Re: [PATCH v3 2/2] bsearch: prevent overflow when computing middle comparison element
From: Rusty Russell
Date: Tue Nov 10 2009 - 19:18:55 EST
On Tue, 10 Nov 2009 02:12:31 am Andrà Goddard Rosa wrote:
> It's really difficult to occur in practice because the sum of the lower
> and higher limits must overflow an int variable, but it can occur when
> working with large arrays. We'd better safe than sorry by avoiding this
> overflow situation when computing the middle element for comparison.
I always thought the obvious answer was:
mid = start + (end - start)/2;
Your version does nothing for 32 bit platforms...
Rusty.
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