Log Message:
Changes 5.5.38:

Bugs Fixed

InnoDB: For each insert, memset would be called three times to allocate memory \ 
for system fields. To reduce CPU usage, the three memset calls are now combined \ 
into a single call.

Replication: When used on a table employing a transactional storage engine, a \ 
failed TRUNCATE TABLE was still written to the binary log and thus replayed on \ 
the slave. This could lead to inconsistency when the master retained data that \ 
was removed on the slave.

Now in such cases TRUNCATE TABLE is logged only when it executes successfully.

Certain INFORMATION_SCHEMA queries could cause a server exit.

For indexes on prefixes or character string columns, index corruption could \ 
occur for assignment of binary data to the column due to improper character \ 
counting.

Solaris-specific scripts were included in and installed by non-Solaris packages.

EXPLAIN on a query with an EXISTS subquery containing a UNION could cause a \ 
server exit. Multiple executions of a prepared EXPLAIN on a UNION of subqueries \ 
could cause a server exit.

Executing a correlated subquery on an ARCHIVE table which has an AUTO_INCREMENT \ 
column caused the server to hang.

The client library could cause clients to exit due to incorrectly mapping the \ 
client error number to the corresponding message, if reallocation of packet \ 
buffer memory occurred.

Calling mysql_get_server_version() with an invalid connection handler argument \ 
caused the client to exit. Now it returns 0 and reports a \ 
CR_COMMANDS_OUT_OF_SYNC error.

On Windows, calling mysql_thread_init() call without mysql_init() caused the \ 
client to exit. windows. Now it returns a nonzero result because it is an error \ 
to call mysql_thread_init() before the client library is initialized with \ 
mysql_library_init().

CMake produced not-useful warnings about INTERFACE_LINK_LIBRARIES policy.

LOAD DATA LOCAL INFILE could use all CPU if import errors occurred when there \ 
were no line delimiters.

A statement of the following form broke row-based replication because it created \ 
a table having a field of data type BIGINT with a display width of 3000, which \ 
is beyond the maximum acceptable value of 255:

CREATE TABLE t1 AS SELECT REPEAT('A',1000) DIV 1 AS a;