diff --git a/pjsip/include/pjsip-simple/evsub.h b/pjsip/include/pjsip-simple/evsub.h
index 1ffffbe..25ad489 100644
--- a/pjsip/include/pjsip-simple/evsub.h
+++ b/pjsip/include/pjsip-simple/evsub.h
@@ -214,12 +214,12 @@
 /**
  * SUBSCRIBE method constant.
  */
-PJ_DECL(const pjsip_method*) pjsip_get_subscribe_method();
+PJ_DECL(const pjsip_method*) pjsip_get_subscribe_method(void);
 
 /**
  * NOTIFY method constant.
  */
-PJ_DECL(const pjsip_method*) pjsip_get_notify_method();
+PJ_DECL(const pjsip_method*) pjsip_get_notify_method(void);
 
 
 /**
diff --git a/pjsip/include/pjsip-ua/sip_xfer.h b/pjsip/include/pjsip-ua/sip_xfer.h
index 05614c2..ef2611a 100644
--- a/pjsip/include/pjsip-ua/sip_xfer.h
+++ b/pjsip/include/pjsip-ua/sip_xfer.h
@@ -65,7 +65,7 @@
 PJ_DECL_DATA(const pjsip_method) pjsip_refer_method;
 
 /** Get REFER method constant */
-PJ_DECL(const pjsip_method*) pjsip_get_refer_method();
+PJ_DECL(const pjsip_method*) pjsip_get_refer_method(void);
 
 
 /**