diff --git a/lib/SimpleSAML/Error/AuthSource.php b/lib/SimpleSAML/Error/AuthSource.php
index f6caaf1ade47c71b9806526a06af0afb85835e37..0321e424c79ed137e621895cab422fe5b01692b4 100644
--- a/lib/SimpleSAML/Error/AuthSource.php
+++ b/lib/SimpleSAML/Error/AuthSource.php
@@ -4,6 +4,8 @@ declare(strict_types=1);
 
 namespace SimpleSAML\Error;
 
+use Throwable;
+
 /**
  * Baseclass for auth source exceptions.
  *
@@ -32,9 +34,9 @@ class AuthSource extends Error
      *
      * @param string $authsource  Authsource module name from where this error was thrown.
      * @param string $reason  Description of the error.
-     * @param \Exception|null $cause
+     * @param \Throwable|null $cause
      */
-    public function __construct($authsource, $reason, $cause = null)
+    public function __construct(string $authsource, string $reason, Throwable $cause = null)
     {
         assert(is_string($authsource));
         assert(is_string($reason));
diff --git a/lib/SimpleSAML/Error/CriticalConfigurationError.php b/lib/SimpleSAML/Error/CriticalConfigurationError.php
index 8ddfd4f9f87fba3bd8997c4da7349150bec88ef8..da78e2ed7fcbdd9373551cbe9cb557c769cdb54d 100644
--- a/lib/SimpleSAML/Error/CriticalConfigurationError.php
+++ b/lib/SimpleSAML/Error/CriticalConfigurationError.php
@@ -7,6 +7,7 @@ namespace SimpleSAML\Error;
 use SimpleSAML\Configuration;
 use SimpleSAML\Logger;
 use SimpleSAML\Utils;
+use Throwable;
 
 /**
  * This exception represents a configuration error that we cannot recover from.
@@ -66,11 +67,11 @@ class CriticalConfigurationError extends ConfigurationError
 
 
     /**
-     * @param \Exception $exception
+     * @param \Throwable $exception
      *
      * @return CriticalConfigurationError
      */
-    public static function fromException(\Exception $exception)
+    public static function fromException(Throwable $exception): Exception
     {
         $reason = null;
         $file = null;
diff --git a/lib/SimpleSAML/Error/Error.php b/lib/SimpleSAML/Error/Error.php
index 563d373816971a40331a32c543477c1208eeb975..387cf8c5a2556125f2d59b263035589a0f8979ac 100644
--- a/lib/SimpleSAML/Error/Error.php
+++ b/lib/SimpleSAML/Error/Error.php
@@ -9,6 +9,7 @@ use SimpleSAML\Logger;
 use SimpleSAML\Session;
 use SimpleSAML\Utils;
 use SimpleSAML\XHTML\Template;
+use Throwable;
 
 /**
  * Class that wraps SimpleSAMLphp errors in exceptions.
@@ -74,11 +75,11 @@ class Error extends Exception
      * The error can either be given as a string, or as an array. If it is an array, the first element in the array
      * (with index 0), is the error code, while the other elements are replacements for the error text.
      *
-     * @param mixed     $errorCode One of the error codes defined in the errors dictionary.
-     * @param \Exception $cause The exception which caused this fatal error (if any). Optional.
-     * @param int|null  $httpCode The HTTP response code to use. Optional.
+     * @param mixed      $errorCode One of the error codes defined in the errors dictionary.
+     * @param \Throwable $cause The exception which caused this fatal error (if any). Optional.
+     * @param int|null   $httpCode The HTTP response code to use. Optional.
      */
-    public function __construct($errorCode, \Exception $cause = null, $httpCode = null)
+    public function __construct($errorCode, Throwable $cause = null, ?int $httpCode = null)
     {
         assert(is_string($errorCode) || is_array($errorCode));
 
diff --git a/lib/SimpleSAML/Error/Exception.php b/lib/SimpleSAML/Error/Exception.php
index df7ed1a52e5ce59dbd002498b81c44470a6a51ec..5177fd64d70514328a6cfede9bc9eaf4dcb30e38 100644
--- a/lib/SimpleSAML/Error/Exception.php
+++ b/lib/SimpleSAML/Error/Exception.php
@@ -6,6 +6,7 @@ namespace SimpleSAML\Error;
 
 use SimpleSAML\Configuration;
 use SimpleSAML\Logger;
+use Throwable;
 
