Re: [boost] Is there interest in an alternative to the Singleton anti-pattern?

Subject: Re: [boost] Is there interest in an alternative to the Singleton anti-pattern?
From: Ben Robinson (icaretaker_at_[hidden])
Date: 2011-06-28 03:39:40

>
> On 24 June 2011 02:06, Ben Robinson <icaretaker_at_[hidden]> wrote:
>
> > If you choose the default policy of single_threaded, there is no
> > thread safety, but there is also no overhead in using a mutex and using
> a
> > volatile pointer.
> >
>
> Volatile in C++ doesn't really help with threading...  Check out <
> http://software.intel.com/en-us/blogs/2007/11/30/volatile
> -almost-useless-for-multi-threaded-programming/>
> for one of many articles on the subject.
> --
>  Nevin ":-)" Liber  <mailto:nevin_at_[hidden]>  [phone]

Nevin,

I greatly appreciate the input you have provided.  I retract my original
response, as I now better understand why volatile does not add any value to
Singularity.  Singularity is already acquiring a mutex object, before
accessing the shared instance pointer, and that mutex acquisition is already
providing memory fencing.

I have simplified the implementation of Singularity and the latest version
is available at: https://github.com/icaretaker/Singularity.  Any additional
input would be appreciated.

Thank you,

Ben Robinson, Ph.D.