meta-external-toolchain

OpenEmbedded/Yocto layer for the Sourcery G++ toolchain

Dependencies

• openembedded-core layer, with a matching branch (i.e. master of oe-core and master of meta-sourcery).
• bitbake, with a matching branch.
• An installed Sourcery G++ toolchain
• An existing build directory configured for this bitbake and openembedded-core.

Usage & Instructions

• If it’s an ia32 toolchain, make sure you did not let it modify your PATH, and if you did, remove it.

This is necessary because the ia32 Sourcery G++ toolchain shipped non-prefixed binaries (e.g. gcc rather than i586-none-linux-gcc), which means bitbake would be unable to run the host’s gcc directly anymore.

• Add the meta-sourcery layer to your BBLAYERS in conf/bblayers.conf. Please make certain that it is listed before the meta layer, as this ensures meta-sourcery gets priority over meta.
• Set EXTERNAL_TOOLCHAIN = "/path/to/your/sourcery-g++-install" in conf/local.conf.
• If the external toolchain was built with linux-libc-headers from the 4.8 Linux kernel or newer, set KERNEL_48_PATCH_REMOVE = "" in conf/local.conf to fix the build of the ppp recipe.

Optional Functionality

• If the user chooses to, they may optionally decide to rebuild the Sourcery G++ glibc from source, if they have downloaded the corresponding source archive from Mentor Graphics. To so, set TCMODE = "external-sourcery-rebuild-libc", rather than relying on the default value of external-sourcery. After setting TCMODE appropriately, you must also set SOURCERY_SRC_FILE = "/path/to/your/sourcery-g++-source-tarball" or SOURCERY_SRC_URI = "http://some.domain/some-path".

Behavior

The meta-sourcery layer.conf automatically defines TCMODE for us. The tcmode performs a number of operations:

• Sets TARGET_PREFIX appropriately, after determining what prefix is in use by the toolchain
• Sanity checks EXTERNAL_TOOLCHAIN: does the path exist? does the expected sysroot exist?
• Sets preferences so that external recipes are used in preference to building them from source, including cross recipes which link/wrap the toolchain cross binaries

Contributing

To contribute to this layer, please fork and submit pull requests to the github repository, or open issues for any bugs you find, or feature requests you have.

Maintainer

This layer is maintained by Mentor Graphics Corporation. Please direct all support requests for this layer to the GitHub repository issues interface.

To Do List

See TODO.md.