static bool stacksafe(struct bpf_verifier_env *env, struct bpf_func_state *old,
		      struct bpf_func_state *cur, struct bpf_idmap *idmap, bool exact)
static bool stacksafe(struct bpf_verifier_env *env, struct bpf_func_state *old,
		      struct bpf_func_state *cur, struct bpf_idmap *idmap,
		      enum exact_level exact)