Install the base packages when building the system compiler descripti…

…on file

src/client.ml

@@ -320,9 +320,11 @@ let substitute_string t s =
 
 let create_default_compiler_description t =
   let ocaml_version = OCaml_V.of_string Globals.default_compiler_version in
+  let mk name = ((name,None),None) in
   let f =
     File.Comp.create_preinstalled
       ocaml_version
+      [ mk "base-thread"; mk "base-unix"; mk "base-bigarray"; mk "base-threads" ]
       [ ("CAML_LD_LIBRARY_PATH", "+=", Dirname.to_string (Path.C.stublibs t.compiler))] in
   let comp = Path.G.compiler t.global ocaml_version in
   File.Comp.write comp f

src/file.ml

@@ -829,8 +829,8 @@ module Comp = struct
     env       = [];
   }
 
-  let create_preinstalled name env =
-    { empty with name; preinstalled = true; env }
+  let create_preinstalled name packages env =
+    { empty with name; preinstalled = true; packages; env }
 
   let s_name      = "name"
   let s_src       = "src"

src/file.mli

@@ -168,7 +168,8 @@ module Comp: sig
   include IO_FILE
 
   (** Create a pre-installed compiler description file *)
-  val create_preinstalled: OCaml_V.t -> (string * string * string) list -> t
+  val create_preinstalled:
+    OCaml_V.t -> and_formula -> (string * string * string) list -> t
 
   (** Is it a pre-installed compiler description file *)
   val preinstalled: t -> bool