GCC Software Development Kit
- Open source C, C++, and Fortran compiler and supporting libraries. Native RISC OS compiler, and cross-compiler from Unix.
- http://www.riscos.info/index.php/GCCSDK

Easy C++
- Commercial C/C++ compiler. Overview, ordering, and information about the Vigil debugger.
- http://www.apdl.co.uk/prog.htm

Castle C/C++ Development Suite
- Commercial C/C++ compiler. Features, details of the subscription scheme, and online ordering.
- http://www.castle-technology.co.uk/castle/cinfo.html