Subj : Re: Can C++ local static objects be made thread safe?
To   : comp.programming.threads
From : Marcin 'Qrczak' Kowalczyk
Date : Fri Feb 04 2005 11:25 am

Alexander Terekhov <terekhov@web.de> writes:

> The thing is that not all local statics are immutable

If they are mutable, then operations which change them need
synchronization *in adition to* initialization.

> and/or need thread-safe init provided by implementation to
> begin with.

If they are initialized lazily and this may happen from multiple
thread simultaneously, then synchronization is needed. Otherwise
it's harmless.

If you don't want lazy initialization with its overhead (an overhead
of checking whether it's initialized is present even without threads),
just move the variable outside the function - it will be initialized
on program startup.

-- 
   __("<         Marcin Kowalczyk
   \__/       qrczak@knm.org.pl
    ^^     http://qrnik.knm.org.pl/~qrczak/

.