From: Wolfgang Denk <wd@denx.de>
Date: Thu, 20 Aug 2009 11:28:29 +0200
Subject: [U-Boot] [PATCH "mkimage" branch] tools/mkimage: fix compiler
	warnings, use "const"
In-Reply-To: <73173D32E9439E4ABB5151606C3E19E202E3915996@SC-VEXCH1.marvell.com>
References: <73173D32E9439E4ABB5151606C3E19E202E3915996@SC-VEXCH1.marvell.com>
Message-ID: <20090820092829.120A8833DBD2@gemini.denx.de>
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To: u-boot@lists.denx.de

Dear Prafulla,

In message <73173D32E9439E4ABB5151606C3E19E202E3915996@SC-VEXCH1.marvell.com> you wrote:
> 
> > This fixes some compiler warnings:
> > tools/default_image.c:141: warning: initialization from 
> > incompatible pointer type
> > tools/fit_image.c:202: warning: initialization from 
> > incompatible pointer type
> > and changes to code to use "const" attributes in a few places where
> > it's appropriate.
>
> 99% of the changes in this patch is to add const attributes.

Yes, indeed.

> Can you pls explain here- how useful it is to add const.

Well, adding "const" where appropriate is definitely a good thing, as
it const augments data-hiding and encapsulation and allows the
compiler to check for (and prevent!) unintended modification of data
structures, i. e. for programming errors. Also, it helps the compiler
for better optimization.

> Or do it make more sense just to fix the warnings in respective functions?
> I have posted a patch for the same

I did not see any patch form you addressing these warnings?

My "const"-adding patch was the more or less direct result of getting
rid of the warnings without using additional type casts.

I think using const is a good thing. I am aware that it sometimes
becomes painful, and some consider it a waste of time.

Best regards,

Wolfgang Denk

-- 
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Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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