diff --git a/loader/wine/winbase.h b/loader/wine/winbase.h
index ee12af3632..8746da891d 100644
--- a/loader/wine/winbase.h
+++ b/loader/wine/winbase.h
@@ -1495,7 +1495,7 @@ VOID        WINAPI UnMapLS(SEGPTR);
 WIN_BOOL      WINAPI UnlockFile(HANDLE,DWORD,DWORD,DWORD,DWORD);
 WIN_BOOL      WINAPI UnmapViewOfFile(LPVOID);
 LPVOID      WINAPI VirtualAlloc(LPVOID,DWORD,DWORD,DWORD);
-WIN_BOOL      WINAPI VirtualFree(LPVOID,DWORD,DWORD);
+WIN_BOOL      WINAPI VirtualFree(LPVOID,SIZE_T,DWORD);
 WIN_BOOL      WINAPI VirtualLock(LPVOID,DWORD);
 WIN_BOOL      WINAPI VirtualProtect(LPVOID,DWORD,DWORD,LPDWORD);
 WIN_BOOL      WINAPI VirtualProtectEx(HANDLE,LPVOID,DWORD,DWORD,LPDWORD);