jax

b72be575 - [jaxlib] Change Traceback to be a raw CPython class rather than a nanobind class.

[jaxlib] Change Traceback to be a raw CPython class rather than a nanobind class. I was hoping this change would have a positive impact on performance but it is close to neutral in my benchmarks. Still, I think this version is slightly better because it: * allocates the frames inline into the traceback object, saving at least one allocation per traceback collection * fixes a data race on the enabled flag, admittedly one that is probably troubling no-one in practice. PiperOrigin-RevId: 770862697