From: David Given <dg@cowlark.com>
To: linux-sparse@vger.kernel.org
Subject: Re: [RFC] potential DR in handling of signed int and unholy mess in our and gcc implementations
Date: Thu, 19 Mar 2009 02:33:00 +0000 [thread overview]
Message-ID: <49C1AEDC.9030809@cowlark.com> (raw)
In-Reply-To: <20090319013358.GZ28946@ZenIV.linux.org.uk>
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Al Viro wrote:
[...]
> I'll probably go for gcc-like behaviour in sparse for now, unless somebody
> sees a good reason not to. At least that one is consistent and doesn't
> bring the shitloads of fun questions about behaviour of arithmetic conversions,
> etc.
>
> Comments?
All I can really say to that is: ew.
I like bitfields and use them frequently, particularly for flags and
packing several small fields into a small space; luckily I've already
been pretty anally retentive about declaring them explicitly as 'signed'
or 'unsigned'.
- From the compiler perspective, Principle of Least Surprise would suggest
doing the consistent thing, which as you say is gcc-like. OTOH from the
linter perspective I'd be *strongly* in favour of a warning if sparse
sees a problematic declaration. Bitfields are an area where signedness
suddenly becomes really important. (int i : 1, anyone?)
Are you submitting a bug report to the standards people?
- --
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next prev parent reply other threads:[~2009-03-19 2:55 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-03-19 1:33 [RFC] potential DR in handling of signed int and unholy mess in our and gcc implementations Al Viro
2009-03-19 2:33 ` David Given [this message]
2009-03-19 12:10 ` Derek M Jones
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