From 022e2ef800a333cb37eb783f83c480770587f57b Mon Sep 17 00:00:00 2001
From: Sergey Glukhov <Sergey.Glukhov@sun.com>
Date: Wed, 9 Jun 2010 16:17:18 +0400
Subject: [PATCH] Bug#38999 valgrind warnings for update statement in function
 compare_record() (InnoDB plugin branch)

mysql-test/suite/innodb_plugin/r/innodb_mysql.result:
  test case
mysql-test/suite/innodb_plugin/t/innodb_mysql.test:
  test case
storage/innodb_plugin/row/row0sel.c:
  init null bytes with default values as they might be
  left uninitialized in some cases and these uninited bytes
  might be copied into mysql record buffer that leads to
  valgrind warnings on next use of the buffer.
---
 .../suite/innodb_plugin/r/innodb_mysql.result       | 12 ++++++++++++
 mysql-test/suite/innodb_plugin/t/innodb_mysql.test  | 13 +++++++++++++
 storage/innodb_plugin/row/row0sel.c                 |  6 ++++++
 3 files changed, 31 insertions(+)

diff --git a/mysql-test/suite/innodb_plugin/r/innodb_mysql.result b/mysql-test/suite/innodb_plugin/r/innodb_mysql.result
index 2bf1ef8fbf0..b4ac88fc1c3 100644
--- a/mysql-test/suite/innodb_plugin/r/innodb_mysql.result
+++ b/mysql-test/suite/innodb_plugin/r/innodb_mysql.result
@@ -2378,4 +2378,16 @@ SELECT SECOND(c)-@bug47453 FROM t1 JOIN t2 ON d=a;
 SECOND(c)-@bug47453
 0
 DROP TABLE t1, t2;
+#
+# Bug#38999 valgrind warnings for update statement in function compare_record()
+#
+CREATE TABLE t1 (a INT PRIMARY KEY) ENGINE=InnoDB;
+CREATE TABLE t2 (a INT PRIMARY KEY) ENGINE=InnoDB;
+INSERT INTO t1 values (1),(2),(3),(4),(5);
+INSERT INTO t2 values (1);
+SELECT * FROM t1 WHERE a = 2;
+a
+2
+UPDATE t1,t2 SET t1.a = t1.a + 100 WHERE t1.a = 1;
+DROP TABLE t1,t2;
 End of 5.1 tests
diff --git a/mysql-test/suite/innodb_plugin/t/innodb_mysql.test b/mysql-test/suite/innodb_plugin/t/innodb_mysql.test
index c80db7088ab..3f6d9d96bb8 100644
--- a/mysql-test/suite/innodb_plugin/t/innodb_mysql.test
+++ b/mysql-test/suite/innodb_plugin/t/innodb_mysql.test
@@ -618,5 +618,18 @@ SELECT SECOND(c)-@bug47453 FROM t1 JOIN t2 ON d=a;
 
 DROP TABLE t1, t2;
 
+--echo #
+--echo # Bug#38999 valgrind warnings for update statement in function compare_record()
+--echo #
+
+CREATE TABLE t1 (a INT PRIMARY KEY) ENGINE=InnoDB;
+CREATE TABLE t2 (a INT PRIMARY KEY) ENGINE=InnoDB;
+INSERT INTO t1 values (1),(2),(3),(4),(5);
+INSERT INTO t2 values (1);
+
+SELECT * FROM t1 WHERE a = 2;
+UPDATE t1,t2 SET t1.a = t1.a + 100 WHERE t1.a = 1;
+
+DROP TABLE t1,t2;
 
 --echo End of 5.1 tests
diff --git a/storage/innodb_plugin/row/row0sel.c b/storage/innodb_plugin/row/row0sel.c
index a5bf361661b..2861235a995 100644
--- a/storage/innodb_plugin/row/row0sel.c
+++ b/storage/innodb_plugin/row/row0sel.c
@@ -2678,6 +2678,12 @@ row_sel_store_mysql_rec(
 		prebuilt->blob_heap = NULL;
 	}
 
+	/* init null bytes with default values as they might be
+	left uninitialized in some cases and these uninited bytes
+	might be copied into mysql record buffer that leads to
+	valgrind warnings */
+	memcpy(mysql_rec, prebuilt->default_rec, prebuilt->null_bitmap_len);
+
 	for (i = 0; i < prebuilt->n_template; i++) {
 
 		templ = prebuilt->mysql_template + i;