MySQL Bugs: #1826: Server crashed when a table opened with HANDLER is altered

Bug #1826	Server crashed when a table opened with HANDLER is altered
Submitted:	12 Nov 2003 23:55	Modified:	18 Nov 2003 13:05
Reporter:	Pascal Drecker	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server	Severity:	S2 (Serious)
Version:	4.0.16	OS:	Windows (WInXP)
Assigned to:	Sergei Golubchik	CPU Architecture:	Any

Description:
The MySQL-Server crashed while one process has opened a table with the HANDLER command and another process alters this table!

(If you use one process the HANDLER of the opened table goes invalid after the table is altered.)

Best Regards from the University of Greifswald (Germany),
Pascal

How to repeat:
first process: HANDLER test1 OPEN;
second process: ALTER TABLE test1 ADD mytestcol char(20);

RESULT: Server is crashing!

Now I am searching for a workaround: 'LOCK TABLES test1 WRITE' does not fail although this table is already opened by 'HANDLER test1 OPEN'.

I think this is another bug because 'HANDLER test1 OPEN' failed if the table is already locked!

Best Regards,
Pascal

Thread1: HANDLER tablename OPEN;
Thread2: ALTER TABLE tablename ADD col int;
Thread1: HANDLER tablename READ FIRST;
mysqld crashes.

Error log shows:
runtime error R6025
- pure virtual function call

Thank you for your bug report. This issue has been committed to our
source repository of that product and will be incorporated into the
next release.

If necessary, you can access the source repository and build the latest
available version, including the bugfix, yourself. More information 
about accessing the source trees is available at
    http://www.mysql.com/doc/en/Installing_source_tree.html

fixed in 4.0.17