Hurd, Matthew wrote:
Behalf Of scott Assume use of a technique like the following (think this has been presented as "object shim"?);
T & anastasia() { static T *p = new T; return *p; }
as a means of dealing with global construction issue, i.e. instead of expressions like "anastasia.data_member" the usage is "anastasia().data_member". Also assume that some of these global objects (i.e. shims) deploy mutexes for MT reasons. What happens when there is more that one thread running around making calls to shims? Instantiation of the global itself becomes an MT issue.
That's what the double-checked locking pattern for singletons is for.
Regards,
Matt Hurd.
No, the double-checked locking pattern is only good as the subject of talks describing why it's not good for anything. http://www.nwcpp.org/Downloads/2004/DCLP_notes.pdf -- Eric Niebler Boost Consulting www.boost-consulting.com