My CTRL-Y mapping is broken by clang_complete

[bmerry]

It doesn't happen all the time - it seems to depend on how one interacts with the completion window. Steps to reproduce on Ubuntu 13.10 with gvim 7.4:

Put the following in .vimrc (and obviously do :BundleInstall if needed to install clang_complete):

set nocompatible
filetype off
set rtp+=~/.vim/bundle/vundle/
call vundle#rc()
Bundle 'gmarik/vundle'
Bundle 'Rip-Rip/clang_complete'
filetype plugin indent on
syntax enable
inoremap <C-Y> <C-O>dd
let g:clang_library_path = '/usr/lib/llvm-3.4/lib'
let g:clang_complete_auto = 0

Open a .cpp and insert the following text:

#include <iostream>
int main() {
        std::cout.fl

Press <C-X><C-U> to trigger completion. Do not do anything to select a match; simply keep typing some letters, then press Enter. Now press <C-Y>: it will start copying characters from the previous line (the default i_CTRL-Y mapping) instead of deleting the current line (as specified by the .vimrc). Running inoremap <C-Y> reports the following mappings:

i  <C-Y>       *@<SNR>19_HandlePossibleSelectionCtrlY()
i  <C-Y>       * <C-O>dd

On the other hand, if after pressing <C-X><C-U> one presses <C-U> again to select the first match, then enter to dismiss the popup, the expected behaviour is restored.