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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/109578] fail to remove dead code due to division by
 zero
Date: Thu, 20 Apr 2023 21:37:38 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D109578

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Vincent Lef=C3=A8vre from comment #2)
> (In reply to Andrew Pinski from comment #1)
> > We don't removing code before undefined behavior ...
> > That is GCC does not know that printf  does not have side effects.
>=20
> Then GCC is incorrect in bug 29968, because it does the division *before*
> the printf.

Or was a bug which has since been fixed.

For sparc GCC 12.2.0 we get:
        sethi   %hi(.LC0), %o0
        call    puts, 0
         or     %o0, %lo(.LC0), %o0
        ta      5

Anyways maybe the issue with PR 29968 was a scheduling issue which was fixed
later on that GCC didn't realize divide could trap.=