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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug rtl-optimization/105453] [9/10/11 Regression] load introduced
 by ce1 for conditional loads at -O1, might cause issues with the C/C++ memory
 model
Date: Tue, 03 May 2022 07:24:14 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D105453

--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #1)
> There is no issue here as there is no atomic barrier as required by the c=
11
> and c++11 standards in their memory model

I agree that GCC's output is allowed by the memory model. If another thread=
 is
changing either of those globals then func_1 needs to be synchronised with =
it
to avoid data races, i.e. it would have undefined behaviour anyway, whatever
code GCC generated.=