You should use the irccd version provided by your package manger if possible. If irccd is not available, you can build it from sources.
To build from sources, you need the following installed on your system:
Warning: don't even try to compile with GCC 4.x, it will not work due to missing C++14 features.
When you're ready, extract the irccd-x.y.z.tar.gz where x.y.z is the current version. Go to that directory, then type the following commands:
$ mkdir _build_ $ cd _build_ $ cmake .. $ make $ sudo make install
This is the quick way of compiling and installing. It's also possible to set some options to customize the build.