My search-fu is failing me today, so:
When a deity grants a domain with spells that have alignment descriptors opposing the deities, does the cleric get to cast them or may it just end up with some less useful domain spell slots?
There are a couple of Empyreal Lords that offer Death, which has a lot of [evil] spells. One (Damerrich) even offers an evil spell as a spell-like with its Celestial Obedience.
It's the second option. Especially with good clerics of neutral deities, just because your deity offers a spell does not always mean you can cast it. The bit for spells for cleric specifically says, "You can't cast cleric spells that are opposed to either you and your deity's alignment."
I was assuming the second, was just thrown by how evil the Death domain list was when looking at it with a good deity. You would have to be certain you liked the spells from your other domain.