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From: "mpolacek at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c++/98947] [10/11 Regression] Incorrect warning when using a
 ternary operator to select one of two volatile variables to write to
Date: Wed, 03 Feb 2021 22:49:22 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D98947

Marek Polacek <mpolacek at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|Incorrect warning when      |[10/11 Regression]
                   |using a ternary operator to |Incorrect warning when
                   |select one of two volatile  |using a ternary operator to
                   |variables to write to       |select one of two volatile
                   |                            |variables to write to
           Priority|P3                          |P2
   Target Milestone|---                         |10.3

--- Comment #2 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
I think warning on

  (b ? x : y) =3D 27;

is bogus, therefore I'd argue that this is a regression; gcc 9 didn't issue=
 any
warnings with -std=3Dc++2a.

I have a patch.  Of course, we should still warn for

(b ? x : y) +=3D 27;
(b ? (x =3D 24) : y) =3D 25;

etc.=