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From: Mok-Kong Shen <mok-kong DOT shen AT t-online DOT de>
Newsgroups: comp.os.msdos.djgpp
Subject: bit shifting problem
Date: Wed, 09 Feb 2005 23:07:02 +0100
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Sorry for posing yet another, possibly also newbie, problem.
In the following code I expected the values of k and n to be
both 0, since shifting 32 bits for a 32-bit word effectively
clears it. But the values printed were 42800637 and 1369620384.
The compiler did give the warning message "right shift count
 >= width of type". But shifting 32 bits (not exceeding the
word size) is allowed or is it forbidden by the C standard?
Thanks.

M. K. Shen
--------------------------------

#include <stdio.h>
int main()
{ int i,j,k,n;
   unsigned long w;
   w=42800637;
   i=w>>31;
   j=i>>1;
   k=w>>32;
   n=(w<<5)>>32;
   printf("%lu %d %d %d %d\n",w,i,j,k,n);
   return 0;
}