}
                  throw new NoSuchFieldError("the Unsafe");
                });
      } catch (PrivilegedActionException e) {
        throw new RuntimeException("Could not initialize intrinsics", e.getCause());
      }
    }

    static {
      theUnsafe = getUnsafe();
      BYTE_ARRAY_BASE_OFFSET = theUnsafe.arrayBaseOffset(byte[].class);

      // sanity check - this should never fail

                }
                throw new NoSuchFieldError("the Unsafe");
              }
            });
      } catch (PrivilegedActionException e) {
        throw new RuntimeException("Could not initialize intrinsics", e.getCause());
      }
    }

    private volatile RunnableExecutorPair head = NULL_PAIR;

    public void add(Runnable runnable, Executor executor) {