Using GCC compiler on a Playstaion 3.

I am trying to store my Eigen::Matrix4f in a char array to store in a file (and send over network).
But this seems to fail...

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char data[192];
Matrix4f mat = Matrix4f::Identity(); //Or an actual matrix...
memcpy(&data[0],  &mat, sizeof(Matrix4f)); //Also tried mat.data()

//Load it back
char out[192];
//Method one
Matrix4f mat2;
memcpy(&mat2, ((Matrix4f *)&out[0]), sizeof(Matrix4f ));
//Try two
Matrix4f mat3;
mat3 = *(Matrix4f*)&msg.data[0];

The data I get is

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in:
1 0 0 0
0 1 0 0
0 0 1 0
0 0 0 1
Returns:
1.54143e-44 0 0 0
1 0 0 0
0 1 0 0
0 0 1 0

Why is it 16 bytes off? I could probably use a for loop to iterate over each float and store it manually, but that just seems so inefficient. Is this because of alignment issues, and if so, how can I solve this in a correct way?
Thanks for the help!

Edit: Using EIGEN_DONT_ALIGN_STATICALLY solved this problem, but it does seem like a lame way of solving this. Still not a good approach, how could I solve this in a more decent way?

You should really use .data() to get a pointer to the data, then you should also take into account that your char* buffers might not even satisfies the alignment required for float, so your second option is clearly wrong. using memcpy should be safe though:

char* out;
memcpy(out, mat.data(), sizeof(Matrix4f));

char* in;
memcpy(mat.data(), in, sizeof(Matrix4f));


You should also makes sure that on your platform sizeof(Matrix4f)==16*sizeof(float). This should be guaranteed by Eigen but we never tried on the PS3 platform.