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From: "rguenth 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 08:09:58 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D94631

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #3)
> (In reply to Rich Felker from comment #2)
> > So basically the outcome of DR120 was allowing the GCC behavior? It sti=
ll
> > seems like a bad thing, not required, and likely to produce exploitable=
 bugs
> > (due to truncation of arithmetic) as well as very poor-performance code=
 (due
> > to constant masking).
>=20
> Note this only matters when the size of the bit-field is less than the si=
ze
> of int.

bigger than the size of int (due to default integer promotions still applyi=
ng).=