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        Tue, 26 Apr 2016 07:44:40 -0700 (PDT)
Subject: Re: [PATCH] Don't divide by zero when trying to destroy an
 uninitialised barrier.
To: Florian Weimer <fweimer@redhat.com>
References: <5717B2F4.9050105@starleaf.com> <5717B657.6040007@arm.com>
 <5717D575.40806@starleaf.com> <5717DCA6.1090809@linaro.org>
 <571F7D5F.2080603@redhat.com>
Cc: libc-alpha@sourceware.org
From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Message-ID: <571F7ED0.9040001@linaro.org>
Date: Tue, 26 Apr 2016 14:44:00 -0000
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On 26/04/2016 11:38, Florian Weimer wrote:
> On 04/20/2016 09:46 PM, Adhemerval Zanella wrote:
>> I do not see a compelling reason to not return EINVAL if the UB
>> could be detected and if POSIX stated this behaviour is recommended.
> 
> It would result in silent loss of synchronization if the return value is not checked.  Such bugs are difficult to track down.
> 
> Florian

But the check is user responsibility and getting such error means the
program is doing something fuzzy.

But thinking twice seems that abort in such cases seems a better
alternative, it gives the user a more straightforward indication
he should check his code.