Can't believe I never noticed this. I've used GLM a bunch before.
It's funny, and it's nice, but it's not quite the ironclad level of "NO MILITARIES" as I'd like. Plus, enforceability becomes a question with classified military stuff, not even going into the actual legal discovery process. A common license would suffice for me, as I'm not going to modify the GPL as they did.
https://github.com/g-truc/glm?tab=License-1-ov-file#readme