aff_pt_montgomery_init
ATTRIBUTE_WARN_UNUSED_RET int aff_pt_montgomery_init(aff_pt_montgomery_t in, ec_montgomery_crv_src_t curve);
ret = aff_pt_montgomery_init(out_montgomery, montgomery_crv); EG(ret, err);
ret = aff_pt_montgomery_init(out, in->crv); EG(ret, err);
ret = aff_pt_montgomery_init(out_montgomery, montgomery_crv); EG(ret, err);
ret = aff_pt_montgomery_init(in, curve); EG(ret, err);