raimue

A temporary failure means that the job failed only once and then starts running again. If you want to investigate why it failed, you will need the output of that particular failed run.

I already explained above why the existence of linux/landlock.h is not sufficient. Why do you still question it? If you know a bit about system programming and how configure checks work, the change in itself is totally reasonable.

Now we are running in circles. As you see in the git commit, the compile check was added because the existance of linux/landlock.h alone was not enough to check that the feature can be used.

This header defines the data types for the Linux kernel interface, but not how the syscall landlock_create_ruleset(2) will be issued. That is provided by libc either as a separate wrapper function (does not exist in glibc) or the implementation needs to use syscall(SYS_landlock_create_ruleset, ...), with the constant also being provided by libc. That is how it works for all syscalls and you won't be able to change this.

Read the code of the check again. It mostly checks that the required SYS_* constants are defined to be able to use the syscalls. You can compile this on a system that does not have landlock enabled in the running kernel, but the libc (which imports the kernel system call interface) has to provide the syscall numbers.

The question is whether you can expect this format to stay stable and reproducible across git versions. Remember the fallout from git 2.38 when the output of 'git archive' changed. Although for this backup use case it would just mean the next backup with a new format would make a full copy once.

In the 2000s, Apple ran a big campaign with the phrase "I'm a Mac - I'm a PC" to highlight the difference.