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List:       kde-devel
Subject:    Re: Comparing pointers via cast to int?
From:       Thiago Macieira <thiago.macieira () kdemail ! net>
Date:       2004-10-28 20:31:19
Message-ID: 200410281731.19377.thiago.macieira () kdemail ! net
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Adriaan de Groot wrote:
>Now, senderFrame and viewFrame are both QObject *, and what's worse is
> that an int isn't necessarily big enough to hold those pointers. 

Agreed. That's a bug on 64-bit platforms.

> Would either of
>
>      if ( senderFrame && viewFrame && viewFrame != senderFrame )
>
>      if ( senderFrame && viewFrame &&
>           (void *)viewFrame != (void *)senderFrame )

The first one is better.

If that generates a warning, cast one of the pointers to the other one's 
type, using static_cast.

Also note that two pointers of different types may differ and yet point to 
the same object! The original comparison is more than flawed.

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  Thiago Macieira  -  Registered Linux user #65028
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