diff --git a/src/if_python.c b/src/if_python.c
index c6b14fe..af5d6c0 100644
--- a/src/if_python.c
+++ b/src/if_python.c
@@ -317,7 +317,7 @@
  */
 static int(*dll_PyArg_Parse)(PyObject *, char *, ...);
 static int(*dll_PyArg_ParseTuple)(PyObject *, char *, ...);
-static int(*dll_PyMem_Free)(void *);
+static void(*dll_PyMem_Free)(void *);
 static void* (*dll_PyMem_Malloc)(size_t);
 static int(*dll_PyDict_SetItemString)(PyObject *dp, char *key, PyObject *item);
 static int(*dll_PyErr_BadArgument)(void);