diff --git a/deco.h b/deco.h
index f9ed7d4d7..bf305b93b 100644
--- a/deco.h
+++ b/deco.h
@@ -9,4 +9,8 @@ extern "C" {
 
   extern double buehlmann_N2_t_halflife[];
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif