DeepSpeed

d9f3d40a - Raise clear error on in-place GatheredParameters edits without modifier_rank (#7817)

Raise clear error on in-place GatheredParameters edits without modifier_rank (#7817) Fix #7811 Issue: ZeRO-3 crashes when `zero.GatheredParameters` is used with `modifier_rank=None` and a parameter is modified in-place. The failure surfaced as an internal invariant assert in free_param, which is not actionable for users. Solution: `GatheredParameters` now detects in-place mutation with `modifier_rank=None` and raises a clear, user-facing error early. The mutation check is synchronized across ranks to avoid divergence and hangs. This PR also raises a clearer error from free_param when parameters are still active in submodules.” --------- Signed-off-by: Masahiro Tanaka <mtanaka@anyscale.com>