diff --git a/Modules/mpzmodule.c b/Modules/mpzmodule.c
index 4299f45..e1fd7bf 100644
--- a/Modules/mpzmodule.c
+++ b/Modules/mpzmodule.c
@@ -1819,7 +1819,7 @@
 
 /* Initialize this module. */
 
-void
+DL_EXPORT(void)
 initmpz()
 {
 	PyObject *module;