Bug #48098 Valgrind - uninitialized value - os_thread_eq (os0thread.c:56)
Submitted: 15 Oct 2009 19:35 Modified: 27 Oct 2009 23:08
Reporter: Patrick Crews Email Updates:
Status: Can't repeat Impact on me:
None 
Category:MySQL Server: Partitions Severity:S3 (Non-critical)
Version:5.5 WL#3352 OS:Any
Assigned to: Mikael Ronström CPU Architecture:Any
Tags: uninitialized value, valgrind
Triage: Triaged: D2 (Serious)

[15 Oct 2009 19:35] Patrick Crews
Description:
Valgrind error produced from running the RQG with the partition_pruning grammar:

494:==15631== Conditional jump or move depends on uninitialised value(s)
495:==15631==    at 0x8B9DB78: os_thread_eq (os0thread.c:56)
496:==15631==    by 0x8C4CD05: rw_lock_x_lock_low (sync0rw.c:569)
497:==15631==    by 0x8C4D19C: rw_lock_x_lock_func (sync0rw.c:666)
498:==15631==    by 0x8CC045C: btr_search_update_hash_on_delete (btr0sea.c:1504)
499:==15631==    by 0x8CAAE28: btr_cur_optimistic_delete (btr0cur.c:2831)
500:==15631==    by 0x8C0EBF3: row_purge_remove_sec_if_poss_low (row0purge.c:286)
501:==15631==    by 0x8C0EF99: row_purge_remove_sec_if_poss (row0purge.c:317)
502:==15631==    by 0x8C0F35D: row_purge_del_mark (row0purge.c:364)
503:==15631==    by 0x8C1089D: row_purge (row0purge.c:641)
504:==15631==    by 0x8C10B17: row_purge_step (row0purge.c:684)
505:==15631==    by 0x8BD3984: que_thr_step (que0que.c:1240)
506:==15631==    by 0x8BD3FFB: que_run_threads_low (que0que.c:1303)
507:==15631==    by 0x8BD4417: que_run_threads (que0que.c:1340)
508:==15631==    by 0x8C59B35: trx_purge (trx0purge.c:1139)
509:==15631==    by 0x8C3E9BD: srv_master_thread (srv0srv.c:2510)
510:==15631==    by 0x403F4FE: start_thread (in /lib/tls/i686/cmov/libpthread-2.9.so)

How to repeat:
Use the RQG:
perl ./runall.pl --basedir=<path>/mysql-5.4 --gendata=conf/partition_pruning.zz
--threads=1 --valgrind --Validator=MarkErrorLog --queries=10000
--grammar=conf/partition_pruning.yy

This was done with the row count (in partition_pruning.zz) at 10000

Queries + valgrind errors will be in the error log
[27 Oct 2009 23:08] Patrick Crews
Unable to repeat this bug with the latest version of the tree.