diff --git a/compiler/core/js_of_lam_block.ml b/compiler/core/js_of_lam_block.ml
index 9bb1a0b2c3..850e8ad2f9 100644
--- a/compiler/core/js_of_lam_block.ml
+++ b/compiler/core/js_of_lam_block.ml
@@ -33,7 +33,7 @@ let make_block mutable_flag (tag_info : Lam_tag_info.t) tag args =
 
 let field (field_info : Lam_compat.field_dbg_info) e (i : int32) =
   match field_info with
-  | Fld_tuple | Fld_array ->
+  | Fld_tuple ->
     E.array_index_by_int ?comment:(Lam_compat.str_of_field_info field_info) e i
   | Fld_poly_var_content -> E.poly_var_value_access e
   | Fld_poly_var_tag -> E.poly_var_tag_access e
diff --git a/compiler/core/lam_analysis.ml b/compiler/core/lam_analysis.ml
index a95b382ca2..9bd4581ef4 100644
--- a/compiler/core/lam_analysis.ml
+++ b/compiler/core/lam_analysis.ml
@@ -97,8 +97,7 @@ let rec no_side_effects (lam : Lam.t) : bool =
     (* TODO *)
     | Praw_js_code _
     (* byte swap *)
-    | Parraysets | Parraysetu | Poffsetref _ | Praise | Plazyforce | Psetfield _
-      ->
+    | Parraysets | Parraysetu | Poffsetref _ | Praise | Psetfield _ ->
       false)
   | Llet (_, _, arg, body) -> no_side_effects arg && no_side_effects body
   | Lswitch (_, _) -> false
diff --git a/compiler/core/lam_compat.ml b/compiler/core/lam_compat.ml
index bf7b08157e..a652d74ca4 100644
--- a/compiler/core/lam_compat.ml
+++ b/compiler/core/lam_compat.ml
@@ -73,11 +73,10 @@ type field_dbg_info = Lambda.field_dbg_info =
   | Fld_extension
   | Fld_variant
   | Fld_cons
-  | Fld_array
 
 let str_of_field_info (x : field_dbg_info) : string option =
   match x with
-  | Fld_array | Fld_extension | Fld_variant | Fld_cons | Fld_poly_var_tag
+  | Fld_extension | Fld_variant | Fld_cons | Fld_poly_var_tag
   | Fld_poly_var_content | Fld_tuple ->
     None
   | Fld_record {name; _}
diff --git a/compiler/core/lam_compat.mli b/compiler/core/lam_compat.mli
index 4a1c94217e..4d67d95242 100644
--- a/compiler/core/lam_compat.mli
+++ b/compiler/core/lam_compat.mli
@@ -37,7 +37,6 @@ type field_dbg_info = Lambda.field_dbg_info =
   | Fld_extension
   | Fld_variant
   | Fld_cons
-  | Fld_array
 
 val str_of_field_info : field_dbg_info -> string option
 
diff --git a/compiler/core/lam_compile_primitive.ml b/compiler/core/lam_compile_primitive.ml
index c33a329283..6f3f16686a 100644
--- a/compiler/core/lam_compile_primitive.ml
+++ b/compiler/core/lam_compile_primitive.ml
@@ -605,13 +605,3 @@ let translate output_prefix loc (cxt : Lam_compile_context.t)
     match args with
     | [e1] -> E.runtime_call Primitive_modules.hash "hash_final_mix" args
     | _ -> assert false)
-  | Plazyforce
-  (* FIXME: we don't inline lazy force or at least
-     let buckle handle it
-  *)
-  (* let parm = Ident.create "prim" in
-     Lfunction(Curried, [parm],
-               Matching.inline_lazy_force (Lvar parm) Location.none)
-     It is inlined, this should not appear here *)
-    ->
-    assert false
diff --git a/compiler/core/lam_constant_convert.ml b/compiler/core/lam_constant_convert.ml
index ad0e7de05a..938977d581 100644
--- a/compiler/core/lam_constant_convert.ml
+++ b/compiler/core/lam_constant_convert.ml
@@ -63,7 +63,6 @@ let rec convert_constant (const : Lambda.structured_constant) : Lam_constant.t =
       if Ext_string.is_valid_hash_number name then
         Const_int {i = Ext_string.hash_number_as_i32_exn name; comment = None}
       else Const_pointer name)
-  | Const_float_array s -> assert false
   | Const_immstring s -> Const_string {s; unicode = false}
   | Const_block (t, xs) -> (
     let tag = Lambda.tag_of_tag_info t in
diff --git a/compiler/core/lam_convert.ml b/compiler/core/lam_convert.ml
index 7c877cefb1..dae5b351d9 100644
--- a/compiler/core/lam_convert.ml
+++ b/compiler/core/lam_convert.ml
@@ -229,7 +229,6 @@ let lam_prim ~primitive:(p : Lambda.primitive) ~args loc : Lam.t =
   | Pfield (id, info) -> prim ~primitive:(Pfield (id, info)) ~args loc
   | Psetfield (id, info) -> prim ~primitive:(Psetfield (id, info)) ~args loc
   | Pduprecord -> prim ~primitive:Pduprecord ~args loc
-  | Plazyforce -> prim ~primitive:Plazyforce ~args loc
   | Praise _ -> prim ~primitive:Praise ~args loc
   | Pobjcomp x -> prim ~primitive:(Pobjcomp x) ~args loc
   | Pobjorder -> prim ~primitive:Pobjorder ~args loc
@@ -248,8 +247,8 @@ let lam_prim ~primitive:(p : Lambda.primitive) ~args loc : Lam.t =
   | Paddint -> prim ~primitive:Paddint ~args loc
   | Psubint -> prim ~primitive:Psubint ~args loc
   | Pmulint -> prim ~primitive:Pmulint ~args loc
-  | Pdivint _is_safe (*FIXME*) -> prim ~primitive:Pdivint ~args loc
-  | Pmodint _is_safe (*FIXME*) -> prim ~primitive:Pmodint ~args loc
+  | Pdivint -> prim ~primitive:Pdivint ~args loc
+  | Pmodint -> prim ~primitive:Pmodint ~args loc
   | Pandint -> prim ~primitive:Pandint ~args loc
   | Porint -> prim ~primitive:Porint ~args loc
   | Pxorint -> prim ~primitive:Pxorint ~args loc
@@ -334,11 +333,6 @@ let lam_prim ~primitive:(p : Lambda.primitive) ~args loc : Lam.t =
   | Pjs_fn_make arity -> prim ~primitive:(Pjs_fn_make arity) ~args loc
   | Pjs_fn_make_unit -> prim ~primitive:Pjs_fn_make_unit ~args loc
   | Pjs_fn_method -> prim ~primitive:Pjs_fn_method ~args loc
-  | Pjs_unsafe_downgrade ->
-    let primitive : Lam_primitive.t =
-      Pjs_unsafe_downgrade {name = Ext_string.empty; setter = false}
-    in
-    prim ~primitive ~args loc
 
