[Bug tree-optimization/104316] RSO is not used when doing assignment rather than initialization and address taken afterwards

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104316

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2022-01-31
     Ever confirmed|0                           |1

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
NRV has:
static bool
dest_safe_for_nrv_p (gcall *call)
{
  tree dest = gimple_call_lhs (call);

  dest = get_base_address (dest);
  if (! dest)
    return false;

  if (TREE_CODE (dest) == SSA_NAME)
    return true;

  if (call_may_clobber_ref_p (call, dest, false)
      || ref_maybe_used_by_stmt_p (call, dest, false))
    return false;

  return true;
}

Which is fine, the problem is the clobber list is not exactly flow senative, I
think there is another bug about that.