> Unfortunatly, due to alignment the NPTL pthread_cond_t grows larger
> than the Linuxthreads version when I add the padding. This is the only
> structure the grows larger in size than before. Is there any way I can
> avoid adding the padding?
It looks to me like you have one word to spare. That's all you really
need. That word will only ever be 1 from old PTHREAD_COND_INITIALIZER.
Checking all three padding words is really just paranoia trying to
distinguish clobbered structs from old initialized data.