diff --git a/src/plugins/region/code.ml b/src/plugins/region/code.ml
index 084809d43bd2e06bce04f8841270269b391f166a..1f0b29667abacdf9d1a7a829505506fdb570722c 100644
--- a/src/plugins/region/code.ml
+++ b/src/plugins/region/code.ml
@@ -28,7 +28,7 @@ open Memory
 (* ---  L-Values & Expressions                                            --- *)
 (* -------------------------------------------------------------------------- *)
 
-type value = { from : node option ; ptr : node option }
+type scalar = { from : node option ; ptr : node option }
 let integral = { from = None ; ptr = None }
 let pointer m v =
   match v.ptr with
@@ -57,7 +57,7 @@ and add_loffset (m:map) (s:stmt) (r:node) (ty:typ)= function
 
 and add_value m s e = ignore (add_exp m s e)
 
-and add_exp (m: map) (s:stmt) (e:exp) : value =
+and add_exp (m: map) (s:stmt) (e:exp) : scalar =
   match e.enode with
 
   | AddrOf lv | StartOf lv ->
@@ -120,6 +120,13 @@ let add_instr (m:map) (s:stmt) (instr:instr) =
   match instr with
   | Skip _ | Code_annot _ -> ()
 
+  | Set(lv, { enode = Lval exp }, _) ->
+    let l = add_lval m s lv in
+    let r = add_lval m s exp in
+    Memory.read m l (Lval(s,exp)) ;
+    Memory.write  m l (Lval(s,lv)) ;
+    Memory.merge_copy m ~l ~r
+
   | Set(lv,e,_) ->
     let r = add_lval m s lv in
     let v = add_exp m s e in
diff --git a/src/plugins/region/memory.ml b/src/plugins/region/memory.ml
index d1dd5198156ed560a08d6e5000dfeee44d623134..e10914c98ebc6e5503c32ea4d5adc40d65b3a869 100644
--- a/src/plugins/region/memory.ml
+++ b/src/plugins/region/memory.ml
@@ -444,6 +444,10 @@ let merge (m: map) (a: node) (b: node) : unit =
   failwith_locked m "Region.Memory.merge" ;
   merge_all m [a;b]
 
+let merge_copy (m: map) ~(l: node) ~(r: node) : unit =
+  let { clayout } = get m r in
+  merge_all m [ l; Ufind.make m.store { empty with clayout } ]
+
 (* -------------------------------------------------------------------------- *)
 (* --- Offset                                                             --- *)
 (* -------------------------------------------------------------------------- *)
diff --git a/src/plugins/region/memory.mli b/src/plugins/region/memory.mli
index e15853e9530b642cef5d9dbb5ad2e6ace8314dcb..788ed51359df0959c63ffe2da17495f357ae9c63 100644
--- a/src/plugins/region/memory.mli
+++ b/src/plugins/region/memory.mli
@@ -87,6 +87,7 @@ val shift : map -> node -> Access.acs -> unit
 
 val merge : map -> node -> node -> unit
 val merge_all : map -> node list -> unit
+val merge_copy : map -> l:node -> r:node -> unit
 
 (** @raise Not_found *)
 val lval : map -> lval -> node