1 files changed, 6 insertions, 3 deletions
diff --git a/Lib/pdb.py b/Lib/pdb.py
index e507a9b..0f791d7 100755
--- a/Lib/pdb.py
+++ b/Lib/pdb.py
@@ -392,9 +392,12 @@ class Pdb(bdb.Bdb, cmd.Cmd):
             self.tb_lineno[tb.tb_frame] = lineno
             tb = tb.tb_next
         self.curframe = self.stack[self.curindex][0]
-        # The f_locals dictionary is updated from the actual frame
-        # locals whenever the .f_locals accessor is called, so we
-        # cache it here to ensure that modifications are not overwritten.
+        # The f_locals dictionary used to be updated from the actual frame
+        # locals whenever the .f_locals accessor was called, so it was
+        # cached here to ensure that modifications were not overwritten. While
+        # the caching is no longer required now that f_locals is a direct proxy
+        # on optimized frames, it's also harmless, so the code structure has
+        # been left unchanged.
         self.curframe_locals = self.curframe.f_locals
         self.set_convenience_variable(self.curframe, '_frame', self.curframe)