This is a little off the subject, but related to discussions of
double-check and its variants. Maybe everyone else already knew this,
but it was surprising to me.
As far as I can see (I also checked with Doug Schmidt), there is
no way to statically initialize a WIN32 CRITICAL_SECTION lock in C.
In posix, this can be done via:
static pthread_mutex_t amutex = PTHREAD_MUTEX_INITIALIZER;
But in WIN32, you need to call InitializeCriticalSection() before you
can use a lock. This makes it exceedingly tricky to define static
singletons that need a static lock to protect construction. Trying to
use double-check for the static lock itself of course leads to
infinite regress. So I guess you'd need to roll-your-own
dekker-algorithm locks or use raw CAS or test-and-set or somesuch? I
wonder how many people get this right. Or maybe there is some
In C++, you can wrap the CRITICAL_SECTION in a class that that will
initialize it upon construction (as in ACE, and Schmidt et al's POSA2
book). But even in this case, I don't know if C++ officially requires,
and win32 runtimes actually provide, enough static initialization
safeguards for this to occur reliably?
JavaMemoryModel mailing list - http://www.cs.umd.edu/~pugh/java/memoryModel
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