Index: src/InitTweak/FixInitNew.cpp
===================================================================
--- src/InitTweak/FixInitNew.cpp	(revision 8603c103d67729d4e4cec233b1b6f1f2a5e89d90)
+++ src/InitTweak/FixInitNew.cpp	(revision 397c43920f925c1b88953d821a0a5bef98a15750)
@@ -107,6 +107,6 @@
 	private:
 		/// hack to implement WithTypeSubstitution while conforming to mutation safety.
-		ast::TypeSubstitution * env;
-		bool                    envModified;
+		ast::TypeSubstitution * env         = nullptr;
+		bool                    envModified = false;
 	};