[Bug middle-end/78295] [7 Regression] Spurious -Wuninitialized warning for vector element assignment

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78295

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 #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
The late uninit pass warns about

;; 2 loops found
f (double x)
{
  int i;
  vectype t;

  <bb 2>:
  t_16 = BIT_INSERT_EXPR <t_12(D), x_6(D), 0 (64 bits)>;
  t_2 = BIT_INSERT_EXPR <t_16, x_6(D), 64 (64 bits)>;
  return t_2;

}

where the first statement constitutes a partial initialization of the
previously completely uninitialized t_12(D).  In BIT_INSERT_EXPR the
first argument is a "destination" and thus should not constitute a use
by late uninit.