For C++, I use https://github.com/abingham/emacs-ycmd https://github.com/abingham/emacs-ycmd which gives completion (uses company-mode) and code navigation. It

For C++, I use https://github.com/abingham/emacs-ycmd https://github.com/abingham/emacs-ycmd which gives completion (uses company-mode) and code navigation. It can also do C, C#, js, go, python etc. Requires a little setup (you have to install the ycmd daemon and, depending on language, a per-project conf file), but worth it. An alternative to ycmd is https://github.com/Andersbakken/rtags https://github.com/Andersbakken/rtags which I think can list all usages of a symbol – ycmd only lets you go from usage to definition. I like how ycmd.el runs the ycmd daemon for me though.