Ruling on facing or turning one's back to the qiblah when relieving oneself

Question:
Is it permissible to face the qiblah while urinating or defecating inside a building? And what is the evidence for that if it is permissible?

Answer:
It is recommended that one not face it, neither inside a building nor outside; because the hadiths that prohibited it are general, and the Prophet (peace and blessings be upon him) prohibited facing it and turning one's back to it during defecation and urination.
Therefore, a believer should not face it or turn his back to it, whether in a building or in the desert. However, it is easier in a building, and a group of scholars, including al-Bukhari (may Allah have mercy on him) and others, held this view. They argued with the hadith of Ibn 'Umar in the two Sahihs: that he saw the Prophet (peace and blessings be upon him) relieving himself on two bricks in the house of Hafsa, facing Syria and turning his back to the Ka'bah. They said: This indicates permissibility in a building between walls, but not in the desert.
Other scholars said: It is general for the desert and buildings, and what the Prophet (peace and blessings be upon him) did in the house of Hafsa was before the prohibition, or it was specific to him (peace and blessings be upon him). The best course for a believer is to be cautious and not face it if it is easy for him to do so, neither in the desert nor in a building; acting in accordance with the generality of the hadiths, avoiding the disagreement of scholars, and being cautious regarding the religion.