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From: "Amar Memic" <amemic@uni-osnabrueck.de>
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Date: Wed, 21 Jul 2021 10:20:32 +0200
Subject: 6.55 Built-in Functions for Memory Model Aware Atomic Operations
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Hi,6.55 Built-in Functions for Memory Model Aware Atomic Operations (ht=
tps://gcc.gnu.org/onlinedocs/gcc/=5F005f=5F005fatomic-Builtins.html)=C2=
=A0 says:Note that the =E2=80=98=5F=5Fatomic=E2=80=99 builtins assume t=
hat programs will conform to the C++11 memory model. In particular, the=
y assume that programs are free of data races. See the C++11 standard f=
or detailed requirements.

I think the second sentence is a bit misleading because atomics should =
handle data races.
Especially, interleaving read/write or write/write operations should be=
 well-defined.
If you assume that programs are free of data races, then you could not =
implement spinlock based on these atomics, for example.
I hope you can help me to interpret the paragraph in the right manner.=C2=
=A0

Thanks in advance
Amar Memic