diff --git a/wp-includes/formatting.php b/wp-includes/formatting.php
index fc1b1509e0..6dc87e2d18 100644
--- a/wp-includes/formatting.php
+++ b/wp-includes/formatting.php
@@ -3264,7 +3264,6 @@ function sanitize_text_field($str) {
 		$filtered = trim( preg_replace('/[\r\n\t ]+/', ' ', $filtered) );
 	}
 
-	$match = array();
 	$found = false;
 	while ( preg_match('/%[a-f0-9]{2}/i', $filtered, $match) ) {
 		$filtered = str_replace($match[0], '', $filtered);
diff --git a/wp-includes/media.php b/wp-includes/media.php
index 36736cef20..52037b959a 100644
--- a/wp-includes/media.php
+++ b/wp-includes/media.php
@@ -1908,7 +1908,6 @@ function get_attached_video( $post_id = 0 ) {
  */
 function get_content_media( $type, &$content, $html = true, $remove = false, $limit = 0 ) {
 	$items = array();
-	$matches = array();
 
 	if ( preg_match_all( '/' . get_shortcode_regex() . '/s', $content, $matches, PREG_SET_ORDER ) && ! empty( $matches ) ) {
 		foreach ( $matches as $shortcode ) {
@@ -1927,7 +1926,6 @@ function get_content_media( $type, &$content, $html = true, $remove = false, $li
 	if ( $html )
 		return $items;
 
-	$src = '';
 	$data = array();
 
 	foreach ( $items as $item ) {
@@ -1958,7 +1956,6 @@ function get_content_media( $type, &$content, $html = true, $remove = false, $li
  */
 function get_embedded_media( $type, &$content, $remove = false, $limit = 0 ) {
 	$html = array();
-	$matches = '';
 
 	foreach ( array( $type, 'object', 'embed', 'iframe' ) as $tag ) {
 		if ( preg_match( '#' . get_tag_regex( $tag ) . '#', $content, $matches ) ) {
@@ -2206,7 +2203,6 @@ function get_attached_image_srcs( $post_id = 0 ) {
  * @return array The found images or srcs
  */
 function get_content_images( &$content, $html = true, $remove = false, $limit = 0 ) {
-	$matches = array();
 	$tags = array();
 	$captions = array();
 
@@ -2255,7 +2251,6 @@ function get_content_images( &$content, $html = true, $remove = false, $limit =
 	if ( $html )
 		return $tags;
 
-	$src = '';
 	$srcs = array();
 
 	foreach ( $tags as $tag ) {
@@ -2300,9 +2295,7 @@ function get_content_image( &$content, $html = true, $remove = false ) {
  * @return array A list of galleries, which in turn are a list of their srcs in order
  */
 function get_content_galleries( &$content, $html = true, $remove = false, $limit = 0 ) {
-	$src = '';
 	$galleries = array();
-	$matches = array();
 
 	if ( preg_match_all( '/' . get_shortcode_regex() . '/s', $content, $matches, PREG_SET_ORDER ) && ! empty( $matches ) ) {
 		foreach ( $matches as $shortcode ) {
@@ -2493,7 +2486,6 @@ function get_the_post_format_image( $attached_size = 'full', &$post = null ) {
 		$urls[] = get_attachment_link( $media->ID );
 
 		$count = 1;
-		$matches = array();
 		$content = $post->post_content;
 
 		if ( preg_match_all( '/' . get_shortcode_regex() . '/s', $content, $matches, PREG_SET_ORDER ) && ! empty( $matches ) ) {
diff --git a/wp-includes/post-formats.php b/wp-includes/post-formats.php
index 3bb380a612..e8b92ba0e9 100644
--- a/wp-includes/post-formats.php
+++ b/wp-includes/post-formats.php
@@ -580,7 +580,6 @@ function get_content_chat( &$content, $remove = false ) {
 				continue;
 		}
 
-		$matches = array();
 		$matched = preg_match( $newline_regex, $line, $matches );
 		if ( ! $matched )
 			continue;
@@ -709,7 +708,6 @@ function get_content_quote( &$content, $remove = false, $replace = '' ) {
 	if ( empty( $content ) )
 		return '';
 
-	$matches = array();
 	if ( ! preg_match( '/<blockquote[^>]*>(.+?)<\/blockquote>/is', $content, $matches ) ) {
 		$quote = $content;
 		if ( $remove || ! empty( $replace ) )
@@ -783,8 +781,6 @@ function get_content_url( &$content, $remove = false ) {
 	if ( empty( $content ) )
 		return '';
 
-	$matches = array();
-
 	// the content is a URL
 	$trimmed = trim( $content );
 	if ( 0 === stripos( $trimmed, 'http' ) && ! preg_match( '#\s#', $trimmed ) ) {
@@ -883,7 +879,6 @@ function get_the_remaining_content( $more_link_text = null, $strip_teaser = fals
 
 	$output = '';
 	$has_teaser = false;
-	$matches = array();
 
 	// If post password required and it doesn't match the cookie.
 	if ( post_password_required() )
diff --git a/wp-includes/post-template.php b/wp-includes/post-template.php
index 23173997f7..a67b0e1435 100644
--- a/wp-includes/post-template.php
+++ b/wp-includes/post-template.php
@@ -185,7 +185,6 @@ function get_the_content( $more_link_text = null, $strip_teaser = false ) {
 
 	$output = '';
 	$has_teaser = false;
-	$matches = array();
 
 	// If post password required and it doesn't match the cookie.
 	if ( post_password_required() )
diff --git a/wp-includes/shortcodes.php b/wp-includes/shortcodes.php
index b7a0b1ba0b..a40959491b 100644
--- a/wp-includes/shortcodes.php
+++ b/wp-includes/shortcodes.php
@@ -152,7 +152,6 @@ function shortcode_exists( $tag ) {
  */
 function has_shortcode( $content, $tag ) {
 	if ( shortcode_exists( $tag ) ) {
-		$matches = array();
 		preg_match_all( '/' . get_shortcode_regex() . '/s', $content, $matches, PREG_SET_ORDER );
 		if ( empty( $matches ) )
 			return false;