Update charon

charon-pin

@@ -1,2 +1,2 @@
 # This is the commit from https://github.com/AeneasVerif/charon that should be used with this version of aeneas.
-cb50ff16b9f1066b8a97dc06da704de2da2fa41c
+527ea8e3b5dcb52edd6aef0f7bc34cc09c11dd59

src/PrePasses.ml

@@ -1712,6 +1712,7 @@ let replace_static (crate : crate) : crate =
               {
                 index = RegionId.of_int 1;
                 name = Some "'b";
+                variance = VaUnknown;
                 mutability = LtUnknown;
               };
             ];

src/interp/InterpUtils.ml

@@ -929,7 +929,13 @@ let instantiate_fun_sig (span : Meta.span option) (ctx : eval_ctx)
       let fresh_regions = fresh_regions in
       let fresh_region_vars : region_param list =
         List.map
-          (fun index -> { Types.index; name = None; mutability = LtUnknown })
+          (fun index ->
+            {
+              Types.index;
+              name = None;
+              variance = VaUnknown;
+              mutability = LtUnknown;
+            })
           fresh_regions
       in
       let open Substitute in

src/llbc/Builtin.ml

@@ -45,14 +45,20 @@ module Sig = struct
 
   (** Region 'a of id 0 *)
   let region_param_0 : region_param =
-    { index = rvar_id_0; name = Some "'a"; mutability = LtUnknown }
+    {
+      index = rvar_id_0;
+      name = Some "'a";
+      variance = VaUnknown;
+      mutability = LtUnknown;
+    }
 
   (** Region group: [{ parent={}; regions:{'a of id 0} }] *)
   let region_group_0 : region_var_group =
     { id = rg_id_0; regions = [ rvar_id_0 ]; parents = [] }
 
   (** Type parameter [T] of id 0 *)
-  let type_param_0 : type_param = { index = tvar_id_0; name = "T" }
+  let type_param_0 : type_param =
+    { index = tvar_id_0; name = "T"; variance = VaUnknown }
 
   let usize_ty : ty = TLiteral (TUInt Usize)
 

src/symbolic/SymbolicToPureTypes.ml

@@ -215,7 +215,7 @@ let translate_strait_type_constraint (span : Meta.span option)
   { trait_ref; type_id; ty }
 
 let translate_type_param (p : T.type_param) : type_param =
-  let { index; name } : T.type_param = p in
+  let { index; name; variance = _ } : T.type_param = p in
   { index; name }
 
 let translate_generic_params (span : Meta.span option)