Bug #49465 valgrind warnings and incorrect live checksum...

Description:
with a certain number of fields in a table, checksum causes valgrind errors.
more-over, the output of checksum table
5.1.41 valgrind output:
Use of uninitialised value of size 8                       
at: crc32 (crc32.c:289)                                    
by: my_checksum (checksum.c:39)                            
by: mi_checksum (mi_checksum.c:55)                         
by: mi_write (mi_write.c:143)                              
by: ha_myisam::write_row (ha_myisam.cc:780)                
by: handler::ha_write_row(unsigned char*) (handler.cc:4650)
by: write_record (sql_insert.cc:1581)                      
by: mysql_insert (sql_insert.cc:810)                       
by: mysql_execute_command(THD*) (sql_parse.cc:3179)        
by: mysql_parse (sql_parse.cc:5970)                        
by: dispatch_command (sql_parse.cc:1231)                   
by: do_command(THD*) (sql_parse.cc:872)                    

mysql> checksum table t1 quick;
+---------+------------+
| Table   | Checksum   |
+---------+------------+
| test.t1 | 1104745215 | <-------this will be kinda random :-0
+---------+------------+
1 row in set (0.00 sec)

mysql> checksum table t1 extended;
+---------+-----------+
| Table   | Checksum  |
+---------+-----------+
| test.t1 | 467455460 |
+---------+-----------+
1 row in set (0.00 sec)

How to repeat:
run mysqld under valgrind, then:

drop table if exists `t1`;
create table `t1` (
`a` varchar(1),`b` varchar(1),`c` varchar(1),
`f` varchar(1),`g` varchar(1),`h` varchar(1),
`i` varchar(1),`j` varchar(1),`k` varchar(1)
) engine=myisam default charset=latin1 checksum=1;
insert into `t1` values ('','','','','','','','','');
checksum table `t1` quick;    #get the live checksum
checksum table `t1` extended; #recalculate

Verified just as described:

mysql> select version();
+--------------+
| version()    |
+--------------+
| 5.1.43-debug |
+--------------+
1 row in set (0.00 sec)

mysql> drop table if exists `t1`;
Query OK, 0 rows affected (0.00 sec)

mysql> create table `t1` (
    -> `a` varchar(1),`b` varchar(1),`c` varchar(1),
    -> `f` varchar(1),`g` varchar(1),`h` varchar(1),
    -> `i` varchar(1),`j` varchar(1),`k` varchar(1)
    -> ) engine=myisam default charset=latin1 checksum=1;
Query OK, 0 rows affected (0.06 sec)

mysql> insert into `t1` values ('','','','','','','','','');
Query OK, 1 row affected (0.00 sec)

mysql> checksum table `t1` quick;    #get the live checksum
+---------+------------+
| Table   | Checksum   |
+---------+------------+
| test.t1 | 2422371598 |
+---------+------------+
1 row in set (0.00 sec)

mysql> checksum table `t1` extended; #recalculate
+---------+-----------+
| Table   | Checksum  |
+---------+-----------+
| test.t1 | 467455460 |
+---------+-----------+
1 row in set (0.00 sec)

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/93746

2868 Ramil Kalimullin	2009-12-11
      Fix for bug#49465: valgrind warnings and incorrect live checksum...
      
      Problem: writing a record we don't set unused null bits in the
      record buffer in some cases. That may lead to wrong live checksum
      calculation.
      
      Fix: set unused null bits in the record buffer.
     @ mysql-test/r/myisam.result
        Fix for bug#49465: valgrind warnings and incorrect live checksum...
          - test result.
     @ mysql-test/t/myisam.test
        Fix for bug#49465: valgrind warnings and incorrect live checksum...
          - test case.
     @ sql/sql_base.cc
        Fix for bug#49465: valgrind warnings and incorrect live checksum...
          - fillrecord(): set undefined null bits in the record buffer.

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/94273

2868 Ramil Kalimullin	2009-12-16
      Fix for bug#49465: valgrind warnings and incorrect live checksum...
      
      Problem: inserting a record we don't set unused null bits in the
      record buffer if no default field values used.
      That may lead to wrong live checksum calculation.
      
