ddraw: Don't enumerate surfaces without references.

dlls/ddraw/ddraw.c

diff --git a/dlls/ddraw/ddraw.c b/dlls/ddraw/ddraw.c
index 03d8b1c..b344b81 100644
--- a/dlls/ddraw/ddraw.c
+++ b/dlls/ddraw/ddraw.c
@@ -3422,6 +3422,13 @@
     LIST_FOR_EACH_SAFE(entry, entry2, &This->surface_list)
     {
         surf = LIST_ENTRY(entry, IDirectDrawSurfaceImpl, surface_list_entry);
+
+        if (!surf->iface_count)
+        {
+            WARN("Not enumerating surface %p because it doesn't have any references.\n", surf);
+            continue;
+        }
+
         if (all || (nomatch != ddraw_match_surface_desc(DDSD, &surf->surface_desc)))
         {
             TRACE("Enumerating surface %p.\n", surf);