Re: [PATCH] shm: Remove silly double assignment

[Ingo Molnar <mingo@elte.hu>]

* Neil Horman <nhorman@tuxdriver.com> wrote:

> > Not silly, really.  Look:
> > 
> > 	err = -ENOMEM;
> > 	if (expr1)
> > 		goto out;
> > 
> > 	err = -ENOMEM;
> > 	if (expr2)
> > 		goto out;
> > 
> > each of these two units is a separate, self-contained clause.  
> > Removing the second assignment to `err' breaks that separation and 
> > will make one clause undesirably dependent upon the other.
>
> yes, I see that keeping the second assignment lets you insert code in 
> the middle without having up to update afterwards.  I just don't think 
> the redundant assignment is worth keeping just for that purpose.

cleanups is all about having familar, robust, predictable, 
self-contained patterns of code that are easy to recognize, easy to 
review and easy to keep working well.

In this case we've got an admittedly boundary case: removing the 
technically redundant piece of code, while a valid cleanup at first 
sight, makes the code less robust against future changes.

	Ingo