diff --git a/xcb.h b/xcb.h
index d55932c..5151915 100644
--- a/xcb.h
+++ b/xcb.h
@@ -11,17 +11,17 @@ char *get_atom_name(xcb_connection_t *conn, xcb_atom_t atom);
 const char *xcb_error(const xcb_generic_error_t *error);
 
 /* Cached atoms */
-xcb_atom_t UTF8_STRING;
-xcb_atom_t _NET_WM_PID;
-xcb_atom_t _NET_WM_WINDOW_TYPE;
-xcb_atom_t _NET_WM_WINDOW_TYPE_DOCK;
-xcb_atom_t _NET_WM_STATE;
-xcb_atom_t _NET_WM_STATE_ABOVE;
-xcb_atom_t _NET_WM_STATE_STICKY;
-xcb_atom_t _NET_WM_DESKTOP;
-xcb_atom_t _NET_WM_STRUT;
-xcb_atom_t _NET_WM_STRUT_PARTIAL;
-xcb_atom_t _NET_ACTIVE_WINDOW;
-xcb_atom_t _NET_CURRENT_DESKTOP;
-xcb_atom_t _NET_WM_VISIBLE_NAME;
-xcb_atom_t _NET_WM_NAME;
+extern xcb_atom_t UTF8_STRING;
+extern xcb_atom_t _NET_WM_PID;
+extern xcb_atom_t _NET_WM_WINDOW_TYPE;
+extern xcb_atom_t _NET_WM_WINDOW_TYPE_DOCK;
+extern xcb_atom_t _NET_WM_STATE;
+extern xcb_atom_t _NET_WM_STATE_ABOVE;
+extern xcb_atom_t _NET_WM_STATE_STICKY;
+extern xcb_atom_t _NET_WM_DESKTOP;
+extern xcb_atom_t _NET_WM_STRUT;
+extern xcb_atom_t _NET_WM_STRUT_PARTIAL;
+extern xcb_atom_t _NET_ACTIVE_WINDOW;
+extern xcb_atom_t _NET_CURRENT_DESKTOP;
+extern xcb_atom_t _NET_WM_VISIBLE_NAME;
+extern xcb_atom_t _NET_WM_NAME;