From: Simon 'corecode' Schubert <corecode@fs.ei.tum.de>
Date: Thu, 18 Jan 2007 14:56:06 GMT
Subject: Re: [PATCH 2/2] Use fixed-size integers for .idx file I/O
Message-ID: <45AF8A86.7070101@fs.ei.tum.de>
In-Reply-To: <118833cc0701180651w3b5ac164m4e396399f1d58cb7@mail.gmail.com>

Morten Welinder wrote:
>> -                       return ntohl(*((unsigned int *) ((char *) 
>> index + (24 * mi))));
>> +                       return ntohl(*((uint32_t *)((char *)index + 
>> (24 * mi))));
> 
> Is that pointer gymnastics guaranteed to work?  I.e., how do we know
> that we can access an uint32_t (or unsigned) at such an address?

if index is always aligned to a 4-byte boundary, this is safe.  apart from that, the problem already existed.

cheers
  simon

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