 (* Does not exist since we compile array in js backend unlike native backend *)
 
diff --git a/compiler/core/lam_primitive.ml b/compiler/core/lam_primitive.ml
index 21cedb23e5..9bd68d2975 100644
--- a/compiler/core/lam_primitive.ml
+++ b/compiler/core/lam_primitive.ml
@@ -40,8 +40,6 @@ type t =
   | Psetfield of int * Lam_compat.set_field_dbg_info
   (* could have field info at least for record *)
   | Pduprecord
-  (* Force lazy values *)
-  | Plazyforce
   (* External call *)
   | Pjs_call of {
       prim_name: string;
@@ -222,10 +220,10 @@ let eq_primitive_approx (lhs : t) (rhs : t) =
   | Pjs_apply | Pjs_runtime_apply | Pval_from_option | Pval_from_option_not_nest
   | Pundefined_to_opt | Pnull_to_opt | Pnull_undefined_to_opt | Pis_null
   | Pis_not_none | Psome | Psome_not_nest | Pis_undefined | Pis_null_undefined
-  | Pimport | Ptypeof | Pfn_arity | Plazyforce | Pis_poly_var_block | Pdebugger
-  | Pinit_mod | Pupdate_mod | Pduprecord | Pmakearray | Parraylength
-  | Parrayrefu | Parraysetu | Parrayrefs | Parraysets | Pjs_fn_make_unit
-  | Pjs_fn_method | Phash | Phash_mixstring | Phash_mixint | Phash_finalmix ->
+  | Pimport | Ptypeof | Pfn_arity | Pis_poly_var_block | Pdebugger | Pinit_mod
+  | Pupdate_mod | Pduprecord | Pmakearray | Parraylength | Parrayrefu
+  | Parraysetu | Parrayrefs | Parraysets | Pjs_fn_make_unit | Pjs_fn_method
+  | Phash | Phash_mixstring | Phash_mixint | Phash_finalmix ->
     rhs = lhs
   | Pcreate_extension a -> (
     match rhs with
diff --git a/compiler/core/lam_primitive.mli b/compiler/core/lam_primitive.mli
index 4f358b525a..164f66a5be 100644
--- a/compiler/core/lam_primitive.mli
+++ b/compiler/core/lam_primitive.mli
@@ -36,7 +36,6 @@ type t =
   | Pfield of int * Lambda.field_dbg_info
   | Psetfield of int * Lambda.set_field_dbg_info
   | Pduprecord
-  | Plazyforce
   | Pjs_call of {
       (* Location.t *  [loc] is passed down *)
       prim_name: string;
diff --git a/compiler/core/lam_print.ml b/compiler/core/lam_print.ml
index 17c18d6108..43c99edc88 100644
--- a/compiler/core/lam_print.ml
+++ b/compiler/core/lam_print.ml
@@ -82,7 +82,6 @@ let primitive ppf (prim : Lam_primitive.t) =
     let instr = "setfield " in
     fprintf ppf "%s%i" instr n
   | Pduprecord -> fprintf ppf "duprecord"
-  | Plazyforce -> fprintf ppf "force"
   | Pjs_call {prim_name} -> fprintf ppf "%s[js]" prim_name
   | Pjs_object_create _ -> fprintf ppf "[js.obj]"
   | Praise -> fprintf ppf "raise"
diff --git a/compiler/ml/datarepr.ml b/compiler/ml/datarepr.ml
index 9e37269deb..b1c69741cf 100644
--- a/compiler/ml/datarepr.ml
+++ b/compiler/ml/datarepr.ml
@@ -101,11 +101,10 @@ let constructor_has_optional_shape
 
 let constructor_descrs ty_path decl cstrs =
   let ty_res = newgenconstr ty_path decl.type_params in
-  let num_consts = ref 0 and num_nonconsts = ref 0 and num_normal = ref 0 in
+  let num_consts = ref 0 and num_nonconsts = ref 0 in
   List.iter
-    (fun {cd_args; cd_res; _} ->
-      if cd_args = Cstr_tuple [] then incr num_consts else incr num_nonconsts;
-      if cd_res = None then incr num_normal)
+    (fun {cd_args; _} ->
+      if cd_args = Cstr_tuple [] then incr num_consts else incr num_nonconsts)
     cstrs;
   let rec describe_constructors idx_const idx_nonconst = function
     | [] -> []
@@ -154,7 +153,6 @@ let constructor_descrs ty_path decl cstrs =
           cstr_tag = tag;
           cstr_consts = !num_consts;
           cstr_nonconsts = !num_nonconsts;
-          cstr_normal = !num_normal;
           cstr_private = decl.type_private;
           cstr_generalized = cd_res <> None;
           cstr_loc = cd_loc;
@@ -208,7 +206,6 @@ let extension_descr path_ext ext =
     cstr_consts = -1;
     cstr_nonconsts = -1;
     cstr_private = ext.ext_private;
-    cstr_normal = -1;
     cstr_generalized = ext.ext_ret_type <> None;
     cstr_loc = ext.ext_loc;
     cstr_attributes = ext.ext_attributes;
diff --git a/compiler/ml/env.ml b/compiler/ml/env.ml
index 1547d3450b..a40a83bed0 100644
--- a/compiler/ml/env.ml
+++ b/compiler/ml/env.ml
@@ -57,7 +57,6 @@ let prefixed_sg = Hashtbl.create 113
 type error =
   | Illegal_renaming of string * string * string
   | Inconsistent_import of string * string * string
-  | Need_recursive_types of string * string
   | Missing_module of Location.t * Path.t * Path.t
   | Illegal_value_name of Location.t * string
 
@@ -147,8 +146,6 @@ type summary =
   | Env_extension of summary * Ident.t * extension_constructor
   | Env_module of summary * Ident.t * module_declaration
   | Env_modtype of summary * Ident.t * modtype_declaration
-  | Env_class of unit
-  | Env_cltype of unit
   | Env_open of summary * Path.t
   | Env_functor_arg of summary * Ident.t
   | Env_constraints of summary * type_declaration PathMap.t
@@ -732,8 +729,6 @@ let check_pers_struct name =
           " %a@ contains the compiled interface for @ %s when %s was expected"
           Location.print_filename filename ps_name name
       | Inconsistent_import _ -> assert false
-      | Need_recursive_types (name, _) ->
-        Format.sprintf "%s uses recursive types" name
       | Missing_module _ -> assert false
       | Illegal_value_name _ -> assert false
     in
@@ -2129,10 +2124,6 @@ let report_error ppf = function
       "@[<hov>The files %a@ and %a@ make inconsistent assumptions@ over \
        interface %s@]"
       Location.print_filename source1 Location.print_filename source2 name
-  | Need_recursive_types (import, export) ->
-    fprintf ppf
-      "@[<hov>Unit %s imports from %s, which uses recursive types.@ %s@]" export
-      import "The compilation flag -rectypes is required"
   | Missing_module (_, path1, path2) ->
     fprintf ppf "@[@[<hov>";
     if Path.same path1 path2 then
diff --git a/compiler/ml/env.mli b/compiler/ml/env.mli
index 8c178452c5..c36a0aa052 100644
--- a/compiler/ml/env.mli
+++ b/compiler/ml/env.mli
@@ -27,8 +27,6 @@ type summary =
   | Env_extension of summary * Ident.t * extension_constructor
   | Env_module of summary * Ident.t * module_declaration
   | Env_modtype of summary * Ident.t * modtype_declaration
-  | Env_class of unit
-  | Env_cltype of unit
   | Env_open of summary * Path.t
   | Env_functor_arg of summary * Ident.t
   | Env_constraints of summary * type_declaration PathMap.t
@@ -239,7 +237,6 @@ val env_of_only_summary : (summary -> Subst.t -> t) -> t -> t
 type error =
   | Illegal_renaming of string * string * string
   | Inconsistent_import of string * string * string
-  | Need_recursive_types of string * string
   | Missing_module of Location.t * Path.t * Path.t
   | Illegal_value_name of Location.t * string
 
