Instance CompSpecs : compspecs. make_compspecs prog. Defined.
Definition Vprog : varspecs. mk_varspecs prog. Defined.
Local Open Scope logic.
Definition f_spec :=
DECLARE _f
WITH p: val, q:val, sh: share
PRE  [_p OF tptr tint, _q OF tptr tint]
PROP (sepalg.nonidentity sh)
LOCAL(temp _p p; temp _q q)
SEP(data_at sh tint (Vint Int.zero) p; data_at sh tint (Vint Int.zero) q)
POST [ tint ]
PROP()
LOCAL (temp 1%positive (Vint (if eq_dec p q then Int.one else Int.zero)))
SEP (data_at sh tint (Vint Int.zero) p; data_at sh tint (Vint Int.zero) q).
Definition Gprog : funspecs := nil.

Lemma body_f: semax_body Vprog Gprog f_f f_spec.