diff --git a/Lib/StringIO.py b/Lib/StringIO.py
index 715e71e76f0..c9794872637 100644
--- a/Lib/StringIO.py
+++ b/Lib/StringIO.py
@@ -33,6 +33,7 @@ class StringIO:
 		self.buf = buf
 		self.pos = 0
 		self.closed = 0
+		self.softspace = 0
 	def close(self):
 		if not self.closed:
 			self.closed = 1