Demystifying the OVERRIDES mechanism and Bitbake operators - 2022 edition
05-18, 12:55–13:40 (UTC), Kirkstone

Ever wondered how to override some variables or files for a given architecture? Ever seen :append or heard of OVERRIDES mechanism before? Were you ever surprised by the content of one variable? This talk is for you!


Quentin will first talk about :append, :remove, +=, ?= and other operators, with the hope of shedding light on some surprising behaviors, in which context they should be used and how they differ from each other.

Then, the OVERRIDES mechanism will be on the menu, with the different scenario it can be used in and some important gotchas will be presented.

A couple of hints will also be given to debug variables.

Quentin will present the topic from the perspective of a Yocto user.

This is an update of a talk given at Yocto Project Summit 2021.05, with new override syntax and some corrections.

See also:

Quentin is an embedded Linux and Linux kernel engineer mainly working in BSP development and maintenance. He currently works at Theobroma Systems Design und Consulting GmbH.

He has presented multiple talks at Embedded Linux Conferences and has contributed mainly to the Linux kernel and U-Boot bootloader.

His experience with Yocto Project goes from trainer, BSP maintenance, support on IRC to contributions to the documentation.