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From: "vincent-gcc at vinc17 dot net" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/95057] missing -Wunused-but-set-variable warning on multiple
 assignments, not all of them used
Date: Mon, 11 May 2020 13:05:37 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D95057

--- Comment #2 from Vincent Lef=C3=A8vre <vincent-gcc at vinc17 dot net> ---
(In reply to Jakub Jelinek from comment #1)
> That is something this warning can't warn about.
> The warning is a simple FE warning that uses two bits, one for whether
> certain decl was used and one whether it was read.  The warning then
> diagnoses those that have the former bit set and not the latter (of cours=
e,
> there are some exceptions etc.).

But when the variable is assigned, the "read" bit could be reset.=