Compiling HelenOS From Source

This section explains how to compile HelenOS from latest source code.

Attention Newbies

This method is not recommended for beginners. If you are running HelenOS for the first time, please run a pre-built, supported HelenOS image (see instructions in that article).

Compiling an operating system is not quite simple as the configure && make && make install you use to compile your favorite application. If you still want to do it, please follow these instructions carefully. If you don't follow the instructions to the letter, it won't compile (or it will not run) and then don't bother us on the mailing list, please. We are somewhat tired of telling the people again and again to install the fine compiler toolchain.

1. Get the sources

Checkout the latest sources from our central Bazaar repository

$ bzr checkout bzr://bzr.helenos.org/mainline HelenOS

Note: To get versions older than 0.4.1 you have to access the original Subversion repository

$ svn checkout svn://svn.helenos.org/HelenOS/trunk HelenOS

2. Build a supported cross-compiler

Use our script to install a supported cross-compiler toolchain

$ cd HelenOS/tools
$ ./toolchain.sh ia32

Note: In older revisions of the source tree the toolchain.sh script was present in the contrib directory (not the tools directory where it is now).

3. Did you install the compiler toolchain? Good.

If you did not, it won't work! You can't use the default compiler installed on your system to build HelenOS. Don't even try to pester us about that. It won't work. Because it won't. It can't.

Why can't it work?

• Tool versions: We only test HelenOS on the one single version of GCC, binutils, etc. We don't have the resources to test other versions. Other versions have bugs (or lack required features). It won't compile.
• Different ABIs: Each OS has a different ABI and different set of compiler settings. If you build binaries with your native compiler, they will run fine in your OS, but certainly not in HelenOS!
• -Werror: Developer builds use -Werror and each compiler version produces different warnings. Thus, you will get warnings and these get turned into errors.

4. Configure and build

Go back to the source root and start the build process

$ cd ..
$ make PROFILE=ia32

Now HelenOS should automatically start building.

5. Run it

When you get the command line back, there should be an image.iso file in the source root directory. If you have Qemu, you should be able to start HelenOS by running

$ qemu -cdrom image.iso

there are also some start scripts and configuration files for other emulators in contrib/conf.

Advanced Topics

Which profiles are available?

Look under the defaults/ directory. As of 2011-03-22 the list is:

amd64
arm32/GXemul
arm32/gta02
arm32/integratorcp
ia32
ia64/i460GX
ia64/ski
mips32/GXemul
mips32/msim
ppc32
sparc64/niagara
sparc64/serengeti
sparc64/ultra
special/abs32le

Manual Configuration

Please Note: Normally you don't need to do this. Manual configuration was mostly used in the past where HelenOS had no command line. Nowadays manual configuration (and configuration options in general) are used much less and only when absolutely necessary (e.g. if you really need to build a smaller system). If you configure HelenOS manually and it does not build (or does not work), you probably hit a combination of the configuration options that nobody tested properly. In that case you should file a bug.

With manual configuration you can change screen resolution, disable building of some components, etc.

Warning: Do not select a different compiler unless you really know what you are doing! If you use gcc_native instead of gcc_cross, it won't work, so please don't ask in the mailing list! Building HelenOS with a native compiler is not supported!

To configure:

$ make distclean && make config

alternatively

$ make distclean && make

this will cause HelenOS build to automatically start once you are done with the configuration.

Building release files

This procedure is used to create HelenOS realease files before releasing a new HelenOS version, or for simulating that process. The resulting system image is based on one of the predefined configuration profiles (as opposed to the current configuration!)

Before building release files make sure you have no uncommitted changes. These will not be build since we are building from exported sources.

To build all release files go to the source root and run:

$ make release

To build an individual release file go to the source root and run:

$ make -C release release PROFILES=profile_name

This builds a release file (boot image / disk image) based on the specified configuration profile profile_name.