Sayyiduna Ibn Mas'ud (may Allah be pleased with him) used to prompt a man reciting the Qur'an whenever he faltered. Then he got up and began to urinate, so the man stopped reciting. Sayyiduna Ibn Mas'ud (may Allah be pleased with him) said to him: "Recite." He said: You have urinated. He said: "Recite." So he kept prompting him in that state while he was reciting.
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 8691