Let $M$ be a smooth manifold, and let $\nabla$ denote a connection on $M$.
Question: If $M$ is compact, is every maximal geodesic of $\nabla$ defined for all $t\in \mathbb{R}$?
I know that, if $M$ is a Riemannian manifold and $\nabla$ its Levi-Civita connection, then the answer is yes. Maybe the proof sketched in this answer could work in this case too?