Local Open Scope assert.
Definition Gprog : funspecs :=
ltac:(with_library prog [odd_spec; even_spec; main_spec]).

(* Specifications: *)
Lemma body_even : semax_body Vprog Gprog f_even even_spec.
Lemma body_main : semax_body Vprog Gprog f_main main_spec.
Definition Espec := add_funspecs NullExtension.Espec (ext_link_prog even.prog) Gprog.