From:	mrh99 AT uswest DOT net (Matthew Haley)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: What's this? A bug?
Organization:	Home
Message-ID:	<37fb7201.1121707@news.uswest.net>
References:	<MO8+3UJ05Q5a092yn AT jagor DOT srce DOT hr>
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Date:	Wed, 06 Oct 1999 16:02:43 GMT
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Hi Viktor Bresan ,

An int is only guaranteed to be *at least* 16-bits. With a real
compiler such as you have now, an int is 32-bits.

 On 6 Oct 1999 17:10:51 +0200,
 <<Viktor Bresan>> wrote:

>Here is the code which counts the number of nonzero bits in int value.
>It works fine until you enter negativ value, e.g. when i enter value -1
>it counts 32 nonzero bits (although we all know that int has only 16 bits)!?
>The same code compiled under the BC++ 3.1 acts normal (under 16 bits counted
>for each negative value).
>
>Am i doing something wrong? What happends here?
>Thanx!
>
>--------------------------------- cut - cut ---------------------------------
>#include <conio.h>
>#include <stdio.h>
>
>
>char CntBits(int val)
> { char ret_val;
>   int maska;
>
>   ret_val = 0;
>   maska = 1;
>   while(maska)
>     {
>       if(val & maska)
>           ret_val++;
>
>       maska <<= 1;
>     }
>
>   return (ret_val);
> }
>
>int main(/*int argc, char *argv[]*/)
> { char CntBits(int);
>   int val;
>
>   clrscr();
>   printf("Enter int value: ");
>   scanf("%i",&val);
>
>   printf("%i nonzero bit(s)!",CntBits(val));
>
>   return (0);
> }
>
>----------------------------------- cut - cut -------------------------------
>
>
>-- 
>Viktor Bresan, student of electronics at FESB Split, Croatia
>http://public.srce.hr/~vbresan/

===================================
Matthew Haley
mrh99 AT uswest DOT net
http://www.users.uswest.net/~mrh99
===================================

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