code completion does not work with C++11 after building

[litecpp]

I create a new project with -std=c++11, it works fine after building.
After I change -std=c++11 to -std=c++14 or -std=c++1z, there is a problem.
I change std from settings -> building settings -> compliers -> g++ -> c++ complier g++ -std=c++11

step 1: creating a new project with -std=c++11
step 2: build, ok
step 3: changing -std=c++11 to -std=c++14
step 4: build, code completion does not with c++11

Now I use -std=c++11, code completion works fine after building, but not with -std=c++14 or -std=c++1z

see log