俱舍論記 22.61

22.61

「有餘部師至受唯是苦」者，敘異計。有餘經部、大眾部等作如是執：定無實樂，一切三受皆唯是苦。此中應言：定無樂、捨，三受唯苦。為前但問樂受，故敘異宗但言無樂，不言無捨。

Regarding "Masters of other schools... feeling is solely suffering": this relates a different doctrine. Other Sautrāntikas, Mahāsāṃghikas, and so on hold this view: Definitely there is no real pleasure; all three feelings are solely suffering. Here one should say: Definitely there is neither pleasure nor neutrality; the three feelings are solely suffering. Because previously only pleasant feeling was asked about, in recounting the other school's view he merely states there is no pleasure, without stating there is no neutrality.