diff --git a/build.hpp b/build.hpp
index 04b6b85..8d1bc4e 100644
--- a/build.hpp
+++ b/build.hpp
@@ -334,6 +334,7 @@ bool compile_obj_dir()
     command.push_back(i.string());
   }
 
+  command.push_back(opt_flags);
   command.push_back("-o");
   command.push_back(BUILD_FILE.string());