lp:738091 cast(timestamp() AS time returns NULL for 0000-00-00 00:00:00 in 5.1-micro

mysql-test/r/func_time.result

@@ -1539,3 +1539,9 @@ NULL
 select timestamp(greatest('2002-08-20', '0000-00-00 00:00:00'));
 timestamp(greatest('2002-08-20', '0000-00-00 00:00:00'))
 2002-08-20 00:00:00
+create table t1 (f1 datetime);
+insert into t1 values ('0000-00-00 00:00:00');
+select cast(f1 AS time) from t1;
+cast(f1 AS time)
+00:00:00
+drop table t1;

mysql-test/t/func_time.test

@@ -977,3 +977,12 @@ select day(coalesce(null));
 # lp:738067 Crash in get_datetime_value() in 5.1-micro
 #
 select timestamp(greatest('2002-08-20', '0000-00-00 00:00:00'));
+
+#
+# lp:738091  cast(timestamp() AS time returns NULL for 0000-00-00 00:00:00 in 5.1-micro
+#
+create table t1 (f1 datetime);
+insert into t1 values ('0000-00-00 00:00:00');
+select cast(f1 AS time) from t1;
+drop table t1;
+

sql/field.cc

@@ -5870,10 +5870,10 @@ bool Field_newdate::get_date(MYSQL_TIME *ltime,uint fuzzydate)
   ltime->year=  (tmp >> 9);
   ltime->time_type= MYSQL_TIMESTAMP_DATE;
   ltime->hour= ltime->minute= ltime->second= ltime->second_part= ltime->neg= 0;
-  if ((fuzzydate & TIME_NO_ZERO_DATE) && !tmp)
-    return 1;
-  if (!(fuzzydate & TIME_FUZZY_DATE) && (!ltime->month || !ltime->day))
-    return 1;
+  if (!tmp)
+    return fuzzydate & TIME_NO_ZERO_DATE;
+  if (!ltime->month || !ltime->day)
+    return !(fuzzydate & TIME_FUZZY_DATE);
   return 0;
 }
 
@@ -6003,7 +6003,11 @@ bool Field_datetime::get_date(MYSQL_TIME *ltime, uint fuzzydate)
   ltime->day=		(int) (part1%100);
   ltime->month= 	(int) (part1/100%100);
   ltime->year= 		(int) (part1/10000);
-  return (!(fuzzydate & TIME_FUZZY_DATE) && (!ltime->month || !ltime->day)) ? 1 : 0;
+  if (!tmp)
+    return fuzzydate & TIME_NO_ZERO_DATE;
+  if (!ltime->month || !ltime->day)
+    return !(fuzzydate & TIME_FUZZY_DATE);
+  return 0;
 }
 
 int Field_datetime::cmp(const uchar *a_ptr, const uchar *b_ptr)
@@ -6110,7 +6114,11 @@ bool Field_datetime_hires::get_date(MYSQL_TIME *ltime, uint fuzzydate)
 {
   ulonglong packed= read_bigendian(ptr, Field_datetime_hires::pack_length());
   unpack_time(sec_part_unshift(packed, dec), ltime);
-  return (!(fuzzydate & TIME_FUZZY_DATE) && (!ltime->month || !ltime->day)) ? 1 : 0;
+  if (!packed)
+    return fuzzydate & TIME_NO_ZERO_DATE;
+  if (!ltime->month || !ltime->day)
+    return !(fuzzydate & TIME_FUZZY_DATE);
+  return 0;
 }
 
 uint32 Field_datetime_hires::pack_length() const