俱舍論記 22.54

22.54

「有餘於此至說樂亦名苦」者，有餘經部鳩摩羅多。而於此中以頌釋言：以此樂受，能為未來，苦果因故。能集未來，眾苦果故。有苦逼迫，希彼樂故。故說樂受，亦名為苦。

Regarding "Others in this regard... say that pleasure is also called suffering": another Sautrāntika, Kumāralāta, explains this in a verse, saying: Because this pleasant feeling can serve as the cause for future fruits of suffering; because it can accumulate the fruits of multiple future sufferings; and because when oppressed by suffering, one longs for that pleasure; therefore pleasant feeling is also spoken of as suffering.