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Re: bit_size_type - a data type?

From: Florian Weimer <fw at deneb dot enyo dot de>
To: kenner at vlsi1 dot ultra dot nyu dot edu (Richard Kenner)
Cc: richard dot guenther at gmail dot com, gcc at gcc dot gnu dot org, shafitvm at gmail dot com
Date: Tue, 13 May 2008 10:39:13 +0200
Subject: Re: bit_size_type - a data type?
References: <ba0bd44d0805120258r3df0233ck4998aa1b91d1fbbd@mail.gmail.com> <84fc9c000805120311y2d474049od36ff068ef66d268@mail.gmail.com> <10805121126.AA09176@vlsi1.ultra.nyu.edu>

* Richard Kenner:

>> bitsizetype is a type that can hold any values of sizetype *
>> BITS_PER_UNIT so we can safely do bit-size calculations without overflow.
>> This type shouldn't end up used in code though.
>
> Unfortunately, it does, though not in C.  Ada's 'Size attribute returns
> the size in bits, so the proper type for that computations is bitsizetype,
> though many computations end up being constant-folded.

Ada used a 32-bit signed integer type in this case, limiting object size
to 2**31 bits.  Is this no longer the case?

Follow-Ups:
- Re: bit_size_type - a data type?
  - From: Richard Kenner

References:
- bit_size_type - a data type?
  - From: Mohamed Shafi
- Re: bit_size_type - a data type?
  - From: Richard Guenther
- Re: bit_size_type - a data type?
  - From: Richard Kenner

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