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 "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