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Re: Rationale for some rules in style guide



Am Wed, Apr 12, 2023 at 07:53:23AM +0930 schrieb Brett Lymn:
> On Tue, Apr 11, 2023 at 08:30:19PM +0200, Roland Illig wrote:
> > 
> > The style guide says:
> > > When declaring variables in functions declare them sorted by size
> > 
> > What is the purpose of this rule, and is it still useful? I'd rather see
> > the variables grouped by topic. If that rule's purpose is to help some
> > ancient compiler lay out the variables efficiently, I don't see a point
> > in keeping that rule, as modern compilers are advanced enough.
> > 
> 
> To save stack space?  If you mix up the sizes of the variables then
> there would be wasted memory due to alignment constraints for accessing
> a certain sized variable.  Those constraints are processor not compiler
> artifacts.  Unless compilers are smart enough to reorder the variables
> to pack them efficiently in memory then it is still a good idea to do
> this

Which compiler from this century doesn't allocate stack space
independent from the source order?

Joerg


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