Add error check requiring non-zero area pin layouts.

compiler/base/pin_layout.py

@@ -19,6 +19,10 @@ class pin_layout:
             self.rect = [vector(rect[0]),vector(rect[1])]
         # snap the rect to the grid
         self.rect = [x.snap_to_grid() for x in self.rect]
+
+        debug.check(self.width()>0,"Zero width pin.")
+        debug.check(self.height()>0,"Zero height pin.")
+        
         # if it's a layer number look up the layer name. this assumes a unique layer number.
         if type(layer_name_num)==int:
             self.layer = list(layer.keys())[list(layer.values()).index(layer_name_num)]