A man who frees a slave and then dies: who inherits from him?

Khalid narrates that Muhammad bin Sirin (may Allah have mercy on him) said, concerning a man who set his Christian slave free and then died: He will not inherit from him.

Isma'il bin Abi Hakim narrates that Umar bin Abd al-Aziz (may Allah have mercy on him) set a Christian slave of his free. Then the slave died, and he placed his inheritance in the public treasury.