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From: wolfgang@ruso.UUCP (Wolfgang Deifel)
Newsgroups: comp.lang.c
Subject: Re: swap(x,y)
Message-ID: <1005@ruso.UUCP>
Date: 28 Aug 89 08:32:04 GMT
References: <MYwDEFy00WB842JEUx@andrew.cmu.edu> <1061@virtech.UUCP> <17504@ut-emx.UUCP>
Organization: Dr. Ruff Software GmbH, Aachen, W.Germany
Lines: 27

pmaniac@walt.cc.utexas.edu (Noah Friedman) writes:

>void swap(double *x, double *y) 
>{
>    *x += *y;
>    *y = *x - *y;
>    *x -= *y;
>}

>func()
>{
> int a, b;

>    ...
>    swap((double *) &a, (double *) &b);
>    ...
>}

I think, this function never works right. If you cast the adress of
an integer to adress of double, you don't cast the int to double.
What you wanted to do is ( I think ), &((double)a) but this also
doesn't work, because (double)a is an r-value which has no adress.

--
Wolfgang Deifel
Dr. Ruff Software GmbH, 5100 Aachen, Juelicherstr. 65-67, W-Germany
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