A MariaDB server configured with --with-debug=full has the following differences from a normal MariaDB server:

• You can have maximum of 1000 tables locked at the same time in one statement. (Define MAX_LOCKS in mysys/thrlock.c). This is to detect loops in the used lists.
• You can have maximum of 1000 threads locking the same table. (Define MAX_THREADS in mysys/thrlock.c). This is to detect loops in the used lists.
• Deadlock detection of mutex will be done at runtime. If wrong mutex handling is found an error will be printed to the error log. (Define SAFE_MUTEX)
• Memory overrun/underrun and not freed memory will be reported to the error log (Define SAFEMALLOC)
• You can get a trace of what mysqld (and most other binaries) is doing by starting it with the --debug option. The trace is usually put in /tmp or C:\