Re: Michael Paquier > Is reproducibility something you've brought to a separate thread? > FWIW, I'd be interested in improving this area for the in-core code, > if need be. (Not material for this thread, of course).
All the "normal" things like C compilation are actually already reproducible. The bit addressed by the mentioned patch is that the compiler flags are recorded for later output by pg_config, and that includes -ffile-prefix-map=/path/to/source=. which does improve C reproducibility, but ironically is itself not reproducible when the source is then compiled in a different directory. The patch simply removes that flag from the information stored. https://salsa.debian.org/postgresql/postgresql/-/blob/15/debian/patches/filter-debug-prefix-map Not sure not much of that would be material for inclusion in PG. This fix made PG 10 reproducible in Debian for about a week. Then LLVM happened :D. The .bc files still record the build path, and so far no one has found a way to prevent that: https://tests.reproducible-builds.org/debian/rb-pkg/unstable/arm64/diffoscope-results/postgresql-15.html Afaict that's the last part to be resolved (but it's been a while since I checked). clang seems to have learned about -ffile-prefix-map= in the meantime, that needs to be tested. Christoph
