bug#19330: bug in grep -Pv ":\n" or even in rep -Pv ":\n"

[Arul, Shankari Swetaambari]

Hi,

The grep expression grep -Pv ":\n" or  even in rep -Pv ":\n" is not working as 
expected.
Did anyone report a bug on this?

Ex: The above expression does not filter the following text always -
foo:

Sometimes it works but not always.

Thanks,
Shankari