More thread return fixes

src/gos/gos.h

@@ -69,6 +69,16 @@
 	 */
 	#define DECLARE_THREAD_STACK(name, sz)			uint8_t name[sz];
 
+	/*
+	 * @brief	Return from a thread
+	 *
+	 * @details	Some underlying operating systems allow to return a value from a thread while others don't.
+	 *			For systems that don't allow to return a value from a thread function this call is simply ignored.
+	 *
+	 * @param[in] reval		The value which should be returned
+	 */
+	#define THREAD_RETURN(retval)					return retval
+
 	/**
 	 * @name	Various platform (and operating system) constants
 	 * @note	Your platform may use slightly different definitions to these

src/gos/gos_freertos.h

@@ -63,6 +63,7 @@ typedef portBASE_TYPE		threadpriority_t;
 #define DECLARE_THREAD_STACK(name, sz)			size_t *name = (size_t *)sz
 #define DECLARE_THREAD_FUNCTION(fnName, param)	threadreturn_t fnName(void *param)
 #define THREAD_RETURN(retval)
+
 portTickType MS2ST(portTickType ms);
 
 typedef struct {

src/gos/gos_osx.h

@@ -27,7 +27,7 @@ typedef pthread_mutex_t		gfxMutex;
 
 #define DECLARE_THREAD_FUNCTION(fnName, param)	threadreturn_t fnName(void *param)
 #define DECLARE_THREAD_STACK(name, sz)			uint8_t name[0];
-#define THREAD_RETURN(retval)					return reval
+#define THREAD_RETURN(retval)					return retval
 
 #define gfxExit()						exit(0)
 #define gfxAlloc(sz)					malloc(sz)

src/gtimer/gtimer.c

@@ -35,8 +35,7 @@ static DECLARE_THREAD_FUNCTION(GTimerThreadHandler, arg) {
 	systemticks_t	lastTime;
 	GTimerFunction	fn;
 	void			*param;
-	
-	(void)arg;
+	(void)			arg;
 
 	nxtTimeout = TIME_INFINITE;
 	lastTime = 0;
@@ -109,7 +108,7 @@ static DECLARE_THREAD_FUNCTION(GTimerThreadHandler, arg) {
 		lastTime = tm;
 		gfxMutexExit(&mutex);
 	}
-	return 0;
+	THREAD_RETURN(0);
 }
 
 void _gtimerInit(void)