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From: Andreas Schwab <schwab@linux-m68k.org>
To: David Brown <david.brown@hesbynett.no>
Cc: AJ D <aatsnps@gmail.com>,  gcc@gcc.gnu.org
Subject: Re: Comma Operator - Left to Right Associativity
References: <CAJMvVjbSMvzm8P_f2_meEhy6OTPyvsxWURHauT7w4UvcVbadjA@mail.gmail.com>
 <59add9a1-ef9b-1cde-a4b7-66a167595a6b@hesbynett.no>
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Date: Thu, 04 Feb 2021 22:21:18 +0100
In-Reply-To: <59add9a1-ef9b-1cde-a4b7-66a167595a6b@hesbynett.no> (David
 Brown's message of "Thu, 4 Feb 2021 21:58:33 +0100")
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On Feb 04 2021, David Brown wrote:

> For the built-in comma operator, you get guaranteed order of evaluation
> (or more precisely, guaranteed order of visible side-effects).  But for
> a user-defined comma operator, you do not - until C++17, which has
> guaranteed evaluation ordering in some circumstances.

But not the evaluation order of function arguments.  See
<https://en.cppreference.com/w/cpp/language/eval_order> Sequenced-before
rules, rule 15.

> Try your test again with "-std=c++17" or "-std=g++17" - if the order is
> still reversed, it's a gcc bug (AFAICS).

I don't think so.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
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