undefined_symbol_ctypes

$ make
ocaml setup.ml -build
W: Cannot find source file matching module 'Vw_bindings' in library vw.
W: Use InterfacePatterns or ImplementationPatterns to define this file with feature "source_patterns".
W: Cannot find source file matching module 'Vw_generated' in library vw.
W: Use InterfacePatterns or ImplementationPatterns to define this file with feature "source_patterns".
Finished, 0 targets (0 cached) in 00:00:00.
+ /Users/travisbrady/.opam/4.03.0/bin/ocamlfind ocamlopt -g -I lib -linkpkg -package ctypes -package ctypes.foreign -package ctypes.stubs -package threads -thread lib/vw.cmxa examples/simple.cmx -o examples/simple.native
Undefined symbols for architecture x86_64:
  "_VW_Initialize", referenced from:
      _vw_1_VW_Initialize in libvw_stubs.a(vw_stubs.o)
     (maybe you meant: _vw_1_VW_Initialize)
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
File "caml_startup", line 1:
Error: Error during linking
Command exited with code 2.
Compilation unsuccessful after building 28 targets (26 cached) in 00:00:00.
E: Failure("Command ''/Users/travisbrady/.opam/4.03.0/bin/ocamlbuild' stubs/vw_stubgen.native lib/libvw_stubs.a lib/dllvw_stubs.so lib/vw.cma lib/vw.cmxa lib/vw.a lib/vw.cmxs examples/simple.native -tag debug' terminated with error code 10")
make: *** [build] Error 1