pthread_cond_timedwait() in PosixCond.hxx:timed_wait(PosixMutex...) returns
EINVAL, if ts.tv_nsec >= 1E9. In this case, it returns to early.
Find attached a patch which fixes this. I chose a compare-subtraction method
to keep ts.tv_nsec below 1E9.
Another option would be
ts.tv_sec += ts.tv_nsec / 1000000000;
ts.tv_nsec %= 1000000000;
But I guess this takes more time on some ARM processors, which don't support
hardware division.
Apparently all other C libraries are not compatible with "constexpr".
Those which are not will get a performance penalty, but at least they
work at all.
On NetBSD, PTHREAD_MUTEX_INITIALIZER and PTHREAD_COND_INITIALIZER are
not compatible with C++11 "constexpr" (see Mantis ticket 0004110). As
a workaround, don't ues "constexpr", and use the functions
pthread_mutex_init(), pthread_mutex_destroy(), pthread_cond_init() and
pthread_cond_destroy() instead. This adds some runtime overhead, but
is portable to POSIX implementations that have awkward initializer
macros.
