DI extensions implementing the CompilerPassInterface will be processed automatically

[xabbuh]

With the ExtensionCompilerPass from symfony/symfony#13761, container extensions implementing the CompilerPassInterface will be executed automatically during compilation of the container.

[stof]

Your description is wrong. They don't implement a new interface (which does not exist). they implement the existing CompilerPassInterface (and we have a new ExtensionCompilerPass used in the component automatically and responsible for the new feature)

[xabbuh]

Oh, good catch. Thanks @stof.

[xabbuh]

see #5920 for the PR