* Bug

Step 1: place the foo code block below into a different file and ingest that
file into the library of babel.  (It must be in a separate file for the
bug to manifest.)

#+name: foo
#+BEGIN_SRC emacs-lisp
  2
#+END_SRC

Step 2: evaluate this code block.  The result should be =(:results . replace)=

#+BEGIN_SRC emacs-lisp :results append
  (assq :results (nth 2 (cdr (assq 'foo org-babel-library-of-babel))))
#+END_SRC

#+RESULTS:
: (:results . replace)
: (:results . silent)

Step 3: evaluate this source block:

#+BEGIN_SRC emacs-lisp :var bar=foo
  bar
#+END_SRC

#+RESULTS:
: 2

Step 4: re-evaluate the block from step 2.  The result should be =(:results . silent)=