The GitLab cache is kept across jobs, whether they succeeded or not: this means that if a compiler check fails during the Meson configuration, the small compiler program gets cached and restored the next time the job is run, thus failing again.
The GitLab cache is kept across jobs, whether they succeeded or not: this means that if a compiler check fails during the Meson configuration, the small compiler program gets cached and restored the next time the job is run, thus failing again.