Available at https://ftp.gnu.org/gnu/libffcall/libffcall-2.2.tar.gz
New in 2.2: * Added support for the following platforms: (Previously, a build on these platforms failed.) - armv6 (Raspberry Pi): Linux. - hppa: Linux 32-bit. - riscv32: Linux with ilp32d ABI. - riscv64: Linux with lp64d ABI. * The build for the mips 32-bit ABI is now compatible with toolchains for the 'fpxx' ABI variant. The downside is that the mips1 architecture is no longer supported. * Fixed a bug regarding passing of more than 8 arguments on the following platforms: - arm64: Linux 64-bit. * Fixed a stack corruption bug on the following platforms: - hppa: HP-UX 32-bit. According to [1], you are packaging libffcall for Debian. I invite you to upgrade to version 2.2. It is expected to build on all official Debian ports. Best regards, Bruno [1] https://packages.debian.org/buster/libffcall-dev