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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug other/94629] 10 issues located by the PVS-studio static analyzer
Date: Fri, 17 Apr 2020 10:31:25 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D94629

--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Comment on attachment 48299
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=3D48299
sorted list of redundant assignments

  /* If there were any declarations or structure tags in that level,
     or if this level is a function body,
     create a BLOCK to record them for the life of this function.  */
  block =3D NULL_TREE;
  /* Avoid function body block if possible.  */
  if (functionbody && subblocks && BLOCK_CHAIN (subblocks) =3D=3D NULL_TREE)
    keep =3D 0;
  else if (keep =3D=3D 1 || functionbody)
    block =3D make_node (BLOCK);
  if (block !=3D NULL_TREE)
    {
      BLOCK_VARS (block) =3D decls;
      BLOCK_SUBBLOCKS (block) =3D subblocks;
    }

  /* In each subblock, record that this is its superior.  */
  if (keep >=3D 0)
    for (link =3D subblocks; link; link =3D BLOCK_CHAIN (link))
      BLOCK_SUPERCONTEXT (link) =3D block;
certainly doesn't look like redundant assignment, yes, the block =3D NULL_T=
REE
could be moved into the if, but that is just programming style.
I must say I don't understand why the separate if (block !=3D NULL_TREE) is=
 in
there, perhaps from historic reasons there might have been more cases.
Now it would make much more sense to just do
  else if (keep =3D=3D 1 || functionbody)
    {
      block =3D make_node (BLOCK);
      BLOCK_VARS (block) =3D decls;
      BLOCK_SUBBLOCKS (block) =3D subblocks;
    }=