[CMake] CMake 2.4.2 Cygwin shouldn't have -ldl

[Brad King]

Brandon J. Van Every wrote:
> I built a CMake 2.4.2 for Cygwin from sources.  I used the "Unix 
> linefeed" download, cmake-2.4.2.tar.gz.  I used an earlier Cygwin CMake 
> package to build it.  Now I am using this Cygwin CCMake 2.4.2 to 
> generate my Chicken build.  When it comes time to link a .dll, it fails 
> with:
> 
> Linking C shared library libchicken.dll
> /usr/lib/gcc/i686-pc-cygwin/3.4.4/../../../../i686-pc-cygwin/bin/ld: 
> cannot find
> -ldl
> collect2: ld returned 1 exit status
> make[2]: *** [libchicken.dll] Error 1
> make[1]: *** [CMakeFiles/libchicken.dir/all] Error 2
> make: *** [all] Error 2

If libchicken is trying to link to -ldl this is probably because you are 
telling to do so somewhere in your CMakeLists.txt code.

-Brad