Version 9.7.117 is available upstream. Please consider updating! It seems that version 9.7.117 is available upstream, while the latest version in the Gentoo tree is 9.7.93. You think this warning is false? Read more about it here.
IRSIM is a tool for simulating digital circuits. It is a "switch-level"
simulator; that is, it treats transistors as ideal switches. Extracted
capacitance and lumped resistance values are used to make the switch a
little bit more realistic than the ideal, using the RC time constants
to predict the relative timing of events.