diff --git a/compiler/ml/error_message_utils.ml b/compiler/ml/error_message_utils.ml
index 1fa8fe7256..c80295c248 100644
--- a/compiler/ml/error_message_utils.ml
+++ b/compiler/ml/error_message_utils.ml
@@ -5,7 +5,6 @@ type type_clash_statement = FunctionCall
 type type_clash_context =
   | SetRecordField
   | ArrayValue
-  | FunctionReturn
   | MaybeUnwrapOption
   | IfCondition
   | IfReturn
@@ -53,8 +52,6 @@ let error_expected_type_text ppf type_clash_context =
     fprintf ppf
       "But it's being used with the @{<info>%s@} operator, which works on:"
       operator
-  | Some FunctionReturn ->
-    fprintf ppf "But this function is expecting you to return:"
   | Some StringConcat -> fprintf ppf "But string concatenation is expecting:"
   | _ -> fprintf ppf "But it's expected to have type:"
 
diff --git a/compiler/ml/lambda.ml b/compiler/ml/lambda.ml
index 89e7f6f477..809c1164a7 100644
--- a/compiler/ml/lambda.ml
+++ b/compiler/ml/lambda.ml
@@ -125,7 +125,6 @@ type field_dbg_info =
   | Fld_extension
   | Fld_variant
   | Fld_cons
-  | Fld_array
 
 let fld_record (lbl : label) =
   Fld_record
@@ -164,8 +163,6 @@ let fld_record_extension_set (lbl : label) =
 
 type immediate_or_pointer = Immediate | Pointer
 
-type is_safe = Safe | Unsafe
-
 type primitive =
   | Pidentity
   | Pignore
@@ -183,8 +180,6 @@ type primitive =
   | Pfield of int * field_dbg_info
   | Psetfield of int * set_field_dbg_info
   | Pduprecord
-  (* Force lazy values *)
-  | Plazyforce
   (* External call *)
   | Pccall of Primitive.description
   (* Exceptions *)
@@ -209,8 +204,8 @@ type primitive =
   | Paddint
   | Psubint
   | Pmulint
-  | Pdivint of is_safe
-  | Pmodint of is_safe
+  | Pdivint
+  | Pmodint
   | Pandint
   | Porint
   | Pxorint
@@ -310,13 +305,12 @@ type primitive =
   | Pjs_fn_make of int
   | Pjs_fn_make_unit
   | Pjs_fn_method
-  | Pjs_unsafe_downgrade
 
 and comparison = Ceq | Cneq | Clt | Cgt | Cle | Cge
 
 and value_kind = Pgenval
 
-and raise_kind = Raise_regular | Raise_reraise | Raise_notrace
+and raise_kind = Raise_regular | Raise_reraise
 
 type pointer_info =
   | Pt_constructor of {
@@ -334,7 +328,6 @@ type structured_constant =
   | Const_base of Asttypes.constant
   | Const_pointer of int * pointer_info
   | Const_block of tag_info * structured_constant list
-  | Const_float_array of string list
   | Const_immstring of string
   | Const_false
   | Const_true
@@ -507,16 +500,6 @@ let name_lambda strict arg fn =
     let id = Ident.create "let" in
     Llet (strict, Pgenval, id, arg, fn id)
 
-let name_lambda_list args fn =
-  let rec name_list names = function
-    | [] -> fn (List.rev names)
-    | (Lvar _ as arg) :: rem -> name_list (arg :: names) rem
-    | arg :: rem ->
-      let id = Ident.create "let" in
-      Llet (Strict, Pgenval, id, arg, name_list (Lvar id :: names) rem)
-  in
-  name_list [] args
-
 let iter_opt f = function
   | None -> ()
   | Some e -> f e
@@ -650,16 +633,6 @@ let transl_value_path ?(loc = Location.none) env path =
 
 let transl_extension_path = transl_value_path
 
-(* compatibility alias, deprecated in the .mli *)
-(* Compile a sequence of expressions *)
-
-let rec make_sequence fn = function
-  | [] -> lambda_unit
-  | [x] -> fn x
-  | x :: rem ->
-    let lam = fn x in
-    Lsequence (lam, make_sequence fn rem)
-
 (* Apply a substitution to a lambda-term.
    Assumes that the bound variables of the lambda-term do not
    belong to the domain of the substitution.
@@ -713,56 +686,6 @@ let subst_lambda s lam =
   in
   subst lam
 
-let rec map f lam =
-  let lam =
-    match lam with
-    | Lvar _ -> lam
-    | Lconst _ -> lam
-    | Lapply {ap_func; ap_args; ap_loc; ap_inlined} ->
-      Lapply
-        {
-          ap_func = map f ap_func;
-          ap_args = List.map (map f) ap_args;
-          ap_loc;
-          ap_inlined;
-        }
-    | Lfunction {params; body; attr; loc} ->
-      Lfunction {params; body = map f body; attr; loc}
-    | Llet (str, k, v, e1, e2) -> Llet (str, k, v, map f e1, map f e2)
-    | Lletrec (idel, e2) ->
-      Lletrec (List.map (fun (v, e) -> (v, map f e)) idel, map f e2)
-    | Lprim (p, el, loc) -> Lprim (p, List.map (map f) el, loc)
-    | Lswitch (e, sw, loc) ->
-      Lswitch
-        ( map f e,
-          {
-            sw_numconsts = sw.sw_numconsts;
-            sw_consts = List.map (fun (n, e) -> (n, map f e)) sw.sw_consts;
-            sw_numblocks = sw.sw_numblocks;
-            sw_blocks = List.map (fun (n, e) -> (n, map f e)) sw.sw_blocks;
-            sw_failaction = Misc.may_map (map f) sw.sw_failaction;
-            sw_names = sw.sw_names;
-          },
-          loc )
-    | Lstringswitch (e, sw, default, loc) ->
-      Lstringswitch
-        ( map f e,
-          List.map (fun (s, e) -> (s, map f e)) sw,
-          Misc.may_map (map f) default,
-          loc )
-    | Lstaticraise (i, args) -> Lstaticraise (i, List.map (map f) args)
-    | Lstaticcatch (body, id, handler) ->
-      Lstaticcatch (map f body, id, map f handler)
-    | Ltrywith (e1, v, e2) -> Ltrywith (map f e1, v, map f e2)
-    | Lifthenelse (e1, e2, e3) -> Lifthenelse (map f e1, map f e2, map f e3)
-    | Lsequence (e1, e2) -> Lsequence (map f e1, map f e2)
-    | Lwhile (e1, e2) -> Lwhile (map f e1, map f e2)
-    | Lfor (v, e1, e2, dir, e3) -> Lfor (v, map f e1, map f e2, dir, map f e3)
-    | Lassign (v, e) -> Lassign (v, map f e)
-    | Lsend (k, o, loc) -> Lsend (k, map f o, loc)
-  in
-  f lam
-
 (* To let-bind expressions to variables *)
 
 let bind str var exp body =
@@ -770,26 +693,9 @@ let bind str var exp body =
   | Lvar var' when Ident.same var var' -> body
   | _ -> Llet (str, Pgenval, var, exp, body)
 
