How do I output Clang's source code transition of Blocks?

Clang Frontend Using Clang
1

For example, the Block Implementation Specification says

^ { printf(“hello world\n”); }

is translated to

struct __block_literal_1 {
void *isa;
int flags;
int reserved;
void (*invoke)(struct __block_literal_1 *);
struct __block_descriptor_1 *descriptor;
};
void __block_invoke_1(struct __block_literal_1 *_block) {
printf(“hello world\n”);
}
static struct __block_descriptor_1 {
unsigned long int reserved;
unsigned long int Block_size;
} __block_descriptor_1 = { 0, sizeof(struct __block_literal_1), __block_invoke_1 };

struct __block_literal_1 _block_literal = {
&_NSConcreteStackBlock,
(1<<29), ,
__block_invoke_1,
&__block_descriptor_1
};

Thanks for any help.
Richard Catlin