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Subject: Re: [PATCH] Fortran: handle explicit-shape specs with constant bounds
 [PR105954]
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To: Harald Anlauf <anlauf@gmx.de>, fortran <fortran@gcc.gnu.org>,
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References: <trinity-ea5cca86-9a4a-47f5-889c-a862eb562044-1655752252939@3c-app-gmx-bap34>
From: Thomas Koenig <tkoenig@netcologne.de>
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Hello Harald,

> after simplification of constant bound expressions of an explicit
> shape spec of an array, we need to ensure that we never obtain
> negative extents.  In some cases this did happen, and we ICEd
> as we hit an assert that this should never happen...
> 
> The original testcase by Gerhard exhibited this for sizeof()
> of a derived type with an array component, but the issue is
> more fundamental and affects other intrinsics during
> simplification.
> 
> A straightforward solution "fixes up" the upper bound in the
> shape spec when it is known to be below lower bounds minus one.
> 
> Regtested on x86_64-pc-linux-gnu.  OK for mainline?

OK.  Thanks for the patch!

Regards

	Thomas