You will find the answer you seek not from an LLM, but from the talk Forward Progress Guarantees in C++ by Olivier Giroux at CppNow 2023. It's a long talk, with lots of details about forward progress, but I've set the timestamp[1] to the infinite loop bit.

[1]: https://youtu.be/g9Rgu6YEuqY?si=_l9JwKhjvIdFEDEX&t=3819