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

[Brandon J. Van Every]

Brad King wrote:
> Brandon J. Van Every wrote:
>> I have investigated, and I'm not convinced that the -ldl is coming 
>> from my code.  My code is:
>>
>> CHECK_INCLUDE_FILE(dl.h HAVE_DL_H)
>> IF(HAVE_DL_H)
>>   ADD_DEFINITIONS(-DHAVE_DL_H)
>>   SET(EXTRA_LIBS ${EXTRA_LIBS} ldl)
>> ENDIF(HAVE_DL_H)
>>
>> There is no dl.h on any hard drive of my system.  Which is to be 
>> expected, as it's a Linux thing.  I think the -ldl more likely from 
>> building CMake 2.4.2 on Cygwin incorrectly.  I will await your 
>> canonical version and see if the problem goes away.
>
> What does HAVE_DL_H say in your cache?  

//Have include dl.h
HAVE_DL_H:INTERNAL=

> If you remove the entry manually from the file does it come back with 
> "yes"?
>

When I run ccmake again, it comes back with exactly the same thing.

To be very sure of the conclusion, I comment out the entire 
CHECK_INCLUDE_FILE sequence.
Now there is no way for my code to be inserting a -ldl.  It still shows up.

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


I'm inclined to believe that the CMake 2.4.2 build on Cygwin has an 
error in it somewhere.

Cheers,
Brandon Van Every