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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug libstdc++/99117] [9/10/11 Regression] cannot accumulate
 std::valarray
Date: Tue, 16 Feb 2021 11:25:33 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D99117

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to work|7.5.0, 8.4.0                |
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
int* p =3D sum._M_data;
int* e1 =3D sum._M_data;

If p and e1 aren't __restrict__ too, shouldn't that be fine?  Reading the s=
ame
value multiple times shouldn't create new clique each time it is read.
Though, isn't it before optimization a different argument instead?
I'd think even that should be ok, because using __restrict__ from FIELD_DEC=
Ls
is only ok if we can prove it is different structs (say pointers to them al=
so
being restrict), but the current aliasing code probably doesn't do that.=