[Cmake] Variable Behavior

[Brad King]

Richard Wackerbarth wrote:

> In playing around with the Dart rules in order to get it to behave in a 
> way that I think that I want, I noticed something that wasn't consistent 
> from one run to the next.
> 
> The first run starts with an empty directory
> 
> The hostname is output by the lines
> 
>   # set the site name
>   SITE_NAME(SITE)
>   # set the build name
> 
> in the Dart.cmake module.
> 
> However, once the cache is present, the output does not occur.
> I added some MESSAGES to check. The SITE_NAME command is executed in 
> both cases.
> 
> My question is Should this happen? I seems to me that the command either 
> should always output the value, or never do so.
> 
> [Legacy] ~/TestBuildTree/dt> cmake ../../SourceTrees/dt
> -- Check for working C compiler: gcc
> -- Check for working C compiler: gcc -- works
> -- Check for working CXX compiler: c++
> -- Check for working CXX compiler: c++ -- works
> -- Check if the system is big endian
> -- Check if the system is big endian - little endian
> Legacy.Dataplex.Net
> -- Using Buildname: FreeBSD-5.2-c++
> -- Configuring done
> -- Generating done
> [Legacy] ~/TestBuildTree/dt> cmake ../../SourceTrees/dt
> -- Check for working C compiler: gcc -- works
> -- Check for working CXX compiler: c++ -- works
> -- Using Buildname: FreeBSD-5.2-c++
> -- Configuring done
> -- Generating done
> 
> [Legacy] ~/TestBuildTree/dt>

I agree this is not the desired behavior.  Please submit this as a bug:

   http://www.cmake.org/Bug

The output should probably look like this the first time:

-- Checking system host name
-- Checking system host name - Legacy.Dataplex.Net

and then not appear again.  This would make it consistent with the other 
try-compile rules.

-Brad