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From: "jvdelisle at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug fortran/98426] find_symbol in module.c traverses O(N) part of a
 search tree
Date: Wed, 24 Apr 2024 03:05:03 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D98426

--- Comment #8 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> ---
Martin or Matt,

Can you test the following variation to see if you get better results.

        return st;
    }

  retval =3D NULL;
  if (c <=3D 0)
    retval =3D find_symbol (st->left, name, module, generic);

  if (c > 0 && retval =3D=3D NULL)
    retval =3D find_symbol (st->right, name, module, generic);

  if (c > 0 && retval =3D=3D NULL)
    retval =3D find_symbol (st->left, name, module, generic);

  if (c <=3D 0 && retval =3D=3D NULL)
    retval =3D find_symbol (st->right, name, module, generic);

  return retval;

This does pass regression testing but I do not think it guarantees better
results.  Apparently the value of c does not guarantee a find going left or
right.=