Musnad Ahmad 937:85

Ishaq ibn Isa narrated to us, Yahya ibn Sulaym narrated to me, from Abdullah ibn Uthman, from Mujahid, from Ibrahim ibn al-Ashtar, from his father, from Umm Dharr, who said: When death approached Abu Dharr, I wept. He said: "What makes you weep?" I said: "Why should I not weep when you are dying in a desolate land, and I have no power to bury you, and I do not have a garment large enough to shroud you in?" He said: "Do not weep and rejoice, for I heard the Messenger of Allah, peace and blessings of Allah be upon him, say: 'No two Muslim parents lose two or three children and then remain patient and seek the reward from Allah, except that they will never see the Fire.'" "And I heard the Messenger of Allah, peace and blessings of Allah be upon him, say: 'A man among you will surely die in a desolate land, and a group of believers will witness him.' There is no one among those people except that he has died in a village or among a community, and I am the one who is dying in a desolate land. By Allah, I have not lied, nor have I been lied to."