cmake_precompiled_header_example

A minimal working exampe of CMake's precompiled header feature (introduced in CMake 3.16).

Precompiled headers are a very useful tool to speed up build time, especially for large projects. They are in no way specific only to CMake, but as of CMake 3.16 they offer built-in support for generating them. This project is meant to be a minimal working example for anyone unfamiliar with how to make use of them in their own CMake project.

The CMake documentation explains precompiled headers as:

Precompiling header files can speed up compilation by creating a partially processed version of some header files, and then using that version during compilations rather than repeatedly parsing the original headers.

The CMake documentation about about precompiled headers can be found here.

Building

You can build the project with the following command:

mkdir build && cd build
cmake ..
make

Running

Run the example with:

.build/cmake_precompiled_header_example

This should print out the following to the terminal:

Hello world
Precompiled headers are cool!
This also works!
This header should not be changed often.