Definition mem_wd' m m' := forall b ofs, memval_inject (Mem.flat_inj (Mem.nextblock m))
    (ZMap.get ofs (PMap.get b (Mem.mem_contents m'))) (ZMap.get ofs (PMap.get b (Mem.mem_contents m'))).

Lemma mem_wd'_alloc_global: forall {F V} (ge: Genv.t F V) a m m0 m1 (GA: Genv.alloc_global ge m0 a = Some m1), mem_wd' m m0 -> valid_genv ge m -> mem_wd' m m1.