Fixed crashes related to dispatch_get_specific() on iOS 4.x, removed a deprecation warning.

Author: BradLarson

framework/Source/GPUImageOutput.m

@@ -18,8 +18,11 @@ void runOnMainQueueWithoutDeadlocking(void (^block)(void))
 void runSynchronouslyOnVideoProcessingQueue(void (^block)(void))
 {
     dispatch_queue_t videoProcessingQueue = [GPUImageContext sharedContextQueue];
-    
-	if(dispatch_get_specific([GPUImageContext contextKey]))
+#if (!defined(__IPHONE_6_0) || (__IPHONE_OS_VERSION_MAX_ALLOWED < __IPHONE_6_0))
+    if (dispatch_get_current_queue() == videoProcessingQueue)
+#else
+	if (dispatch_get_specific([GPUImageContext contextKey]))
+#endif
 	{
 		block();
 	}else
@@ -32,7 +35,11 @@ void runAsynchronouslyOnVideoProcessingQueue(void (^block)(void))
 {
     dispatch_queue_t videoProcessingQueue = [GPUImageContext sharedContextQueue];
 
-	if(dispatch_get_specific([GPUImageContext contextKey]))
+#if (!defined(__IPHONE_6_0) || (__IPHONE_OS_VERSION_MAX_ALLOWED < __IPHONE_6_0))
+    if (dispatch_get_current_queue() == videoProcessingQueue)
+#else
+    if (dispatch_get_specific([GPUImageContext contextKey]))
+#endif
 	{
 		block();
 	}else

framework/Source/iOS/GPUImageContext.m

@@ -27,7 +27,10 @@ - (id)init;
 
 	openGLESContextQueueKey = &openGLESContextQueueKey;
     _contextQueue = dispatch_queue_create("com.sunsetlakesoftware.GPUImage.openGLESContextQueue", NULL);
+#if (!defined(__IPHONE_6_0) || (__IPHONE_OS_VERSION_MAX_ALLOWED < __IPHONE_6_0))
+#else
 	dispatch_queue_set_specific(_contextQueue, openGLESContextQueueKey, (__bridge void *)self, NULL);
+#endif
     shaderProgramCache = [[NSMutableDictionary alloc] init];
 
     return self;

framework/Source/iOS/GPUImageMovieWriter.m

@@ -289,7 +289,10 @@ - (void)finishRecordingWithCompletionHandler:(void (^)(void))handler;
         }
         else {
             // Not running iOS 6
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
             [assetWriter finishWriting];
+#pragma clang diagnostic pop
             if (handler) handler();
         }
 #endif