diff --git a/include/pocketpy/common/any.hpp b/include/pocketpy/common/any.hpp
index 5b14b533..1e9ad99d 100644
--- a/include/pocketpy/common/any.hpp
+++ b/include/pocketpy/common/any.hpp
@@ -5,6 +5,7 @@
 #include <typeindex>
 #include <cassert>
 #include <utility>
+#include <cstdlib>
 #include <cstring>
 
 namespace pkpy {
diff --git a/include/pocketpy/common/vector.hpp b/include/pocketpy/common/vector.hpp
index 5ca72a60..afea205b 100644
--- a/include/pocketpy/common/vector.hpp
+++ b/include/pocketpy/common/vector.hpp
@@ -3,6 +3,7 @@
 #include "pocketpy/common/traits.hpp"
 #include "pocketpy/common/types.hpp"
 
+#include <cstdlib>
 #include <cstring>
 #include <cassert>
 #include <memory>
diff --git a/include/pocketpy/objects/base.hpp b/include/pocketpy/objects/base.hpp
index ca3a8b04..1dc457ba 100644
--- a/include/pocketpy/objects/base.hpp
+++ b/include/pocketpy/objects/base.hpp
@@ -5,6 +5,7 @@
 
 #include <cstdint>
 #include <cassert>
+#include <cstdlib>
 #include <cstring>
 
 namespace pkpy{
diff --git a/src/common/memorypool.cpp b/src/common/memorypool.cpp
index 361af38e..e5137af0 100644
--- a/src/common/memorypool.cpp
+++ b/src/common/memorypool.cpp
@@ -2,6 +2,7 @@
 #include "pocketpy/common/gil.hpp"
 #include "pocketpy/config.h"
 
+#include <cstdlib>
 #include <cstring>
 #include <stdexcept>