diff --git a/cpp/CMakeLists.txt b/cpp/CMakeLists.txt
index 27e4680cc..969db99ea 100644
--- a/cpp/CMakeLists.txt
+++ b/cpp/CMakeLists.txt
@@ -421,7 +421,7 @@ if (NOT WIN32)
   add_definitions ("-Wall -Werror")
 endif ()
 
-include_directories ("src")
+include_directories (BEFORE "src")
 
 #----------------------------------------------------------------
 # Collate dependencies