Nerves Toolchains

This is an umbrella project for all of the Nerves toolchains.

See the subdirectories for the actual toolchains and the nerves_toolchain_ctng directory for the build scripts.

Installation

See nerves_toolchain_ctng/README.md for preparing your system for building the toolchains.

Building

The normal procedure is to run ./build_release.sh to build everything or go to one of the toolchain subdirectories to build the toolchain. This process uses mix. Sometimes bringing in Elixir obfuscates the build process. To build manually, run something like:

./nerves_toolchain_ctng/build.sh nerves_toolchain_arm_nerves_linux_gnueabihf/defconfig work

This will build the toolchain in the work directory. If you want to modify the configuration, you can do it via Crosstool-ng's menuconfig:

<CTRL-C> out of a running build or "killall make", etc.

$ cd work/build
$ ../usr/bin/ct-ng menuconfig

# make modifications

$ ../usr/bin/ct-ng savedefconfig

# merge defconfig changes over to
# nerves_toolchain_arm_nerves_linux_gnueabihf/defconfig or whatever you're
# building. Some configuration options are platform-specific and should be put
# in nerves_toolchain_ctng/defaults/<platform>

64-bit ARM Builds

It's possible to create cross-compilers for 64-bit ARM machines (aarch64) by building the toolchains on a 64-bit ARM machine. Canadian cross builds don't seem to work. Build as you would on an x86_64 Linux machine.

NOTE: "aarch64 for Darwin" is called arm64. They're slightly different. See the gcc arm64 port.

Canadian cross builds for Raspberry Pi (arm)

It's possible to build a toolchain that runs on the Raspberry Pi on x86 Linux. This is called a Canadian-cross. To do so, first clone the Raspberry Pi cross-toolchain:

git clone git://github.com/raspberrypi/tools.git

Then run a toolchain build as follows:

export HOST_OS=linux
export HOST_ARCH=arm
export PATH=<path to tools>/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64/bin
./nerves_toolchain_ctng/build.sh <toolchain/defconfig> <build_dir>

Canadian cross builds for Windows

sudo apt install g++-mingw-w64-x86-64

Then

export HOST_OS=mingw32
./nerves_toolchain_ctng/build.sh <toolchain/defconfig> <build_dir>