Thread: Bit Packing Issue

I've tried searching for this but I can't find a specific thread about what I'm seeing.

Code:

//FLAC METADATA_BLOCK_STREAMINFO
struct streaminfo {
	uint16_t min_block_size:16;    //16 bits, 0 bits left
	uint16_t max_block_size:16;    //32 bits, 0 bits left
	uint32_t min_frame_size:24;    //64 bits, 8 bits left
	uint32_t max_frame_size:24;    //96 bits, 16 bits left
	uint32_t sample_rate:20;       //128 bits, 28 bits left
	uint32_t num_channels:3;       //128 bits, 25 bits left
	uint32_t bits_per_sample:5;    //128 bits, 20 bits left
	uint64_t total_samples:36;     //192 bits, 48 bits left
	uint32_t md5_sig1:32;          //Why doesn't this fit in the 192?
	//uint16_t md5_sig2:16;
} __attribute__ ((packed));

Have I done my math right? Shouldn't that fit in the remainder of the allocated bits? I'm doing a sizeof() on my system and I'm getting 28 bytes (224 bits).

FYI I'm using gcc 4.8.0 (mingw32).

Thanks!

Edit: Should alignment be a concern? 192 bits (24 bytes) is divisible by 4 bytes, which I think is the default alignment.