Why is "have to" not listed as a phrasal verb in the dictionary? "have" means to be in possession of something while "have to" means "obliged to". So "have to" seem to be non-compositional in terms of meaning with respect to the meanings of "have" and "to". Can "obligation" be expressed using the word "have" without it being followed by "to"?
Various grammatical sects profess various dogmata about phrasal verbs, but have to doesn't really fit any of them. That to isn't an ordinary preposition or adverb married to HAVE—it's a some-other-sort-of-particle married to the infinitive which follows.
One simple test:
ok I can’t put up with him. → It’s him I can’t put up with. → He’s who I can’t put up with.
ok She’s into metal. → It’s metal’s she’s into. → Metal’s what she’s into.
∗ We have to hurry. → It’s hurry we have to. → Hurry’s what we have to.
The same thing is true of the other periphrastic modals: BE able to, BE about to, BE going to, and so forth. They don’t behave like the other things that are called phrasal verbs so you need to call them something else.