Automatic Git Version in CMake and CPack

This is an example of automatically generating the version number for a CMake1 based project from the value returned by git describe. This version number is used for the version returned by a c program and the version used by CPack when packaging the source and binary distributions.

The version generation should work for in-source and out-of-source builds from the git repository and from source packaged by CPack.

To support builds from source packages a VERSION file is included when source distributions are generated by CPack.

Note this requires that git describe can describe something. Thus, there must be at least one annotated tag in the git repository (see the -a and -s options to git tag).

Example usage

In-source build from the git repository:

git clone https://github.com/lcw/cmake_git_version.git
cd cmake_git_version
cmake .
make

Out-of-source build from the git repository:

git clone https://github.com/lcw/cmake_git_version.git
mkdir build
cd build
cmake ../cmake_git_version
make

Generate a source package from an out-of-source build run:

make dist

Generate a binary package:

make package

Build from the source package:

tar xzvf VERSIONHEADER-0.1.0-2-gaae0565-Source.tar.gz
cd VERSIONHEADER-0.1.0-2-gaae0565-Source
cmake .
make

Acknowledgements

This is an example I have cobbled together from various code snippets in emails to the CMake mailing list including 2 and 3 among others.