Update blocks_runtime.h (#45)

Update blocks_runtime.h to be compatible with Apple / LLVM version.

blocks_runtime.m

@@ -42,9 +42,9 @@ static void *_HeapBlockByRef = (void*)1;
 /**
  * Returns the Objective-C type encoding for the block.
  */
-const char *block_getType_np(void *b)
+const char *block_getType_np(const void *b)
 {
-	struct Block_layout *block = b;
+	const struct Block_layout *block = b;
 	if ((NULL == block) || !(block->flags & BLOCK_HAS_SIGNATURE))
 	{
 		return NULL;
@@ -231,10 +231,10 @@ void _Block_object_dispose(const void *object, const int flags)
 
 
 // Copy a block to the heap if it's still on the stack or increments its retain count.
-void *_Block_copy(void *src)
+void *_Block_copy(const void *src)
 {
 	if (NULL == src) { return NULL; }
-	struct Block_layout *self = src;
+	struct Block_layout *self = (struct Block_layout*)src;
 	struct Block_layout *ret = self;
 
 	extern void _NSConcreteStackBlock;
@@ -265,10 +265,10 @@ void *_Block_copy(void *src)
 }
 
 // Release a block and frees the memory when the retain count hits zero.
-void _Block_release(void *src)
+void _Block_release(const void *src)
 {
 	if (NULL == src) { return; }
-	struct Block_layout *self = src;
+	struct Block_layout *self = (struct Block_layout*)src;
 
 	extern void _NSConcreteStackBlock;
 	extern void _NSConcreteMallocBlock;

objc/blocks_runtime.h

@@ -13,9 +13,9 @@
 #define BLOCKS_EXPORT extern 
 #endif
 
-BLOCKS_EXPORT void *_Block_copy(void *);
-BLOCKS_EXPORT void _Block_release(void *);
-BLOCKS_EXPORT const char *block_getType_np(void *b) OBJC_NONPORTABLE;
+BLOCKS_EXPORT void *_Block_copy(const void *);
+BLOCKS_EXPORT void _Block_release(const void *);
+BLOCKS_EXPORT const char *block_getType_np(const void *b) OBJC_NONPORTABLE;
 
-#define Block_copy(x) ((__typeof(x))_Block_copy((void *)(x)))
-#define Block_release(x) _Block_release((void *)(x))
+#define Block_copy(x) ((__typeof(x))_Block_copy((const void *)(x)))
+#define Block_release(x) _Block_release((const void *)(x))