[CMake] Building a Version Header

[Tyler Roscoe]

On Wed, Jul 07, 2010 at 10:43:15PM -0400, John Drescher wrote:
> On Wed, Jul 7, 2010 at 9:44 PM, Clark Gaebel <cg.wowus.cg at gmail.com> wrote:
> > I would like to generate file that looks something like this:
> >
> >    // version.h
> >    #define VERSION "v0.1-345-ga77ede8"
> 
> You want to do that with configure_file

The upside of this approach is that it's simple. The downside is that it
is only run (and thus your version header is only updated) whenever
CMake runs. It's possible for the source code to change without
triggering a re-run of CMake.

Consequently, we use a custom command to call a python script at build
time. The script writes out the header with the up-to-date version info.

tyler