Log Message:
Changes 5.5.39:

CMake support was updated to handle CMake version 3.

The timed_mutexes system variable has no effect and is deprecated.

Bugs Fixed

InnoDB: Opening a parent table that has thousands of child tables could result \ 
in a long semaphore wait condition.

Partitioning: Selecting from a table having multiple columns in its primary key \ 
and partitioned by LIST COLUMNS(R), where R was the last (rightmost) column \ 
listed in the primary key definition, returned an incorrect result.

Replication: When using row-based replication, updating or deleting a row on the \ 
master that did not exist on the slave led to failure of the slave when it tried \ 
to process the change. This problem occurred with InnoDB tables lacking a \ 
primary key.

Replication: Quotation marks were not always handled correctly by LOAD DATA \ 
INFILE when written into the binary log.

Replication: A group of threads involved in acquiring locks could deadlock when \ 
the following events occurred:

Dump thread reconnects from slave; on master, a new dump thread tries to kill \ 
zombie dump threads; having acquired the thread's LOCK_thd_data, it is about to \ 
acquire LOCK_log.

Application thread executing show binary logs, having acquired LOCK_log and \ 
about to acquire LOCK_index.

Application thread executing PURGE BINARY LOGS; having acquired LOCK_index, it \ 
is about to acquire LOCK_thread_count.

Application thread executing SHOW PROCESSLIST (or SELECT * FROM \ 
INFORMATION_SCHEMA.PROCESSLIST), having acquired LOCK_thread_count and about to \ 
acquire the zombie dump thread's LOCK_thd_data.