Fixed bug 3517 - Compiler warnings with gcc -Wstrict-prototypes

felix

Compiling even a simple SDL2 'hello world' program with gcc -Wstrict-prototypes (GCC 6.2.1) results in warnings like:

/usr/include/SDL2/SDL_gamecontroller.h:143:1: attention : function declaration isn't a prototype [-Wstrict-prototypes]
 extern DECLSPEC int SDLCALL SDL_GameControllerNumMappings();
 ^~~~~~

It seems there is a missing 'void' between the parentheses.

src/core/windows/SDL_windows.c

@@ -115,7 +115,7 @@ IsWindowsVersionOrGreater(WORD wMajorVersion, WORD wMinorVersion, WORD wServiceP
 }
 #endif
 
-BOOL WIN_IsWindowsVistaOrGreater()
+BOOL WIN_IsWindowsVistaOrGreater(void)
 {
 #ifdef __WINRT__
     return TRUE;

src/core/windows/SDL_windows.h

@@ -57,7 +57,7 @@ extern HRESULT WIN_CoInitialize(void);
 extern void WIN_CoUninitialize(void);
 
 /* Returns SDL_TRUE if we're running on Windows Vista and newer */
-extern BOOL WIN_IsWindowsVistaOrGreater();
+extern BOOL WIN_IsWindowsVistaOrGreater(void);
 
 /* You need to SDL_free() the result of this call. */
 extern char *WIN_LookupAudioDeviceName(const WCHAR *name, const GUID *guid);