[CMake] padding link arguments to the linker

[Brad King]

Mike Jackson wrote:
>>> The -install_name option is _already_ being specified by cmake   
>>> somewhere so when I tried your suggestion, I get an error during  
>>> link  phase that the -install_name option is being specified twice.
>>> Is there a master config file somewhere for cmake that I can just   
>>> edit? How else would cmake know to put in this option?
>>
>> CMake uses the install_name to approximate UNIX rpaths in the build  
>> tree.  You will want to set VTK_USE_RPATH to OFF.  Otherwise there  is 
>> no install option anyway.
> 
> It _is_ off. Should I try a clean build at this point?

Oops, I forgot that -install_name is also used when RPATH is off but it 
just doesn't include any path.  You can do this in the build tree to get 
rid of it:

cmake . -DCMAKE_SHARED_LIBRARY_SONAME_C_FLAG:STRING= \
         -DCMAKE_SHARED_LIBRARY_SONAME_CXX_FLAG:STRING=

You could also edit Darwin.cmake in the CMake installation to get rid of 
these flags.  Also if you're using Xcode for the build they shouldn't be 
showing up anyway.  If they are please send me the complete link line it 
uses.

The right way to do this is to add a CMake feature to allow an explicit 
install_name to be specified and then update VTK to take advantage of 
the feature.  To get this done you'll have to add the feature requests I 
mentioned earlier.

-Brad