MySQL Bugs: #27676: Falcon: crash if show mutex status

Bug #27676	Falcon: crash if show mutex status
Submitted:	5 Apr 2007 20:09	Modified:	5 Apr 2007 22:04
Reporter:	Peter Gulutzan	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server: Falcon storage engine	Severity:	S3 (Non-critical)
Version:	5.2.4-falcon-alpha-debug	OS:	Linux (SUSE 10 64-bit)
Assigned to:	Hakan Küçükyılmaz	CPU Architecture:	Any

Description:
If I say "show mutex status;" with 5.2-4-falcon-alpha-debug,
crash.

The crash doesn't happen with a recent 5.1 build (without Falcon).

ChangeSet@1.2557, 2007-04-05 18:16:09+02:00

How to repeat:
pgulutzan@linux:~> /usr/local/mysql/bin/mysql --user=root
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.2.4-falcon-alpha-debug Source distribution

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> show mutex status;
ERROR 2013 (HY000): Lost connection to MySQL server during query

If InnoDB is disabled, then there is no crash:

[23:50] root@(none)>show mutex status;
ERROR 1286 (42000): Unknown table engine 'InnoDB'

If InnoDB is enabled, then it we following assertion:

Program received signal SIGABRT, Aborted.
[Switching to Thread 1133021536 (LWP 12551)]
0x00002b4f8f5bb07b in raise () from /lib/libc.so.6
(gdb) bt
#0  0x00002b4f8f5bb07b in raise () from /lib/libc.so.6
#1  0x00002b4f8f5bc84e in abort () from /lib/libc.so.6
#2  0x00002b4f8f5b4af4 in __assert_fail () from /lib/libc.so.6
#3  0x00000000006a5020 in MYSQLparse (yythd=0x1904a08) at sql_yacc.yy:8853
#4  0x000000000067cfeb in mysql_parse (thd=0x1904a08, inBuf=0x1933708 "show mutex status", length=17)
    at sql_parse.cc:5247
#5  0x000000000067ddb0 in dispatch_command (command=COM_QUERY, thd=0x1904a08,
    packet=0x192b679 "show mutex status", packet_length=18) at sql_parse.cc:896
#6  0x000000000067f15e in do_command (thd=0x1904a08) at sql_parse.cc:662
#7  0x000000000066d190 in handle_one_connection (arg=0x1904a08) at sql_connect.cc:1089
#8  0x00002b4f8efa0f1a in start_thread () from /lib/libpthread.so.0
#9  0x00002b4f8f655602 in clone () from /lib/libc.so.6
#10 0x0000000000000000 in ?? ()
(gdb)

Assertion was hit by another case of version number faking madness for 5.1-falcon.

5.1-falcon is using version number 5.2.xyz and therefore was hitting following assertion:

WARN_DEPRECATED(yythd, "5.2", "SHOW MUTEX STATUS", "'SHOW ENGINE INNODB MUTEX'");

Fixed in latest bk.