-don't know which MallocPtr has just died; if we overwrite the @List@ part,
-we can't traverse the list of all MallocPtrs.)
+don't know which ForeignObj has just died; if we overwrite the @List@ part,
+we can't traverse the list of all ForeignObjs.)
+
+The @FreeRoutine@ is a reference to the finalisation routine to call
+when the @ForeignObj@ becomes garbage -- SOF 4/96