Fix for bug #13044: BIT_COUNT with NULL values.

sql/item_func.cc:
  Fix for bug #13044: BIT_COUNT with NULL values.
  Always set null_value.

1 files changed, 12 insertions, 0 deletions

diff --git a/mysql-test/t/func_op.test b/mysql-test/t/func_op.test
index a312d6ac8c0..ab96caaff82 100644
--- a/mysql-test/t/func_op.test
+++ b/mysql-test/t/func_op.test
@@ -14,3 +14,15 @@ select  1 | -1,  1 ^ -1,  1 & -1;
 select  0 | -1,  0 ^ -1,  0 & -1;
 select -1 >> 0, -1 << 0;
 select -1 >> 1, -1 << 1;
+
+#
+# Bug 13044: wrong bit_count() results
+#
+
+drop table if exists t1,t2;
+create table t1(a int);
+create table t2(a int, b int);
+insert into t1 values (1), (2), (3);
+insert into t2 values (1, 7), (3, 7);
+select t1.a, t2.a, t2.b, bit_count(t2.b) from t1 left join t2 on t1.a=t2.a;
+drop table t1, t2;