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From: "rsandifo at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/94994] [10/11 Regression] possible miscompilation of
 word-at-a-time copy via packed structs
Date: Wed, 30 Dec 2020 11:24:16 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D94994

rsandifo at gcc dot gnu.org <rsandifo at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |rsandifo at gcc dot=
 gnu.org

--- Comment #4 from rsandifo at gcc dot gnu.org <rsandifo at gcc dot gnu.or=
g> ---
Seems to be caused by:

/* Get the minimum alignment for all the scalar accesses that DR_INFO
   describes.  */

static unsigned int
vect_vfa_align (dr_vec_info *dr_info)
{
  return TYPE_ALIGN_UNIT (TREE_TYPE (DR_REF (dr_info->dr)));
}

providing duff alignment information.  Changing it to:

  return dr_alignment (dr_info->dr);

fixes the bug.=