diff --git a/core/imageboard.pack.php b/core/imageboard.pack.php
index 4d46b200..a88461bb 100644
--- a/core/imageboard.pack.php
+++ b/core/imageboard.pack.php
@@ -75,6 +75,8 @@ class Image {
 	 * @param null|mixed $row
 	 */
 	public function __construct($row=null) {
+		assert('is_null($row) || is_array($row)');
+
 		if(!is_null($row)) {
 			foreach($row as $name => $value) {
 				// some databases use table.name rather than name
diff --git a/core/util.inc.php b/core/util.inc.php
index 95eb318b..dbbcf9b3 100644
--- a/core/util.inc.php
+++ b/core/util.inc.php
@@ -82,7 +82,7 @@ function sql_escape($input) {
  * Turn all manner of HTML / INI / JS / DB booleans into a PHP one
  *
  * @param $input
- * @return boolean
+ * @return bool
  */
 function bool_escape($input) {
 	/*
@@ -234,7 +234,7 @@ function autodate($date, $html=true) {
  * Check if a given string is a valid date-time. ( Format: yyyy-mm-dd hh:mm:ss )
  *
  * @param $dateTime
- * @return boolean
+ * @return bool
  */
 function isValidDateTime($dateTime) {
 	if (preg_match("/^(\d{4})-(\d{2})-(\d{2}) ([01][0-9]|2[0-3]):([0-5][0-9]):([0-5][0-9])$/", $dateTime, $matches)) {
@@ -250,7 +250,7 @@ function isValidDateTime($dateTime) {
  * Check if a given string is a valid date. ( Format: yyyy-mm-dd )
  *
  * @param $date
- * @return boolean
+ * @return bool
  */
 function isValidDate($date) {
 	if (preg_match("/^(\d{4})-(\d{2})-(\d{2})$/", $date, $matches)) {
@@ -1052,7 +1052,7 @@ if (!function_exists('http_parse_headers')) { #http://www.php.net/manual/en/func
  * In cases like these, we need to make sure to check for them if the camelcase version does not exist.
  * 
  * @param array $headers
- * @param mixed $key
+ * @param mixed $name
  * @return mixed
  */
 function findHeader ($headers, $name) {
@@ -1140,29 +1140,29 @@ define("SCORE_LOG_NOTSET", 0);
  * @param string $section
  * @param int $priority
  * @param string $message
- * @param null|bool|string $flash
+ * @param bool|string $flash
  * @param array $args
  */
-function log_msg(/*string*/ $section, /*int*/ $priority, /*string*/ $message, $flash=null, $args=array()) {
+function log_msg(/*string*/ $section, /*int*/ $priority, /*string*/ $message, $flash=false, $args=array()) {
 	send_event(new LogEvent($section, $priority, $message, $args));
 	$threshold = defined("CLI_LOG_LEVEL") ? CLI_LOG_LEVEL : 0;
 	if(is_cli() && ($priority >= $threshold)) {
 		print date("c")." $section: $message\n";
 	}
-	if($flash === True) {
+	if($flash === true) {
 		flash_message($message);
 	}
-	else if(!is_null($flash)) {
+	else if(is_string($flash)) {
 		flash_message($flash);
 	}
 }
 
