diff --git a/cardenc/pycard.cc b/cardenc/pycard.cc
index 4ae27fe..5941d0a 100644
--- a/cardenc/pycard.cc
+++ b/cardenc/pycard.cc
@@ -11,6 +11,7 @@
 #include <setjmp.h>
 #include <signal.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <Python.h>

 #include "card.hh"
@@ -122,8 +123,14 @@ static struct PyModuleDef module_def = {
 	NULL,              /* m_free */
 };

+static volatile int *_dummy_malloc;
+
 PyMODINIT_FUNC PyInit_pycard(void)
 {
+	_dummy_malloc = (int *)malloc(sizeof(int));
+	*_dummy_malloc = 1;
+	free((void *)_dummy_malloc);
+
 	PyObject *m = PyModule_Create(&module_def);

 	if (m == NULL)
diff --git a/solvers/pysolvers.cc b/solvers/pysolvers.cc
index 7066cb4..6b4d7de 100644
--- a/solvers/pysolvers.cc
+++ b/solvers/pysolvers.cc
@@ -15,6 +15,7 @@
 #include <setjmp.h>
 #include <signal.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <vector>

 #ifdef WITH_CADICAL
@@ -493,8 +494,14 @@ static struct PyModuleDef module_def = {
 	NULL,              /* m_free */
 };

+static volatile int *_dummy_malloc;
+
 PyMODINIT_FUNC PyInit_pysolvers(void)
 {
+	_dummy_malloc = (int *)malloc(sizeof(int));
+	*_dummy_malloc = 1;
+	free((void *)_dummy_malloc);
+
 	PyObject *m = PyModule_Create(&module_def);

 	if (m == NULL)