Since OCaml 4.07 (released 2018-07-10) the always-loaded standard library module has been called Stdlib. The old Pervasives module was finally removed in OCaml 5. $ perl -pi.bak -e 's/Pervasives\./Stdlib./g' -- `git ls-files` OCaml >= 4.07 is now required. Also update the common submodule with: commit d61cd820b49e403848d15c5deaccbf8dd7045370 Author: Jürgen Hötzel Date: Sat May 20 18:16:40 2023 +0200 Add support for OCaml 5.0