Re: [boost] [thread] thread-safe static local

Subject: Re: [boost] [thread] thread-safe static local
From: Phil Endecott (spam_from_boost_dev_at_[hidden])
Date: 2009-03-03 11:37:54

Oliver Kowalke wrote:
> I need a function 'get_default_X()' returning a reference to a singleton in a multithreaded env.
> I choosed Scott Meyers singleton pattern (static local) together with boost::call_once().
> My this be a reasonable, threadsafe implementation?

Hi Oliver,

I wasn't able to see your implementation because the mailing list 
server still creates these broken links:

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It would be great if someone who knows how the mailing list works could 
investigate this.  In the meantime, perhaps you could put the files 
online somewhere?

As you may know, gcc creates local statics that are thread safe by 
default.  So I have a macro something like this:

#if __GCC__
#define THREAD_SAFE_STATIC(TYPE,NAME) static TYPE NAME;
#else
#define THREAD_SAFE_STATIC(TYPE,NAME) #error FIXME
#endif

If your code can be used in the #else case, that would be great.  I 
think it's important to use the gcc feature when available as the 
alternative will probably involve an unnecessary extra layer of locking.

Phil.