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* [PATCH] Update changes.html about -Wno-aggressive-loop-optimizations
@ 2013-03-22 10:28 Jakub Jelinek
  2013-03-22 10:34 ` Richard Biener
  0 siblings, 1 reply; 2+ messages in thread
From: Jakub Jelinek @ 2013-03-22 10:28 UTC (permalink / raw)
  To: Richard Biener; +Cc: gcc-patches

Hi!

This new warning switch hasn't been mentioned in changes.html, the following
patch fixes that.  Is this ok, or do you have better wording?

--- htdocs/gcc-4.8/changes.html	14 Mar 2013 01:13:56 -0000	1.108
+++ htdocs/gcc-4.8/changes.html	22 Mar 2013 10:22:37 -0000
@@ -32,7 +32,12 @@ the number of iterations of loops using 
 standards.  This may cause non-conforming programs to no longer work as
 expected, such as SPEC CPU 2006 464.h264ref and 416.gamess.  A new
 option, <code>-fno-aggressive-loop-optimizations</code>, was added
-to disable this aggressive analysis.</p>
+to disable this aggressive analysis.  In some loops that have known
+constant number of iterations, but undefined behavior is known to occur
+in the loop before reaching or during the last iteration, GCC will warn
+about the undefined behavior in the loop instead of deriving lower upper
+bound of the number of iterations for the loop.  The warning
+can be disabled with <code>-Wno-aggressive-loop-optimizations</code>.</p>
 
 <p>On ARM, a bug has been fixed in GCC's implementation of the AAPCS
 rules for the layout of vectors that could lead to wrong code being

	Jakub

^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: [PATCH] Update changes.html about -Wno-aggressive-loop-optimizations
  2013-03-22 10:28 [PATCH] Update changes.html about -Wno-aggressive-loop-optimizations Jakub Jelinek
@ 2013-03-22 10:34 ` Richard Biener
  0 siblings, 0 replies; 2+ messages in thread
From: Richard Biener @ 2013-03-22 10:34 UTC (permalink / raw)
  To: Jakub Jelinek; +Cc: gcc-patches

On Fri, 22 Mar 2013, Jakub Jelinek wrote:

> Hi!
> 
> This new warning switch hasn't been mentioned in changes.html, the following
> patch fixes that.  Is this ok, or do you have better wording?

No, looks ok to me.

Richard.

> --- htdocs/gcc-4.8/changes.html	14 Mar 2013 01:13:56 -0000	1.108
> +++ htdocs/gcc-4.8/changes.html	22 Mar 2013 10:22:37 -0000
> @@ -32,7 +32,12 @@ the number of iterations of loops using 
>  standards.  This may cause non-conforming programs to no longer work as
>  expected, such as SPEC CPU 2006 464.h264ref and 416.gamess.  A new
>  option, <code>-fno-aggressive-loop-optimizations</code>, was added
> -to disable this aggressive analysis.</p>
> +to disable this aggressive analysis.  In some loops that have known
> +constant number of iterations, but undefined behavior is known to occur
> +in the loop before reaching or during the last iteration, GCC will warn
> +about the undefined behavior in the loop instead of deriving lower upper
> +bound of the number of iterations for the loop.  The warning
> +can be disabled with <code>-Wno-aggressive-loop-optimizations</code>.</p>
>  
>  <p>On ARM, a bug has been fixed in GCC's implementation of the AAPCS
>  rules for the layout of vectors that could lead to wrong code being
> 
> 	Jakub
> 
> 

-- 
Richard Biener <rguenther@suse.de>
SUSE / SUSE Labs
SUSE LINUX Products GmbH - Nuernberg - AG Nuernberg - HRB 16746
GF: Jeff Hawn, Jennifer Guild, Felix Imend

^ permalink raw reply	[flat|nested] 2+ messages in thread

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