Default to erroring when failing to return from non-void function. (#34663)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/34663
Been bitten by this so many times. Never more.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Test Plan: Imported from OSS
Differential Revision: D20425480
Pulled By: ezyang
fbshipit-source-id: c4489efacc4149c9b57d1b8207cc872970c2501f
