Get rid of -u (expansion of undefined variable) setting (#26907)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/26907
Somehow CircleCI broke this on update to their OS X workers;
the error looks like
/bin/bash: line 1: PROMPT_COMMAND: unbound variable
I'm not sure if I've killed all the occurrences that are necessary,
let's see!
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Test Plan: Imported from OSS
Differential Revision: D17607486
Pulled By: ezyang
fbshipit-source-id: 5e9a7ff69d4b18e759965bf97c67d38404841187
