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From: "glisse at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/107065] GCC treats rvalue as an lvalue
Date: Fri, 30 Sep 2022 08:47:38 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107065

--- Comment #13 from Marc Glisse <glisse at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #12)
> Doing it on the match.pd side doesn't look right, there could be many oth=
er
> optimizations that result in something similar.

$ grep -c non_lvalue match.pd=20=20=20
12

probably they should be removed and those that were useful should be fixed =
by
similar techniques as you are considering...

To add one more option to your list, maybe the generic-simplify machinery c=
ould
add non_lvalue automatically in some cases? I still prefer your first option
though, tweaking the warning code, which probably expected x!=3D0 and now g=
ets
!(x=3D=3D0) or something similar.=