-and commute_comparison = function
-  | Ceq -> Ceq
-  | Cneq -> Cneq
-  | Clt -> Cgt
-  | Cle -> Cge
-  | Cgt -> Clt
-  | Cge -> Cle
-
-and negate_comparison = function
-  | Ceq -> Cneq
-  | Cneq -> Ceq
-  | Clt -> Cge
-  | Cle -> Cgt
-  | Cgt -> Cle
-  | Cge -> Clt
-
 let raise_kind = function
   | Raise_regular -> "raise"
   | Raise_reraise -> "reraise"
-  | Raise_notrace -> "raise_notrace"
 
 let lam_of_loc kind loc =
   let loc_start = loc.Location.loc_start in
@@ -821,5 +727,3 @@ let lam_of_loc kind loc =
     in
     Lconst (Const_immstring loc)
   | Loc_LINE -> Lconst (Const_base (Const_int lnum))
-
-let reset () = raise_count := 0
diff --git a/compiler/ml/lambda.mli b/compiler/ml/lambda.mli
index cf163b461d..aecdec146f 100644
--- a/compiler/ml/lambda.mli
+++ b/compiler/ml/lambda.mli
@@ -94,7 +94,6 @@ type field_dbg_info =
   | Fld_extension
   | Fld_variant
   | Fld_cons
-  | Fld_array
 
 val fld_record : Types.label_description -> field_dbg_info
 
@@ -118,7 +117,6 @@ val fld_record_inline_set : Types.label_description -> set_field_dbg_info
 val fld_record_extension_set : Types.label_description -> set_field_dbg_info
 
 type immediate_or_pointer = Immediate | Pointer
-type is_safe = Safe | Unsafe
 
 type pointer_info =
   | Pt_constructor of {
@@ -149,8 +147,6 @@ type primitive =
   | Pfield of int * field_dbg_info
   | Psetfield of int * set_field_dbg_info
   | Pduprecord
-  (* Force lazy values *)
-  | Plazyforce
   (* External call *)
   | Pccall of Primitive.description
   (* Exceptions *)
@@ -175,8 +171,8 @@ type primitive =
   | Paddint
   | Psubint
   | Pmulint
-  | Pdivint of is_safe
-  | Pmodint of is_safe
+  | Pdivint
+  | Pmodint
   | Pandint
   | Porint
   | Pxorint
@@ -276,19 +272,17 @@ type primitive =
   | Pjs_fn_make of int
   | Pjs_fn_make_unit
   | Pjs_fn_method
-  | Pjs_unsafe_downgrade
 
 and comparison = Ceq | Cneq | Clt | Cgt | Cle | Cge
 
 and value_kind = Pgenval
 
-and raise_kind = Raise_regular | Raise_reraise | Raise_notrace
+and raise_kind = Raise_regular | Raise_reraise
 
 type structured_constant =
   | Const_base of constant
   | Const_pointer of int * pointer_info
   | Const_block of tag_info * structured_constant list
-  | Const_float_array of string list
   | Const_immstring of string
   | Const_false
   | Const_true
@@ -386,7 +380,6 @@ val lambda_assert_false : lambda
 val lambda_unit : lambda
 val lambda_module_alias : lambda
 val name_lambda : let_kind -> lambda -> (Ident.t -> lambda) -> lambda
-val name_lambda_list : lambda list -> (lambda list -> lambda) -> lambda
 
 val iter : (lambda -> unit) -> lambda -> unit
 module IdentSet : Set.S with type elt = Ident.t
@@ -398,15 +391,9 @@ val transl_module_path : ?loc:Location.t -> Env.t -> Path.t -> lambda
 val transl_value_path : ?loc:Location.t -> Env.t -> Path.t -> lambda
 val transl_extension_path : ?loc:Location.t -> Env.t -> Path.t -> lambda
 
-val make_sequence : ('a -> lambda) -> 'a list -> lambda
-
 val subst_lambda : lambda Ident.tbl -> lambda -> lambda
-val map : (lambda -> lambda) -> lambda -> lambda
 val bind : let_kind -> Ident.t -> lambda -> lambda -> lambda
 
-val commute_comparison : comparison -> comparison
-val negate_comparison : comparison -> comparison
-
 val default_function_attribute : function_attribute
 
 (***********************)
@@ -429,5 +416,3 @@ val patch_guarded : lambda -> lambda -> lambda
 
 val raise_kind : raise_kind -> string
 val lam_of_loc : loc_kind -> Location.t -> lambda
-
-val reset : unit -> unit
diff --git a/compiler/ml/primitive.ml b/compiler/ml/primitive.ml
index f776eb29df..602cb22089 100644
--- a/compiler/ml/primitive.ml
+++ b/compiler/ml/primitive.ml
@@ -18,8 +18,6 @@
 open Misc
 open Parsetree
 
-type boxed_integer = Pbigint | Pint32 | Pint64
-
 type description = {
   prim_name: string; (* Name of primitive  or C function *)
   prim_arity: int; (* Number of arguments *)
@@ -32,24 +30,6 @@ type description = {
 let coerce : (description -> description -> bool) ref =
   ref (fun (p1 : description) (p2 : description) -> p1 = p2)
 
-let simple ~name ~arity ~alloc =
-  {
-    prim_name = name;
-    prim_arity = arity;
-    prim_alloc = alloc;
-    prim_native_name = "";
-    prim_from_constructor = false;
-  }
-
-let make ~name ~alloc ~native_name ~arity =
-  {
-    prim_name = name;
-    prim_arity = arity;
-    prim_alloc = alloc;
-    prim_native_name = native_name;
-    prim_from_constructor = false;
-  }
-
 let parse_declaration valdecl ~arity ~from_constructor =
   let name, native_name =
     match valdecl.pval_prim with
@@ -73,8 +53,3 @@ let print p osig_val_decl =
     else [p.prim_name]
   in
   {osig_val_decl with oval_prims = prims; oval_attributes = []}
-
-let native_name p =
-  if p.prim_native_name <> "" then p.prim_native_name else p.prim_name
-
-let byte_name p = p.prim_name
diff --git a/compiler/ml/primitive.mli b/compiler/ml/primitive.mli
index dbd4cc310c..9166ae1a5c 100644
--- a/compiler/ml/primitive.mli
+++ b/compiler/ml/primitive.mli
@@ -15,8 +15,6 @@
 
 (* Description of primitive functions *)
 
-type boxed_integer = Pbigint | Pint32 | Pint64
-
 type description = private {
   prim_name: string; (* Name of primitive  or C function *)
   prim_arity: int; (* Number of arguments *)
@@ -28,11 +26,6 @@ type description = private {
 
 (* Invariant [List.length d.prim_native_repr_args = d.prim_arity] *)
 
-val simple : name:string -> arity:int -> alloc:bool -> description
-
-val make :
-  name:string -> alloc:bool -> native_name:string -> arity:int -> description
-
 val parse_declaration :
   Parsetree.value_description ->
   arity:int ->
@@ -41,7 +34,4 @@ val parse_declaration :
 
 val print : description -> Outcometree.out_val_decl -> Outcometree.out_val_decl
 
-val native_name : description -> string
-val byte_name : description -> string
-
 val coerce : (description -> description -> bool) ref
diff --git a/compiler/ml/printlambda.ml b/compiler/ml/printlambda.ml
index 6d4d0cebfe..682e05660a 100644
--- a/compiler/ml/printlambda.ml
+++ b/compiler/ml/printlambda.ml
@@ -39,10 +39,6 @@ let rec struct_const ppf = function
       List.iter (fun sc -> fprintf ppf "@ %a" struct_const sc) scl
     in
     fprintf ppf "@[<1>[%i:@ @[%a%a@]]@]" tag struct_const sc1 sconsts scl
-  | Const_float_array [] -> fprintf ppf "[| |]"
-  | Const_float_array (f1 :: fl) ->
-    let floats ppf fl = List.iter (fun f -> fprintf ppf "@ %s" f) fl in
-    fprintf ppf "@[<1>[|@[%s%a@]|]@]" f1 floats fl
   | Const_false -> fprintf ppf "false"
   | Const_true -> fprintf ppf "true"
 
@@ -87,7 +83,6 @@ let str_of_field_info (fld_info : Lambda.field_dbg_info) =
   | Fld_extension -> "ext"
   | Fld_variant -> "var"
   | Fld_cons -> "cons"
-  | Fld_array -> "[||]"
 let print_taginfo ppf = function
   | Blk_extension -> fprintf ppf "ext"
   | Blk_record_ext {fields = ss} ->
@@ -122,7 +117,6 @@ let primitive ppf = function
   | Pfield (n, fld) -> fprintf ppf "field:%s/%i" (str_of_field_info fld) n
   | Psetfield (n, _) -> fprintf ppf "setfield %i" n
   | Pduprecord -> fprintf ppf "duprecord"
-  | Plazyforce -> fprintf ppf "force"
   | Pccall p -> fprintf ppf "%s" p.prim_name
   | Praise k -> fprintf ppf "%s" (Lambda.raise_kind k)
   | Pobjcomp Ceq -> fprintf ppf "=="
@@ -152,10 +146,8 @@ let primitive ppf = function
   | Paddint -> fprintf ppf "+"
   | Psubint -> fprintf ppf "-"
   | Pmulint -> fprintf ppf "*"
-  | Pdivint Safe -> fprintf ppf "/"
-  | Pdivint Unsafe -> fprintf ppf "/u"
-  | Pmodint Safe -> fprintf ppf "mod"
-  | Pmodint Unsafe -> fprintf ppf "mod_unsafe"
+  | Pdivint -> fprintf ppf "/"
+  | Pmodint -> fprintf ppf "mod"
   | Pandint -> fprintf ppf "and"
   | Porint -> fprintf ppf "or"
   | Pxorint -> fprintf ppf "xor"
@@ -268,7 +260,6 @@ let primitive ppf = function
   | Pjs_fn_make arity -> fprintf ppf "#fn_mk(%d)" arity
   | Pjs_fn_make_unit -> fprintf ppf "#fn_mk_unit"
   | Pjs_fn_method -> fprintf ppf "#fn_method"
-  | Pjs_unsafe_downgrade -> fprintf ppf "#unsafe_downgrade"
 
 let function_attribute ppf {inline; is_a_functor; return_unit} =
   if is_a_functor then fprintf ppf "is_a_functor@ ";
diff --git a/compiler/ml/subst.ml b/compiler/ml/subst.ml
index 0b99cf7949..b439b52f11 100644
--- a/compiler/ml/subst.ml
+++ b/compiler/ml/subst.ml
@@ -389,26 +389,3 @@ and modtype_declaration s decl =
 
 (* For every binding k |-> d of m1, add k |-> f d to m2
    and return resulting merged map. *)
-
-let merge_tbls f m1 m2 = Tbl.fold (fun k d accu -> Tbl.add k (f d) accu) m1 m2
-
-let merge_path_maps f m1 m2 =
-  PathMap.fold (fun k d accu -> PathMap.add k (f d) accu) m1 m2
-
-let type_replacement s = function
-  | Path p -> Path (type_path s p)
-  | Type_function {params; body} ->
-    let params = List.map (typexp s) params in
-    let body = typexp s body in
-    Type_function {params; body}
-
-(* Composition of substitutions:
-     apply (compose s1 s2) x = apply s2 (apply s1 x) *)
-
-let compose s1 s2 =
-  {
-    types = merge_path_maps (type_replacement s2) s1.types s2.types;
-    modules = merge_path_maps (module_path s2) s1.modules s2.modules;
-    modtypes = merge_tbls (modtype s2) s1.modtypes s2.modtypes;
-    for_saving = s1.for_saving || s2.for_saving;
-  }
diff --git a/compiler/ml/subst.mli b/compiler/ml/subst.mli
index 10438bfcb1..62ed5d51ab 100644
--- a/compiler/ml/subst.mli
+++ b/compiler/ml/subst.mli
@@ -57,10 +57,6 @@ val modtype_declaration : t -> modtype_declaration -> modtype_declaration
 val module_declaration : t -> module_declaration -> module_declaration
 val typexp : t -> Types.type_expr -> Types.type_expr
 
-(* Composition of substitutions:
-     apply (compose s1 s2) x = apply s2 (apply s1 x) *)
-val compose : t -> t -> t
-
 (* A forward reference to be filled in ctype.ml. *)
 val ctype_apply_env_empty :
   (type_expr list -> type_expr -> type_expr list -> type_expr) ref
diff --git a/compiler/ml/switch.ml b/compiler/ml/switch.ml
index 6236310e49..9626f060c5 100644
--- a/compiler/ml/switch.ml
+++ b/compiler/ml/switch.ml
@@ -16,7 +16,6 @@
 type 'a shared = Shared of 'a | Single of 'a
 
 type 'a t_store = {
-  act_get: unit -> 'a array;
   act_get_shared: unit -> 'a shared array;
   act_store: 'a -> int;
   act_store_shared: 'a -> int;
@@ -65,7 +64,6 @@ module Store (A : Stored) = struct
           st.map <- AMap.add key (mustshare, i) st.map;
           i)
       | None -> add mustshare act
-    and get () = Array.of_list (List.rev_map (fun (_, act) -> act) st.acts)
     and get_shared () =
       let acts =
         Array.of_list
@@ -85,7 +83,6 @@ module Store (A : Stored) = struct
     {
       act_store = store false;
       act_store_shared = store true;
-      act_get = get;
       act_get_shared = get_shared;
     }
 end
diff --git a/compiler/ml/switch.mli b/compiler/ml/switch.mli
index 8edf18a963..89bce4107d 100644
--- a/compiler/ml/switch.mli
+++ b/compiler/ml/switch.mli
@@ -32,7 +32,6 @@
 type 'a shared = Shared of 'a | Single of 'a
 
 type 'a t_store = {
-  act_get: unit -> 'a array;
   act_get_shared: unit -> 'a shared array;
   act_store: 'a -> int;
   act_store_shared: 'a -> int;
diff --git a/compiler/ml/translcore.ml b/compiler/ml/translcore.ml
index 12f30a0533..03782b95fa 100644
--- a/compiler/ml/translcore.ml
+++ b/compiler/ml/translcore.ml
@@ -274,8 +274,8 @@ let primitives_table =
       ("%addint", Paddint);
       ("%subint", Psubint);
       ("%mulint", Pmulint);
-      ("%divint", Pdivint Safe);
-      ("%modint", Pmodint Safe);
+      ("%divint", Pdivint);
+      ("%modint", Pmodint);
       ("%andint", Pandint);
       ("%orint", Porint);
       ("%xorint", Pxorint);
@@ -447,15 +447,6 @@ let transl_primitive loc p env ty =
     with Not_found -> Pccall p
   in
   match prim with
-  | Plazyforce ->
-    let parm = Ident.create "prim" in
-    Lfunction
-      {
-        params = [parm];
-        body = Matching.inline_lazy_force (Lvar parm) Location.none;
-        loc;
-        attr = default_function_attribute;
-      }
   | Ploc kind -> (
     let lam = lam_of_loc kind loc in
     match p.prim_arity with
@@ -757,8 +748,6 @@ and transl_exp0 (e : Typedtree.expression) : Lambda.lambda =
     | Ploc _, _ -> assert false
     | _, _ -> (
       match (prim, argl) with
-      | Plazyforce, [a] -> wrap (Matching.inline_lazy_force a e.exp_loc)
-      | Plazyforce, _ -> assert false
       | _ -> wrap (Lprim (prim, argl, e.exp_loc))))
   | Texp_apply {funct; args = oargs; partial} ->
     let inlined, funct =
diff --git a/compiler/ml/typecore.ml b/compiler/ml/typecore.ml
index 2217d3c94d..ffbfc0ac42 100644
--- a/compiler/ml/typecore.ml
+++ b/compiler/ml/typecore.ml
@@ -69,7 +69,6 @@ type error =
   | Exception_pattern_below_toplevel
   | Inlined_record_escape
   | Inlined_record_expected
-  | Unrefuted_pattern of pattern
   | Invalid_extension_constructor_payload
   | Not_an_extension_constructor
   | Literal_overflow of string
@@ -1997,19 +1996,6 @@ let generalizable level ty =
     false
 
 (* Helpers for packaged modules. *)
-let create_package_type loc env (p, l) =
-  let s = !Typetexp.transl_modtype_longident loc env p in
-  let fields =
-    List.map
-      (fun (name, ct) -> (name, Typetexp.transl_simple_type env false ct))
-      l
-  in
-  let ty =
-    newty
-      (Tpackage
-         (s, List.map fst l, List.map (fun (_, cty) -> cty.ctyp_type) fields))
-  in
-  (s, fields, ty)
 
 let wrap_unpacks sexp unpacks =
   let open Ast_helper in
@@ -4154,12 +4140,6 @@ let type_binding env rec_flag spat_sexp_list scope =
   in
   (pat_exp_list, new_env)
 
-let type_let env rec_flag spat_sexp_list scope =
-  let pat_exp_list, new_env, _unpacks =
-    type_let env rec_flag spat_sexp_list scope false
-  in
-  (pat_exp_list, new_env)
-
 (* Typing of toplevel expressions *)
 
 let type_expression env sexp =
@@ -4436,10 +4416,6 @@ let report_error env ppf error =
        escape.@]"
   | Inlined_record_expected ->
     fprintf ppf "@[This constructor expects an inlined record argument.@]"
-  | Unrefuted_pattern pat ->
-    fprintf ppf "@[%s@ %s@ %a@]" "This match case could not be refuted."
-      "Here is an example of a value that would reach it:" Parmatch.top_pretty
-      pat
   | Invalid_extension_constructor_payload ->
     fprintf ppf
       "Invalid [%%extension_constructor] payload, a constructor is expected."
@@ -4477,8 +4453,6 @@ let report_error env ppf error =
     fprintf ppf
       "Direct field access on a dict is not supported. Use Dict.get instead."
 
-let super_report_error_no_wrap_printing_env = report_error
-
 let report_error env ppf err =
   Printtyp.wrap_printing_env env (fun () -> report_error env ppf err)
 
@@ -4489,7 +4463,4 @@ let () =
     | Error_forward err -> Some err
     | _ -> None)
 
-(* drop ?recarg argument from the external API *)
-let type_expect ?in_function env e ty = type_expect ?in_function env e ty
 let type_exp env e = type_exp env e
-let type_argument env e t1 t2 = type_argument env e t1 t2
diff --git a/compiler/ml/typecore.mli b/compiler/ml/typecore.mli
index 1a8bbed4c7..3aa23756d4 100644
--- a/compiler/ml/typecore.mli
+++ b/compiler/ml/typecore.mli
@@ -27,12 +27,6 @@ val type_binding :
   Parsetree.value_binding list ->
   Annot.ident option ->
   Typedtree.value_binding list * Env.t
-val type_let :
-  Env.t ->
-  rec_flag ->
-  Parsetree.value_binding list ->
-  Annot.ident option ->
-  Typedtree.value_binding list * Env.t
 val type_expression : Env.t -> Parsetree.expression -> Typedtree.expression
 val check_partial :
   ?lev:int ->
@@ -41,20 +35,8 @@ val check_partial :
   Location.t ->
   Typedtree.case list ->
   Typedtree.partial
-val type_expect :
-  ?in_function:Location.t * type_expr ->
-  Env.t ->
-  Parsetree.expression ->
-  type_expr ->
-  Typedtree.expression
 val type_exp : Env.t -> Parsetree.expression -> Typedtree.expression
 val type_approx : Env.t -> Parsetree.expression -> type_expr
-val type_argument :
-  Env.t ->
-  Parsetree.expression ->
-  type_expr ->
-  type_expr ->
-  Typedtree.expression
 
 val option_some : Typedtree.expression -> Typedtree.expression
 val option_none : type_expr -> Location.t -> Typedtree.expression
@@ -112,7 +94,6 @@ type error =
   | Exception_pattern_below_toplevel
   | Inlined_record_escape
   | Inlined_record_expected
-  | Unrefuted_pattern of Typedtree.pattern
   | Invalid_extension_constructor_payload
   | Not_an_extension_constructor
   | Literal_overflow of string
@@ -126,9 +107,6 @@ type error =
 exception Error of Location.t * Env.t * error
 exception Error_forward of Location.error
 
-val super_report_error_no_wrap_printing_env :
-  Env.t -> formatter -> error -> unit
-
 val report_error : Env.t -> formatter -> error -> unit
 (* Deprecated.  Use Location.{error_of_exn, report_error}. *)
 
@@ -154,10 +132,4 @@ val type_package :
   Typedtree.module_expr * type_expr list)
   ref
 
-val create_package_type :
-  Location.t ->
-  Env.t ->
-  Longident.t * (Longident.t * Parsetree.core_type) list ->
-  Path.t * (Longident.t * Typedtree.core_type) list * Types.type_expr
-
 val constant : Parsetree.constant -> (Asttypes.constant, error) result
diff --git a/compiler/ml/typemod.ml b/compiler/ml/typemod.ml
index be6ac27e51..e012a636cc 100644
--- a/compiler/ml/typemod.ml
+++ b/compiler/ml/typemod.ml
@@ -1790,12 +1790,6 @@ let type_implementation_more ?check_exists sourcefile outputprefix modulename
       (Some sourcefile) initial_env None;
     raise e
 
-let type_implementation sourcefile outputprefix modulename initial_env ast =
-  let a, b, _, _ =
-    type_implementation_more sourcefile outputprefix modulename initial_env ast
-  in
-  (a, b)
-
 let save_signature modname tsg outputprefix source_file initial_env cmi =
   Cmt_format.save_cmt (outputprefix ^ ".cmti") modname
     (Cmt_format.Interface tsg) (Some source_file) initial_env (Some cmi)
@@ -1900,8 +1894,6 @@ let report_error ppf = function
   | Cannot_scrape_alias p ->
     fprintf ppf "This is an alias for module %a, which is missing" path p
 
-let super_report_error_no_wrap_printing_env = report_error
-
 let report_error env ppf err =
   Printtyp.wrap_printing_env env (fun () -> report_error ppf err)
 
diff --git a/compiler/ml/typemod.mli b/compiler/ml/typemod.mli
index 8bef382fbe..0f36cf6afd 100644
--- a/compiler/ml/typemod.mli
+++ b/compiler/ml/typemod.mli
@@ -38,14 +38,6 @@ val type_implementation_more :
   Parsetree.structure ->
   Typedtree.structure * Typedtree.module_coercion * Env.t * Types.signature
 
-val type_implementation :
-  string ->
-  string ->
-  string ->
-  Env.t ->
-  Parsetree.structure ->
-  Typedtree.structure * Typedtree.module_coercion
-
 val transl_signature : Env.t -> Parsetree.signature -> Typedtree.signature
 val check_nongen_schemes : Env.t -> Types.signature -> unit
 val type_open_ :
@@ -96,6 +88,4 @@ type error =
 exception Error of Location.t * Env.t * error
 exception Error_forward of Location.error
 
-val super_report_error_no_wrap_printing_env : formatter -> error -> unit
-
 val report_error : Env.t -> formatter -> error -> unit
diff --git a/compiler/ml/typeopt.ml b/compiler/ml/typeopt.ml
index 350269558a..c661b5b635 100644
--- a/compiler/ml/typeopt.ml
+++ b/compiler/ml/typeopt.ml
@@ -108,8 +108,6 @@ let is_base_type env ty base_ty_path =
 let maybe_pointer_type env ty =
   if Ctype.maybe_pointer_type env ty then Pointer else Immediate
 
-let maybe_pointer exp = maybe_pointer_type exp.exp_env exp.exp_type
-
 type classification =
   | Int
   | Float
diff --git a/compiler/ml/typeopt.mli b/compiler/ml/typeopt.mli
index eb4a795a6d..38b667c273 100644
--- a/compiler/ml/typeopt.mli
+++ b/compiler/ml/typeopt.mli
@@ -20,7 +20,6 @@ val is_function_type :
 val is_base_type : Env.t -> Types.type_expr -> Path.t -> bool
 
 val maybe_pointer_type : Env.t -> Types.type_expr -> Lambda.immediate_or_pointer
-val maybe_pointer : Typedtree.expression -> Lambda.immediate_or_pointer
 
 val classify_lazy_argument :
   Typedtree.expression ->
diff --git a/compiler/ml/types.ml b/compiler/ml/types.ml
index d931fc1ec9..1886f2a727 100644
--- a/compiler/ml/types.ml
+++ b/compiler/ml/types.ml
@@ -198,11 +198,6 @@ type extension_constructor = {
   ext_is_exception: bool;
 }
 
-and type_transparence =
-  | Type_public (* unrestricted expansion *)
-  | Type_new (* "new" type *)
-  | Type_private (* private type *)
-
 (* Type expressions for the class language *)
 
 module Concr = Set.Make (OrderedString)
@@ -262,7 +257,6 @@ type constructor_description = {
   cstr_tag: constructor_tag; (* Tag for heap blocks *)
   cstr_consts: int; (* Number of constant constructors *)
   cstr_nonconsts: int; (* Number of non-const constructors *)
-  cstr_normal: int; (* Number of non generalized constrs *)
   cstr_generalized: bool; (* Constrained return type? *)
   cstr_private: private_flag; (* Read-only constructor? *)
   cstr_loc: Location.t;
diff --git a/compiler/ml/types.mli b/compiler/ml/types.mli
index 09f82c8d9e..71c19f629a 100644
--- a/compiler/ml/types.mli
+++ b/compiler/ml/types.mli
@@ -330,13 +330,6 @@ type extension_constructor = {
   ext_is_exception: bool;
 }
 
-and type_transparence =
-  | Type_public (* unrestricted expansion *)
-  | Type_new (* "new" type *)
-  | Type_private (* private type *)
-
-(* Type expressions for the class language *)
-
 module Concr : Set.S with type elt = string
 
 (* Type expressions for the module language *)
@@ -394,7 +387,6 @@ type constructor_description = {
   cstr_tag: constructor_tag; (* Tag for heap blocks *)
   cstr_consts: int; (* Number of constant constructors *)
   cstr_nonconsts: int; (* Number of non-const constructors *)
-  cstr_normal: int; (* Number of non generalized constrs *)
   cstr_generalized: bool; (* Constrained return type? *)
   cstr_private: private_flag; (* Read-only constructor? *)
   cstr_loc: Location.t;
diff --git a/compiler/ml/typetexp.ml b/compiler/ml/typetexp.ml
index 6e862aa1e6..d212eb2dc6 100644
--- a/compiler/ml/typetexp.ml
+++ b/compiler/ml/typetexp.ml
@@ -30,9 +30,6 @@ type error =
   | Unbound_type_constructor of Longident.t
   | Unbound_type_constructor_2 of Path.t
   | Type_arity_mismatch of Longident.t * int * int
-  | Bound_type_variable of string
-  | Recursive_type
-  | Unbound_row_variable of Longident.t
   | Type_mismatch of (type_expr * type_expr) list
   | Alias_type_mismatch of (type_expr * type_expr) list
   | Present_has_conjunction of string
@@ -131,7 +128,6 @@ let find_constructor =
 let find_all_constructors =
   find_component Env.lookup_all_constructors (fun lid ->
       Unbound_constructor lid)
-let find_label = find_component Env.lookup_label (fun lid -> Unbound_label lid)
 let find_all_labels =
   find_component Env.lookup_all_labels (fun lid -> Unbound_label lid)
 
@@ -232,11 +228,6 @@ let validate_name = function
 let new_global_var ?name () = new_global_var ?name:(validate_name name) ()
 let newvar ?name () = newvar ?name:(validate_name name) ()
 
