[CMake] diagnosing "could not COPY_FILE" during configure

[Bill Hoffman]

On 5/25/2010 2:17 PM, Simmons, Aaron wrote:
>> Run cmake with --debug-trycompile.
>
> Oddly, with "--debug-trycompile" the problem goes away (!) and CMakeErrors.log doesn't have any mention of try compile failing.
>

Start with a clean build tree, the problem did not go away.  It would 
have worked with just a second run.

-Bill