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