This tip describes how to use C++ code completion in Vim (omni completion). When editing a C++ file, enter the command :set omnifunc? to see what completion function is currently used. If the result is omnifunc=ccomplete#Complete, it means you are using the C completion provided with Vim (not C++). If your :set omnifunc? is not set as desired or maybe empty this is a good workaround for C++ files: