pytorch

553ccccc - [c10d] switch ProcessGroup to be managed by intrusive_ptr (#47343)

[c10d] switch ProcessGroup to be managed by intrusive_ptr (#47343) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/47343 Test Plan: Imported from OSS Reviewed By: gmagogsfm Differential Revision: D24723418 Pulled By: wanchaol fbshipit-source-id: 0463819b96c53b12bdbb3905431110d7b21beb77