I added cmake support for the thread sanitizer (address sanitizer was already 
there). Use:

make cmake -j YES_THREAD_SANITIZER=1 # (or YES_ADDRESS_SANITIZER=1)

However, thread sanitizer is broken on U-24, programs refuse to start ("FATAL: 
ThreadSanitizer: unexpected memory mapping") and report what looks like bogus 
complaints about mutexes ("unlock of an unlocked mutex (or by a wrong thread)").

On macos, thread sanitizer does not report any errors or warnings or ...

P.S.

The Undefined Behaviour Sanitizer (UBSAN) complained about a few places where 
functions could have been called with a NULL pointer arguments, I added some 
assert()s to make it happy.

K.O.