ckormanyos/avr-gcc-build provides shell and YAML scripts to build a modern avr-gcc.

Design goals:

• Use shell and YAML scripts to build modern avr-gcc on-the-fly.
• Build avr-gcc from up-to-date gcc-releases.
• Provide a non-trivial test of the newly-built toolchain(s) based on a real-world project.
• Publish the build artifacts directly from the GHA Workflow-Run(s).
• Occasionally create and publish versioned releases.

Using released or CI-built artifacts can be convenient when you do not actually want to nor need to manually build the avr-gcc toolchain.

Releases and build artifacts consisting of the fully-built avr-gcc toolchain are occasionally created and published for x86_64-linux-gnu (Linux) and x86_64-w64-mingw32 (Windows). These can be readily found on the repo front page and in CI workflow-run download-areas for immediate client use. The releases are permanent, whereby the built artifacts are limited to three days after the Workflow-Run(s).

Workflow:

• Use the shell script avr-gcc-100.sh consistently in each of the Workflow-Run(s).
• The Workflow-Run build-ubuntu.yml builds avr-gcc for the host x86_64-linux-gnu. The script is executed on a GHA ubuntu-latest runner.
• The Workflow-Run build-msys64.yml builds avr-gcc for the host x86_64-w64-mingw32. The script is executed on a GHA windows-latest runner using msys64.
• When building for x86_64-w64-mingw32 on msys64, use a pre-built, dependency-free, statically linked mingw and host-compiler (see notes below). This separate mingw package is unpacked in a directory parallel to the runner workspace and its bin directory is added to the PATH variable.
• GCC prerequisites including GMP, MPFR, MPC, etc. are built on-the-fly in the Workflow-Run.
• Build binutils and partially verify the build artifacts.
• Then build avr-gcc and partially verify the build artifacts.
• Get the main branch of avr-libc from avrdudes/avr-libc and build it with its --prefix matching that of the above-mentioned avr-gcc-build.
• Test the complete, newly built avr-gcc toolchain with a non-trivial compiler test. In the compiler test, we build ref_app (the reference application) from ckormanyos/real-time-cpp. Verify the creation of key build results from ref_app including ELF-file, HEX-file, map files, etc.

Notes:

• This project is distributed under The Unlicense.
• This work has been inspired by (the similar) project ZakKemble/avr-gcc-build.
• The pre-built, dependency-free, statically linked mingw and host-compiler system originate from Steven T. Lavavej's MinGW Distro.