[Scons-users] SCons always uses relative path even when absolute path is set with LIBPATH

Matthew Bernard matt.s.bernard at gmail.com
Mon May 28 08:24:05 EDT 2018 

I made a git repo which demonstrates the behavior.  Hopefully this can help
with the process.

https://github.com/msbm97/SConsLibBuild

On Sun, May 27, 2018 at 4:20 PM, Matthew Bernard <matt.s.bernard at gmail.com>
wrote:

> I will try once I get to my computer. I can be on in about 30 minutes I am
> away from the computer at the moment.
>
> On Sun, May 27, 2018 at 4:18 PM Bill Deegan <bill at baddogconsulting.com>
> wrote:
>
>> or at least gets the -W-l... flag on your command line.
>> (can you hop on the IRC channel?)
>>
>> On Sun, May 27, 2018 at 1:18 PM, Bill Deegan <bill at baddogconsulting.com>
>> wrote:
>>
>>> O.k try adding this:
>>> env['__RPATH'] = '$_RPATH'
>>>
>>> See if that resolves it.
>>>
>>>
>>> On Sun, May 27, 2018 at 1:12 PM, Matthew Bernard <
>>> matt.s.bernard at gmail.com> wrote:
>>>
>>>> GFortran (as a part of the gcc suite) is compiled  from the MOOSE
>>>> framework which is the external application that my code is being merged
>>>> with.
>>>>
>>>> They exclusively use Make but my application is mostly Fortran so we
>>>> really rely on scons to resolve the dependencies.
>>>>
>>>> On Sun, May 27, 2018 at 4:07 PM Bill Deegan <bill at baddogconsulting.com>
>>>> wrote:
>>>>
>>>>> How are you installing gfortran on your mac? macports? brew? other?
>>>>> (trying to replicated your environment)
>>>>>
>>>>> On Sun, May 27, 2018 at 12:32 PM, Matthew Bernard <
>>>>> matt.s.bernard at gmail.com> wrote:
>>>>>
>>>>>> Yep. That’s right. That would resolve my issue by letting the
>>>>>> external application link my code and its  dependent libraries from where
>>>>>> the external
>>>>>> Application is compiling.
>>>>>>
>>>>>> Thanks for spending time on this.
>>>>>> Matt
>>>>>>
>>>>>> On Sun, May 27, 2018 at 2:46 PM Bill Deegan <
>>>>>> bill at baddogconsulting.com> wrote:
>>>>>>
>>>>>>> It looks like you want the following in your command line for
>>>>>>> linking the shared library:
>>>>>>>
>>>>>>> gfortran -Wl,-rpath,$RPATH -o build/dynamic_lib/libdynamic_lib.dylib
>>>>>>> -dynamiclib [objectfiles]  -Lbuild/common -lcommon
>>>>>>>
>>>>>>> Does that sound right?
>>>>>>> (Where your RPATH is an absolute path)
>>>>>>>
>>>>>>> On Sun, May 27, 2018 at 11:35 AM, Matthew Bernard <
>>>>>>> matt.s.bernard at gmail.com> wrote:
>>>>>>>
>>>>>>>> My problem is that rather than using scons to build an application
>>>>>>>> as we did in the past, I am now building a set of shared libraries for an
>>>>>>>> external application to reference. Scons is linking all of the libraries
>>>>>>>> together properly but because the dependent libraries are registered with a
>>>>>>>> relative path based on where the sconstruct file is, the external
>>>>>>>> application fails to properly link the libraries.
>>>>>>>>
>>>>>>>>
>>>>>>>> The external application can properly reference everything through
>>>>>>>> the -L flag as you said, but the top level shared library (which we used to
>>>>>>>> just compile as an application) can’t find its dependent libraries which is
>>>>>>>> resolved if the files are registered with an absolute path.
>>>>>>>>
>>>>>>>> We would prefer not to resort to using LD_ Library_path as it is
>>>>>>>> not secure and we will be installing this code onto clusters once these
>>>>>>>> build problems are resolved so we will not have the ability to control
>>>>>>>> those flags anyway.
>>>>>>>>
>>>>>>>> I know it is an odd use case but I would really prefer to keep
>>>>>>>> using scons for this special case because we have built up a large set of
>>>>>>>> supported configurations for our code when compiling a application. If it
>>>>>>>> isn’t possible to do this through input, could you point me at the part of
>>>>>>>> scons that normalizes path strings?
>>>>>>>>
>>>>>>>> Thanks
>>>>>>>> Matt
>>>>>>>>
>>>>>>>> On Sun, May 27, 2018 at 1:57 PM Bill Deegan <
>>>>>>>> bill at baddogconsulting.com> wrote:
>>>>>>>>
>>>>>>>>> What's the proper flag to specify RPATH?
>>>>>>>>>
>>>>>>>>> On Fri, May 25, 2018 at 12:52 PM, Mats Wichmann <mats at wichmann.us>
>>>>>>>>> wrote:
>>>>>>>>>
>>>>>>>>>> On 05/25/2018 12:08 PM, Matthew Bernard wrote:
>>>>>>>>>> > That's right. in the sconscript I assign a build directory
>>>>>>>>>> variable to be:
