Use weakrefs where absolutely safe to do so, in order to reduce the number of circular references. Replace unnecessary OrderedDict with a regular dict.

PiperOrigin-RevId: 213982097

1 files changed, 5 insertions, 1 deletions

diff --git a/tensorflow/python/autograph/pyct/static_analysis/activity.py b/tensorflow/python/autograph/pyct/static_analysis/activity.py
index 9cb5991322..086eda7574 100644
--- a/tensorflow/python/autograph/pyct/static_analysis/activity.py
+++ b/tensorflow/python/autograph/pyct/static_analysis/activity.py
@@ -22,6 +22,7 @@ from __future__ import division
 from __future__ import print_function
 
 import copy
+import weakref
 
 import gast
 
@@ -126,7 +127,10 @@ class Scope(object):
       self.parent.mark_read(name)
 
   def mark_param(self, name, owner):
-    self.params[name] = owner
+    # Assumption: all AST nodes have the same life span. This lets us use
+    # a weak reference to mark the connection between a symbol node and the
+    # function node whose argument that symbol is.
+    self.params[name] = weakref.ref(owner)
 
   def mark_creation(self, name, writes_create_symbol=False):
     """Mark a qualified name as created."""