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Re: [PATCH] Get rid of awkward precision for bitsize types

From: Eric Botcazou <ebotcazou at adacore dot com>
To: Richard Guenther <richard dot guenther at gmail dot com>
Cc: gcc-patches at gcc dot gnu dot org
Date: Mon, 6 Apr 2009 20:08:39 +0200
Subject: Re: [PATCH] Get rid of awkward precision for bitsize types
References: <200904061224.16916.ebotcazou@adacore.com> <84fc9c000904060324y467489dcq417d282f8c5dbcf7@mail.gmail.com>

> I know that sizetypes "do not overflow" (err, well ...) - but do you
> realize that doing this makes overflow behavior different between
> a computation in sizetype and one in bitsizetype with bit
> quantities?

Note that there is a precedent:

2006-11-18  John David Anglin  <dave.anglin@nrc-cnrc.gc.ca>

	PR fortran/27885
	PR middle-end/28176
	* stor-layout.c (set_sizetype): Limit precision of *bitsizetypes types
	to MAX_FIXED_MODE_SIZE.

After it, bitsizetypes overflow before sizetypes on x86-64 and this doesn't 
seem to have any practical consequences.

-- 
Eric Botcazou

Follow-Ups:
- Re: [PATCH] Get rid of awkward precision for bitsize types
  - From: Richard Guenther

References:
- [PATCH] Get rid of awkward precision for bitsize types
  - From: Eric Botcazou
- Re: [PATCH] Get rid of awkward precision for bitsize types
  - From: Richard Guenther

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