If you have got compartment in any of the paper of 12th boards, then you are not eligible for Clat examination. Because atleast 45% marks is required to give this examination and since you got compart, the question of percentage will not rise. However, if you cleared your compartment exam,, then you will apply for the clat exam next year. Or else if your result of compartment exam will be declared before the clat exam, then also you can apply. 

All the best!