AVR Toolchain with libstdc++ Support

Using in PlatformIO

This toolchain comes with a companion platform, so the easiest way to use it is as follows:

[env]
platform = https://github.com/modern-avr/platform.git
board = ...

That's it!

What Does It Change?

Aside from providing a newer compiler, it makes a few changes to the build flags:

For C++:

• Replaces -std=c++11 with -std=gnu++26.
• Removes -fpermissible to encourage better coding practices.
• Adds -Wno-volatile because Arduino framework uses volatile in a now deprecated way.

For C:

• Replaces -std=c11 with -std=gnu23.

You can re-enable or disable any flags using build_flags and build_unflags, as usual.

Supported Platforms

Currently, the toolchain has been built for:

• linux_x86_64
• windows_amd64

Pull requests for additional platforms are welcome.

Building from Source

Prerequisites:

• Docker
• GNU Make
• Bash

Toolchain	Space	Time
windows_amd64	72 GiB	125 min
linux_x86_64	52 GiB	82 min

The build times were measured on an AMD Ryzen 9 7845HX 18-core VM with 32 GB RAM. If you build both toolchains, you'll save around 2.5 GiB due to base image overlap.

Space usage is approximate, as accurate measurement is difficult due to cleanups. Having 100 GiB of free space should suffice.

Currently, only building on Linux is supported. If you can make this run on Windows or macOS, please submit a pull request.

Configuring (Optional)

Run:

make menuconfig

Note: Building Bison and Mold is broken on Windows, so they are disabled. Building DTC for Windows requires patches (included).

Please do not change anything related to paths or filenames, as the packaging scripts will not recognize new values.

Building

To build the linux_x86_64 toolchain:

make linux_x86_64

To build the windows_amd64 toolchain:

make windows_amd64

To build all toolchains (e.g., both):

make all

Cleaning Up

To remove just-built toolchains:

make clean

To also remove the build cache:

make distclean

Troubleshooting

Build has not completed

Simply run the build command again.

Build has completed with an error

The most common reasons for failure are:

1. Insufficient disk space.
2. Insufficient RAM.

To mitigate this, run:

make menuconfig

and reduce the number of concurrent jobs.

When a build fails, build.log (if available) is automatically copied to the repository root, overwriting any previous version.

To resume building, rerun the build command. It will pick up from the last successful step automatically.

To resume building from a specific step, run:

make linux_x86_64 RESUME=linker

Replace the target OS and build step accordingly.

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Copyright © 2024 toriningen toriningen.me@gmail.com

This work is free. You can redistribute it and/or modify it under the terms of the Do What The Fuck You Want To Public License, Version 2, as published by Sam Hocevar. See the COPYING file for more details.