if (subClass == superClass) return KtSubstitutor.Empty(token)

        val baseFirSymbol = subClass.firSymbol
        val superFirSymbol = superClass.firSymbol
        val inheritancePath = collectInheritancePath(baseFirSymbol, superFirSymbol) ?: return null
        val substitutors = inheritancePath.map { (type, symbol) ->
            type.substitutorForSuperType(rootModuleSession, symbol)
        }