diff --git a/Source/xlib/XGGState.m b/Source/xlib/XGGState.m
index 85a9301..f3f3f6c 100644
--- a/Source/xlib/XGGState.m
+++ b/Source/xlib/XGGState.m
@@ -1423,6 +1423,13 @@ typedef enum {
   char dash_list[size];
   int i;
 
+  if ((pat == NULL) || (size == 0))
+    {
+      gcv.line_style = LineSolid;
+      [self setGCValues: gcv withMask: GCLineStyle];
+      return;
+    }
+
   gcv.line_style = LineOnOffDash;
   [self setGCValues: gcv withMask: GCLineStyle];