(* not provable at present; see https://github.com/AbsInt/CompCert/issues/207
    for a description of how to solve this problem. *)

Definition samerep (ch1 ch2: memory_chunk) (v1 v2: val) :=
  Memdata.size_chunk ch1 = Memdata.size_chunk ch2 /\
  forall bl: list Memdata.memval,
   Memdata.size_chunk ch1 = Z.of_nat (length bl) ->
   (Memdata.decode_val ch1 bl = v1 <-> Memdata.decode_val ch2 bl = v2).

Lemma mapsto_single_int: forall sh v1 v2 p, is_single v1 -> is_int I32 Unsigned v2 -> samerep Mfloat32 Mint32 v1 v2 -> mapsto sh (Tfloat F32 noattr) p v1 = mapsto sh (Tint I32 Unsigned noattr) p v2.