 // More shorthand ways of logging
-function log_debug(   /*string*/ $section, /*string*/ $message, $flash=null, $args=array()) {log_msg($section, SCORE_LOG_DEBUG, $message, $flash, $args);}
-function log_info(    /*string*/ $section, /*string*/ $message, $flash=null, $args=array()) {log_msg($section, SCORE_LOG_INFO, $message, $flash, $args);}
-function log_warning( /*string*/ $section, /*string*/ $message, $flash=null, $args=array()) {log_msg($section, SCORE_LOG_WARNING, $message, $flash, $args);}
-function log_error(   /*string*/ $section, /*string*/ $message, $flash=null, $args=array()) {log_msg($section, SCORE_LOG_ERROR, $message, $flash, $args);}
-function log_critical(/*string*/ $section, /*string*/ $message, $flash=null, $args=array()) {log_msg($section, SCORE_LOG_CRITICAL, $message, $flash, $args);}
+function log_debug(   /*string*/ $section, /*string*/ $message, $flash=false, $args=array()) {log_msg($section, SCORE_LOG_DEBUG, $message, $flash, $args);}
+function log_info(    /*string*/ $section, /*string*/ $message, $flash=false, $args=array()) {log_msg($section, SCORE_LOG_INFO, $message, $flash, $args);}
+function log_warning( /*string*/ $section, /*string*/ $message, $flash=false, $args=array()) {log_msg($section, SCORE_LOG_WARNING, $message, $flash, $args);}
+function log_error(   /*string*/ $section, /*string*/ $message, $flash=false, $args=array()) {log_msg($section, SCORE_LOG_ERROR, $message, $flash, $args);}
+function log_critical(/*string*/ $section, /*string*/ $message, $flash=false, $args=array()) {log_msg($section, SCORE_LOG_CRITICAL, $message, $flash, $args);}
 
 
 $_request_id = null;
diff --git a/ext/arrowkey_navigation/main.php b/ext/arrowkey_navigation/main.php
index bf7350c3..75cc22bd 100644
--- a/ext/arrowkey_navigation/main.php
+++ b/ext/arrowkey_navigation/main.php
@@ -67,7 +67,7 @@ class ArrowkeyNavigation extends Extension {
 		$images_per_page = $config->get_int('index_images');
 
 		// if there are no tags, use default
-		if ($event->get_arg(1) == null){
+		if (is_null($event->get_arg(1))){
 			$prefix = "";
 			$page_number = int_escape($event->get_arg(0));
 			$total_pages = ceil($database->get_one(
diff --git a/ext/oekaki/main.php b/ext/oekaki/main.php
index b9081fe1..0894dd2c 100644
--- a/ext/oekaki/main.php
+++ b/ext/oekaki/main.php
@@ -33,15 +33,15 @@ class Oekaki extends Extension {
 						$metadata['extension'] = $pathinfo['extension'];
 						$metadata['tags'] = 'oekaki tagme';
 						$metadata['source'] = null;
-						$event = new DataUploadEvent($tmpname, $metadata);
-						send_event($event);
-						if($event->image_id == -1) {
+						$duev = new DataUploadEvent($tmpname, $metadata);
+						send_event($duev);
+						if($duev->image_id == -1) {
 							throw new UploadException("File type not recognised");
 						}
 						else {
 							unlink($tmpname);
 							$page->set_mode("redirect");
-							$page->set_redirect(make_link("post/view/".$event->image_id));
+							$page->set_redirect(make_link("post/view/".$duev->image_id));
 						}
 					}
 				}
diff --git a/ext/upload/main.php b/ext/upload/main.php
index c63af261..9e8fb062 100644
--- a/ext/upload/main.php
+++ b/ext/upload/main.php
@@ -159,6 +159,7 @@ class Upload extends Extension {
 					$source = isset($_POST['source']) ? $_POST['source'] : null;
 					$tags = ''; // Tags aren't changed when uploading. Set to null to stop PHP warnings.
 					
+					$ok = false;
 					if(count($_FILES)) {
 						foreach($_FILES as $file) {
 							$ok = $this->try_upload($file, $tags, $source, $image_id);
@@ -177,6 +178,7 @@ class Upload extends Extension {
 				}
 				else if(!empty($_GET['url'])) {
 					$url = $_GET['url'];
+					$tags = isset($_GET['tags']) ? $_GET['tags'] : 'tagme';
 					$source = isset($_GET['source']) ? $_GET['source'] : $url;
 					$ok = $this->try_transload($url, $tags, $source, $image_id);
 					$this->theme->display_upload_status($page, $ok);