Re: [PATCH] compat: Allow static initializer for pthreads on Windows

On Fri, Oct 28, 2016 at 6:01 AM, Philip Oakley [off-list ref] wrote:

From: "Johannes Sixt" <redacted>

quoted

One point is that the DCLP idiom must be implemented correctly. There are
solutions, of course, and when the initialization is over, we have a
miniscule overhead at each pthread_mutex_lock call.

I had to look up DCLP ( = Double Checked Locking Patterns), and found a good
write up on the issues..

http://www.aristeia.com/Papers/DDJ_Jul_Aug_2004_revised.pdf "C++ and the
Perils of Double-Checked Locking", which include 'C' issues, and
multi-thread, multi-processor issues. Not an easy issue when fighting
optimisers..

--

Philip

Yep, this is why we have memory barriers. Ofcourse languages like C
don't really allow you to express them in the language and we restore
to various platform specific methods.

Thanks,
Jake