[CMake] LD_LIBRARY_PATH not used by the linker

[Robert Maynard]

When you dumb out the contents of VTK_LIBRARIES do you see
';/home2/softmassot/eb/Compiler/GCCcore/7.2.0/Python/2.7.14-bare/lib/libpython2.7.so'.

In general CMake will only stop using the absolute path of a library
when the library resides in an implicit directory provided by the
compiler. On Thu, Aug 2, 2018 at 4:13 PM Ruben Di Battista
<rubendibattista at gmail.com> wrote:
>
> Thanks for your answer,
>
> The thing is that, since the Python dependency comes from VTK, I checked in the VTK install directory all the CMake configuration files (In particulare the UseVTK.cmake) file to see if they keep the Python path somewhere.
>
> And it happens that yes, they do.
> If I run: `grep -e 'python2.7' -r <PATH_TO_VTK/lib/cmake/vtk-7.1>`, I actually get that in the file `VTKTargets.cmake`and in the `Modules/vtkPython.cmake` they actually keep the path of the python used to compile VTK.
>
> For example in VTKTargets.cmake, you find:
>
> set_target_properties(vtkWrappingPythonCore PROPERTIES
>   INTERFACE_LINK_LIBRARIES "vtkCommonCore;/home2/softmassot/eb/Compiler/GCCcore/7.2.0/Python/2.7.14-bare/lib/libpython2.7.so;vtksys"
> )
>
> So when I link my test target to ${VTK_LIBRARIES}, shouldn't it also be able to retrieve the right python library from the target properties?
>
>
> On Thu, Aug 2, 2018 at 9:56 PM Roger Leigh <rleigh at codelibre.net> wrote:
>>
>> It's the quick and easy way to do it.
>>
>> However, I'd suggest looking at getting CMake to use the proper path
>> without it.  Can you use any module-specific variables like
>> PYTHON_LIBRARY to override the search.  Or even just add to
>> CMAKE_PREFIX_PATH.  (Does VTK support imported targets?)
>>
>> Regards,
>> Roger
>>
>> On 02/08/18 20:43, Ruben Di Battista wrote:
>> > Hi Roger,
>> > so I explicitly passing the LDFLAGS is the way to go?
>> >
>> > On Thu, Aug 2, 2018 at 9:41 PM Roger Leigh <rleigh at codelibre.net
>> > <mailto:rleigh at codelibre.net>> wrote:
>> >
>> >     On 02/08/18 20:03, Ruben Di Battista wrote:
>> >
>> >      > I'm running cmake on a system where I have module-loaded software
>> >     such
>> >      > that `LD_LIBRARY_PATH` gets populated by the module (actually I'm
>> >     using
>> >      > Lmod) function.
>> >
>> >     LD_LIBRARY_PATH is used by the *runtime* linker, ld.so.  It is not used
>> >     when linking at *build* time, with ld.
>> --
>>
>> Powered by www.kitware.com
>>
>> Please keep messages on-topic and check the CMake FAQ at: http://www.cmake.org/Wiki/CMake_FAQ
>>
>> Kitware offers various services to support the CMake community. For more information on each offering, please visit:
>>
>> CMake Support: http://cmake.org/cmake/help/support.html
>> CMake Consulting: http://cmake.org/cmake/help/consulting.html
>> CMake Training Courses: http://cmake.org/cmake/help/training.html
>>
>> Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html
>>
>> Follow this link to subscribe/unsubscribe:
>> https://cmake.org/mailman/listinfo/cmake
>
>
>
> --
>           _
> -.     .´  |∞∞∞∞
>   ',  ;    |∞∞∞∞∞∞
>     ˜˜     |∞∞∞∞∞∞∞∞∞ RdB
>     ,.,    |∞∞∞∞∞∞
>   .'   '.  |∞∞∞∞
> -'       `'
> https://rdb.is
>
> --
>
> Powered by www.kitware.com
>
> Please keep messages on-topic and check the CMake FAQ at: http://www.cmake.org/Wiki/CMake_FAQ
>
> Kitware offers various services to support the CMake community. For more information on each offering, please visit:
>
> CMake Support: http://cmake.org/cmake/help/support.html
> CMake Consulting: http://cmake.org/cmake/help/consulting.html
> CMake Training Courses: http://cmake.org/cmake/help/training.html
>
> Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html
>
> Follow this link to subscribe/unsubscribe:
> https://cmake.org/mailman/listinfo/cmake