k5_size_auth_context
k5_size_auth_context(krb5_auth_context auth_context, size_t *sizep);
kret = k5_size_auth_context(ctx->auth_context, &required);
if (!k5_size_auth_context(auth_context, &required) &&
check(k5_size_auth_context(actx2, &elen2));
check(k5_size_auth_context(actx, &elen));