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From: shodsdon@elrond.CalComp.COM (Steve V. Hodsdon)
Newsgroups: comp.sys.dec
Subject: Re: Compiler Bug
Summary: Fails on a MIPS box also...
Message-ID: <2856@elrond.CalComp.COM>
Date: 27 Jul 90 15:29:11 GMT
References: <3152@rwthinf.UUCP>
Distribution: comp
Organization: Calcomp, A Lockheed Company, Hudson, NH, USA
Lines: 59

In article <3152@rwthinf.UUCP>, davids@bduxpe (Peter Davids) writes:
> 
> We have DEC 3100 Workstation with Ultrix 3.1 and UWS 2.1 running.
> The following little (and correct!?) C-program gives different results,
> depending on the optimizer options.
> The programm look a bit like the own posted some time ago...
> 
> 
> ====cut here==============================
> char *   malloc();
> 
> main()
> {
>   char *   ba;
>   int i=3;
>   printf("%d\n", i*(-6) );
>   ba = malloc (100);
>   printf("%d\n", i*(-6) );
> }
> 
> I will be happy about any idea or answer (other bugs would be also
> very interesting)

I am running a MIPS box with the R2600 CPU card (R2000 processor).

Here is the output: (using uMIPS 2.0)

[shodsdon@(bifur)/u/shodsdon/src]
3 %cc b.c
[shodsdon@(bifur)/u/shodsdon/src]
4 %a.out
-18
18
[shodsdon@(bifur)/u/shodsdon/src]
5 %cc -O b.c
[shodsdon@(bifur)/u/shodsdon/src]
6 %a.out
-18
-18
[shodsdon@(bifur)/u/shodsdon/src]
7 %cc -O0 b.c
[shodsdon@(bifur)/u/shodsdon/src]
8 %a.out
18
18


Kinda makes you wonder.

> _________________________________________________________________________
> Peter Davids   Lehrstuhl fuer Informatik IV   RWTH Aachen   D-5100 Aachen
> Tel. +241-804522    Fax: +241-806295     davids@informatik.rwth-aachen.de


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