From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo Krabbe <ikrabbe@earthling.net>
To: Alexandre Oliva <aoliva@redhat.com>
Cc: David Berthelot <davidb@Magma-DA.COM>, Ben Kohlen <bckohlen@yahoo.com>, <gcc-help@gcc.gnu.org>
Subject: Re: bug?
Date: Mon, 18 Jun 2001 23:58:00 -0000
Message-id: <Pine.LNX.4.33.0106190902450.15293-100000@flathead.burg.de>
References: <or8zipt36o.fsf@guarana.lsd.ic.unicamp.br>
X-SW-Source: 2001-06/msg00137.html

On 19 Jun 2001, Alexandre Oliva wrote:

> On Jun 18, 2001, Ingo Krabbe <ikrabbe@earthling.net> wrote:
>
> > Hmm, I see that we can also do
> > x & (~(x^x)>>n) which is really easier :-)
>
> This is only well-defined if x's type is unsigned.  The behavior of
> right-shifting negative values is undefined (or unspecified?)
>
That's a kind of why I used ~(~(x^x)<<(sizeof(x)*8-n)).

CU INGO