From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <003c01c10ddb$248d6650$3cf7c6d4@SOMA>
From: "Boyd Roberts" <boyd@fr.inter.net>
To: <9fans@cse.psu.edu>
References: <200107140326.f6E3Q7j03750@ducky.net> <3B512D07.97B5B213@null.net>
Subject: Re: [9fans] another compiler bug (another try to send this coherently)
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Date: Mon, 16 Jul 2001 11:38:59 +0200
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>         printf("%d %d\n", tab[0] << 24 >> 31, x << 24 >> 31);

i really don't understand what the problem is here.  it's
very simple (not that i have a copy of k&r 2 or the
standard with me).

shifting stuff:

    - verify what you're shifting [signed/unsigned]
    - if it's signed, watch out for setting the sign bit
    - shifts that cause over/under-flow may ruin your
      whole day
    - when in doubt, _read_ the doc

if you'd like to see some bit mangling code, read:

    http://www.planete.net/~boyd/code/des.msg