[CMake] Internal vs system version of a library

[Antonio Valentino]

Il giorno Thu, 6 Aug 2009 08:49:27 -0700
Tyler Roscoe <tyler at cryptio.net> ha scritto:

> On Thu, Aug 06, 2009 at 12:43:05PM +0200, Antonio Valentino wrote:
> > The unset command seems to be undocumented in cmake 2.6.2 (the one
> > packaged in ubuntu jaunty).
> > Is it new?
> 
> Newer than 2.6.2, yes. Not sure if it's different for cache variables
> but you can use set(myVar) in 2.6.2 to get the same effect for regular
> variables.
> 
> tyler

Hi Tyler,
I just made a couple of quick test and it seems to me that the
'set(myVar)' syntax is equivalent to 'set(myVar "")'.

This solution doesn't work in my case since variables are actually
reset but they are not correctly updated in the following code:
FFTW_INCLUDE_PATH, FFTWF_LIB and FFTWF_THREADS_LIB remain empty after
USE_INTERNAL_FFTW switch. 

thanks.

-- 
Antonio Valentino