# Functionality Added or Changed
* Replication: The variable binlogging_impossible_mode has been renamed binlog_error_action. binlogging_impossible_mode is now deprecated.
* The new -DWITH_UBSAN=ON CMake option enables the Undefined Behavior Sanitizer. This feature is supported by GCC 4.9 and up, and Clang 3.4 and up.
# Bugs Fixed
* InnoDB: An ALTER TABLE operation raised an assertion. When a foreign key object was removed from the dictionary cache, an incorrect foreign key object was removed from the rb-tree.
...See Full Release Notes