Messages in this thread |  | | Date | Thu, 11 Oct 2001 18:41:32 -0400 | Subject | Re: [PATCH] 2.4.10-ac11 parport_pc.c bugfix | From | (bill davidsen) |
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In article <1002808349.10317.7.camel@thanatos> you write: | I guess the question is: Which way is more portable? Is | "(unsigned long)-1" liable to turn out as something other than | ~0U? | | If your way of expressing it is more portable then we should | make the change ... BOTH in pnp_bios.c and in parport_pc.c . | | Opinions?
Does this address any bug present without the cast? If the expression left of == is unsigned long, ~0U will work, as will (unsigned)~0. But more to the point, do you mean "minus one" or "all ones" here? While Linux does not currently run on any machine which is not 2's complement, I think if you want all ones you should use (unsigned long)~0 as most portable.
Yes, I have programmed 1's complement machines :-(
-- bill davidsen <davidsen@tmr.com> "If I were a diplomat, in the best case I'd go hungry. In the worst case, people would die." -- Robert Lipe - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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