CFLAGS in libc_r, libpthread and libthr, and MUTEX stuff in kern_mutex.c

[Conrad Sabatier]

Given that STABLE is supposed to be...well...*stable* :-) ...

Could we possibly remove "-D_PTHREADS_INVARIANTS", "-D_LOCK_DEBUG" and "-g"
from the CFLAGS in the Makefiles for libc_r, libpthread and libthr?  I've
been under the impression that these options were only intended for
testing/debugging under CURRENT.

Granted, it's a simple matter to patch the Makefiles after an update/before
a buildworld, but it would be nice not to have to do so.

On a related note, I was rather surprised to discover recently that in
sys/kern/kern_mutex.c, the MUTEX_WAKE_ALL option is forcibly defined if not
already defined in the user's kernel config.  While the accompanying
comment (in mutex.c) would seem to indicate that there's good reason for
doing so at this time, at the very least, this should be documented in
sys/conf/NOTES as well.
 
Additionally, it should also be made unmistakably clear that certain other
mutex-related options -- namely, ADAPTIVE_GIANT and NO_ADAPTIVE_MUTEXES --
have absolutely no effect whatsoever unless SMP is also defined.  While I
suppose this might be inferred from the fact that they're listed under the
SMP section of NOTES, nonetheless, there is a chance that this relationship
may go unrecognized.

Thank you.

-- 
Conrad J. Sabatier <conrads at cox.net> -- "In Unix veritas"