diff --git a/compiler/obc/obc.ml b/compiler/obc/obc.ml
index b84f519..528aa6c 100644
--- a/compiler/obc/obc.ml
+++ b/compiler/obc/obc.ml
@@ -89,6 +89,7 @@ and block =
 and var_dec =
     { v_ident : var_ident;
       v_type : ty;
+      v_alias : bool; (* this var_dec only declare a const pointer, no allocation is done *)
       v_linearity : linearity;
       v_mutable : bool;
       v_loc : location }
diff --git a/compiler/obc/obc_utils.ml b/compiler/obc/obc_utils.ml
index 9988f8b..178bd84 100644
--- a/compiler/obc/obc_utils.ml
+++ b/compiler/obc/obc_utils.ml
@@ -17,8 +17,9 @@ open Obc
 open Obc_mapfold
 open Global_mapfold
 
-let mk_var_dec ?(loc=no_location) ?(linearity = Ltop) ?(mut=false) ident ty =
-  { v_ident = ident; v_type = ty; v_linearity = linearity; v_mutable = mut; v_loc = loc }
+let mk_var_dec ?(loc=no_location) ?(linearity = Ltop) ?(mut=false) ?(alias=false) ident ty =
+  { v_ident = ident; v_type = ty; v_linearity = linearity;
+    v_alias = alias; v_mutable = mut; v_loc = loc }
 
 let mk_ext_value ?(loc=no_location) ty desc =
   { w_desc = desc; w_ty = ty; w_loc = loc; }