The build was broken by the recent libffi update (53a04a2df0) because of this upstream change:ef76205647I have changed the usage of FFI_SYSV as gentoo suggests: https://wiki.gentoo.org/wiki/Libffi_3.3_porting_notes/FFI_SYSV I'm not entirely sure if that is the right call here, but I haven't noticed any regressions in my testing and its definitely better than a broken build. Upstream: https://gitlab.com/embeddable-common-lisp/ecl/issues/302