Irony-mode was not enable by default in my c++mode

[algogavin]

I have the following in my .emacs.d/init.el file, I would expect it will enable the Irony mode when I open my C++ file, but it's not. As a workaround for now, I have to explicitly type "M-x irony-mode" to enable it.

; == irony-mode ==
(use-package irony
:ensure t
:defer t
:init
(add-hook 'c++-mode-hook 'irony-mode)
(add-hook 'c-mode-hook 'irony-mode)
(add-hook 'objc-mode-hook 'irony-mode)
:config
;; replace the completion-at-point' and complete-symbol' bindings in
;; irony-mode's buffers by irony-mode's function
(defun my-irony-mode-hook ()
(define-key irony-mode-map [remap completion-at-point]
'irony-completion-at-point-async)
(define-key irony-mode-map [remap complete-symbol]
'irony-completion-at-point-async))
(add-hook 'irony-mode-hook 'my-irony-mode-hook)
(add-hook 'irony-mode-hook 'irony-cdb-autosetup-compile-options)
;; (add-hook 'irony-mode-hook 'irony-eldoc)
)

I also try to add these as suggested-->
(add-hook 'c++-mode-hook 'irony-mode)
(add-hook 'c-mode-hook 'irony-mode)
(add-hook 'objc-mode-hook 'irony-mode)
(add-hook 'irony-mode-hook 'irony-cdb-autosetup-compile-options)

but it's not helping though. Any help?