Chopping parameters off the head of closures does not seem to work

lib/AstOfLlbc.ml

@@ -1262,15 +1262,7 @@ let expression_of_rvalue (env : env) (p : C.rvalue) : K.expr =
       let fun_ptr = { C.func = C.FunId (FRegular func); generics } in
       let e, _, _ = expression_of_fn_ptr env fun_ptr in
       begin
-        let t, ts = Krml.Helpers.flatten_arrow e.typ in
-        let rec chop_trait_methods = function
-          | K.TBuf _ :: _ as ts -> ts
-          | _ :: ts -> chop_trait_methods ts
-          | _ -> failwith "impossible"
-        in
-        let ts = chop_trait_methods ts in
-        let t = Krml.Helpers.fold_arrow ts t in
-        match t with
+        match e.typ with
         | TArrow ((TBuf (TUnit, _) as t_state), t) ->
             (* Empty closure block, passed by address...? TBD *)
             K.(with_type t (EApp (e, [ with_type t_state (EAddrOf Krml.Helpers.eunit) ])))

test/mismatch/Cargo.toml

@@ -0,0 +1,6 @@
+[package]
+name = "mismatch"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]

test/mismatch/src/main.rs

@@ -0,0 +1,18 @@
+pub trait Operations: Clone + Copy {
+    fn zero() -> Self;
+}
+pub struct MlKemKeyPairUnpacked<const K: usize, Vector: Operations> {
+    x: [Vector; K],
+}
+
+impl<const K: usize, Vector: Operations> MlKemKeyPairUnpacked<K, Vector> {
+    #[inline(always)]
+    pub(crate) fn default() -> Self {
+        Self {
+            x: core::array::from_fn(|_| Vector::zero()),
+        }
+    }
+}
+
+fn main() {
+}