OpenSSL::PKey::EC::Group#==

static VALUE ossl_ec_group_eql(VALUE a, VALUE b)
{
    EC_GROUP *group1 = NULL, *group2 = NULL;

    GetECGroup(a, group1);
    GetECGroup(b, group2);

    switch (EC_GROUP_cmp(group1, group2, ossl_bn_ctx)) {
      case 0: return Qtrue;
      case 1: return Qfalse;
      default: ossl_raise(eEC_GROUP, "EC_GROUP_cmp");
    }
}