@Test
  public void testKnownPriorErrors() {

    // Regression test for defect reported in HIVE-6243
    long a = 213474114411690L;
    long b = 5062120663L;
    verifyMultiplyDivideInverse(a, b);

    // Regression test for defect reported in HIVE-6399
    String a2 = "-605044214913338382";  // 18 digits
    String b2 = "55269579109718297360"; // 20 digits

    // -33440539101030154945490585226577271520 is expected result
    verifyHighPrecisionMultiplySingle(a2, b2);
  }
During earlier code testing, if we found errors, test them here as regression tests.
common/src/test/org/apache/hadoop/hive/common/type/TestDecimal128.java