[Bug middle-end/69547] [6 regression] no-op array initializer emits an empty loop

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69547

Richard Biener <rguenth at gcc dot gnu.org> changed:

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

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
Hmm, so we have

  <bb 3>:
  # _1 = PHI <&a(2), _9(4)>
  # _2 = PHI <63(2), _10(4)>
  if (_2 == -1)
    goto <bb 5>;
  else
    goto <bb 4>;

  <bb 4>:
  MEM[(struct  &)_1] ={v} {CLOBBER};
  _9 = _1 + 1;
  _10 = _2 + -1;
  goto <bb 3>;

in CDDCE and do

processing: foo (&a, 64);

marking necessary through .MEM_15 stmt MEM[(struct  &)_1] ={v} {CLOBBER};
processing: MEM[(struct  &)_1] ={v} {CLOBBER};

I'm trying a patch to fix that.