 /**
  * Base class for SimpleSAMLphp Exceptions
@@ -45,9 +46,9 @@ class Exception extends \Exception
      *
      * @param string         $message Exception message
      * @param int            $code Error code
-     * @param \Exception|null $cause The cause of this exception.
+     * @param \Throwable|null $cause The cause of this exception.
      */
-    public function __construct($message, $code = 0, \Exception $cause = null)
+    public function __construct(string $message, int $code = 0, Throwable $cause = null)
     {
         assert(is_string($message));
         assert(is_int($code));
@@ -65,11 +66,11 @@ class Exception extends \Exception
     /**
      * Convert any exception into a \SimpleSAML\Error\Exception.
      *
-     * @param \Exception $e The exception.
+     * @param \Throwable $e The exception.
      *
      * @return Exception The new exception.
      */
-    public static function fromException(\Exception $e)
+    public static function fromException(Throwable $e): Exception
     {
         if ($e instanceof Exception) {
             return $e;
@@ -81,10 +82,10 @@ class Exception extends \Exception
     /**
      * Load the backtrace from the given exception.
      *
-     * @param \Exception $exception The exception we should fetch the backtrace from.
+     * @param \Throwable $exception The exception we should fetch the backtrace from.
      * @return void
      */
-    protected function initBacktrace(\Exception $exception)
+    protected function initBacktrace(Throwable $exception): void
     {
         $this->backtrace = [];
 
@@ -124,9 +125,9 @@ class Exception extends \Exception
     /**
      * Retrieve the cause of this exception.
      *
-     * @return Exception|null The cause of this exception.
+     * @return \Throwable|null The cause of this exception.
      */
-    public function getCause()
+    public function getCause(): ?Throwable
     {
         return $this->cause;
     }
diff --git a/lib/SimpleSAML/Error/UnserializableException.php b/lib/SimpleSAML/Error/UnserializableException.php
index dcee7b0a55b1a5f9171988cd03324c59ce1039de..287475590a77aac54307544e2e95dcb1a4b78a9a 100644
--- a/lib/SimpleSAML/Error/UnserializableException.php
+++ b/lib/SimpleSAML/Error/UnserializableException.php
@@ -4,6 +4,9 @@ declare(strict_types=1);
 
 namespace SimpleSAML\Error;
 
+use PDOException;
+use Throwable;
+
 /**
  * Class for saving normal exceptions for serialization.
  *
@@ -30,9 +33,9 @@ class UnserializableException extends Exception
     /**
      * Create a serializable exception representing an unserializable exception.
      *
-     * @param \Exception $original  The original exception.
+     * @param \Throwable $original  The original exception.
      */
-    public function __construct(\Exception $original)
+    public function __construct(Throwable $original)
     {
 
         $this->class = get_class($original);
diff --git a/lib/SimpleSAML/Error/UserAborted.php b/lib/SimpleSAML/Error/UserAborted.php
index 8d06695c6b0dfc104c450bae2fb174a653c4ea9a..e4926f636993f443555cca656b849f6bfb9763dd 100644
--- a/lib/SimpleSAML/Error/UserAborted.php
+++ b/lib/SimpleSAML/Error/UserAborted.php
@@ -4,6 +4,8 @@ declare(strict_types=1);
 
 namespace SimpleSAML\Error;
 
