Xcode 9 beta issue with LIBCXXABI_NORETURN

[MikeWeller]

Building our app with Xcode 9 and the latest iOS 11 beta SDK we are getting errors with the use of LIBCXXABI_NORETURN:

.../HockeySDK-iOS/Classes/BITCrashCXXExceptionHandler.mm:61:17: error: variable has incomplete type 'void'
extern "C" void LIBCXXABI_NORETURN __cxa_throw(void *exception_object, std::type_info *tinfo, void (*dest)(void *))
                ^
.../HockeySDK-iOS/Classes/BITCrashCXXExceptionHandler.mm:61:35: error: expected ';' after top level declarator
extern "C" void LIBCXXABI_NORETURN __cxa_throw(void *exception_object, std::type_info *tinfo, void (*dest)(void *))
                                  ^
                                  ;

We've fixed this temporarily by replacing LIBCXXABI_NORETURN with __attribute__((noreturn)) which I'm assuming is what this used to be anyway. Not sure if LIBCXXABI_NORETURN just needs an include (I haven't looked into this too much yet) but perhaps it's better to define your own macro for this anyway, or just use __attribute__((noreturn)) directly, since this might technically be a private macro of libc++?

[lumaxis]

This was fixed by #421 ✌️