Index: tests/phpunit/tests/general/document-title.php
===================================================================
--- tests/phpunit/tests/general/document-title.php	(revision 36137)
+++ tests/phpunit/tests/general/document-title.php	(working copy)
@@ -243,4 +243,25 @@
 	function _change_title_separator( $sep ) {
 		return '%%';
 	}
+
+	/**
+	 * @ticket 34879
+	 */
+	function test_wp_title_t_sep_typo() {
+		update_option( 'show_on_front', 'page' );
+
+		$this->go_to( '/' );
+
+		global $wp_query;
+		$wp_query->queried_object = $wp_query->post;
+		$wp_query->queried_object_id = (int) $wp_query->queried_object->ID;
+
+		$old_title = $wp_query->post->post_title;
+		$wp_query->post->post_title = 'test%WP_TITLE_SEP%title';
+
+		$this->assertEquals( ' » test » title', wp_title( '»', false ) );
+
+		$wp_query->post->post_title = $old_title;
+		update_option( 'show_on_front', 'posts' );
+	}
 }
Index: src/wp-includes/general-template.php
===================================================================
--- src/wp-includes/general-template.php	(revision 36137)
+++ src/wp-includes/general-template.php	(working copy)
@@ -995,7 +995,7 @@
 	$search   = get_query_var( 's' );
 	$title    = '';
 
-	$t_sep = '%WP_TITILE_SEP%'; // Temporary separator, for accurate flipping, if necessary
+	$t_sep = '%WP_TITLE_SEP%'; // Temporary separator, for accurate flipping, if necessary
 
 	// If there is a post
 	if ( is_single() || ( is_home() && ! is_front_page() ) || ( is_page() && ! is_front_page() ) ) {