diff --git a/wp-includes/compat.php b/wp-includes/compat.php
index a0976c1ef2..d46b0e5230 100644
--- a/wp-includes/compat.php
+++ b/wp-includes/compat.php
@@ -503,7 +503,7 @@ if ( ! function_exists( 'is_countable' ) ) {
 	 * Polyfill for is_countable() function added in PHP 7.3.
 	 *
 	 * Verify that the content of a variable is an array or an object
-	 * implementing Countable.
+	 * implementing the Countable interface.
 	 *
 	 * @since 4.9.6
 	 *
@@ -515,3 +515,21 @@ if ( ! function_exists( 'is_countable' ) ) {
 		return ( is_array( $var ) || $var instanceof Countable );
 	}
 }
+
+if ( ! function_exists( 'is_iterable' ) ) {
+	/**
+	 * Polyfill for is_iterable() function added in PHP 7.1.
+	 *
+	 * Verify that the content of a variable is an array or an object
+	 * implementing the Traversable interface.
+	 *
+	 * @since 4.9.6
+	 *
+	 * @param mixed $var The value to check.
+	 *
+	 * @return bool True if `$var` is iterable, false otherwise.
+	 */
+	function is_iterable( $var ) {
+		return ( is_array( $var ) || $var instanceof Traversable );
+	}
+}
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 082665c84a..4c334e8664 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.9.6-alpha-43035';
+$wp_version = '4.9.6-alpha-43037';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.