diff --git a/core/src/main/java/org/apache/calcite/util/Bug.java b/core/src/main/java/org/apache/calcite/util/Bug.java
index b2f14d76efe8..df9c04eec49d 100644
--- a/core/src/main/java/org/apache/calcite/util/Bug.java
+++ b/core/src/main/java/org/apache/calcite/util/Bug.java
@@ -208,6 +208,12 @@ public abstract class Bug {
    * MILLISECOND and MICROSECOND units in INTERVAL literal</a> is fixed. */
   public static final boolean CALCITE_5422_FIXED = false;
 
+  /** Whether
+   * <a href="https://issues.apache.org/jira/browse/CALCITE-5678">[CALCITE-5678]
+   * Calcite should reject date literals not satisfying Gregorian calendar,
+   * per SQL standard</a> is fixed. */
+  public static final boolean CALCITE_5678_FIXED = false;
+
   /**
    * Use this to flag temporary code.
    */
diff --git a/testkit/src/main/java/org/apache/calcite/test/SqlOperatorTest.java b/testkit/src/main/java/org/apache/calcite/test/SqlOperatorTest.java
index c1bfd6dc055d..fb3da2df5497 100644
--- a/testkit/src/main/java/org/apache/calcite/test/SqlOperatorTest.java
+++ b/testkit/src/main/java/org/apache/calcite/test/SqlOperatorTest.java
@@ -1241,8 +1241,6 @@ void testCastStringToDateTime(CastType castType, SqlOperatorFixture f) {
 
     f.checkScalar("cast('1945-02-24 12:42:25' as TIMESTAMP)",
         "1945-02-24 12:42:25", "TIMESTAMP(0) NOT NULL");
-    f.checkScalar("cast('1945-2-2 12:2:5' as TIMESTAMP)",
-        "1945-02-02 12:02:05", "TIMESTAMP(0) NOT NULL");
     f.checkScalar("cast('  1945-02-24 12:42:25  ' as TIMESTAMP)",
         "1945-02-24 12:42:25", "TIMESTAMP(0) NOT NULL");
     f.checkScalar("cast('1945-02-24 12:42:25.34' as TIMESTAMP)",
@@ -1256,6 +1254,10 @@ void testCastStringToDateTime(CastType castType, SqlOperatorFixture f) {
       f.checkScalar("cast('1945-02-24 12:42:25.34' as TIMESTAMP(2))",
           "1945-02-24 12:42:25.34", "TIMESTAMP(2) NOT NULL");
     }
+    if (Bug.CALCITE_5678_FIXED) {
+      f.checkFails("cast('1945-2-2 12:2:5' as TIMESTAMP)",
+              "Invalid DATE value, '1945-2-2 12:2:5'", true);
+    }
     f.checkFails("cast('nottime' as TIMESTAMP)", BAD_DATETIME_MESSAGE, true);
     f.checkScalar("cast('1241241' as TIMESTAMP)",
         "1241-01-01 00:00:00", "TIMESTAMP(0) NOT NULL");