const objects unable to allocate

[lyncmi07]

If an object is constant (Every version of the object is always exactly the same everytime its instantiated)
it will fail to allocate correctly in gc. This is due to an optimisation within the compiler which still simply copy the correct bytes into memory.
Because the _size variable within gc::object is being allocated prior to its actual initialisation, the compiler does not realise that this is not an accurate action to perform.

If at all possible, any changes to an object should be done after the object is initialised.

This needs to have an associated test