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From: =?ISO-8859-1?Q?Markus_Sch=F6pflin?= <no.spam@spam.spam>
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Subject: Re: Simple Warnings Needs
Date: Thu, 24 Feb 2011 09:26:35 +0100
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Date: 2011-02-24T09:26:35+01:00
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Am 23.02.2011 22:55, schrieb Martin:

[...]

> I seem to remember an article by Dewar explaining why constants can
> rarely be optimized but I can't put my finger on it at the moment...

There has been a GOTW article about this. It of course discusses C++, but 
most statements are also valid for other languages. See 
http://www.gotw.ca/gotw/081.htm.

To quote from it's summary at the end:

<quote>
It's a common belief that const-correctness helps compilers generate 
tighter code. Const is indeed a Good Thing, but the point of this issue of 
GotW is that const is mainly for humans, rather than for compilers and 
optimizers. When it comes to writing safe code, const is a great tool that 
lets programmers write safer code with compiler checking and enforcement. 
Even when it comes to optimization, const is still principally useful as a 
tool that lets human class designers better implement handcrafted 
optimizations, and less so as a tag for omniscient compilers to 
automatically generate better code.
</quote>

Markus