Please read the general build guide for information on dependencies required for all platforms. Only Linux specific instructions are found in this file.
Should you choose not to install Qt5 via a package manager that handles dependencies for you, you may be missing some Qt5 dependencies. On Ubuntu, for example, the following additional packages are required:
libasound2 libxmu-dev libxi-dev freeglut3-dev libasound2-dev libjack0 libjack-dev libxrandr-dev libudev-dev libssl-dev