From: Ian Lance Taylor <ian@wasabisystems.com>
To: Christian Groessler <cpg@aladdin.de>
Cc: GCC List <gcc@gcc.gnu.org>
Subject: Re: signed/unsigned right shift
Date: Sun, 14 Mar 2004 18:23:00 -0000 [thread overview]
Message-ID: <m3znajjnjd.fsf@gossamer.airs.com> (raw)
In-Reply-To: <87vfl7s3lf.fsf@aladdin.de>
Christian Groessler <cpg@aladdin.de> writes:
> >Correct, the multiplication is done as signed int. And it is
> >implementation
> >defined whether right shift of a negative signed int does sign fill or
> >not.
> >So both compilers are right; it is only your code that's wrong.
> >
> >C89 references: 3.3.7, 3.2.1.5, 3.2.1.1.
>
> Hmm, unfortunately I don't have the c89 standard document. Can
> somebody point me to the equvalent sections in c99?
Usual arithmetic conversions performed on operands of multiplication:
6.5.5.
Usual arithmetic conversions: 6.3.1.8. Note in particular "the
integer promotions are performed on both operands."
Integer promotions: 6.3.1.1.
Right shift of signed negative value implementation defined: 6.5.7.
Ian
next prev parent reply other threads:[~2004-03-14 18:23 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-03-14 18:09 Christian Groessler
2004-03-14 18:23 ` Ian Lance Taylor [this message]
-- strict thread matches above, loose matches on Subject: below --
2004-03-15 22:24 Christian Groessler
2004-03-15 22:02 Christian Groessler
2004-03-15 22:14 ` Andreas Schwab
2004-03-15 22:18 ` Andreas Schwab
2004-03-15 22:17 ` Ian Lance Taylor
2004-03-12 21:25 Christian Groessler
2004-03-12 22:24 ` Andreas Schwab
2004-03-12 22:37 ` Dale Johannesen
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