diff --git a/wasm/emit_wast.ml b/wasm/emit_wast.ml
index 546b14e6e..b52279957 100644
--- a/wasm/emit_wast.ml
+++ b/wasm/emit_wast.ml
@@ -2060,11 +2060,7 @@ module ToWasm = struct
     | Struct_get { typ; field } -> C.struct_get typ field arg
     | Struct_get_packed { typ; field; extend } ->
       C.struct_get_packed extend typ field arg
-    | Ref_cast_i31 -> begin
-      match mode with
-      | Reference -> Cst.node "ref.cast" [ Cst.atom "i31"; arg ]
-      | Binarien -> Cst.node "ref.as_i31" [ arg ]
-    end
+    | Ref_cast_i31 -> Cst.node "ref.cast" [ Cst.atom "i31"; arg ]
     | Is_i31 -> Cst.node "ref.test" [ Cst.atom "i31"; arg ]
     | Array_len t -> C.array_len t arg
     | Reinterpret { from_type; to_type } ->
diff --git a/wasm/imports_binaryen.wast b/wasm/imports_binaryen.wast
index 825a63421..b3afba05d 100644
--- a/wasm/imports_binaryen.wast
+++ b/wasm/imports_binaryen.wast
@@ -157,14 +157,14 @@
   (func (export "caml_compare") (param $a (ref eq)) (param $b (ref eq)) (result (ref i31))
     (local $a_block (ref $Gen_block))
     (local $b_block (ref $Gen_block))
-    (if (result (ref i31)) (ref.is_i31 (local.get $a))
+    (if (result (ref i31)) (ref.test i31 (local.get $a))
       (then
-        (if (result (ref i31)) (ref.is_i31 (local.get $b))
+        (if (result (ref i31)) (ref.test i31 (local.get $b))
         (then (return_call $compare_int (local.get $a) (local.get $b)))
         (else (i31.new (i32.const -1))))
       )
       (else
-        (if (result (ref i31)) (ref.is_i31 (local.get $b))
+        (if (result (ref i31)) (ref.test i31 (local.get $b))
         (then (i31.new (i32.const 1)))
         (else
           (local.set $b_block
@@ -212,14 +212,14 @@
   (func $caml_equal (export "caml_equal") (param $a (ref eq)) (param $b (ref eq)) (result (ref i31))
     (local $a_block (ref $Gen_block))
     (local $b_block (ref $Gen_block))
-    (if (result (ref i31)) (ref.is_i31 (local.get $a))
+    (if (result (ref i31)) (ref.test i31 (local.get $a))
       (then
-        (if (result (ref i31)) (ref.is_i31 (local.get $b))
+        (if (result (ref i31)) (ref.test i31 (local.get $b))
         (then (i31.new (ref.eq (local.get $a) (local.get $b))))
         (else (i31.new (i32.const 0))))
       )
       (else
-        (if (result (ref i31)) (ref.is_i31 (local.get $b))
+        (if (result (ref i31)) (ref.test i31 (local.get $b))
         (then (i31.new (i32.const 0)))
         (else
           (local.set $b_block
diff --git a/wasm/wast.ml b/wasm/wast.ml
index 6d5e96e3e..178e2e6a5 100644
--- a/wasm/wast.ml
+++ b/wasm/wast.ml
@@ -247,9 +247,7 @@ module C = struct
   let call func args = node "call" ([ !$(Func_id.name func) ] @ args)
 
   let ref_cast typ arg =
-    let name =
-      match mode with Binarien -> "ref.cast_static" | Reference -> "ref.cast"
-    in
+    let name = "ref.cast" in
     node name ([ type_name typ ] @ arg)
 
   let declare_func f =