[CMake] What does `cross-platform' mean?

[Clinton Stimpson]

Miguel A. Figueroa-Villanueva wrote:
> On Mon, Nov 10, 2008 at 10:09 AM, Bill Hoffman wrote:
>   
>> Jed Brown wrote:
>>     
>>> Thanks Bill.  I'm very encouraged by the response this thread has
>>> generated and optimistic that the Find* modules will become more robust
>>> without undue effort by module writers.
>>>
>>>       
>> Well, it is not going to happen over night, but I think we are closer to a
>> plan.  I am going to update the wiki with the main three ideas of this
>> thread so it does not get lost.
>>
>> - Standard FOO_DIR for find modules, but environment and cache. Environment
>> works like CC and CXX do.
>>
>> - Add ability to parse compile lines like the ones produced from pkg-config
>> and turn them into full paths to libraries.
>>
>> - Add an easy way to create dependent cache variables, that when changed
>> unset a number of other variables.
>>     
>
> A while back I had opened a feature request on the third item:
>
> http://public.kitware.com/Bug/view.php?id=7286
>
> I think it is a fairly simple thing to implement if no speed issues
> are considered, which I don't think these would be a problem. That is,
> save the cache before the configure iteration and check if the entries
> listed in the dependencies list have changed. If so, reset the cache
> entry.
>
>   
I'd like that behavior available outside of a find_xxx command as well.

FindQt4.cmake has some manually set cache variables that need to be 
considered, some of which interact with other calls to find_xxx.

Clint