GCC for RISC OS

Using GCC under RISC OS

Setup

GCC is very easy to setup on RISC OS. The following is what you need to get started with a fully working C compiler.

• Download GCC base, C Compiler and GCC documentation.
• Unpack these 3 archives to the same place, to a !gcc application.
• Download the support modules needed by UnixLib SharedUnixLibrary and Digital Renderer and Iconv (Iconv A9home version). You can drop this over your existing !System, but we strongly recommend using a system merge utility.
• Double-click on !gcc - if nothing untoward happens, you're ready to go.

Additional languages and tools

You may also wish to install one or more of the following components as well :

• C++ compiler
• Fortran compiler
• various utils (bison, make, zip, gzip, flex, diff, ...)
• CMunge, a module header creation tool (CMHG clone).

RISC OS GCC Tutorials and information

• C in RISC OS.
• GCC tutorial
• GCC processor target options
• Using UnixLib

In addition, the !gcc application itself contains a number of examples (inside !gcc.examples).

Distributing GCC compiled programs

GCC can compile programs using either the SharedCLibrary or SharedUnixLibrary as runtime libraries.

SharedCLibrary

When you distribute a GCC compiled program and are using the SharedCLibrary as runtime library (i.e. using option -mlibscl), then no additional support files generally need to be made available with your program.

GCC does produce code which requires a recent version of the SharedCLibrary, however, so you should check (in the !Run file) that your user has a suitably up-to-date version installed. See the Castle documentation for details of this and the Iyonix download page for recent versions of SharedCLibrary suitable for RiscPCs.

Note that all new RISC OS platforms ship with a sufficiently up-to-date version of the module present already.

SharedUnixLibrary

When you are using UnixLib as runtime library (and that's the default runtime library), then an up-to-date version of some UnixLib support modules need to be used together with your program. The following is an overview of these support modules :

• SharedUnixLibrary module (mandatory) : http://www.riscos.info/downloads/gccsdk/sharedunixlib/system.zip
• Digital Renderer module (only needed when your code is using the OSS sound interface via the /dev/dsp device) : http://www.riscos.info/downloads/gccsdk/sharedunixlib/system.zip
• Iconv module (only needed when your code is using iconv routines, note temporary separate A9 home version) : http://netsurf.sourceforge.net/iconv/
• CryptRandom module (only needed when random data is read via /dev/(u)random device) : http://www.markettos.org.uk/
• !UnixHome application (typically required by some ported Unix programs wishing to store configuration files and settings in the Unix user's home directory) : !UnixHome. The !UnixHome application should be 'seen' by the RISC OS Filer before they can make use of it.

The modules SharedUnixLibrary, Digital Renderer, Iconv and CryptRandom will be RMEnsure'd with their minimal needed version number by the UnixLib code at the moment their functionality is needed. Appropriate error message will be returned when these modules are not available or when they do not have a sufficently high version number.

When you distribute a copy of these UnixLib support modules with your program, please also mention the URLs in documentation and/or installation notes or program where up-to-date versions can be found.

Useful programs

The following list contains useful programs helping you to develop with GCC on RISC OS :

• Sourcery : Sourcery will manage the source code that makes up a project but it will also manage the various resources files that are required to produce a RISC OS application. These include Sprite, Message and Template files.
• ProfileMod : ProfileMod can be used to profile your code at expense of having to recompile it with the GCC option -finstrument-functions.
• dmalloc port : dmalloc can be used to find memory leaks or memory corruptions due to wrong malloc()/free()/etc. use. It has been ported to RISC OS and is currently located in GCCSDK Autobuilder in the develop/dmalloc subdirectory.

Links

• GCC/GCCSDK home