      Fix: set unused null bits in the record buffer in such cases.
     @ mysql-test/r/myisam.result
        Fix for bug#49465: valgrind warnings and incorrect live checksum...
          - test result.
     @ mysql-test/t/myisam.test
        Fix for bug#49465: valgrind warnings and incorrect live checksum...
          - test case.
     @ sql/sql_insert.cc
        Fix for bug#49465: valgrind warnings and incorrect live checksum...
          - set unused null bits to 1 in the record buffer in case we
        don't call restore_record() before a fill_record() call
        (when no default values used).

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/94657

2823 Ramil Kalimullin	2009-12-17
      Fix for bug#49465: valgrind warnings and incorrect live checksum...
      
      Problem: inserting a record we don't set unused null bits in the
      record buffer if no default field values used.
      That may lead to wrong live checksum calculation.
      
      Fix: set unused null bits in the record buffer in such cases.
     @ mysql-test/r/myisam.result
        Fix for bug#49465: valgrind warnings and incorrect live checksum...
          - test result.
     @ mysql-test/t/myisam.test
        Fix for bug#49465: valgrind warnings and incorrect live checksum...
          - test case.
     @ sql/sql_insert.cc
        Fix for bug#49465: valgrind warnings and incorrect live checksum...
          - set unused null bits to 1 in the record buffer in case we
        don't call restore_record() before a fill_record() call
        (when no default values used).

Pushed into 6.0.14-alpha (revid:alik@sun.com-20091219082307-f3i4fn0tm8trb3c0) (version source revid:alik@sun.com-20091217193315-s3ck6ltg8m1zz6r3) (merge vers: 6.0.14-alpha) (pib:15)

Pushed into 5.5.1-m2 (revid:alik@sun.com-20091219082021-f34nq4jytwamozz0) (version source revid:alexey.kopytov@sun.com-20091217150904-ugetvos7v0bo83qe) (merge vers: 5.5.0-beta) (pib:15)

Pushed into mysql-next-mr (revid:alik@sun.com-20091219082213-nhjjgmphote4ntxj) (version source revid:alik@sun.com-20091217191654-rb9sci536v96viaz) (pib:15)

Noted in 5.5.1, 6.0.14 changelogs.

Valgrind warnings for CHECKSUM TABLE were corrected.

Pushed into 5.0.90 (revid:joro@sun.com-20100114082402-05fod2h6z9x9wok8) (version source revid:ramil@mysql.com-20091217055503-x5gma5nmhcgit5em) (merge vers: 5.0.89) (pib:16)

Noted in 5.0.90 changelog.

Setting report to NDI pending push to 5.1.x, Celosia.

Pushed into 5.1.43 (revid:joro@sun.com-20100115085139-qkh0i0fpohd9u9p5) (version source revid:jimw@mysql.com-20091217191514-t4zu0fd4z9534u1q) (merge vers: 5.1.42) (pib:16)

Noted in 5.1.43 changelog.

Setting report to NDI pending push to Celosia.

Pushed into 5.1.44-ndb-7.0.14 (revid:jonas@mysql.com-20100312135944-t0z8s1da2orvl66x) (version source revid:jonas@mysql.com-20100312115609-woou0te4a6s4ae9y) (merge vers: 5.1.44-ndb-7.0.14) (pib:16)

Pushed into 5.1.44-ndb-6.2.19 (revid:jonas@mysql.com-20100312134846-tuqhd9w3tv4xgl3d) (version source revid:jonas@mysql.com-20100312060623-mx6407w2vx76h3by) (merge vers: 5.1.44-ndb-6.2.19) (pib:16)

Pushed into 5.1.44-ndb-6.3.33 (revid:jonas@mysql.com-20100312135724-xcw8vw2lu3mijrhn) (version source revid:jonas@mysql.com-20100312103652-snkltsd197l7q2yg) (merge vers: 5.1.44-ndb-6.3.33) (pib:16)

Fixed in earlier 5.1.x, 5.5.x.