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From: Mike Haertel <mike@ducky.net>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] another compiler bug (another try to send this coherently)
Date: Mon, 16 Jul 2001 11:34:55 -0700	[thread overview]
Message-ID: <200107161834.f6GIYtl10556@ducky.net> (raw)
In-Reply-To: <3B512D07.97B5B213@null.net>

>Mike Haertel wrote:
>> On a conforming implementation with 32-bit ints, this
>> program should print "-1 -1".
>>         static unsigned char tab[1] = { 0x80 };
>>         static int x = 0x80;
>>         printf("%d %d\n", tab[0] << 24 >> 31, x << 24 >> 31);
>
>How do you figure that?  The promoted tab[0] (signed int) or x
>left-shifted 24 places sets the sign bit, and right-shifting a
>negative value is implementation-defined.

Sorry, my mistake.

Whatever it prints, it should print the same number twice,
not two different values.


  parent reply	other threads:[~2001-07-16 18:34 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2001-07-14  3:26 Mike Haertel
2001-07-16  9:05 ` Douglas A. Gwyn
2001-07-16  9:38   ` Boyd Roberts
2001-07-16 18:34   ` Mike Haertel [this message]
2001-07-16 18:52     ` Boyd Roberts
2001-07-16 19:21       ` Mike Haertel
2001-07-16 19:47         ` Boyd Roberts
2001-07-17 15:16         ` Douglas A. Gwyn
2001-07-16 11:13 rog
2001-07-16 12:51 ` Boyd Roberts
2001-07-16 13:41   ` Boyd Roberts
2001-07-16 13:44   ` Boyd Roberts
2001-07-17 15:51 forsyth
2001-07-18  8:43 ` Douglas A. Gwyn

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