(* Step 3: the project's own C stubs, in the same link as the compiler.
   lib/dynload_stubs.c is taken verbatim from 9e0ae3a (the unmerged dlopen
   branch) -- it is the only C the compiler itself is built from, and it is the
   case that -output-complete-obj has to carry through. *)

external dl_open : string -> nativeint = "flan_dl_open"
external dl_sym : nativeint -> string -> nativeint = "flan_dl_sym"
external mem_alloc : int -> nativeint = "flan_mem_alloc"
external mem_free : nativeint -> unit = "flan_mem_free"
external poke_i64 : nativeint -> int -> int64 -> unit = "flan_poke_i64"
external peek_i64 : nativeint -> int -> int64 = "flan_peek_i64"

let () =
  Callback.register "spike_stubs" (fun () ->
      (* peek/poke: the raw memory the marshaller lays a Form image out in. *)
      let p = mem_alloc 64 in
      poke_i64 p 8 0xfeedfacedeadbeefL;
      let got = peek_i64 p 8 in
      mem_free p;
      (* dlopen from inside the embedded runtime, on the process's own image. *)
      let h = dl_open "libm.so.6" in
      let s = dl_sym h "sqrt" in
      Printf.sprintf "peek/poke %s; dlopen+dlsym %s"
        (if got = 0xfeedfacedeadbeefL then "ok" else "WRONG")
        (if s <> 0n then "ok" else "WRONG"));
  ignore dl_open