[Bug middle-end/19430] taking address of a var causes missing uninitialized warning

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=19430

--- Comment #29 from Richard Biener <rguenth at gcc dot gnu.org> ---
What remains seems to be complaining that

  int i;
  foo (&i);

doesn't warn.  And we have another bug that

  int i;
  foo (&i);
  ... = i;

doesn't warn for the read from i.

I think both of these need a different warning level as foo may not read
from i and foo may initialize i.