+use Throwable;
+
 /**
  * Exception indicating user aborting the authentication process.
  *
@@ -15,9 +17,9 @@ class UserAborted extends Error
     /**
      * Create the error
      *
-     * @param \Exception|null $cause  The exception that caused this error.
+     * @param \Throwable|null $cause  The exception that caused this error.
      */
-    public function __construct(\Exception $cause = null)
+    public function __construct(Throwable $cause = null)
     {
         parent::__construct('USERABORTED', $cause);
     }
diff --git a/lib/SimpleSAML/Utils/XML.php b/lib/SimpleSAML/Utils/XML.php
index 8c178fee12edb3c0c53697b6cd85e4ecc5cec13b..63e819f39a4b275e7f336792e257b92bfae411fd 100644
--- a/lib/SimpleSAML/Utils/XML.php
+++ b/lib/SimpleSAML/Utils/XML.php
@@ -59,12 +59,10 @@ class XML
         $enabled = Configuration::getInstance()->getBoolean('debug.validatexml', false);
 
         if (
-            !(in_array('validatexml', $debug, true) // implicitly enabled
-            || (array_key_exists('validatexml', $debug)
-            && $debug['validatexml'] === true)
-            // explicitly enabled
-            // TODO: deprecate this option and remove it in 2.0
-            || $enabled) // old 'debug.validatexml' configuration option
+            !(
+                in_array('validatexml', $debug, true)
+                || (array_key_exists('validatexml', $debug) && ($debug['validatexml'] === true))
+            )
         ) {
             // XML validation is disabled
             return;
diff --git a/modules/saml/lib/Error.php b/modules/saml/lib/Error.php
index c91c8e97d2e9d7cb3abe52807a94007f8f5c4c27..11a2645474e7caa1909642964e053d0cb27ef142 100644
--- a/modules/saml/lib/Error.php
+++ b/modules/saml/lib/Error.php
@@ -5,6 +5,7 @@ declare(strict_types=1);
 namespace SimpleSAML\Module\saml;
 
 use SAML2\Constants;
+use Throwable;
 
 /**
  * Class for representing a SAML 2 error.
@@ -44,14 +45,14 @@ class Error extends \SimpleSAML\Error\Exception
      * Can be NULL, in which case there is no second-level status code.
      * @param string|null $statusMessage  The status message.
      * Can be NULL, in which case there is no status message.
-     * @param \Exception|null $cause  The cause of this exception. Can be NULL.
+     * @param \Throwable|null $cause  The cause of this exception. Can be NULL.
      */
-    public function __construct($status, $subStatus = null, $statusMessage = null, \Exception $cause = null)
-    {
-        assert(is_string($status));
-        assert($subStatus === null || is_string($subStatus));
-        assert($statusMessage === null || is_string($statusMessage));
-
+    public function __construct(
+        string $status,
+        string $subStatus = null,
+        string $statusMessage = null,
+        Throwable $cause = null
+    ) {
         $st = self::shortStatus($status);
         if ($subStatus !== null) {
             $st .= '/' . self::shortStatus($subStatus);
@@ -106,10 +107,10 @@ class Error extends \SimpleSAML\Error\Exception
      * This function attempts to create a SAML2 error with the appropriate
      * status codes from an arbitrary exception.
      *
-     * @param \Exception $exception  The original exception.
-     * @return \SimpleSAML\Module\saml\Error  The new exception.
+     * @param \Throwable $exception  The original exception.
+     * @return \SimpleSAML\Error\Exception  The new exception.
      */
-    public static function fromException(\Exception $exception)
+    public static function fromException(Throwable $exception): \SimpleSAML\Error\Exception
     {
         if ($exception instanceof \SimpleSAML\Module\saml\Error) {
             // Return the original exception unchanged
diff --git a/modules/saml/lib/Error/NoAuthnContext.php b/modules/saml/lib/Error/NoAuthnContext.php
index 508da8e0ca4f0f347d060fa8c1f9ba32408e8a1d..100951540f2e882511a4c37e4f0568abdd893929 100644
--- a/modules/saml/lib/Error/NoAuthnContext.php
+++ b/modules/saml/lib/Error/NoAuthnContext.php
@@ -5,6 +5,7 @@ declare(strict_types=1);
 namespace SimpleSAML\Module\saml\Error;
 
 use SAML2\Constants;
+use Throwable;
 
