GCC crosstoolchain build script

This is a simple script to build gcc based (cross) toolchains for various platforms. It is much like crosstool-ng, just simpler.

The buildscript is able to build toolchains and cross-toolchains for Linux hosts and targets Linux, Windows (mingw) as well as baremetal targets.

Specifically these target architectures are currently supported:

- arm 
- arm64 
- avr8
- cortex-m0 
- cortex-m3 
- cortex-m4 
- riscv32 
- riscv32-baremetal 
- riscv64 
- riscv64-baremetal
- riscv64-uclibc 
- x86 
- x86_64 
- x86_64_mingw 
- x86_mingw 

Supported GCC versions:

• GCC-latest
• GCC-14
• GCC-13
• GCC-12
• GCC-11

Please be aware that some target/version combinations might not work.

Prebuilt toolchains can be downloaded here (note: links are only valid 90 days after the last successful github ci runner)

https://nightly.link/franzflasch/gcc-build-tools/workflows/arm/main/toolchain_built_from_tar
https://nightly.link/franzflasch/gcc-build-tools/workflows/arm64/main/toolchain_built_from_tar
https://nightly.link/franzflasch/gcc-build-tools/workflows/avr8/main/toolchain_built_from_tar
https://nightly.link/franzflasch/gcc-build-tools/workflows/cortex-m0/main/toolchain_built_from_tar
https://nightly.link/franzflasch/gcc-build-tools/workflows/cortex-m3/main/toolchain_built_from_tar
https://nightly.link/franzflasch/gcc-build-tools/workflows/cortex-m4/main/toolchain_built_from_tar
https://nightly.link/franzflasch/gcc-build-tools/workflows/riscv32/main/toolchain_built_from_tar
https://nightly.link/franzflasch/gcc-build-tools/workflows/riscv32-baremetal/main/toolchain_built_from_tar
https://nightly.link/franzflasch/gcc-build-tools/workflows/riscv64/main/toolchain_built_from_tar
https://nightly.link/franzflasch/gcc-build-tools/workflows/riscv64-baremetal/main/toolchain_built_from_tar
https://nightly.link/franzflasch/gcc-build-tools/workflows/riscv64-uclibc/main/toolchain_built_from_tar
https://nightly.link/franzflasch/gcc-build-tools/workflows/x86/main/toolchain_built_from_tar
https://nightly.link/franzflasch/gcc-build-tools/workflows/x86_64/main/toolchain_built_from_tar
https://nightly.link/franzflasch/gcc-build-tools/workflows/x86_64_mingw/main/toolchain_built_from_tar
https://nightly.link/franzflasch/gcc-build-tools/workflows/x86_mingw/main/toolchain_built_from_tar

NOTE: Make sure to extract the prebuilt toolchains to /opt/local/ otherwise there might be issues for certain builds.

Prerequisites

To build a toolchain, you need to do the following:

A Linux distribution (the script has been tested on Ubuntu 22.04)
Core developer packages

• For Ubuntu 22.04:

sudo apt install -y wget build-essential make gawk git subversion texinfo autoconf autopoint pkg-config gettext txt2man liblzma-dev libssl-dev libz-dev flex bison libexpat1-dev rsync file

In case you want to build a baremetal target you also need to install:

• For picolibc:

sudo apt install -y python3-pip
sudo pip3 install meson ninja

Install directory

IMPORTANT: Create the folder /opt/local/ and ensure that you have write permissions otherwise the script wont work!!

Using the script

Once you have set up your environment, you can use the script like this:

1. Clone the repository

git clone https://github.com/franzflasch/gcc-build-tools

2. Add the script to your path

cd gcc-build-tools
export PATH=$PWD:$PATH

3. Create a work directory for your build

mkdir ~/gcc-builds
cd ~/gcc-builds

4. Use it!

build-gcc -h

The printout will show you how to run the script.

Example commands:

# build a riscv64-uclibc toolchain, stripping binaries, verbose mode
build-gcc -a riscv64-uclibc -v 14 -s -V

# Build a toolchain for x86_64
./build-gcc -a x86_64 -v 14

# Build a toolchain for arm64
./build-gcc -a arm64 -v 14

# Build a toolchain for arm
./build-gcc -a arm -v 14

# Build a toolchain for riscv linux
./build-gcc -a riscv64 -v 14

# Build a toolchain for avr microcontrollers
./build-gcc -a avr8 -v 14 -t

# Build a toolchain for arm cortex m3/m4 microcontrollers
./build-gcc -a cortex-m3 -v 14 -t

# Build a toolchain for riscv baremetal (sifive hifive1)
./build-gcc -a riscv32-baremetal -v 14

After compilation

The end result will be placed into /opt/local/ e.g. /opt/local/cross-tool-riscv64-uclibc-gcc14/.

To use the toolchain just add /opt/local/cross-tool-riscv64-uclibc-gcc14/bin to your $PATH and thats it.

Notes on using the toolchain

Building a fully static linked executable:

<target-triple>-gcc -o hello -static hello.c

With OpenMP:

<target-triple>-gcc -o omp_helloc -static -fopenmp omp_hello.c

For shared libraries ensure that you are building using the internal toolchain libs instead of ones already installed on the host linux - here for x86_64 openmp example:

x86_64-linux-gnu-gcc -o omp_helloc -Wl,--rpath=toolchain/lib64 -Wl,--rpath=toolchain/x86_64-linux-gnu/lib/ -Wl,--dynamic-linker=toolchain/x86_64-linux-gnu/lib/ld-linux-x86-64.so.2 -fopenmp omp_hello.c

For crosscompile targets it is probably necessary to install those libs into the target rootfs.

For developers

Adding a new target should be rather easy:

• Add a new target file in configs/targets. Look at the existing targets to get an idea how to add your own.
• There are default configs defined in configs/targets_config.sh that should be used as a base if possible.
• SRC URLs for the various open source packages (gcc, binutils etc.) are handled in configs/common.sh.
• SRC VERSIONs are handled either in configs/git_source_config.sh and configs/tar_source_config.sh.
  • git_source_config.sh defines SRC URLs for git repositories.
  • tar_source_config.sh defines SRC URLs for tarballs.

Pull requests/issues

Feel free to open an issue!

Pull requests are more than welcome as well!