clang-tidy install

You can use your package manager to find out which package clang-tidy provides. For example on Fedora/CentOS:

dnf whatprovides '*/clang*tidy*'

On Debian/Ubuntu you can use an analogous apt-file search command.

However, on Fedora 23 clang-tidy just isn't packaged. No match is found.

There is even an open bug report: Missing clang-query and clang-tidy

For Ubuntu/Debian, the LLVM project maintains an llvm apt repostiory. This should be the easiest way to get the latest clang-tidy. After configuring that repository and doing an apt-file update and apt-file search should return the package that provides clang-tidy.

An alternative to building from source is to use the upstream llvm pre-built binaries - they are available for Fedora, CentOS etc. For example the one for Fedora 23 does contain clang-tidy: