diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2ed32b8684..ae187fc1ff 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -24,6 +24,7 @@
 - AST cleanup: Prepare for ast async cleanup: Refactor code for "@res.async" payload handling and clean up handling of type and term parameters, so that now each `=>` in a function definition corresponds to a function. https://github.com/rescript-lang/rescript/pull/7223
 - AST: always put type parameters first in function definitions. https://github.com/rescript-lang/rescript/pull/7233
 - AST cleanup: Remove `@res.async` attribute from the internal representation, and add a flag to untyped and typed ASTs instead. https://github.com/rescript-lang/rescript/pull/7234
+- AST cleanup: Remove `expression_desc.Pexp_new`, `expression_desc.Pexp_setinstvar`, `expression_desc.Pexp_override`, `expression_desc.Pexp_poly`, `exp_extra.Texp_poly`, `expression_desc.Texp_new`, `expression_desc.Texp_setinstvar`, `expression_desc.Texp_override` & `expression_desc.Texp_instvar` from AST as it is unused. https://github.com/rescript-lang/rescript/pull/7239
 - AST cleanup: Remove `@res.partial` attribute from the internal representation, and add a flag to untyped and typed ASTs instead. https://github.com/rescript-lang/rescript/pull/7238 https://github.com/rescript-lang/rescript/pull/7240
 
 # 12.0.0-alpha.7
diff --git a/analysis/reanalyze/src/Arnold.ml b/analysis/reanalyze/src/Arnold.ml
index 444c4d592e..70d1f97924 100644
--- a/analysis/reanalyze/src/Arnold.ml
+++ b/analysis/reanalyze/src/Arnold.ml
@@ -982,18 +982,6 @@ module Compile = struct
     | Texp_send _ ->
       notImplemented "Texp_send";
       assert false
-    | Texp_new _ ->
-      notImplemented "Texp_new";
-      assert false
-    | Texp_instvar _ ->
-      notImplemented "Texp_instvar";
-      assert false
-    | Texp_setinstvar _ ->
-      notImplemented "Texp_setinstvar";
-      assert false
-    | Texp_override _ ->
-      notImplemented "Texp_override";
-      assert false
     | Texp_letmodule _ ->
       notImplemented "Texp_letmodule";
       assert false
diff --git a/analysis/reanalyze/src/SideEffects.ml b/analysis/reanalyze/src/SideEffects.ml
index b668d1f9bc..5d4c077241 100644
--- a/analysis/reanalyze/src/SideEffects.ml
+++ b/analysis/reanalyze/src/SideEffects.ml
@@ -61,10 +61,6 @@ let rec exprNoSideEffects (expr : Typedtree.expression) =
     e1 |> exprNoSideEffects && e2 |> exprNoSideEffects
     && e3 |> exprNoSideEffects
   | Texp_send _ -> false
-  | Texp_new _ -> true
-  | Texp_instvar _ -> true
-  | Texp_setinstvar _ -> false
-  | Texp_override _ -> false
   | Texp_letexception (_ec, e) -> e |> exprNoSideEffects
   | Texp_pack _ -> false
   | Texp_extension_constructor _ when true -> true
diff --git a/analysis/src/Utils.ml b/analysis/src/Utils.ml
index 127ceef0f3..c274b5a9fb 100644
--- a/analysis/src/Utils.ml
+++ b/analysis/src/Utils.ml
@@ -103,14 +103,10 @@ let identifyPexp pexp =
   | Pexp_constraint _ -> "Pexp_constraint"
   | Pexp_coerce _ -> "Pexp_coerce"
   | Pexp_send _ -> "Pexp_send"
-  | Pexp_new _ -> "Pexp_new"
-  | Pexp_setinstvar _ -> "Pexp_setinstvar"
-  | Pexp_override _ -> "Pexp_override"
   | Pexp_letmodule _ -> "Pexp_letmodule"
   | Pexp_letexception _ -> "Pexp_letexception"
   | Pexp_assert _ -> "Pexp_assert"
   | Pexp_lazy _ -> "Pexp_lazy"
-  | Pexp_poly _ -> "Pexp_poly"
   | Pexp_newtype _ -> "Pexp_newtype"
   | Pexp_pack _ -> "Pexp_pack"
   | Pexp_extension _ -> "Pexp_extension"
diff --git a/compiler/frontend/bs_ast_invariant.ml b/compiler/frontend/bs_ast_invariant.ml
index 6870c6d160..7da08fea57 100644
--- a/compiler/frontend/bs_ast_invariant.ml
+++ b/compiler/frontend/bs_ast_invariant.ml
@@ -94,8 +94,6 @@ let emit_external_warnings : iterator =
       (fun self ({pexp_loc = loc} as a) ->
         match a.pexp_desc with
         | Pexp_constant const -> check_constant loc const
-        | Pexp_new _ ->
-          Location.raise_errorf ~loc "OCaml style objects are not supported"
         | Pexp_variant (s, None) when Ext_string.is_valid_hash_number s -> (
           try ignore (Ext_string.hash_number_as_i32_exn s : int32)
           with _ ->
diff --git a/compiler/frontend/bs_ast_mapper.ml b/compiler/frontend/bs_ast_mapper.ml
index 992edc60c6..292fe15b9c 100644
--- a/compiler/frontend/bs_ast_mapper.ml
+++ b/compiler/frontend/bs_ast_mapper.ml
@@ -355,12 +355,6 @@ module E = struct
     | Pexp_constraint (e, t) ->
       constraint_ ~loc ~attrs (sub.expr sub e) (sub.typ sub t)
     | Pexp_send (e, s) -> send ~loc ~attrs (sub.expr sub e) (map_loc sub s)
-    | Pexp_new lid -> new_ ~loc ~attrs (map_loc sub lid)
-    | Pexp_setinstvar (s, e) ->
-      setinstvar ~loc ~attrs (map_loc sub s) (sub.expr sub e)
-    | Pexp_override sel ->
-      override ~loc ~attrs
-        (List.map (map_tuple (map_loc sub) (sub.expr sub)) sel)
     | Pexp_letmodule (s, me, e) ->
       letmodule ~loc ~attrs (map_loc sub s) (sub.module_expr sub me)
         (sub.expr sub e)
@@ -370,8 +364,6 @@ module E = struct
         (sub.expr sub e)
     | Pexp_assert e -> assert_ ~loc ~attrs (sub.expr sub e)
     | Pexp_lazy e -> lazy_ ~loc ~attrs (sub.expr sub e)
-    | Pexp_poly (e, t) ->
-      poly ~loc ~attrs (sub.expr sub e) (map_opt (sub.typ sub) t)
     | Pexp_newtype (s, e) ->
       newtype ~loc ~attrs (map_loc sub s) (sub.expr sub e)
     | Pexp_pack me -> pack ~loc ~attrs (sub.module_expr sub me)
diff --git a/compiler/frontend/bs_builtin_ppx.ml b/compiler/frontend/bs_builtin_ppx.ml
index 054a9976a3..b15a683ddd 100644
--- a/compiler/frontend/bs_builtin_ppx.ml
+++ b/compiler/frontend/bs_builtin_ppx.ml
@@ -87,24 +87,6 @@ let expr_mapper ~async_context ~in_function_def (self : mapper)
   (* Its output should not be rewritten anymore *)
   | Pexp_extension extension ->
     Ast_exp_extension.handle_extension e self extension
-  | Pexp_setinstvar ({txt; loc}, expr) ->
-    if Stack.is_empty Js_config.self_stack then
-      Location.raise_errorf ~loc:e.pexp_loc
-        "This assignment can only happen in object context";
-    let name = Stack.top Js_config.self_stack in
-    if name = "" then
-      Location.raise_errorf ~loc:e.pexp_loc
-        "The current object does not assign a name";
-    let open Ast_helper in
-    self.expr self
-      (Exp.apply ~loc:e.pexp_loc
-         (Exp.ident ~loc {loc; txt = Lident "#="})
-         [
-           ( Nolabel,
-             Exp.send ~loc (Exp.ident ~loc {loc; txt = Lident name}) {loc; txt}
-           );
-           (Nolabel, expr);
-         ])
   | Pexp_constant (Pconst_string (s, Some delim)) ->
     Ast_utf8_string_interp.transform_exp e s delim
   | Pexp_constant (Pconst_integer (s, Some 'l')) ->
diff --git a/compiler/ml/ast_helper.ml b/compiler/ml/ast_helper.ml
index 096ba9264a..4b5d055815 100644
--- a/compiler/ml/ast_helper.ml
+++ b/compiler/ml/ast_helper.ml
@@ -172,14 +172,10 @@ module Exp = struct
   let constraint_ ?loc ?attrs a b = mk ?loc ?attrs (Pexp_constraint (a, b))
   let coerce ?loc ?attrs a c = mk ?loc ?attrs (Pexp_coerce (a, (), c))
   let send ?loc ?attrs a b = mk ?loc ?attrs (Pexp_send (a, b))
-  let new_ ?loc ?attrs a = mk ?loc ?attrs (Pexp_new a)
-  let setinstvar ?loc ?attrs a b = mk ?loc ?attrs (Pexp_setinstvar (a, b))
-  let override ?loc ?attrs a = mk ?loc ?attrs (Pexp_override a)
   let letmodule ?loc ?attrs a b c = mk ?loc ?attrs (Pexp_letmodule (a, b, c))
   let letexception ?loc ?attrs a b = mk ?loc ?attrs (Pexp_letexception (a, b))
   let assert_ ?loc ?attrs a = mk ?loc ?attrs (Pexp_assert a)
   let lazy_ ?loc ?attrs a = mk ?loc ?attrs (Pexp_lazy a)
-  let poly ?loc ?attrs a b = mk ?loc ?attrs (Pexp_poly (a, b))
   let newtype ?loc ?attrs a b = mk ?loc ?attrs (Pexp_newtype (a, b))
   let pack ?loc ?attrs a = mk ?loc ?attrs (Pexp_pack a)
   let open_ ?loc ?attrs a b c = mk ?loc ?attrs (Pexp_open (a, b, c))
diff --git a/compiler/ml/ast_helper.mli b/compiler/ml/ast_helper.mli
index 5133c6e2f1..a78e33589e 100644
--- a/compiler/ml/ast_helper.mli
+++ b/compiler/ml/ast_helper.mli
@@ -193,10 +193,6 @@ module Exp : sig
   val constraint_ :
     ?loc:loc -> ?attrs:attrs -> expression -> core_type -> expression
   val send : ?loc:loc -> ?attrs:attrs -> expression -> str -> expression
-  val new_ : ?loc:loc -> ?attrs:attrs -> lid -> expression
-  val setinstvar : ?loc:loc -> ?attrs:attrs -> str -> expression -> expression
-  val override :
-    ?loc:loc -> ?attrs:attrs -> (str * expression) list -> expression
   val letmodule :
     ?loc:loc -> ?attrs:attrs -> str -> module_expr -> expression -> expression
   val letexception :
@@ -207,8 +203,6 @@ module Exp : sig
     expression
   val assert_ : ?loc:loc -> ?attrs:attrs -> expression -> expression
   val lazy_ : ?loc:loc -> ?attrs:attrs -> expression -> expression
-  val poly :
-    ?loc:loc -> ?attrs:attrs -> expression -> core_type option -> expression
   val newtype : ?loc:loc -> ?attrs:attrs -> str -> expression -> expression
   val pack : ?loc:loc -> ?attrs:attrs -> module_expr -> expression
   val open_ :
diff --git a/compiler/ml/ast_iterator.ml b/compiler/ml/ast_iterator.ml
index 667953f976..2c76f6e5b4 100644
--- a/compiler/ml/ast_iterator.ml
+++ b/compiler/ml/ast_iterator.ml
@@ -333,12 +333,6 @@ module E = struct
       sub.expr sub e;
       sub.typ sub t
     | Pexp_send (e, _s) -> sub.expr sub e
-    | Pexp_new lid -> iter_loc sub lid
-    | Pexp_setinstvar (s, e) ->
-      iter_loc sub s;
-      sub.expr sub e
-    | Pexp_override sel ->
-      List.iter (iter_tuple (iter_loc sub) (sub.expr sub)) sel
     | Pexp_letmodule (s, me, e) ->
       iter_loc sub s;
       sub.module_expr sub me;
@@ -348,9 +342,6 @@ module E = struct
       sub.expr sub e
     | Pexp_assert e -> sub.expr sub e
     | Pexp_lazy e -> sub.expr sub e
-    | Pexp_poly (e, t) ->
-      sub.expr sub e;
-      iter_opt (sub.typ sub) t
     | Pexp_newtype (_s, e) -> sub.expr sub e
     | Pexp_pack me -> sub.module_expr sub me
     | Pexp_open (_ovf, lid, e) ->
diff --git a/compiler/ml/ast_mapper.ml b/compiler/ml/ast_mapper.ml
index a19152e37c..854e003c99 100644
--- a/compiler/ml/ast_mapper.ml
+++ b/compiler/ml/ast_mapper.ml
@@ -318,12 +318,6 @@ module E = struct
     | Pexp_constraint (e, t) ->
       constraint_ ~loc ~attrs (sub.expr sub e) (sub.typ sub t)
     | Pexp_send (e, s) -> send ~loc ~attrs (sub.expr sub e) (map_loc sub s)
-    | Pexp_new lid -> new_ ~loc ~attrs (map_loc sub lid)
-    | Pexp_setinstvar (s, e) ->
-      setinstvar ~loc ~attrs (map_loc sub s) (sub.expr sub e)
-    | Pexp_override sel ->
-      override ~loc ~attrs
-        (List.map (map_tuple (map_loc sub) (sub.expr sub)) sel)
     | Pexp_letmodule (s, me, e) ->
       letmodule ~loc ~attrs (map_loc sub s) (sub.module_expr sub me)
         (sub.expr sub e)
@@ -333,8 +327,6 @@ module E = struct
         (sub.expr sub e)
     | Pexp_assert e -> assert_ ~loc ~attrs (sub.expr sub e)
     | Pexp_lazy e -> lazy_ ~loc ~attrs (sub.expr sub e)
-    | Pexp_poly (e, t) ->
-      poly ~loc ~attrs (sub.expr sub e) (map_opt (sub.typ sub) t)
     | Pexp_newtype (s, e) ->
       newtype ~loc ~attrs (map_loc sub s) (sub.expr sub e)
     | Pexp_pack me -> pack ~loc ~attrs (sub.module_expr sub me)
diff --git a/compiler/ml/ast_mapper_from0.ml b/compiler/ml/ast_mapper_from0.ml
index 88b67b5a20..22d59a792f 100644
--- a/compiler/ml/ast_mapper_from0.ml
+++ b/compiler/ml/ast_mapper_from0.ml
@@ -387,12 +387,11 @@ module E = struct
     | Pexp_constraint (e, t) ->
       constraint_ ~loc ~attrs (sub.expr sub e) (sub.typ sub t)
     | Pexp_send (e, s) -> send ~loc ~attrs (sub.expr sub e) (map_loc sub s)
-    | Pexp_new lid -> new_ ~loc ~attrs (map_loc sub lid)
-    | Pexp_setinstvar (s, e) ->
-      setinstvar ~loc ~attrs (map_loc sub s) (sub.expr sub e)
-    | Pexp_override sel ->
-      override ~loc ~attrs
-        (List.map (map_tuple (map_loc sub) (sub.expr sub)) sel)
+    | Pexp_new _ -> failwith "Pexp_new is no longer present in ReScript"
+    | Pexp_setinstvar _ ->
+      failwith "Pexp_setinstvar is no longer present in ReScript"
+    | Pexp_override _ ->
+      failwith "Pexp_override is no longer present in ReScript"
     | Pexp_letmodule (s, me, e) ->
       letmodule ~loc ~attrs (map_loc sub s) (sub.module_expr sub me)
         (sub.expr sub e)
@@ -402,8 +401,7 @@ module E = struct
         (sub.expr sub e)
     | Pexp_assert e -> assert_ ~loc ~attrs (sub.expr sub e)
     | Pexp_lazy e -> lazy_ ~loc ~attrs (sub.expr sub e)
-    | Pexp_poly (e, t) ->
-      poly ~loc ~attrs (sub.expr sub e) (map_opt (sub.typ sub) t)
+    | Pexp_poly _ -> failwith "Pexp_poly is no longer present in ReScript"
     | Pexp_object () -> assert false
     | Pexp_newtype (s, e) ->
       newtype ~loc ~attrs (map_loc sub s) (sub.expr sub e)
diff --git a/compiler/ml/ast_mapper_to0.ml b/compiler/ml/ast_mapper_to0.ml
index 2a159a07d6..68be8b7cbf 100644
--- a/compiler/ml/ast_mapper_to0.ml
+++ b/compiler/ml/ast_mapper_to0.ml
@@ -369,12 +369,6 @@ module E = struct
     | Pexp_constraint (e, t) ->
       constraint_ ~loc ~attrs (sub.expr sub e) (sub.typ sub t)
     | Pexp_send (e, s) -> send ~loc ~attrs (sub.expr sub e) (map_loc sub s)
-    | Pexp_new lid -> new_ ~loc ~attrs (map_loc sub lid)
-    | Pexp_setinstvar (s, e) ->
-      setinstvar ~loc ~attrs (map_loc sub s) (sub.expr sub e)
-    | Pexp_override sel ->
-      override ~loc ~attrs
-        (List.map (map_tuple (map_loc sub) (sub.expr sub)) sel)
     | Pexp_letmodule (s, me, e) ->
       letmodule ~loc ~attrs (map_loc sub s) (sub.module_expr sub me)
         (sub.expr sub e)
@@ -384,8 +378,6 @@ module E = struct
         (sub.expr sub e)
     | Pexp_assert e -> assert_ ~loc ~attrs (sub.expr sub e)
     | Pexp_lazy e -> lazy_ ~loc ~attrs (sub.expr sub e)
-    | Pexp_poly (e, t) ->
-      poly ~loc ~attrs (sub.expr sub e) (map_opt (sub.typ sub) t)
     | Pexp_newtype (s, e) ->
       newtype ~loc ~attrs (map_loc sub s) (sub.expr sub e)
     | Pexp_pack me -> pack ~loc ~attrs (sub.module_expr sub me)
diff --git a/compiler/ml/depend.ml b/compiler/ml/depend.ml
index 7688750242..47d54954f6 100644
--- a/compiler/ml/depend.ml
+++ b/compiler/ml/depend.ml
@@ -271,18 +271,12 @@ let rec add_expr bv exp =
     add_expr bv e1;
     add_type bv ty2
   | Pexp_send (e, _m) -> add_expr bv e
-  | Pexp_new li -> add bv li
-  | Pexp_setinstvar (_v, e) -> add_expr bv e
-  | Pexp_override sel -> List.iter (fun (_s, e) -> add_expr bv e) sel
   | Pexp_letmodule (id, m, e) ->
     let b = add_module_binding bv m in
     add_expr (StringMap.add id.txt b bv) e
   | Pexp_letexception (_, e) -> add_expr bv e
   | Pexp_assert e -> add_expr bv e
   | Pexp_lazy e -> add_expr bv e
-  | Pexp_poly (e, t) ->
-    add_expr bv e;
-    add_opt add_type bv t
   | Pexp_newtype (_, e) -> add_expr bv e
   | Pexp_pack m -> add_module bv m
   | Pexp_open (_ovf, m, e) ->
diff --git a/compiler/ml/parsetree.ml b/compiler/ml/parsetree.ml
index 26c6ca9da7..a56f4c9439 100644
--- a/compiler/ml/parsetree.ml
+++ b/compiler/ml/parsetree.ml
@@ -295,10 +295,6 @@ and expression_desc =
     (* (E :> T)        (None, T)
          *)
   | Pexp_send of expression * label loc (*  E # m *)
-  | Pexp_new of Longident.t loc (* new M.c *)
-  | Pexp_setinstvar of label loc * expression (* x <- 2 *)
-  | Pexp_override of (label loc * expression) list
-    (* {< x1 = E1; ...; Xn = En >} *)
   | Pexp_letmodule of string loc * module_expr * expression
     (* let module M = ME in E *)
   | Pexp_letexception of extension_constructor * expression
@@ -308,11 +304,6 @@ and expression_desc =
        Note: "assert false" is treated in a special way by the
        type-checker. *)
   | Pexp_lazy of expression (* lazy E *)
-  | Pexp_poly of expression * core_type option
-    (* Used for method bodies.
-
-       Can only be used as the expression under Cfk_concrete
-       for methods (not values). *)
   | Pexp_newtype of string loc * expression (* fun (type t) -> E *)
   | Pexp_pack of module_expr
     (* (module ME)
diff --git a/compiler/ml/pprintast.ml b/compiler/ml/pprintast.ml
index 7b089e33ec..2517d60e7d 100644
--- a/compiler/ml/pprintast.ml
+++ b/compiler/ml/pprintast.ml
@@ -706,15 +706,6 @@ and expression ctxt f x =
       in
       let lst = sequence_helper [] x in
       pp f "@[<hv>%a@]" (list (expression (under_semi ctxt)) ~sep:";@;") lst
-    | Pexp_new li -> pp f "@[<hov2>new@ %a@]" longident_loc li
-    | Pexp_setinstvar (s, e) ->
-      pp f "@[<hov2>%s@ <-@ %a@]" s.txt (expression ctxt) e
-    | Pexp_override l ->
-      (* FIXME *)
-      let string_x_expression f (s, e) =
-        pp f "@[<hov2>%s@ =@ %a@]" s.txt (expression ctxt) e
-      in
-      pp f "@[<hov2>{<%a>}@]" (list string_x_expression ~sep:";") l
     | Pexp_letmodule (s, me, e) ->
       pp f "@[<hov2>let@ module@ %s@ =@ %a@ in@ %a@]" s.txt
         (module_expr reset_ctxt) me (expression ctxt) e
@@ -724,12 +715,6 @@ and expression ctxt f x =
         cd (expression ctxt) e
     | Pexp_assert e -> pp f "@[<hov2>assert@ %a@]" (simple_expr ctxt) e
     | Pexp_lazy e -> pp f "@[<hov2>lazy@ %a@]" (simple_expr ctxt) e
-    (* Pexp_poly: impossible but we should print it anyway, rather than
-       assert false *)
-    | Pexp_poly (e, None) -> pp f "@[<hov2>!poly!@ %a@]" (simple_expr ctxt) e
-    | Pexp_poly (e, Some ct) ->
-      pp f "@[<hov2>(!poly!@ %a@ : %a)@]" (simple_expr ctxt) e (core_type ctxt)
-        ct
     | Pexp_open (ovf, lid, e) ->
       pp f "@[<2>let open%s %a in@;%a@]" (override ovf) longident_loc lid
         (expression ctxt) e
diff --git a/compiler/ml/printast.ml b/compiler/ml/printast.ml
index 338db444a5..9af6ff95fc 100644
--- a/compiler/ml/printast.ml
+++ b/compiler/ml/printast.ml
@@ -318,13 +318,6 @@ and expression i ppf x =
   | Pexp_send (e, s) ->
     line i ppf "Pexp_send \"%s\"\n" s.txt;
     expression i ppf e
-  | Pexp_new li -> line i ppf "Pexp_new %a\n" fmt_longident_loc li
-  | Pexp_setinstvar (s, e) ->
-    line i ppf "Pexp_setinstvar %a\n" fmt_string_loc s;
-    expression i ppf e
-  | Pexp_override l ->
-    line i ppf "Pexp_override\n";
-    list i string_x_expression ppf l
   | Pexp_letmodule (s, me, e) ->
     line i ppf "Pexp_letmodule %a\n" fmt_string_loc s;
     module_expr i ppf me;
@@ -339,10 +332,6 @@ and expression i ppf x =
   | Pexp_lazy e ->
     line i ppf "Pexp_lazy\n";
     expression i ppf e
-  | Pexp_poly (e, cto) ->
-    line i ppf "Pexp_poly\n";
-    expression i ppf e;
-    option i core_type ppf cto
   | Pexp_newtype (s, e) ->
     line i ppf "Pexp_newtype \"%s\"\n" s.txt;
     expression i ppf e
@@ -666,10 +655,6 @@ and value_binding i ppf x =
   pattern (i + 1) ppf x.pvb_pat;
   expression (i + 1) ppf x.pvb_expr
 
-and string_x_expression i ppf (s, e) =
-  line i ppf "<override> %a\n" fmt_string_loc s;
-  expression (i + 1) ppf e
-
 and longident_x_expression i ppf (li, e, opt) =
   line i ppf "%a%s\n" fmt_longident_loc li (if opt then "?" else "");
   expression (i + 1) ppf e
diff --git a/compiler/ml/printtyped.ml b/compiler/ml/printtyped.ml
index 9196c2534d..24aea0b5f6 100644
--- a/compiler/ml/printtyped.ml
+++ b/compiler/ml/printtyped.ml
@@ -259,10 +259,6 @@ and expression_extra i ppf x attrs =
   | Texp_open (ovf, m, _, _) ->
     line i ppf "Texp_open %a \"%a\"\n" fmt_override_flag ovf fmt_path m;
     attributes i ppf attrs
-  | Texp_poly cto ->
-    line i ppf "Texp_poly\n";
-    attributes i ppf attrs;
-    option i core_type ppf cto
   | Texp_newtype s ->
     line i ppf "Texp_newtype \"%s\"\n" s;
     attributes i ppf attrs
@@ -279,7 +275,6 @@ and expression i ppf x =
   in
   match x.exp_desc with
   | Texp_ident (li, _, _) -> line i ppf "Texp_ident %a\n" fmt_path li
-  | Texp_instvar () -> assert false
   | Texp_constant c -> line i ppf "Texp_constant %a\n" fmt_constant c
   | Texp_let (rf, l, e) ->
     line i ppf "Texp_let %a\n" fmt_rec_flag rf;
@@ -361,7 +356,6 @@ and expression i ppf x =
     line i ppf "Texp_send \"%s\"\n" s;
     expression i ppf e;
     option i expression ppf eo
-  | Texp_new _ | Texp_setinstvar _ | Texp_override _ -> ()
   | Texp_letmodule (s, _, me, e) ->
     line i ppf "Texp_letmodule \"%a\"\n" fmt_ident s;
     module_expr i ppf me;
diff --git a/compiler/ml/rec_check.ml b/compiler/ml/rec_check.ml
index 2c6512aba2..e8b523882e 100644
--- a/compiler/ml/rec_check.ml
+++ b/compiler/ml/rec_check.ml
@@ -195,16 +195,15 @@ let rec classify_expression : Typedtree.expression -> sd =
   | Texp_sequence (_, e)
   | Texp_letexception (_, e) ->
     classify_expression e
-  | Texp_ident _ | Texp_for _ | Texp_constant _ | Texp_new _ | Texp_instvar _
-  | Texp_tuple _ | Texp_array _ | Texp_construct _ | Texp_variant _
-  | Texp_record _ | Texp_setfield _ | Texp_while _ | Texp_setinstvar _
-  | Texp_pack _ | Texp_function _ | Texp_lazy _ | Texp_extension_constructor _
-    ->
+  | Texp_ident _ | Texp_for _ | Texp_constant _ | Texp_tuple _ | Texp_array _
+  | Texp_construct _ | Texp_variant _ | Texp_record _ | Texp_setfield _
+  | Texp_while _ | Texp_pack _ | Texp_function _ | Texp_lazy _
+  | Texp_extension_constructor _ ->
     Static
   | Texp_apply {funct = {exp_desc = Texp_ident (_, _, vd)}} when is_ref vd ->
     Static
   | Texp_apply _ | Texp_match _ | Texp_ifthenelse _ | Texp_send _ | Texp_field _
-  | Texp_assert _ | Texp_try _ | Texp_override _ ->
+  | Texp_assert _ | Texp_try _ ->
     Dynamic
 
 let rec expression : Env.env -> Typedtree.expression -> Use.t =
@@ -234,8 +233,6 @@ let rec expression : Env.env -> Typedtree.expression -> Use.t =
            for inclusion in another value *)
         (discard (expression env e3)))
   | Texp_constant _ -> Use.empty
-  | Texp_new _ -> assert false
-  | Texp_instvar _ -> Use.empty
   | Texp_apply
       {funct = {exp_desc = Texp_ident (_, _, vd)}; args = [(_, Some arg)]}
     when is_ref vd ->
@@ -285,7 +282,6 @@ let rec expression : Env.env -> Typedtree.expression -> Use.t =
     Use.(
       join (inspect (expression env e1)) (inspect (option expression env eo)))
   | Texp_field (e, _, _) -> Use.(inspect (expression env e))
-  | Texp_setinstvar () -> assert false
   | Texp_letexception (_, e) -> expression env e
   | Texp_assert e -> Use.inspect (expression env e)
   | Texp_pack m -> modexp env m
@@ -293,7 +289,6 @@ let rec expression : Env.env -> Typedtree.expression -> Use.t =
     (* This is more permissive than the old check. *)
     let case env {Typedtree.c_rhs} = expression env c_rhs in
     Use.join (expression env e) (list case env cases)
-  | Texp_override () -> assert false
   | Texp_function {case = case_} ->
     Use.delay (list (case ~scrutinee:Use.empty) env [case_])
   | Texp_lazy e -> (
diff --git a/compiler/ml/tast_iterator.ml b/compiler/ml/tast_iterator.ml
index 941a8c421d..e9d0d1688f 100644
--- a/compiler/ml/tast_iterator.ml
+++ b/compiler/ml/tast_iterator.ml
@@ -144,7 +144,6 @@ let expr sub {exp_extra; exp_desc; exp_env; _} =
     | Texp_constraint cty -> sub.typ sub cty
     | Texp_coerce ((), cty2) -> sub.typ sub cty2
     | Texp_newtype _ -> ()
-    | Texp_poly cto -> Option.iter (sub.typ sub) cto
     | Texp_open (_, _, _, _) -> ()
   in
   List.iter (fun (e, _, _) -> extra e) exp_extra;
@@ -198,10 +197,6 @@ let expr sub {exp_extra; exp_desc; exp_env; _} =
   | Texp_send (exp, _, expo) ->
     sub.expr sub exp;
     Option.iter (sub.expr sub) expo
-  | Texp_new _ -> ()
-  | Texp_instvar _ -> ()
-  | Texp_setinstvar _ -> ()
-  | Texp_override _ -> ()
   | Texp_letmodule (_, _, mexpr, exp) ->
     sub.module_expr sub mexpr;
     sub.expr sub exp
diff --git a/compiler/ml/tast_mapper.ml b/compiler/ml/tast_mapper.ml
index bc367a85c1..2a351d783e 100644
--- a/compiler/ml/tast_mapper.ml
+++ b/compiler/ml/tast_mapper.ml
@@ -189,7 +189,6 @@ let expr sub x =
     | Texp_open (ovf, path, loc, env) ->
       Texp_open (ovf, path, loc, sub.env sub env)
     | Texp_newtype _ as d -> d
-    | Texp_poly cto -> Texp_poly (opt (sub.typ sub) cto)
   in
   let exp_extra = List.map (tuple3 extra id id) x.exp_extra in
   let exp_env = sub.env sub x.exp_env in
@@ -248,8 +247,6 @@ let expr sub x =
         (id, p, sub.expr sub exp1, sub.expr sub exp2, dir, sub.expr sub exp3)
     | Texp_send (exp, meth, expo) ->
       Texp_send (sub.expr sub exp, meth, opt (sub.expr sub) expo)
-    | (Texp_new _ | Texp_instvar _) as d -> d
-    | Texp_setinstvar _ | Texp_override _ -> assert false
     | Texp_letmodule (id, s, mexpr, exp) ->
       Texp_letmodule (id, s, sub.module_expr sub mexpr, sub.expr sub exp)
     | Texp_letexception (cd, exp) ->
diff --git a/compiler/ml/translcore.ml b/compiler/ml/translcore.ml
index df20bb6ca0..12f30a0533 100644
--- a/compiler/ml/translcore.ml
+++ b/compiler/ml/translcore.ml
@@ -911,8 +911,6 @@ and transl_exp0 (e : Typedtree.expression) : Lambda.lambda =
   | Texp_send (expr, Tmeth_name nm, _) ->
     let obj = transl_exp expr in
     Lsend (nm, obj, e.exp_loc)
-  | Texp_new _ | Texp_instvar _ | Texp_setinstvar _ | Texp_override _ ->
-    assert false
   | Texp_letmodule (id, _loc, modl, body) ->
     let defining_expr = !transl_module Tcoerce_none None modl in
     Llet (Strict, Pgenval, id, defining_expr, transl_exp body)
diff --git a/compiler/ml/typecore.ml b/compiler/ml/typecore.ml
index 0b395355f6..1780de9958 100644
--- a/compiler/ml/typecore.ml
+++ b/compiler/ml/typecore.ml
@@ -134,7 +134,7 @@ let iter_expression f e =
     f e;
     match e.pexp_desc with
     | Pexp_extension _ (* we don't iterate under extension point *)
-    | Pexp_ident _ | Pexp_new _ | Pexp_constant _ ->
+    | Pexp_ident _ | Pexp_constant _ ->
       ()
     | Pexp_fun {default = eo; rhs = e} ->
       may expr eo;
@@ -155,10 +155,8 @@ let iter_expression f e =
       List.iter (fun (_, e, _) -> expr e) iel
     | Pexp_open (_, _, e)
     | Pexp_newtype (_, e)
-    | Pexp_poly (e, _)
     | Pexp_lazy e
     | Pexp_assert e
-    | Pexp_setinstvar (_, e)
     | Pexp_send (e, _)
     | Pexp_constraint (e, _)
     | Pexp_coerce (e, _, _)
@@ -177,7 +175,6 @@ let iter_expression f e =
       expr e1;
       expr e2;
       expr e3
-    | Pexp_override sel -> List.iter (fun (_, e) -> expr e) sel
     | Pexp_letmodule (_, me, e) ->
       expr e;
       module_expr me
@@ -1823,7 +1820,6 @@ let rec is_nonexpansive exp =
   | Texp_ifthenelse (_cond, ifso, ifnot) ->
     is_nonexpansive ifso && is_nonexpansive_opt ifnot
   | Texp_sequence (_e1, e2) -> is_nonexpansive e2 (* PR#4354 *)
-  | Texp_new _ -> assert false
   (* Note: nonexpansive only means no _observable_ side effects *)
   | Texp_lazy e -> is_nonexpansive e
   | Texp_letmodule (_, _, mexp, e) ->
@@ -3033,7 +3029,6 @@ and type_expect_ ?type_clash_context ?in_function ?(recarg = Rejected) env sexp
         (Error
            (e.pexp_loc, env, Undefined_method (obj.exp_type, met, valid_methods)))
     )
-  | Pexp_new _ | Pexp_setinstvar _ | Pexp_override _ -> assert false
   | Pexp_letmodule (name, smodl, sbody) ->
     let ty = newvar () in
     (* remember original level *)
@@ -3109,42 +3104,6 @@ and type_expect_ ?type_clash_context ?in_function ?(recarg = Rejected) env sexp
         exp_attributes = sexp.pexp_attributes;
         exp_env = env;
       }
-  | Pexp_poly (sbody, sty) ->
-    let ty, cty =
-      match sty with
-      | None -> (repr ty_expected, None)
-      | Some sty ->
-        let sty = Ast_helper.Typ.force_poly sty in
-        let cty = Typetexp.transl_simple_type env false sty in
-        (repr cty.ctyp_type, Some cty)
-    in
-    if sty <> None then
-      unify_exp_types loc env (instance env ty) (instance env ty_expected);
-    let exp =
-      match (expand_head env ty).desc with
-      | Tpoly (ty', []) ->
-        let exp = type_expect env sbody ty' in
-        {exp with exp_type = instance env ty}
-      | Tpoly (ty', tl) ->
-        (* One more level to generalize locally *)
-        begin_def ();
-        let vars, ty'' = instance_poly true tl ty' in
-        let exp = type_expect env sbody ty'' in
-        end_def ();
-        check_univars env false "method" exp ty_expected vars;
-        {exp with exp_type = instance env ty}
-      | Tvar _ ->
-        let exp = type_exp env sbody in
-        let exp = {exp with exp_type = newty (Tpoly (exp.exp_type, []))} in
-        unify_exp env exp ty;
-        exp
-      | _ -> assert false
-    in
-    re
-      {
-        exp with
-        exp_extra = (Texp_poly cty, loc, sexp.pexp_attributes) :: exp.exp_extra;
-      }
   | Pexp_newtype ({txt = name}, sbody) ->
     let ty = newvar () in
     (* remember original level *)
diff --git a/compiler/ml/typedtree.ml b/compiler/ml/typedtree.ml
index d38c30737e..52a08ef16c 100644
--- a/compiler/ml/typedtree.ml
+++ b/compiler/ml/typedtree.ml
@@ -69,7 +69,6 @@ and exp_extra =
   | Texp_constraint of core_type
   | Texp_coerce of unit * core_type
   | Texp_open of override_flag * Path.t * Longident.t loc * Env.t
-  | Texp_poly of core_type option
   | Texp_newtype of string
 
 and expression_desc =
@@ -119,10 +118,6 @@ and expression_desc =
       * direction_flag
       * expression
   | Texp_send of expression * meth * expression option
-  | Texp_new of unit
-  | Texp_instvar of unit
-  | Texp_setinstvar of unit
-  | Texp_override of unit
   | Texp_letmodule of Ident.t * string loc * module_expr * expression
   | Texp_letexception of extension_constructor * expression
   | Texp_assert of expression
diff --git a/compiler/ml/typedtree.mli b/compiler/ml/typedtree.mli
index 2d10aecc20..5d8819668f 100644
--- a/compiler/ml/typedtree.mli
+++ b/compiler/ml/typedtree.mli
@@ -117,7 +117,6 @@ and exp_extra =
       (** let open[!] M in    [Texp_open (!, P, M, env)]
                                 where [env] is the environment after opening [P]
          *)
-  | Texp_poly of core_type option  (** Used for method bodies. *)
   | Texp_newtype of string  (** fun (type t) ->  *)
 
 and expression_desc =
@@ -221,10 +220,6 @@ and expression_desc =
       * direction_flag
       * expression
   | Texp_send of expression * meth * expression option
-  | Texp_new of unit
-  | Texp_instvar of unit
-  | Texp_setinstvar of unit
-  | Texp_override of unit
   | Texp_letmodule of Ident.t * string loc * module_expr * expression
   | Texp_letexception of extension_constructor * expression
   | Texp_assert of expression
diff --git a/compiler/ml/typedtreeIter.ml b/compiler/ml/typedtreeIter.ml
index 08c2bf1198..008d9cab56 100644
--- a/compiler/ml/typedtreeIter.ml
+++ b/compiler/ml/typedtreeIter.ml
@@ -221,7 +221,6 @@ end = struct
           | Texp_constraint ct -> iter_core_type ct
           | Texp_coerce ((), cty2) -> iter_core_type cty2
           | Texp_open _ -> ()
-          | Texp_poly cto -> option iter_core_type cto
           | Texp_newtype _ -> ()))
       exp.exp_extra;
     (match exp.exp_desc with
@@ -287,7 +286,6 @@ end = struct
       match expo with
       | None -> ()
       | Some exp -> iter_expression exp)
-    | Texp_new _ | Texp_instvar _ | Texp_setinstvar _ | Texp_override _ -> ()
     | Texp_letmodule (_id, _, mexpr, exp) ->
       iter_module_expr mexpr;
       iter_expression exp
diff --git a/compiler/syntax/src/res_ast_debugger.ml b/compiler/syntax/src/res_ast_debugger.ml
index 6013662403..6ed8dbbea4 100644
--- a/compiler/syntax/src/res_ast_debugger.ml
+++ b/compiler/syntax/src/res_ast_debugger.ml
@@ -679,9 +679,6 @@ module SexpAst = struct
       | Pexp_coerce (expr, (), typexpr) ->
         Sexp.list [Sexp.atom "Pexp_coerce"; expression expr; core_type typexpr]
       | Pexp_send _ -> Sexp.list [Sexp.atom "Pexp_send"]
-      | Pexp_new _ -> Sexp.list [Sexp.atom "Pexp_new"]
-      | Pexp_setinstvar _ -> Sexp.list [Sexp.atom "Pexp_setinstvar"]
-      | Pexp_override _ -> Sexp.list [Sexp.atom "Pexp_override"]
       | Pexp_letmodule (mod_name, mod_expr, expr) ->
         Sexp.list
           [
@@ -699,7 +696,6 @@ module SexpAst = struct
           ]
       | Pexp_assert expr -> Sexp.list [Sexp.atom "Pexp_assert"; expression expr]
       | Pexp_lazy expr -> Sexp.list [Sexp.atom "Pexp_lazy"; expression expr]
-      | Pexp_poly _ -> Sexp.list [Sexp.atom "Pexp_poly"]
       | Pexp_newtype (lbl, expr) ->
         Sexp.list
           [Sexp.atom "Pexp_newtype"; string lbl.Asttypes.txt; expression expr]
diff --git a/compiler/syntax/src/res_printer.ml b/compiler/syntax/src/res_printer.ml
index ed6f33b14a..60e302a1cb 100644
--- a/compiler/syntax/src/res_printer.ml
+++ b/compiler/syntax/src/res_printer.ml
@@ -3392,10 +3392,6 @@ and print_expression ~state (e : Parsetree.expression) cmt_tbl =
         Doc.concat [Doc.text "\""; member_doc; Doc.text "\""]
       in
       Doc.group (Doc.concat [parent_doc; Doc.lbracket; member; Doc.rbracket])
-    | Pexp_new _ -> Doc.text "Pexp_new not implemented in printer"
-    | Pexp_setinstvar _ -> Doc.text "Pexp_setinstvar not implemented in printer"
-    | Pexp_override _ -> Doc.text "Pexp_override not implemented in printer"
-    | Pexp_poly _ -> Doc.text "Pexp_poly not implemented in printer"
   in
   let expr_with_await =
     if ParsetreeViewer.has_await_attribute e.pexp_attributes then