[CMake] Setting RPATH lookup on macOS

[Michael Jackson]

On macOS you really should _not_ have to copy the libraries into the build tree. I have never had to do that in 10 years of our product (Windows is a different story). The trick is setting the correct options to add in the paths to the libraries into the RPATH of the executable/library. (at least on macOS & Linux systems).

 

--

Mike Jackson

 

 

From: Juan Sanchez <juan.e.sanchez at gmail.com>
Date: Thursday, September 12, 2019 at 11:35 AM
To: Michael Jackson <mike.jackson at bluequartz.net>
Cc: CMake <cmake at cmake.org>
Subject: Re: [CMake] Setting RPATH lookup on macOS

 

The macOS install_name_tool can be used to change the RPATH of your binaries.  It can also be used to set the path for each of the libraries to be loaded.  For a python module I compile, I copy each of its dylib into the appropriate directory relative to my shared library.  I then use the install_name_tool to change from an absolute path to a path relative to @loader_path.

 

install_name_tool -change $j "@loader_path/../gcc/`basename $j`" $i
where $j is the full path output from "otool -L" and "@loader_path/../gcc" would point to a directory "gcc" relative to the directory containing my python module.

For a binary executable, I would explore placing required dylib files into a directory relative to @executable_path.

Regards,

 

Juan


 

On Wed, Sep 11, 2019 at 4:33 PM Michael Jackson <mike.jackson at bluequartz.net> wrote:

Already looked on google and at the CMake documentation but everything listed does not seem to work so here is the setup.

I am using MKL and I have a home grown FindMKL since there isn’t an official one. Inside that is the typical find_library() calls which will find the libraries just fine. One of those libraries is a dynamic library (.dylib). Using otool -L on that library the install_name is encoded as @rpath. 

Now I have my add_executable(foo…) and target_link_libraries (Foo ${MKL_LIBRARIES} ).

Everything compiles and links fine. The issue is at runtime. The app will not launch because libmkl_rt.dylib is not loaded because the path to that library is not encoded into the executable.

639:[mjackson at ferb:ifort-release]$ otool -l Bin/EMsoftWorkbench.app/Contents/MacOS/EMsoftWorkbench | grep "path"
         name @rpath/libEbsdLib.dylib (offset 24)
         name @rpath/libmkl_rt.dylib (offset 24)
         name @rpath/QtOpenGL.framework/Versions/5/QtOpenGL (offset 24)
         name @rpath/QtNetwork.framework/Versions/5/QtNetwork (offset 24)
         name @rpath/QtConcurrent.framework/Versions/5/QtConcurrent (offset 24)
         name @rpath/QtWidgets.framework/Versions/5/QtWidgets (offset 24)
         name @rpath/QtGui.framework/Versions/5/QtGui (offset 24)
         name @rpath/QtCore.framework/Versions/5/QtCore (offset 24)
         path /Users/Shared/EMsoft_SDK-ifort/EbsdLib-0.1-Release/lib (offset 12)
         path /Users/Shared/EMsoft_SDK-ifort/Qt5.12.3/5.12.3/clang_64/lib (offset 12)


Oddly the Qt libraries and one of my own libraries do get their rpaths encoded. I feel like I need to append to the RPATH that gets encoded into the executable but I am not really figuring out how to do that.

Help....

--
Michael Jackson | Owner, President
      BlueQuartz Software
[e] mike.jackson at bluequartz.net
[w] www.bluequartz.net <http://www.bluequartz.net>


-- 

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

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://cmake.org/pipermail/cmake/attachments/20190912/9ef8b293/attachment-0001.html>