My answer here to you is based on information that I know from a person who works in a VISA department in an embassy.

You should carry with you:

The VISA: for entry
The old passport: upon entry, they will need to verify that the VISA had been initially issued to an actual passport number.
The new passport: you definately need it as it has become your legal way of traveling after the first one was canceled due to damage I'm assuming.

This is typically generally the case, but I wouldn't know if they have different rules in the Qatari Airport. So double check on what I told you, it's no laughing matter to arrive at the airport and be denied entry.

Good Luck.

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" God allows life to be rocky. His challenge is not to let the rocks grind you into dust, but to polish you to become a brilliant gem. "