Not able to hide <# and #> with parameters for clang_snippets=1 with clang_complete

Question

I've set this on my .vimrc:

let g:clang_snippets=1
let g:clang_snippets_engine='clang_complete'
let g:clang_conceal_snippets=1
set conceallevel=2 concealcursor=inv

I don't know how conceal is expected to work, maybe the clang_complete's docs should have a tip for a specific setting to hide the snippets adorns.

How do I hide it? I'm using MacVim built with +conceal, but it's not working. This is my messy .vimrc by now.

NOTE: I'm sticking with g:clang_snippets_engine='clang_complete' because it seems to be more smart than the snipMate parameter completion, switching to NORMAL mode is a wiser choice to navigate between parameters since I can use SuperTab completion for params in INSERT mode while being able to navigate through them with the same tab at NORMAL mode. snipMate engine was acting weird to me sometimes too, sometimes it switched to a parameter after a completion, sometimes not.

Also, I'm missing a final tab to go after the last parameter, right after the function call (snipMate does that), so I can just insert ; and hit Enter.

Disclaimer: This question is related with the issue at https://github.com/Rip-Rip/clang_complete/issues/176.

EDIT:

My problem was with this line at my .vimrc:

au BufNewFile,BufRead *.cpp set syntax=cpp11

I'm using C++11 Syntax Support and @xaizek has discovered and pointed it out as the problem in the comments bellow in the accepted response, it seems the root cause is the use of the syntax clear command in it.

Answer 1

According to :help 'concealcursor':

Sets the modes in which text in the cursor line can also be concealed.
When the current mode is listed then concealing happens just like in
other lines.
  n     Normal mode
  v     Visual mode
  i     Insert mode
  c     Command line editing, for 'incsearch'

So with concealcursor=iv you asked Vim to hide concealed text in insert and visual modes, but show it in normal mode. So just do:

:set concealcursor=inv