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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: Sat, 11 Dec 2021 17:53:20 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D102043

--- Comment #28 from Mikael Morin <mikael at gcc dot gnu.org> ---
I=E2=80=99m reading the previous comments again:

(In reply to Richard Biener from comment #10)
> So to clarify the ARRAY_REF constraints - there is currently no way to
> construct a valid ARRAY_REF where an index does an access to memory before
> the supplied
> base object.  TREE_OPERAND (array_ref, 0) needs to always be the array,
> it's address needs to be the address of the _first_ element.  For negative
> strides gfortran seems to construct the array object in a way so its
> address points to the _last_ element of the array.  That's not supported.
>=20
does that means that clearing the lower bound information from the type as I
suggested in my last comment would not work?=