Log Message:
Changes 5.5.40:
InnoDB: An ALTER TABLE ... ADD FOREIGN KEY operation could cause a serious error.
InnoDB: With a transaction isolation level less than or equal to READ COMMITTED, \ 
gap locks were not taken when scanning a unique secondary index to check for \ 
duplicates. As a result, duplicate check logic failed allowing duplicate key \ 
values in the unique secondary index.
InnoDB: During recovery, a segmentation fault would occur when marking a table \ 
as corrupt.
yaSSL client code did not validate the encryption size or session ID length, \ 
which could cause the client to exit.
MySQL installation from RPM packages could fail if Postfix had been installed \ 
using yum.
yaSSL could fail preauthorization if the client supplied inaccurate buffer lengths.
Competition between threads could lead to timeout failure trying to rotate the \ 
audit log file.
On Linux (OEL6), if Sun DTrace was installed, the MySQL build failed.
LPAD() and RPAD() could cause a server exit if the pad string argument was not \ 
well formed.
The optimizer could create a zero-length column for a temporary table, causing a \ 
server exit.