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Date: Thu, 10 Mar 2005 10:43:55 +0000
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Subject: Re: [PHP-DEV] Re: [PATCH] exif warning fix?
From: jorton@redhat.com (Joe Orton)

On Thu, Mar 10, 2005 at 11:23:51AM +0100, Ard Biesheuvel wrote:
> Joe Orton wrote:
> >Testing "length >= LONG_MAX" where length is an int is always false, and
> >gcc gives a warning for it.  Perhaps something like this was intended?
> >
> 
> On 64-bit it is always false, however on 32-bit 'length == LONG_MAX' can 
> be true. That's probably why noone caught the warning so far, as gcc 
> would not emit it on a 32-bit system.
> 
> If you're testing for overflow, casting to unsigned int won't help you 
> here, as the overflow will already have occurred when length was 
> assigned its value.

Yes, sorry, I haven't turned my brain on yet this morning.  So perhaps a
test for (length < 0) is all that's really needed; I can't see why
length == INT_MAX is particularly a special case here...

joe