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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug ipa/103875] Dead writes are not optimized out
Date: Tue, 04 Jan 2022 14:09:03 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D103875

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
The clobber is gone at the point we inline pop(), CDDCE1 removes it because
the clobbered address computation is dead.

Eliminating unnecessary statements:
Deleting : *_4 =3D{v} {CLOBBER};

Deleting : _4 =3D &this_6(D)->data[_2];

IL before CDDCE:

  <bb 2> :
  _1 =3D this_6(D)->size;
  _2 =3D _1 + 18446744073709551615;
  this_6(D)->size =3D _2;
  _4 =3D &this_6(D)->data[_2];
  *_4 =3D{v} {CLOBBER};
  return;=