diff --git a/src/library/class_instance_resolution.cpp b/src/library/class_instance_resolution.cpp
index 1255920b8c..8275f4ee40 100644
--- a/src/library/class_instance_resolution.cpp
+++ b/src/library/class_instance_resolution.cpp
@@ -4,6 +4,7 @@ Released under Apache 2.0 license as described in the file LICENSE.
 
 Author: Leonardo de Moura
 */
+#include <vector>
 #include "util/lbool.h"
 #include "util/interrupt.h"
 #include "util/sexpr/option_declarations.h"
diff --git a/src/library/init_module.cpp b/src/library/init_module.cpp
index 235830acf4..ed0abd3df1 100644
--- a/src/library/init_module.cpp
+++ b/src/library/init_module.cpp
@@ -37,7 +37,6 @@ Author: Leonardo de Moura
 #include "library/abbreviation.h"
 #include "library/relation_manager.h"
 #include "library/user_recursors.h"
-#include "library/class_instance_resolution.h"
 #include "library/composition_manager.h"
 #include "library/noncomputable.h"
 #include "library/aux_recursors.h"