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From: "kargl at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug fortran/30409] [fortran] missed optimization with pure function
 arguments
Date: Mon, 23 Oct 2023 21:45:27 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D30409

--- Comment #12 from kargl at gcc dot gnu.org ---
(In reply to anlauf from comment #11)
> (In reply to kargl from comment #10)
> > (In reply to anlauf from comment #8)
>=20
> > which is equivalent to=20
> >=20
> >    tmp =3D 1 / y
> >    do i =3D 1, n
> >       ... =3D expression1(..., tmp)
> >    end do
>=20
> No.  Strictly speaking, it is only equivalent to:
>=20
>     if (n > 0) tmp =3D 1 / y
>     do i =3D 1, n
>        ... =3D expression1(..., tmp)
>     end do

Ah, yes, I missed the possibility that the loop may not loop at all.=