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Subject: Re: [PATCH v3 4/6] stdlib: Sync canonicalize with gnulib [BZ #10635]
 [BZ #26592] [BZ #26341] [BZ #24970]
To: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Cc: bug-gnulib@gnu.org, libc-alpha@sourceware.org
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From: Paul Eggert <eggert@cs.ucla.edu>
Organization: UCLA Computer Science Department
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Date: Fri, 8 Jan 2021 17:24:14 -0800
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On 1/4/21 4:52 AM, Adhemerval Zanella wrote:
> The extra comparison might avoid the scratch_buffer resize that will
> fail (since malloc will fail to try allocate PTRDIFF_MAX object), but
> it will be used only when such objects are provided (which depending
> of the system should not happen).

As you say, that comparison isn't needed for glibc. It's also not needed 
on non-glibc because Gnulib prevents malloc etc. from succeeding on 
sizes greater than PTRDIFF_MAX. So we should be OK here.