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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/94631] Wrong codegen for arithmetic on bitfields
Date: Fri, 17 Apr 2020 05:34:36 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D94631

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Rich Felker from comment #2)
> So basically the outcome of DR120 was allowing the GCC behavior? It still
> seems like a bad thing, not required, and likely to produce exploitable b=
ugs
> (due to truncation of arithmetic) as well as very poor-performance code (=
due
> to constant masking).

Note this only matters when the size of the bit-field is less than the size=
 of
int.=