I am using Ubuntu 12.04 LTS (32bit-i386) in my desktop PC. I need g77 compiler for some specific applications. The app can only be installed after having g77 compiler. This specific app is designed based on g77 fortran compiler and can't be used with gfortran which is the standard available compiler in 12.04 LTS. And guide me the procedure to install g77 in 12.04. I have been trying apt-get update & apt-get install g77 after changing the sources.list file. After processing I am able to install g77 but when i try to compile a fortran program, it shows error /usr/bin/ld: cannot find crt1.o: No such file or directory /usr/bin/ld: cannot find crti.o: No such file or directory /usr/bin/ld: cannot find -lgcc_s collect2: ld returned 1 exit status Please help me. I m struggling a lot to fix this.