diff --git a/core/includes/bootstrap.inc b/core/includes/bootstrap.inc
index 207fdda..e3a158f 100644
--- a/core/includes/bootstrap.inc
+++ b/core/includes/bootstrap.inc
@@ -539,6 +539,9 @@ function t($string, array $args = array(), array $options = array()) {
  * @see \Drupal\Component\Utility\String::format()
  * @see t()
  * @ingroup sanitization
+ *
+ * @deprecated in Drupal 8.x-dev, will be removed before Drupal 8.0.0.
+ *   Use \Drupal\Component\Utility\String::format().
  */
 function format_string($string, array $args = array()) {
   return String::format($string, $args);
@@ -569,6 +572,9 @@ function format_string($string, array $args = array()) {
  *   TRUE if the text is valid UTF-8, FALSE if not.
  *
  * @see \Drupal\Component\Utility\Unicode::validateUtf8()
+ *
+ * @deprecated in Drupal 8.x-dev, will be removed before Drupal 8.0.0.
+ *   Use \Drupal\Component\Utility\Unicode::validateUtf8().
  */
 function drupal_validate_utf8($text) {
   return Unicode::validateUtf8($text);
@@ -1168,8 +1174,13 @@ function request_path() {
 }
 
 /**
+ * Internal use only
+ *
  * @todo This is a temporary function pending refactoring Drupal to use
  *   Symfony's Request object exclusively.
+ *
+ * @deprecated in Drupal 8.x-dev, will be removed before Drupal 8.0.0.
+ *   by https://www.drupal.org/node/2237001.
  */
 function _current_path($path = NULL) {
   static $current_path = '';
@@ -1353,6 +1364,9 @@ function drupal_static_reset($name = NULL) {
  * Formats text for emphasized display in a placeholder inside a sentence.
  *
  * @see \Drupal\Component\Utility\String::placeholder()
+ *
+ * @deprecated in Drupal 8.x-dev, will be removed before Drupal 8.0.0.
+ *   Use \Drupal\Component\Utility\String::placeholder().
  */
 function drupal_placeholder($text) {
   return String::placeholder($text);
diff --git a/core/includes/common.inc b/core/includes/common.inc
index 4163da2..3846d3d 100644
--- a/core/includes/common.inc
+++ b/core/includes/common.inc
@@ -323,6 +323,10 @@ function valid_email_address($mail) {
  *
  * @see \Drupal\Component\Utility\UrlHelper::stripDangerousProtocols()
  * @see \Drupal\Component\Utility\String::checkPlain()
+ *
+ * @deprecated in Drupal 8.x-dev, will be removed before Drupal 8.0.0.
+ *   Use \Drupal\Component\Utility\String::checkPlain().
+ *
  */
 function check_url($uri) {
   return String::checkPlain(UrlHelper::stripDangerousProtocols($uri));
@@ -508,6 +512,9 @@ function format_size($size, $langcode = NULL) {
  *   A translated date string in the requested format.
  *
  * @see \Drupal\Component\Datetime\DateFormatter::format()
+ *
+ * @deprecated in Drupal 8.x-dev, will be removed before Drupal 8.0.
+ *   Use \Drupal::service('date.formatter')->format().
  */
 function format_date($timestamp, $type = 'medium', $format = '', $timezone = NULL, $langcode = NULL) {
   return \Drupal::service('date.formatter')->format($timestamp, $type, $format, $timezone, $langcode);