last line.

   NOTE: If you want to generate debug code (using --enable-debug with
   configure), you need to change the makefile.vc file:  Change the
   definition of CFLAGS so that it no longer contains '-Ot1' but
   '-MTd' instead.

4. Edit the script "compile_f2c" in this directory so that the
   variable "f2clibdir" at the beginning is set to the directory
   containing the libf2c runtime library.  (If you installed it in
   /usr/local/lib as suggested above, it is already defined correctly.)

5. Put the compile_f2c script somewhere into your path, e.g., into
   /usr/local/bin - make sure it is executable.

6. To test it, copy the lines at the end of this file into a Fortran
   source file (say, bla.f), and type

     compile_f2c -o f2ctest bla.f

   Running the executable f2ctest.exe hopefully makes you happy.

---------------------- 8< ----------------

      program test
      write (*,*) "It works!"
      end