Update changes.html about -Wno-aggressive-loop-optimizations

Submitted by Jakub Jelinek on March 22, 2013, 10:26 a.m.

Details

Message ID 20130322102627.GX12913@tucnak.redhat.com
State New
Headers show

Commit Message

Jakub Jelinek March 22, 2013, 10:26 a.m.
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?


	Jakub

Comments

Richard Guenther March 22, 2013, 10:33 a.m.
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
> 
>

Patch hide | download patch | download mbox

--- 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