Functions with no paramters must be (void).

dlls/msvcrt/msvcrt.h

@@ -65,10 +65,10 @@ typedef long MSVCRT_clock_t;
 typedef long MSVCRT_time_t;
 typedef __int64 MSVCRT_fpos_t;
 
-typedef void (*MSVCRT_terminate_handler)();
-typedef void (*MSVCRT_terminate_function)();
-typedef void (*MSVCRT_unexpected_handler)();
-typedef void (*MSVCRT_unexpected_function)();
+typedef void (*MSVCRT_terminate_handler)(void);
+typedef void (*MSVCRT_terminate_function)(void);
+typedef void (*MSVCRT_unexpected_handler)(void);
+typedef void (*MSVCRT_unexpected_function)(void);
 typedef void (*MSVCRT__se_translator_function)(unsigned int code, struct _EXCEPTION_POINTERS *info);
 typedef void (*MSVCRT__beginthread_start_routine_t)(void *);
 typedef unsigned int (__stdcall *MSVCRT__beginthreadex_start_routine_t)(void *);

dlls/ntdll/relay.c

@@ -266,8 +266,8 @@ typedef struct tagSNOOP_RETURNENTRIES {
 
 #include "poppack.h"
 
-extern void WINAPI SNOOP_Entry();
-extern void WINAPI SNOOP_Return();
+extern void WINAPI SNOOP_Entry(void);
+extern void WINAPI SNOOP_Return(void);
 
 static SNOOP_DLL *firstdll;
 static SNOOP_RETURNENTRIES *firstrets;

dlls/ole32/ole16.c

@@ -173,7 +173,7 @@ LPVOID IMalloc16_fnHeapMinimize(IMalloc16* iface) {
  * IMalloc16_Constructor [VTABLE]
  */
 LPMALLOC16
-IMalloc16_Constructor()
+IMalloc16_Constructor(void)
 {
     static IMalloc16Vtbl vt16;
     static SEGPTR msegvt16;