[U-Boot] [PATCH] arm: prevent using movt/movw address loads

Wolfgang Denk wd at denx.de
Tue Sep 17 12:19:32 CEST 2013


Dear TigerLiu at viatech.com.cn,

In message <FE7ADED5C2218B4786C09CD97DC4C49FA88EDF at exchbj02.viatech.com.bj> you wrote:
>
> >May I ask why you want to use other optimization levels?  Do you just
> >hope that your code may run faster, or do you have actual proof (i. e.
> >measurements) that this is the case?  It would be interesting if you
> >could share any such measured results.
> 
> Not for running faster.
> I just think:
> If turn off compiler optimization, some bugs would be analysed easily.

Hm... that does not match my experience.  A pretty large percentage of
actual bugs is of Heisenbug nature.  Changin the buil environment will
create a completely different image with different behaviour - you may
be lucky, but too often the changes actually side-track you from the
actual issues.

Best regards,

Wolfgang Denk

-- 
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