Man pages matching name cpu_capabilities in section 3alleg4:

cpu_capabilities.3alleg4.en	debian 10 / allegro4-doc
cpu_capabilities.3alleg4.en	debian 11 / allegro4-doc
cpu_capabilities.3alleg4.en	debian 12 / allegro4-doc
cpu_capabilities.3alleg4.en	debian 13 / allegro4-doc