https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102500
--- Comment #1 from Tobias Burnus <burnus at gcc dot gnu.org> --- While the patch outputs proper warnings, it was deemed to be aggressive by default. Thus, the default value has been downgraded to print by commit Fortran: Improve -Wmissing-include-dirs warnings [PR55534] r12-3825-g83aac698835edcdb3e6d96b856bef1c5f92e5e24 Wed Sep 22 20:58:35 2021 +0200 Can you check whether that fixes the issue?