Memory alignment issue. mutex has to ablligned?

[shlomots]

I have a class that wraps the Zephyr implementation of a mutex. For some reason, when the code runs, I get this error:

ASSERTION FAIL [mutex->lock_count > 0U] @ WEST_TOPDIR/zephyr/kernel/mutex.c:239

If I add __align(8) to the wrapper class, the problem is fixed and the code runs perfectly.
Does Zephyr's mutex implementation have to be aligned?

Thanks in advance, 
Shlomo