Sin can not be forgiven SHIRK

What is meant by the sin of shirk can not be forgiven is if someone does shirk and die with that sin without repentance before. The difference with sin except Shirk is the sin that when carried to death without repentance before, there is still the possibility of forgiveness of Allah. For example, to be redeemed by the deeds of its virtues. As Allah Almighty:
"... Verily the good deeds that wipe out bad deeds. That's a warning for people who remember. "(Surah Hud: 114)
Or the person in the afterlife get intercession of the Prophet Muhammad, so that his sins are forgiven and that question does not need to be punished in hell. All that may happen so it is said that sin than shirk will be forgiven in the hereafter.

But when sin brought death is sin of shirk, the sin that can not be redeemed or forgiven in the hereafter. So the question must get punishment obviously painful. That mean that the sin of shirk can not be forgiven, as mentioned in the following verses:
"Verily Allah will not forgive the sin of shirk, and He forgives all sins apart from it, to whom He wills. Whoever is to Allah, then indeed he has a great sin. "(Surat an-Nisa 48)
"Verily Allah does not forgive associating with him, and he forgives sins except shirk for whom He wills. Those who ascribe to Allah, then indeed he has strayed far, far away. "(Surat an-Nisa: 114)
Because it was during the life still in the biological body, haste to get forgiveness from Allah SWT, especially related to the sin of shirk.
"And ye haste to the forgiveness of your Lord, and for Paradise as wide as the heavens and the earth, prepared for those who fear Allah." (Surah Al 'Imran: 133)