diff --git a/include/msgpack/gcc_atomic.hpp b/include/msgpack/gcc_atomic.hpp
index ace1d89d..c21e5d99 100644
--- a/include/msgpack/gcc_atomic.hpp
+++ b/include/msgpack/gcc_atomic.hpp
@@ -11,7 +11,7 @@
 #ifndef MSGPACK_GCC_ATOMIC_HPP
 #define MSGPACK_GCC_ATOMIC_HPP
 
-#ifdef ENABLE_GCC_CXX_ATOMIC
+#ifdef MSGPACK_ENABLE_GCC_CXX_ATOMIC
 #if defined(__GNUC__) && ((__GNUC__*10 + __GNUC_MINOR__) < 41)
 
 #include "msgpack/gcc_atomic.h"
@@ -28,6 +28,6 @@ int _msgpack_sync_incr_and_fetch(volatile _msgpack_atomic_counter_t* ptr)
 }
 
 #endif // old gcc workaround
-#endif // ENABLE_GCC_CXX_ATOMIC
+#endif // MSGPACK_ENABLE_GCC_CXX_ATOMIC
 
 #endif /* gcc_atomic.hpp */
diff --git a/include/msgpack/sysdep.h b/include/msgpack/sysdep.h
index b1ee1488..2884d833 100644
--- a/include/msgpack/sysdep.h
+++ b/include/msgpack/sysdep.h
@@ -51,9 +51,9 @@
 #elif defined(__GNUC__) && ((__GNUC__*10 + __GNUC_MINOR__) < 41)
 
 #   if defined(__cplusplus)
-#       define _msgpack_atomic_counter_header "gcc_atomic.hpp"
+#       define _msgpack_atomic_counter_header "msgpack/gcc_atomic.hpp"
 #   else
-#       define _msgpack_atomic_counter_header "gcc_atomic.h"
+#       define _msgpack_atomic_counter_header "msgpack/gcc_atomic.h"
 #   endif
 
 #else