Youcompleteme: not getting along with cpp; ycmdiag says no support, ycmcomplete ft=cpp gives errors

[2c2c]

:YcmDiag returns

Native filetype completion not supported for current file, cannot force recompilation.

:ycmcomplete returns

Error detected while processing function 58_CompleterCommand:
line 30:
Traceback (most recent call last):
File "", line 1, in
AttributeError: 'NoneType' object has no attribute 'OnUserCommand'

No idea where to go regarding this error

[Valloric]

Please provide a test case that repeatedly reproduces the problem. See here for details.

[Valloric]

No further information provided, closing.

[sztomi]

Maybe this helps someone: Came here from searching for a similar error. My problem was that I did not add the --clang-completer flag to the install script.