Re: [PATCH 2/2] document ISL requirement for GCC installation

Re: [PATCH 2/2] document ISL requirement for GCC installation

[Sebastian Pop]

On Fri, Aug 12, 2011 at 12:50, Jack Howarth <howarth@bromo.med.uc.edu> wrote:
> On Fri, Aug 12, 2011 at 07:35:24PM +0200, Sven Verdoolaege wrote:
>> On Fri, Aug 12, 2011 at 05:02:18PM +0000, Joseph S. Myers wrote:
>> > On Fri, 12 Aug 2011, Sebastian Pop wrote:
>> > > +@item Integer Set Library (ISL) version 0.08
>> > > +
>> > > +Necessary to build GCC with the Graphite loop optimizations.
>> > > +It can be downloaded from @uref{http://www.kotnet.org/~skimo/isl/}.
>> >
>> > So have things changed relative to what was said in
>> > <http://gcc.gnu.org/ml/gcc-patches/2010-08/msg00873.html> about ISL being
>> > included in CLooG-ISL?
>>
>> isl is still included in CLooG, but Sebastian now wants to use isl
>> itself in graphite.
>>
>> skimo
>
>   Will graphite be totally converted to isl such that ppl can be deprecated
> in time for the gcc 4.7 release?
>                  Jack

Yes, having GCC only depend on ISL and CLooG-ISL (and not depend
anymore on PPL) is our plan for 4.7.

The rationale behind this is that with PPL it would be very difficult to fix
bugs due to wrap around unsigned types, like this one:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47594
With ISL it is possible to represent the wrapping types and fix this bug.

Sebastian