A change from "main" arch make_clickable_callback(MAGIC_URL_FULL, '(', 'https://gitlab.archlinux.org/archlinux/devtools/-/merge_requests/229', '', ' class="postlink"')) seems to have found its way to arm, where it breaks things.
I get: "unrecognized command-line option '-mno-omit-leaf-frame-pointer'; did you mean '-fno-omit-frame-pointer'?"
Removing -mno-omit-leaf-frame-pointer from /etc/makepkg.conf fixes the package build.