>>>>>>>>>> > common_build_dir = '/Users/..../sConstructDir/build/common'
>>>>>>>>>> >
>>>>>>>>>> > and then in the sharedlibrary call my code is
>>>>>>>>>> >
>>>>>>>>>> >     tpr_lib = env.SharedLibrary(target = 'dynamic_lib',
>>>>>>>>>> >                                 source = srcs,
>>>>>>>>>> >                                 LIBS = 'common',
>>>>>>>>>> >                                 LIBPATH= common_build_dir,
>>>>>>>>>> >                                 RPATH = common_build_dir
>>>>>>>>>> >                                )
>>>>>>>>>> >
>>>>>>>>>> > so that during the linker stage I would expect to see
>>>>>>>>>> >
>>>>>>>>>> > gfortran -o build/dynamic_lib/libdynamic_lib.dylib -dynamiclib
>>>>>>>>>> [object
>>>>>>>>>> > files]  -L/Users/..../sConstruct/build/common -lcommon
>>>>>>>>>> >
>>>>>>>>>> > but during the linker stage in the build-cmds output it is
>>>>>>>>>> reported as
>>>>>>>>>> >
>>>>>>>>>> > gfortran -o build/dynamic_lib/libdynamic_lib.dylib -dynamiclib
>>>>>>>>>> [object
>>>>>>>>>> > files]  -Lbuild/common -lcommon
>>>>>>>>>>
>>>>>>>>>> Having trouble understanding what the problem is... why do you
>>>>>>>>>> want to
>>>>>>>>>> put an rpath into the library in the first place? that means
>>>>>>>>>> you're
>>>>>>>>>> hardcoding a place the dynamic linker will look for the library's
>>>>>>>>>> own
>>>>>>>>>> library dependencies - at runtime.  If you made that the same as
>>>>>>>>>> your
>>>>>>>>>> build location, that means the final binary will always need that
>>>>>>>>>> build
>>>>>>>>>> area to be present, or the libraries won't be found. Unlikely to
>>>>>>>>>> be
>>>>>>>>>> right for production.  This is nothing to do with scons, and
>>>>>>>>>> nothing to
>>>>>>>>>> do with whether the rpath is relative or absolute, although
>>>>>>>>>> arguably the
>>>>>>>>>> problem is more complex if it's relative.  If you use an rpath, it
>>>>>>>>>> should point to the place where the libraries are going to be
>>>>>>>>>> /installed/, not where they're built.  This has nothing to do with
>>>>>>>>>> finding the dependent libraries at link time - when you do your
>>>>>>>>>> second
>>>>>>>>>> link in the project using Make.  That link has to have -L
>>>>>>>>>> instructions
>>>>>>>>>> to point to where to find those libraries for linking purposes.
>>>>>>>>>>
>>>>>>>>>> I know the Mac has funky extra stuff, look up @executable_path.
>>>>>>>>>> Not a
>>>>>>>>>> Mac user so don't know what's going on with that.  Otherwise,
>>>>>>>>>> instead of
>>>>>>>>>> rpath you can use LD_LIBRARY_PATH (with caution) on linux,
>>>>>>>>>> DYLD_LIBRARY_PATH and DYLD_FALLBACK_LIBRARY_PATH on Mac.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> _______________________________________________
>>>>>>>>>> Scons-users mailing list
>>>>>>>>>> Scons-users at scons.org
>>>>>>>>>> https://pairlist4.pair.net/mailman/listinfo/scons-users
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>> _______________________________________________
>>>>>>>>> Scons-users mailing list
>>>>>>>>> Scons-users at scons.org
>>>>>>>>> https://pairlist4.pair.net/mailman/listinfo/scons-users
>>>>>>>>>
>>>>>>>>
>>>>>>>> _______________________________________________
>>>>>>>> Scons-users mailing list
>>>>>>>> Scons-users at scons.org
>>>>>>>> https://pairlist4.pair.net/mailman/listinfo/scons-users
>>>>>>>>
>>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> Scons-users mailing list
>>>>>>> Scons-users at scons.org
>>>>>>> https://pairlist4.pair.net/mailman/listinfo/scons-users
>>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> Scons-users mailing list
>>>>>> Scons-users at scons.org
>>>>>> https://pairlist4.pair.net/mailman/listinfo/scons-users
>>>>>>
>>>>>>
>>>>> _______________________________________________
>>>>> Scons-users mailing list
>>>>> Scons-users at scons.org
>>>>> https://pairlist4.pair.net/mailman/listinfo/scons-users
>>>>>
>>>>
>>>> _______________________________________________
>>>> Scons-users mailing list
>>>> Scons-users at scons.org
>>>> https://pairlist4.pair.net/mailman/listinfo/scons-users
>>>>
>>>>
>>>
>> _______________________________________________
>> Scons-users mailing list
>> Scons-users at scons.org
>> https://pairlist4.pair.net/mailman/listinfo/scons-users
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://pairlist4.pair.net/pipermail/scons-users/attachments/20180528/ed6748b0/attachment.html>

More information about the Scons-users mailing list