"Landing Field Length" is 1.67 X landing distance. So for flight ops, you have a 40% buffer to use for any reason. As an example, if the LFL is 10,000', then the a/c should come to a stop at 6000.
It's been said, as a general rule, that if you have LFL available, that there is no ONE factor that will cause you to exceed it. Zero flap, anti skid inop, manual or no spoilers, etc. Now, if you have zero flaps, anti skid inop on an icy runway,.....it just ain't your day.
A side note: In the US, the FAR that governs LFL is a "takeoff" requirement. FAR 121.195 states, "No person may TAKEOFF an airplane at such a weight", etc. There is no FAR that requires any specific runway length be available for landing.