Issue #1645156 by attiks: Fixed URL generation only works on port 80.

core/modules/language/language.negotiation.inc

@@ -383,6 +383,15 @@ function language_url_rewrite_url(&$path, &$options) {
           $url_scheme = ($is_https) ? 'https://' : 'http://';
           $options['absolute'] = TRUE;
           $options['base_url'] = $url_scheme . $domains[$options['language']->langcode];
+
+          // HTTP_HOST will optionally contain the port. Preserve that for
+          // the domain of the target language as well.
+          $http_host = $_SERVER['HTTP_HOST'];
+          if (strpos($http_host, ':') !== FALSE) {
+            $http_host_tmp = explode(':', $http_host);
+            $options['base_url'] .= ':' . end($http_host_tmp);
+          }
+
           if (isset($options['https']) && variable_get('https', FALSE)) {
             if ($options['https'] === TRUE) {
               $options['base_url'] = str_replace('http://', 'https://', $options['base_url']);

core/modules/language/lib/Drupal/language/Tests/LanguageUrlRewritingTest.php

@@ -79,4 +79,34 @@ private function checkUrl($language, $message1, $message2) {
     $this->drupalGet("$prefix/$path");
     $this->assertResponse(404, $message2);
   }
+
+  /**
+   * Check URL rewriting when using a domain name and a non-standard port.
+   */
+  function testDomainNameNegotiationPort() {
+    $language_domain = 'example.fr';
+    $edit = array(
+      'language_negotiation_url_part' => 1,
+      'domain[fr]' => $language_domain
+    );
+    $this->drupalPost('admin/config/regional/language/detection/url', $edit, t('Save configuration'));
+
+    // Enable domain configuration.
+    variable_set('language_negotiation_url_part', LANGUAGE_NEGOTIATION_URL_DOMAIN);
+
+    // Reset static caching.
+    drupal_static_reset('language_list');
+    drupal_static_reset('language_url_outbound_alter');
+    drupal_static_reset('language_url_rewrite_url');
+
+    // Fake a different port.
+    $_SERVER['HTTP_HOST'] .= ':88';
+
+    // Create an absolute French link.
+    $language = language_load('fr');
+    $url = url('', array('absolute' => TRUE, 'language' => $language));
+
+    $this->assertTrue(strcmp($url, 'http://example.fr:88/') == 0, 'The right port is used.');
+  }
+
 }