Workaround hcc bug regarding extern "C" definitions (#30313)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/30313
See comments in code about the bug.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Test Plan: Imported from OSS
Differential Revision: D18762360
Pulled By: ezyang
fbshipit-source-id: 406a01f2f0c3722b381428c89afd67b3c3c19142