-let type_variable loc name =
-  try Tbl.find name !type_variables
-  with Not_found ->
-    raise (Error (loc, Env.empty, Unbound_type_variable ("'" ^ name)))
-
 let transl_type_param env styp =
   let loc = styp.ptyp_loc in
   match styp.ptyp_desc with
@@ -668,8 +659,6 @@ let make_fixed_univars ty =
   make_fixed_univars ty;
   Btype.unmark_type ty
 
-let create_package_mty = create_package_mty false
-
 let globalize_used_variables env fixed =
   let r = ref [] in
   Tbl.iter
@@ -709,40 +698,6 @@ let transl_simple_type env fixed styp =
   make_fixed_univars typ.ctyp_type;
   typ
 
-let transl_simple_type_univars env styp =
-  univars := [];
-  used_variables := Tbl.empty;
-  pre_univars := [];
-  begin_def ();
-  let typ = transl_type env Univars styp in
-  (* Only keep already global variables in used_variables *)
-  let new_variables = !used_variables in
-  used_variables := Tbl.empty;
-  Tbl.iter
-    (fun name p ->
-      if Tbl.mem name !type_variables then
-        used_variables := Tbl.add name p !used_variables)
-    new_variables;
-  globalize_used_variables env false ();
-  end_def ();
-  generalize typ.ctyp_type;
-  let univs =
-    List.fold_left
-      (fun acc v ->
-        let v = repr v in
-        match v.desc with
-        | Tvar name when v.level = Btype.generic_level ->
-          v.desc <- Tunivar name;
-          v :: acc
-        | _ -> acc)
-      [] !pre_univars
-  in
-  make_fixed_univars typ.ctyp_type;
-  {
-    typ with
-    ctyp_type = instance env (Btype.newgenty (Tpoly (typ.ctyp_type, univs)));
-  }
-
 let transl_simple_type_delayed env styp =
   univars := [];
   used_variables := Tbl.empty;
@@ -836,13 +791,6 @@ let report_error env ppf = function
         "@[The type constructor %a@ expects %i argument(s),@ but is here \
          applied to %i argument(s)@]"
         longident lid expected provided
-  | Bound_type_variable name ->
-    fprintf ppf "Already bound type parameter '%s" name
-  | Recursive_type -> fprintf ppf "This type is recursive"
-  | Unbound_row_variable lid ->
-    (* we don't use "spellcheck" here: this error is not raised
-       anywhere so it's unclear how it should be handled *)
-    fprintf ppf "Unbound row variable in #%a" longident lid
   | Type_mismatch trace ->
     Printtyp.report_unification_error ppf Env.empty trace
       (function
diff --git a/compiler/ml/typetexp.mli b/compiler/ml/typetexp.mli
index be9a9302cd..f09c26c58e 100644
--- a/compiler/ml/typetexp.mli
+++ b/compiler/ml/typetexp.mli
@@ -19,8 +19,6 @@ open Types
 
 val transl_simple_type :
   Env.t -> bool -> Parsetree.core_type -> Typedtree.core_type
-val transl_simple_type_univars :
-  Env.t -> Parsetree.core_type -> Typedtree.core_type
 val transl_simple_type_delayed :
   Env.t -> Parsetree.core_type -> Typedtree.core_type * (unit -> unit)
 (* Translate a type, but leave type variables unbound. Returns
@@ -28,7 +26,6 @@ val transl_simple_type_delayed :
 
 val transl_type_scheme : Env.t -> Parsetree.core_type -> Typedtree.core_type
 val reset_type_variables : unit -> unit
-val type_variable : Location.t -> string -> type_expr
 val transl_type_param : Env.t -> Parsetree.core_type -> Typedtree.core_type
 
 type variable_context
@@ -42,9 +39,6 @@ type error =
   | Unbound_type_constructor of Longident.t
   | Unbound_type_constructor_2 of Path.t
   | Type_arity_mismatch of Longident.t * int * int
-  | Bound_type_variable of string
-  | Recursive_type
-  | Unbound_row_variable of Longident.t
   | Type_mismatch of (type_expr * type_expr) list
   | Alias_type_mismatch of (type_expr * type_expr) list
   | Present_has_conjunction of string
@@ -80,11 +74,6 @@ val transl_modtype_longident :
 val transl_modtype :
   (* from Typemod *)
   (Env.t -> Parsetree.module_type -> Typedtree.module_type) ref
-val create_package_mty :
-  Location.t ->
-  Env.t ->
-  Parsetree.package_type ->
-  (Longident.t Asttypes.loc * Parsetree.core_type) list * Parsetree.module_type
 
 val find_type : Env.t -> Location.t -> Longident.t -> Path.t * type_declaration
 val find_constructor :
@@ -94,7 +83,6 @@ val find_all_constructors :
   Location.t ->
   Longident.t ->
   (constructor_description * (unit -> unit)) list
-val find_label : Env.t -> Location.t -> Longident.t -> label_description
 val find_all_labels :
   Env.t ->
   Location.t ->
@@ -110,14 +98,3 @@ val find_modtype :
 
 val unbound_constructor_error : Env.t -> Longident.t Location.loc -> 'a
 val unbound_label_error : Env.t -> Longident.t Location.loc -> 'a
-
-val spellcheck :
-  Format.formatter ->
-  (('a -> 'a list -> 'a list) ->
-  Longident.t option ->
-  'b ->
-  'c list ->
-  string list) ->
-  'b ->
-  Longident.t ->
-  unit
diff --git a/compiler/ml/unified_ops.ml b/compiler/ml/unified_ops.ml
index c57c14bce0..980f7bd1f3 100644
--- a/compiler/ml/unified_ops.ml
+++ b/compiler/ml/unified_ops.ml
@@ -128,7 +128,7 @@ let entries =
       form = Binary;
       specialization =
         {
-          int = Pdivint Safe;
+          int = Pdivint;
           bool = None;
           float = Some Pdivfloat;
           bigint = Some Pdivbigint;
@@ -141,7 +141,7 @@ let entries =
       form = Binary;
       specialization =
         {
-          int = Pmodint Safe;
+          int = Pmodint;
           bool = None;
           float = Some Pmodfloat;
           bigint = Some Pmodbigint;
@@ -154,7 +154,7 @@ let entries =
       form = Binary;
       specialization =
         {
-          int = Pmodint Safe;
+          int = Pmodint;
           bool = None;
           float = Some Pmodfloat;
           bigint = Some Pmodbigint;
diff --git a/compiler/ml/variant_coercion.ml b/compiler/ml/variant_coercion.ml
index 06f5f627a7..ecec066c63 100644
--- a/compiler/ml/variant_coercion.ml
+++ b/compiler/ml/variant_coercion.ml
@@ -21,10 +21,6 @@ let variant_has_catch_all_case
 
   constructors |> List.exists has_catch_all_string_case
 
-let variant_has_relevant_primitive_catch_all
-    (constructors : Types.constructor_declaration list) =
-  variant_has_catch_all_case constructors can_coerce_primitive
-
 (* Checks if every case of the variant has the same runtime representation as the target type. *)
 let variant_has_same_runtime_representation_as_target ~(target_path : Path.t)
     ~unboxed (constructors : Types.constructor_declaration list) =