flambda-backend: Revert "Revert "Refactor Persistent_env to separat…

…e imports from bound names"" (ocaml-flambda#2632)

Revert "Revert "Refactor `Persistent_env` to separate imports from bound name…"

This reverts commit cdbde41.

.depend

@@ -1321,35 +1321,43 @@ typing/patterns.cmi : \
     parsing/asttypes.cmi
 typing/persistent_env.cmo : \
     utils/warnings.cmi \
+    typing/subst.cmi \
+    typing/shape.cmi \
     utils/misc.cmi \
     parsing/location.cmi \
     utils/load_path.cmi \
     utils/lazy_backtrack.cmi \
     utils/import_info.cmi \
+    typing/ident.cmi \
     utils/consistbl.cmi \
     utils/compilation_unit.cmi \
     file_formats/cmi_format.cmi \
     utils/clflags.cmi \
     typing/persistent_env.cmi
 typing/persistent_env.cmx : \
     utils/warnings.cmx \
+    typing/subst.cmx \
+    typing/shape.cmx \
     utils/misc.cmx \
     parsing/location.cmx \
     utils/load_path.cmx \
     utils/lazy_backtrack.cmx \
     utils/import_info.cmx \
+    typing/ident.cmx \
     utils/consistbl.cmx \
     utils/compilation_unit.cmx \
     file_formats/cmi_format.cmx \
     utils/clflags.cmx \
     typing/persistent_env.cmi
 typing/persistent_env.cmi : \
     typing/subst.cmi \
+    typing/shape.cmi \
     utils/misc.cmi \
     parsing/location.cmi \
     utils/load_path.cmi \
     utils/lazy_backtrack.cmi \
     utils/import_info.cmi \
+    typing/ident.cmi \
     utils/consistbl.cmi \
     utils/compilation_unit.cmi \
     file_formats/cmi_format.cmi

testsuite/tests/templates/basic/bad_param_impl.ml

@@ -9,8 +9,6 @@
  ocamlc_byte_exit_status = "2";
  compiler_output = "bad_param_impl.output";
  ocamlc.byte;
- reason = "error broken, will be fixed by #1764";
- skip;
  compiler_reference = "bad_param_impl.reference";
  check-ocamlc.byte-output;
 *)

testsuite/tests/templates/basic/test.ml

@@ -8,8 +8,6 @@
  compiler_output = "bad_ref_direct.output";
  ocamlc_byte_exit_status = "2";
  ocamlc.byte;
- reason = "correct error message not yet implemented";
- skip;
  compiler_reference = "bad_ref_direct.reference";
  check-ocamlc.byte-output;
 *)

typing/env.ml

@@ -173,7 +173,7 @@ let map_summary f = function
   | Env_value_unbound (s, u, r) -> Env_value_unbound (f s, u, r)
   | Env_module_unbound (s, u, r) -> Env_module_unbound (f s, u, r)
 
-type address =
+type address = Persistent_env.address =
   | Aunit of Compilation_unit.t
   | Alocal of Ident.t
   | Adot of address * int
@@ -953,34 +953,24 @@ let components_of_module ~alerts ~uid env ps path addr mty shape =
     }
   }
 
-let read_sign_of_cmi { Persistent_env.Persistent_signature.cmi; _ } =
-  let name =
-    match cmi.cmi_kind with
-    | Normal { cmi_impl } -> cmi_impl
-    | Parameter -> Misc.fatal_error "Unsupported import of parameter module"
-  in
-  let sign = cmi.cmi_sign in
-  let flags = cmi.cmi_flags in
-  let id = Ident.create_persistent (Compilation_unit.name_as_string name) in
+let read_sign_of_cmi sign name uid ~shape ~address:addr ~flags =
+  let id = Ident.create_persistent (Compilation_unit.Name.to_string name) in
   let path = Pident id in
   let alerts =
     List.fold_left (fun acc -> function Alerts s -> s | _ -> acc)
       Misc.Stdlib.String.Map.empty
       flags
   in
-  let sign = Subst.Lazy.signature Make_local Subst.identity sign in
   let md =
     { Subst.Lazy.md_type = Mty_signature sign;
       md_loc = Location.none;
       md_attributes = [];
-      md_uid = Uid.of_compilation_unit_id name;
+      md_uid = uid;
     }
   in
-  let mda_address = Lazy_backtrack.create_forced (Aunit name) in
+  let mda_address = Lazy_backtrack.create_forced addr in
   let mda_declaration = md in
-  let mda_shape =
-    Shape.for_persistent_unit (name |> Compilation_unit.full_path_as_string)
-  in
+  let mda_shape = shape in
   let mda_components =
     let mty = md.md_type in
     components_of_module ~alerts ~uid:md.md_uid
@@ -1016,7 +1006,7 @@ let check_pers_mod ~loc name =
   Persistent_env.check !persistent_env read_sign_of_cmi ~loc name
 
 let crc_of_unit name =
-  Persistent_env.crc_of_unit !persistent_env read_sign_of_cmi name
+  Persistent_env.crc_of_unit !persistent_env name
 
 let is_imported_opaque modname =
   Persistent_env.is_imported_opaque !persistent_env modname
@@ -2646,13 +2636,8 @@ let open_signature
 
 (* Read a signature from a file *)
 let read_signature modname filename ~add_binding =
-  let mda =
-    read_pers_mod modname filename ~add_binding
-  in
-  let md = Subst.Lazy.force_module_decl mda.mda_declaration in
-  match md.md_type with
-  | Mty_signature sg -> sg
-  | Mty_ident _ | Mty_functor _ | Mty_alias _ | Mty_strengthen _ -> assert false
+  let mty = read_pers_mod modname filename ~add_binding in
+  Subst.Lazy.force_signature mty
 
 let is_identchar_latin1 = function
   | 'A'..'Z' | 'a'..'z' | '_' | '\192'..'\214' | '\216'..'\246'