diff --git a/dlls/setupapi/tests/devinst.c b/dlls/setupapi/tests/devinst.c
index c75d2f74ba6..a4f80ba5019 100644
--- a/dlls/setupapi/tests/devinst.c
+++ b/dlls/setupapi/tests/devinst.c
@@ -1133,7 +1133,7 @@ static void testRegisterAndGetDetail(void)
     }
 }
 
-static void testDeviceRegistryPropertyA()
+static void testDeviceRegistryPropertyA(void)
 {
     HDEVINFO set;
     SP_DEVINFO_DATA devInfo = { sizeof(SP_DEVINFO_DATA), { 0 } };
@@ -1237,7 +1237,7 @@ static void testDeviceRegistryPropertyA()
     }
 }
 
-static void testDeviceRegistryPropertyW()
+static void testDeviceRegistryPropertyW(void)
 {
     HDEVINFO set;
     SP_DEVINFO_DATA devInfo = { sizeof(SP_DEVINFO_DATA), { 0 } };