conservative fix for empty switch statements

Cython/Compiler/Nodes.py

@@ -3469,6 +3469,7 @@ class SwitchStatNode(StatNode):
         if self.else_clause is not None:
             code.putln("default:")
             self.else_clause.generate_execution_code(code)
+            code.putln("break;")
         code.putln("}")
 
     def annotate(self, code):

tests/run/switch.pyx

@@ -89,6 +89,9 @@ __doc__ = u"""
 1
 >>> switch_off(2)
 0
+
+>>> switch_pass(1)
+1
 """
 
 def switch_simple_py(x):
@@ -173,3 +176,12 @@ def switch_off(int x):
     else:
         return 0
     return -1
+
+def switch_pass(int x):
+    if x == 1:
+        pass
+    elif x == 2:
+        pass
+    else:
+        pass
+    return x