[CMake] File modification detection based on content (not timestamp)

[Robin Vobruba]

> On Wed, Jan 7, 2009 at 5:19 PM, John Drescher <drescherjm at gmail.com> wrote:
>  >> ### QUESTIONS ###
>  >> 1. Is file modification detection based on file content instead of
>  >> timestamp supported already?
>  >> 2. Is support for it planned?
>  >> If not, i would like to make a feature request!
>  >> 3. How hard would it be to implement that?
>  >>
>  > I could be totally wrong but doesn't CMake have nothing to do with
>  > this? I mean CMake generates Visual Studio Projects, unix makefiles
>  > ... and its up to whatever build system you use to handle its
>  > dependencies how correctly.
>  >
>
> Bad choice of words. Should have been its up to the build system to
>  detect what files have changed and use the rules of the project file
>  to determine what to build.
>

If you go here:
http://en.wikipedia.org/wiki/CMake#Major_features
The feature list contains the following item:
* Detection of file content changes using traditional timestamps
This makes me think that CMake nearly guarantees to use only timestamps.

Also, i usually generate GCC makefiles with CMake, and they use only
timestamps. Make itsself does not have the functionality integrated,
as much as i know, so it has to be added by cmake. Automake eg, also
adds this functionality to makefiles. I do not know about VS projects,
maybe that always uses tiemstamps only, or you CMake specifies this
via a projectfile internal flag or something.
short: i think it is CMakes "fault".