Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!apple!mips!batman!rudy
From: rudy@mips.COM (Rudy Wang)
Newsgroups: comp.sys.mips
Subject: Re: RISC/C V2.0 bug
Message-ID: <37026@mips.mips.COM>
Date: 14 Mar 90 22:01:31 GMT
References: <2597@cs-spool.calgary.UUCP>
Sender: news@mips.COM
Reply-To: rudy@mips.COM (Rudy Wang)
Organization: MIPS Computer Systems, Sunnyvale, CA
Lines: 52

In article <2597@cs-spool.calgary.UUCP> cliff@.UCalgary.CA () writes:
>Hi Netters :
>
>  I'd like to report a bug in the RISC/C 2.0 compiler.  Given the source
>  code below, and the contents of the data file "5577".  This program
>  kicks out 12 zeros.  If all instances of "short int" are changed to "int",
>  the bug goes away.
>
>  I suspect that in the "short int" case, that only the top 16 bits of
>  an "int" are actually being placed into "i"...
>
>  Any thoughts/comments would be appreciated.  I'm running on RS-2030's
>  using RISC/C V2.0 under RISC/os 4.10.
>
>-------------------------------------------------------------------------------
>#include <stdio.h>
>int j;
>main()
>{
>	int rfd;
>	FILE *fp;
>	short int i;
>	fp = fopen("5577","r");
>	for(j=0;j<12;j++)
>	{
>		fscanf(fp,"%4d ",(short int *)&i);
                           ^^^
>		printf("%d ",(short int)i);
                        ^^
>	}
>	close(fp);
>}
>-------------------------------------------------------------------------------
> and here's the input file:
>
> 1747 1754 1767 1775 1804 1784 1782 1775 1751 1712
> 1674 1624 1589 1550 1505 1476 1450 1415 1364 1351
	....
>-------------------------------------------------------------------------------
>Cliff Marcellus                UUCP     : {any backbone}!calgary!ssg-vax-a!cliff
>Dept of Physics and Astronomy  DOMAIN   : cliff@ssg-vax-a.phys.UCalgary.CA
>The University of Calgary      SPAN     : CANCAL::CLIFF                 
>OPINIONS WITHIN ARE MY OWN AND DO NOT REFLECT THOSE OF THE UNIVERSITY OF CALGARY


Try using "%4hd" and "%hd", you'll like it.  To get more info on the scanf
format string, do "man fscanf" and go through it carefully.
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