Fail to call omni completion

[tenfyzhong]

Issue Prelude

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Issue Details

summary:

Fail to call omni completion.
A good commit: 263bd88

• What did you do?

When I type <c-x><c-o>, vim exist to normal mode.

• What did you expect to happen?

Include description of the expected behaviour.
And I found a good commit: 263bd88
here's a screenshot: https://asciinema.org/a/h1fxrkl299DvkVuRj37O3XWZv

1. Checkout to 263bd88
2. edit haha.c
3. type <c-x><c-o> to call omni completion

The function signature is appeared.
I expect the behaviour like this screenshot.

• What actually happened?

Fail to call omni completion when I type <c-x><c-o>.
Here is a screenshot: https://asciinema.org/a/HTiPjqHZeBaFEnWYm6J6OI3oD

Diagnostic data

Output of vim --version

https://gist.github.com/bd0582c9a4f6af08263b18fcf7be61fc

Output of YcmDebugInfo

https://gist.github.com/129614b6304d6dd144fd6170e4b1aeb8

Contents of YCM, ycmd and completion engine logfiles

Include link here to a gist containing the entire logfiles for ycm, ycmd
and any completer logfiles listed by :YcmToggleLogs.
https://gist.github.com/tenfyzhong/7fde72b5bb68b2b401365156c7198056

OS version, distribution, etc.

osx 10.10.5

Output of build/install commands

Include link to a gist containing the invocation and entire output of
install.py if reporting an installation issue.

[bstaletic]

Since #2657 YCM doeesn't use 'omnifunc'. Completion like you expect is available if you press <C-Space>.

[micbou]

Duplicate of #2735.