diff --git a/compiler/optimizing/loop_optimization.h b/compiler/optimizing/loop_optimization.h
index 0535c74..6dd778b 100644
--- a/compiler/optimizing/loop_optimization.h
+++ b/compiler/optimizing/loop_optimization.h
@@ -17,6 +17,7 @@
 #ifndef ART_COMPILER_OPTIMIZING_LOOP_OPTIMIZATION_H_
 #define ART_COMPILER_OPTIMIZING_LOOP_OPTIMIZATION_H_
 
+#include "base/macros.h"
 #include "base/scoped_arena_allocator.h"
 #include "base/scoped_arena_containers.h"
 #include "induction_var_range.h"
@@ -25,7 +26,7 @@
 #include "optimization.h"
 #include "superblock_cloner.h"
 
-namespace art {
+namespace art HIDDEN {
 
 class CompilerOptions;
 class ArchNoOptsLoopHelper;