fix refnanny for closure variable assignments

Cython/Compiler/ExprNodes.py

@@ -1206,6 +1206,8 @@ class NameNode(AtomicExprNode):
                 if entry.is_cglobal:
                     code.put_giveref(rhs.py_result())
             code.putln('%s = %s;' % (self.result(), rhs.result_as(self.ctype())))
+            if self.type.is_pyobject and self.entry.in_closure:
+                code.put_giveref(self.result())
             if debug_disposal_code:
                 print("NameNode.generate_assignment_code:")
                 print("...generating post-assignment code for %s" % rhs)

tests/run/closures_T82.pyx

@@ -73,13 +73,13 @@ def inner_override(a,b):
 def reassign(x):
     def f(a):
         return a+x
-    x = 1 # currently lacks a GIVEREF()
+    x = 1
     return f
 
 def reassign_int(x):
     def f(int a):
         return a+x
-    x = 1 # currently lacks a GIVEREF()
+    x = 1
     return f
 
 def reassign_int_int(int x):
@@ -100,15 +100,15 @@ def cy_twofuncs(x):
 
 def more_inner_funcs(x):
     # pretty ugly segfault
-    def f(a): # this lacks a GIVEREF()
+    def f(a):
         def g(b):
             return a+b+x
         return g
-    def g(b): # this lacks a GIVEREF()
+    def g(b):
         def f(a):
             return a+b+x
         return f
-    def h(b): # this lacks a GIVEREF()
+    def h(b):
         def f(a):
             return a+b+x
         return f