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From: "burnus at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/95622] [11 Regression] force_output flag on a
 variable prevents optimization  / regresses
 c-c++-common/goacc/kernels-alias-ipa-pta{-2,-4,}.c
Date: Wed, 15 Jul 2020 07:06:24 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D95622

--- Comment #7 from Tobias Burnus <burnus at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #6)
> not sure if fixed?

Not fixed =E2=80=93 only XFAILed.

The issue is that optimizations are not done with "node->force_output". As =
in
the example in comment 0:
  "a =3D 0; c =3D a"  will become
    "c[0] =3D 0"    without force_output
but "c[0] =3D a[0]"    with force_output set.

As the variable has been already used in the offload-variable table, it can=
not
be removed for good =E2=80=93 but not using it is fine.=