RE: [boost] Re: [Review] Named parameters library

From: Stefan Seefeld (sseefeld_at_[hidden])
Date: 2004-11-18 10:08:35

> From: Doug Gregor [mailto:dgregor_at_[hidden]]

> Since I've been researching in this area for several years...
> 
> Dave is correct: no compiler out there is going to optimize this, 
> because the side effects are killer. It is possible to analyze that 
> behavior and perform the optimization Thorsten is describing, but
> 
> 	(1) There are better ways than looking at it from the memory 
> subsystem/pointer magic angle
> 	(2) This is very much an open research area; don't 
> expect this from a 
> research compiler for at least 2 years.
> 	(3) This is very much an open research area; don't 
> expect this from a 
> commercial compiler for at least 10 years.
> 
> Copy elision and the RVO are all we have. We can't rely on anything 
> more than that.

out of curiosity: what about the LD_PRELOAD trick that's used on
ELF systems to replace symbols at startup ? It's notably used by
some tools to swap in special versions of operator new/delete to
analyze memory management without the need to recompile anything.

Is there any way for a compiler to know that some calls can be fully
evaluated at compile-time ?

Thanks,
                Stefan