Frontend app to the GCC port of fortran, requires bits from gcc-3.4.6-release-2 to work.

Download the skeleton application (!GNUF77, 61 Kbytes) and unzip it to a suitable directory
Download the g77.zip (2.15 Mbytes).
Download the gcc.zip (2.51 Mbytes)
the g77.zip just contains an application called !gcc. Extract the files:

    !gcc.bin.g77
    to your new !GNUF77.bin.g77
    !gcc.bin.arm-riscos-aof.3_4.f771
    to !GNUF77.bin.f771
    !gcc.bin.arm-riscos.3_4.apcs32.abs.unixlib.o.libg2c
    to !GNUF77.bin.o.libg2c
    there is also a directory of docs which you may find useful. The file g77-readme has a list of error numbers and the file g77 has all the possible compiler options. You should read the beginnings of these to be aware of the GNU license. 

the gcc.zip also contains an application !gcc. Extract the files:

    !gcc.bin.arm-riscos-aof.3_4.as
    to !GNUF77.bin.as
    !gcc.bin.arm-riscos-aof.3_4.apcs32.abs.unixlib.o.libgcc
    to !GNUF77.bin.o.libgcc
    !gcc.bin.arm-riscos-aof.3_4.apcs32.abs.unixlib.o.unixlib
    to !GNUF77.bin.o.unixlib
    !gcc.bin.gcc
    to !GNUF77.bin.gcc
    !gcc.bin.drlink
    to !GNUF77.bin.drlink