bug? gcc/graphite-poly.h:398:43: error: 'isl_constraint' has not been declared

Jonathan Wakely jwakely.gcc@gmail.com
Fri Oct 2 15:54:00 GMT 2015

On 2 October 2015 at 13:57, dclarke@blastwave.org <dclarke@blastwave.org> wrote:
>> >
>> > It has been a while since I tried to bootstrap gcc and with the
>> > latest
>> > production release 5.2.0 and I see on the "Prerequisites for GCC"
>> > page
>> > that "ISL Library version 0.15, 0.14, 0.13, or 0.12.2" is required
>> > as
>> > per https://gcc.gnu.org/install/prerequisites.html
>> It's not required, because it's only used for the optional Graphite
>> optimisations.
> Thank you for the reply.
> My issue here is that it is on the "Prerequisites" page as a clearly
> needed piece and not merely optional. It should be marked as an optional
> piece and not a "Prerequisite".

It says "Necessary to build GCC with the Graphite loop optimizations."

Compare it to the previous items which say "Necessary to build GCC."

The difference is not accidental (although maybe too subtle).

The Graphite loop optimizations are optional, so if you don't need to
build GCC with them, you don't need ISL.

>> > Wondering if isl 0.15 is really ready to go or should I use a
>> > previous
>> > version or can I remove the isl bits entirely ?
>> You don't need ISL to build GCC and can remove it entirely.
> Will do. I have never seen the cloog or isl bit compile on Solaris.
> Ever. Once. In years. Ever. So it was very frustrating to see the ISL
> bits as a "required" and "needed" piece.

They have never been needed, and I've said so previously in an email
you replied to:

> No worries .. I'll give it a try without ISL and then try again later
> with bits from ./contrib/download_prerequisites as you suggest.

Which is suggested on the https://gcc.gnu.org/wiki/InstallingGCC page,
linked to from the mail you replied to, saying you'd read it :-)  I've
just updated that page to make it explicit that ISL is only needed for
the optional Graphite optimizations.

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