gistfile1.php

// The following goes in functions.php
add_action( 'woocommerce_after_shop_loop_item_title', 'woocommerce_template_loop_stock', 10);
function woocommerce_template_loop_stock() {
	global $product;
 		if ( ! $product->managing_stock() && ! $product->is_in_stock() )
 		echo '<p class="stock out-of-stock">out-of-stock</p>';
}