 /**
  * A SAML error indicating that none of the requested Authentication Contexts can be used.
@@ -21,9 +22,9 @@ class NoAuthnContext extends \SimpleSAML\Module\saml\Error
      *   - \SAML2\Constants::STATUS_RESPONDER: in case the error is caused by this SAML responder.
      *   - \SAML2\Constants::STATUS_REQUESTER: in case the error is caused by the SAML requester.
      * @param string|null $message A short message explaining why this error happened.
-     * @param \Exception|null $cause An exception that caused this error.
+     * @param \Throwable|null $cause An exception that caused this error.
      */
-    public function __construct($responsible, $message = null, \Exception $cause = null)
+    public function __construct(string $responsible, string $message = null, Throwable $cause = null)
     {
         parent::__construct($responsible, Constants::STATUS_NO_AUTHN_CONTEXT, $message, $cause);
     }
diff --git a/modules/saml/lib/Error/NoAvailableIDP.php b/modules/saml/lib/Error/NoAvailableIDP.php
index f1c66ab4bbe7493ed2056f92163f202216a61c3c..5b6900092dd866e10fd2fcf32dd67852a36c7b14 100644
--- a/modules/saml/lib/Error/NoAvailableIDP.php
+++ b/modules/saml/lib/Error/NoAvailableIDP.php
@@ -5,6 +5,7 @@ declare(strict_types=1);
 namespace SimpleSAML\Module\saml\Error;
 
 use SAML2\Constants;
+use Throwable;
 
 /**
  * A SAML error indicating that none of the requested IdPs can be used.
@@ -21,9 +22,9 @@ class NoAvailableIDP extends \SimpleSAML\Module\saml\Error
      *   - \SAML2\Constants::STATUS_RESPONDER: in case the error is caused by this SAML responder.
      *   - \SAML2\Constants::STATUS_REQUESTER: in case the error is caused by the SAML requester.
      * @param string|null $message A short message explaining why this error happened.
-     * @param \Exception|null $cause An exception that caused this error.
+     * @param \Throwable|null $cause An exception that caused this error.
      */
-    public function __construct($responsible, $message = null, \Exception $cause = null)
+    public function __construct(string $responsible, string $message = null, Throwable $cause = null)
     {
         parent::__construct($responsible, Constants::STATUS_NO_AVAILABLE_IDP, $message, $cause);
     }
diff --git a/modules/saml/lib/Error/NoPassive.php b/modules/saml/lib/Error/NoPassive.php
index 3fc03e0499b61f9a93c64259cd2c10f5c573fb3b..f6e8f72514282cd633086adc11c7c7e99ffc11b4 100644
--- a/modules/saml/lib/Error/NoPassive.php
+++ b/modules/saml/lib/Error/NoPassive.php
@@ -5,6 +5,7 @@ declare(strict_types=1);
 namespace SimpleSAML\Module\saml\Error;
 
 use SAML2\Constants;
+use Throwable;
 
 /**
  * A SAML error indicating that passive authentication cannot be used.
@@ -21,9 +22,9 @@ class NoPassive extends \SimpleSAML\Module\saml\Error
      *   - \SAML2\Constants::STATUS_RESPONDER: in case the error is caused by this SAML responder.
      *   - \SAML2\Constants::STATUS_REQUESTER: in case the error is caused by the SAML requester.
      * @param string|null $message A short message explaining why this error happened.
-     * @param \Exception|null $cause An exception that caused this error.
+     * @param \Throwable|null $cause An exception that caused this error.
      */
-    public function __construct($responsible, $message = null, \Exception $cause = null)
+    public function __construct(string $responsible, string $message = null, Throwable $cause = null)
     {
         parent::__construct($responsible, Constants::STATUS_NO_PASSIVE, $message, $cause);
     }
diff --git a/modules/saml/lib/Error/NoSupportedIDP.php b/modules/saml/lib/Error/NoSupportedIDP.php
index 7806fb379e925e87301aa6cfae70743c8ad47c08..13fa5c391db99ff4f8a257df9c078e85ee555fc8 100644
--- a/modules/saml/lib/Error/NoSupportedIDP.php
+++ b/modules/saml/lib/Error/NoSupportedIDP.php
@@ -5,6 +5,7 @@ declare(strict_types=1);
 namespace SimpleSAML\Module\saml\Error;
 
