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From: "mikael at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug fortran/102043] Wrong array types used for negative stride
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Date: Fri, 19 Nov 2021 18:31:27 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D102043

--- Comment #23 from Mikael Morin <mikael at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #21)
> (In reply to Bernhard Reutner-Fischer from comment #17)
> > Do we want to address arrays always at position 0 (maybe to help graphi=
te ?)
>=20
> Helping graphite (and other loop optimizers) would be to not lower
> multi-dimensional accesses to a single dimension (I think that's what
> Sandras patches try to do).=20

Or maybe graphite can be taught to handle flattened array access?

Anyway, does the middle-end support out-of-order array access?
Namely for an array arr(4, 5, 6), arr(:, 1, :) is an array of size (4, 6).
Does the middle-end type system support this?

In any case, it=E2=80=99s not for gcc 12.

> The lower bound doesn't really matter here and
> is well-handled by all code.

Well, unless the lower bound is negative. ;-)=