diff --git a/clang/lib/Analysis/FlowSensitive/Transfer.cpp b/clang/lib/Analysis/FlowSensitive/Transfer.cpp
--- a/clang/lib/Analysis/FlowSensitive/Transfer.cpp
+++ b/clang/lib/Analysis/FlowSensitive/Transfer.cpp
@@ -129,6 +129,8 @@
   return &UnpackedVal;
 }
 
+namespace {
+
 class TransferVisitor : public ConstStmtVisitor<TransferVisitor> {
 public:
   TransferVisitor(const StmtToEnvMap &StmtToEnv, Environment &Env)
@@ -874,6 +876,8 @@
   Environment &Env;
 };
 
+} // namespace
+
 void transfer(const StmtToEnvMap &StmtToEnv, const Stmt &S, Environment &Env) {
   TransferVisitor(StmtToEnv, Env).Visit(&S);
 }