core: Fix free variable references

Most are innocuous. One is update-packages-alist in config layer. Define
the variable and give it a docstring with an explanation of its purpose.

core/core-configuration-layer.el

@@ -147,6 +147,10 @@ the path for this layer.")
   "List of strings corresponding to category names. A category is a
 directory with a name starting with `+'.")
 
+(defvar update-packages-alist '()
+  "Used to collect information about rollback packages in the
+cache folder.")
+
 (defun configuration-layer/initialize ()
   "Initialize `package.el'."
   (configuration-layer//parse-command-line-arguments)
@@ -699,7 +703,8 @@ path."
            (mapcar 'car
                    (object-assoc-list
                     :name configuration-layer--used-distant-packages))))
-         (noinst-count (length noinst-pkg-names)))
+         (noinst-count (length noinst-pkg-names))
+         installed-count)
     ;; installation
     (when noinst-pkg-names
       (spacemacs-buffer/append
@@ -1247,7 +1252,8 @@ to select one."
                    configuration-layer--used-distant-packages
                    implicit-packages
                    dependencies))
-         (orphans-count (length orphans)))
+         (orphans-count (length orphans))
+         deleted-count)
     ;; (message "dependencies: %s" dependencies)
     ;; (message "implicit: %s" implicit-packages)
     ;; (message "orphans: %s" orphans)

core/core-funcs.el

@@ -10,6 +10,9 @@
 ;;
 ;;; License: GPLv3
 
+(defvar configuration-layer--protected-packages)
+(defvar dotspacemacs-filepath)
+
 (defun spacemacs/load-or-install-protected-package (pkg &optional log file-to-load)
   "Load PKG package, and protect it against being deleted as an orphan.
 See `spacemacs/load-or-install-package' for more information."
@@ -231,6 +234,7 @@ result, incrementing passed-tests and total-tests."
 ;; hide mode line
 ;; from http://bzg.fr/emacs-hide-mode-line.html
 (defvar-local hidden-mode-line-mode nil)
+(defvar-local hide-mode-line nil)
 (define-minor-mode hidden-mode-line-mode
   "Minor mode to hide the mode-line in the current buffer."
   :init-value nil

core/core-release-management.el

@@ -18,6 +18,8 @@
 (defconst spacemacs-checkversion-branch "master"
   "Name of the branch used to check for new version.")
 
+(defvar dotspacemacs-check-for-update)
+(defvar spacemacs-version)
 ;; new version variables
 (defvar spacemacs-new-version nil
   "If non-nil a new Spacemacs version is available.")