[boost] Singleton (aligned_storage)

From: Jason Hise (chaos_at_[hidden])
Date: 2005-01-11 23:16:50

Noah Stein wrote:

>Your Create() function in AllocateUsingNew isn't guaranteed to work for all classes.  The type of the singleton class might have alignment restrictions.  char has no alignment restrictions; therefore, the program may crash when
>trying to initialize the singleton.  I believe boost::aligned_storage is your friend in this situation.
>
I looked into aligned storage, and discovered that it is interwoven deep 
into boost, and includes many dependencies.  Although I think it would 
be great if this library became a part of boost, I don't want to make it 
dependent upon becoming a part of boost just to solve the aligned 
storage issue.

Perhaps I could add extension headers, which would contain the extra 
policies that require specific platforms or libraries.  Then my 
singleton header would only include them if a corresponding tag 
(BOOST_AVAILABLE) has been defined or something of that nature.  Of 
course, such action would be a last resort... if aligned_storage is a 
simple enough device, I would prefer to just inline it as an 
implementation detail of the static allocation policy.  How dependent 
upon the compiler being used is the implementation of aligned_storage?  
Is implementing a bare-bones version myself feasible?

-Jason