diff --git a/Formula/giblib.rb b/Formula/giblib.rb
index c2b53f6aa7..93672cdafa 100644
--- a/Formula/giblib.rb
+++ b/Formula/giblib.rb
@@ -6,9 +6,14 @@ class Giblib < Formula
   sha1 '342e6f7882c67d2277e1765299e1be5078329ab0'
 
   depends_on 'imlib2' => :build
+  depends_on :x11 # includes <X11/Xlib.h>
 
   def install
     system "./configure", "--prefix=#{prefix}"
     system "make install"
   end
+
+  def test
+    system "#{bin}/giblib-config", "--version"
+  end
 end