[OCaml] build on freebsd x64 fails with "recompile with -fPIC"

[fogti]

https://gist.github.com/fogti/be2b57e38a2d0180b4bec9936bfa60f4

[ 60%] Linking C shared library libhacl.so
ld: error: relocation R_X86_64_PC32 cannot be used against symbol 'Hacl_Impl_Chacha20_Vec_chacha20_constants'; recompile with -fPIC
>>> defined in CMakeFiles/hacl.dir/src/Hacl_Chacha20.c.o
>>> referenced by Hacl_Chacha20_Vec128.c
>>>               CMakeFiles/hacl_vec128.dir/src/Hacl_Chacha20_Vec128.c.o:(Hacl_Chacha20_Vec128_chacha20_encrypt_128)
[...]
cc: error: linker command failed with exit code 1 (use -v to see invocation)

uname -a: FreeBSD burton 13.2-RELEASE-p1 [...] GENERIC amd64

[franziskuskiefer]

This is an issue in the C library that's bundled by OCaml where -fPIC is missing.

FreeBSD is currently not supported. But I'm happy to take a patch that fixes the build for FreeBSD.

[fogti]

hacl-packages/CMakeLists.txt

Lines 124 to 128 in 81303b8

	if(${CMAKE_SYSTEM_NAME} MATCHES Linux)
	add_compile_options(
	-fPIC
	)
	endif(${CMAKE_SYSTEM_NAME} MATCHES Linux)

should be extended to also match on ${CMAKE_SYSTEM_NAME} MATCHES FreeBSD. I think that should be able to fix this, but I'm not exactly sure how to test that (because idk how it is packaged for opam)

[franziskuskiefer]

because idk how it is packaged for opam

You can test by cloning this repo and then running

./opam.sh
cd opam
opam install . --verbose --with-test --yes