Proof with eauto with val_renamings.
intros.
destruct v1, v1'; inversion Hval_obs;
inversion Hval_obs'; subst;
solve [simpl; eauto with val_renamings].
Qed.

Lemma val_obs_offset_ptr:
forall f v1 v2 ofs
(Hval_obs: val_obs f v1 v2),
val_obs f (Val.offset_ptr v1 ofs) (Val.offset_ptr v2 ofs).