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From: bc@cyb-eng.UUCP (Bill Crews)
Newsgroups: net.lang.c,net.micro,net.micro.pc
Subject: Re: weird C behavior
Message-ID: <796@cyb-eng.UUCP>
Date: Wed, 2-Apr-86 19:30:40 EST
Article-I.D.: cyb-eng.796
Posted: Wed Apr  2 19:30:40 1986
Date-Received: Sat, 5-Apr-86 07:03:35 EST
References: <557@utastro.UUCP>
Organization: Cyb Systems, Austin, TX
Lines: 32
Xref: linus net.lang.c:7745 net.micro:12960 net.micro.pc:7332

> /* weird.c - demonstrate weird C behavior */
> /* Reference: Kernighan and Ritchie pp. 40-41 */
. . .
> #define BIG 36864
> 
> main()
> {
> int i;
> 
> i = BIG;
> if(i == BIG)
>     printf("Equality found: i = %d, BIG = %d\n", i, BIG);
> else
>     printf("Equality NOT found: i = %d, BIG = %d\n", i, BIG);
> }
> 
> Equality NOT found: i = -28672, BIG = -28672
> 
> -----------------------------------------------------------------------
> Ed Nather
> Astronomy Dept, U of Texas @ Austin

It seems to me that your compiler has done the right thing.  Since 36864
cannot be represented as an int on your machine, it generated a positive
long rather than a negative int.  When i is extended to a long, the sign
bit is extended, so the comparison fails, as it should.  The only reason
you got -28672 for BIG instead of nulls is because your machine has backwards
byte order.
-- 
	- bc -

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