 use SAML2\Constants;
+use Throwable;
 
 /**
  * A SAML error indicating that none of the IdPs requested are supported.
@@ -21,9 +22,9 @@ class NoSupportedIDP extends \SimpleSAML\Module\saml\Error
      *   - \SAML2\Constants::STATUS_RESPONDER: in case the error is caused by this SAML responder.
      *   - \SAML2\Constants::STATUS_REQUESTER: in case the error is caused by the SAML requester.
      * @param string|null $message A short message explaining why this error happened.
-     * @param \Exception|null $cause An exception that caused this error.
+     * @param \Throwable|null $cause An exception that caused this error.
      */
-    public function __construct($responsible, $message = null, \Exception $cause = null)
+    public function __construct(string $responsible, string $message = null, Throwable $cause = null)
     {
         parent::__construct($responsible, Constants::STATUS_NO_SUPPORTED_IDP, $message, $cause);
     }
diff --git a/modules/saml/lib/Error/ProxyCountExceeded.php b/modules/saml/lib/Error/ProxyCountExceeded.php
index 044aded1f9dd0d3ae5d2de0c3af8cd8abfb87f72..e078c803b03600827e585c1af7c4755e455917d9 100644
--- a/modules/saml/lib/Error/ProxyCountExceeded.php
+++ b/modules/saml/lib/Error/ProxyCountExceeded.php
@@ -5,6 +5,7 @@ declare(strict_types=1);
 namespace SimpleSAML\Module\saml\Error;
 
 use SAML2\Constants;
+use Throwable;
 
 /**
  * A SAML error indicating that the maximum amount of proxies traversed has been reached.
@@ -21,9 +22,9 @@ class ProxyCountExceeded extends \SimpleSAML\Module\saml\Error
      *   - \SAML2\Constants::STATUS_RESPONDER: in case the error is caused by this SAML responder.
      *   - \SAML2\Constants::STATUS_REQUESTER: in case the error is caused by the SAML requester.
      * @param string|null $message A short message explaining why this error happened.
-     * @param \Exception|null $cause An exception that caused this error.
+     * @param \Throwable|null $cause An exception that caused this error.
      */
-    public function __construct($responsible, $message = null, \Exception $cause = null)
+    public function __construct(string $responsible, string $message = null, Throwable $cause = null)
     {
         parent::__construct($responsible, Constants::STATUS_PROXY_COUNT_EXCEEDED, $message, $cause);
     }
diff --git a/www/_include.php b/www/_include.php
index afe9b6b39ec15722bcb3185e4308cda358b09d8b..fa3035c15942a56072b0967b1ef94786e24318a7 100644
--- a/www/_include.php
+++ b/www/_include.php
@@ -17,12 +17,8 @@ function SimpleSAML_exception_handler($exception)
         $e = new \SimpleSAML\Error\Error('UNHANDLEDEXCEPTION', $exception);
         $e->show();
     } elseif (class_exists('Error') && $exception instanceof \Error) {
-        $code = $exception->getCode();
-        $errno = ($code > 0) ? $code : E_ERROR;
-        $errstr = $exception->getMessage();
-        $errfile = $exception->getFile();
-        $errline = $exception->getLine();
-        SimpleSAML_error_handler($errno, $errstr, $errfile, $errline);
+        $e = new \SimpleSAML\Error\Error('UNHANDLEDEXCEPTION', $exception);
+        $e->show();
     }
 }