NB: More precisely, the notion of throwing a homosexual off a building is derived from a broader concept of Hadith literature in that the stipulation comes either from a record of a stipulation by Abu Bakr (the Prophet's first successor) to throw homosexuals off a cliff or an opinion attributed to Ibn Abbas, one of the companions of the Prophet. This is so rather than a hadith in the stricter sense of detailing something the Prophet said or did. The notion of this punishment remained relatively obscure until the Islamic State publicised it, although in recent times invocations along those lines- that is, throwing a homosexual off a very high point- could sometimes be found in mosques (e.g. see this Channel 4 Dispatches Undercover Mosque program from years ago concerning extremism in British mosques) and on TV (e.g. Qatar TV in 2005).
In Islamic State-held areas, being gay often means a death sentence
Los Angeles Times
June 13, 2016