Program Definition mapsto_can_store_definition ch v sh (wsh: writable0_share sh) b ofs jm (v':val)
  (MAPSTO: (address_mapsto ch v sh (b, ofs) * TT)%pred (m_phi jm)):
  Memory.mem.

Lemma join_top: forall sh2 sh, join Share.top sh2 sh -> sh = Share.top.