[issue23821] test_pdb fails under -O

[Serhiy Storchaka]

New submission from Serhiy Storchaka:

Tests were added in issue16596.

----------
nosy: +asvetlov, gvanrossum, serhiy.storchaka, xdegaye

_______________________________________
Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue23821>
_______________________________________