There isn't anything weird, I went on #musl asked the question, the functionality is desired but it should be worked with the community to ensure correctness.
Yes, there is. I'm not just making this up. I've gotten takes from "musl people", including Rich Felker, that this was a deliberate choice, and that not only is musl's behavior of pretending that truncated UDP responses are valid acceptable, but that it's somehow better (maybe for performance?) --- that you can always serve "getaddrinfo" off of just the truncated UDP result. Which is, of course, false.
There is a weird thing going on; maybe you can relay this back to the #musl channel you're talking on, and they can keep discussing.
The functionality was explicitly not added by the developer.
> My choice not to do TCP in musl's stub resolver was based on an interpretation that truncated results are not just acceptable but better ux - not only do you save major round-trip delays to DNS but you also get a reasonable upper bound on # of addrs in result.