[Ctk-developers] CTK Update to latest DCMTK

Mon Aug 1 21:41:18 UTC 2011

FYI - In the mean time, i pushed the following commit that take care of
explicitly specifying fPIC.

See
https://github.com/commontk/CTK/commit/4b95a9bef509e62a2d86621539829165500baa48

Thanks
Jc

On Mon, Aug 1, 2011 at 2:41 PM, Jean-Christophe Fillion-Robin <
jchris.fillionr at kitware.com> wrote:

>
>
> On Mon, Aug 1, 2011 at 1:00 PM, OFFIS DICOM Team <dicom at offis.de> wrote:
>
>> Hi,
>>
>> Am 01.08.2011 18:25, schrieb Jean-Christophe Fillion-Robin:
>>
>>  Regarding MT and /MTd, would it make sens to have a CMake option named
>>> DCMTK_MULTITHREADED ?
>>>
>>
>> If CMake automatically uses the flags it should and hands it over to all
>> external projects, this would be not needed. However, I'm not sure whether
>> this is actually the case.
>>
>
> CMake could pass down any additional flags by configuring the project with
> CMAKE_CXX_FLAGS and CMAKE_C_FLAGS.
>
>
>
>>
>> We already have a WITH_THREADS flag in DCMTK which adds libpthread if
>> existing/necessary. Usually, with threads is turned on.
>
>
> Does it mean that turning WITH_THREAD OFF won't append the /MT or /MTd
> flags ?
>
>
>>
>>
>>  Yes, and totally my fault ;)
>>>
>>>
>>> No prob :) Seems we identify and are on the good track to get the problem
>>> fixed.
>>>
>>
>> Yes, I hope so :)
>>
>>
>>
>>> DCMTK build by CTK is/was broken. The flag fPIC was not added
>>> automatically ...
>>>
>>
>> Yes, ok; as I understood this is needed when linking against the shared
>> DCMTK libraries from outside.
>
> This happen when linking a shared 64bits library against  a static library.
> The fPIC flag is required.
>
>>
>>
>>  * Get write access to official dcmtk ? * Ask dcmtk folks to mirror DCMTK
>>> on github so that we can fork and easily contribute patches ? * Mirror
>>> DCMTK ourself on commontk/dcmtk
>>>
>>>
>>> I would not be happy about any of these. Let's get things running on all
>>> platforms now; I will do my part as good as possible and with priority.
>>> Then we can take a fixed commit and update that from time to time in CTK.
>>> We can do that regulary, as you like, or as I can give you a hint if
>>> interesting features (for CTK) come in.
>>>
>>>
>>> I guess submitting patch to Offis directly seems to be the way to go. We
>>>  could also publish our topic branch on commontk/DCMTK to that you can
>>> review them before final integration upstream.
>>>
>>
>> Fine for me. My point is just that we should not let drift apart CTK too
>> much from the latest DCMTK version. Otherwise (like now..;)) it is double
>> work to align things again :)
>
> Excellent - And thanks for helping us catching up with the current DCMTK.
>
>
>>
>>  Assigned issue https://github.com/commontk/__**CTK/issues/22<https://github.com/commontk/__CTK/issues/22>
>>> <https://github.com/commontk/**CTK/issues/22<https://github.com/commontk/CTK/issues/22>>
>>> to Michael
>>>
>>> In the mean time, I will update CMakeExternal/DCMTK.cmake so that fPIC is
>>> passed.
>>>
>>>
>>> Shouldn't we not just change DCMTK's CMakeLists.txt? We need these flags
>>> anyway sooner or later, so we should also take it over. I would just take
>>> over the solution from the link (issues/22) into DCMTK's CMakeLists.txt.
>>>
>>>
>>> Very true - i didn't know how responsive you would be. Do you know when
>>> things will be fixed?
>>>
>>
>> I could commit it any time/immediately in DCMTK. My colleague noted that
>> we
>> should take care that we only put -fPIC into effect if it is understood by
>> the compiler and needed, so I wonder whether "IF(UNIX" is a sufficient
>> guard. Any hints or recommendations?
>
>
> You could for example do:
>
> #-----------------------------------------------------------------------------
>
> # To fix compilation problem: relocation R_X86_64_32 against `a local symbol' can not be
> # used when making a shared object; recompile with -fPIC
> # See http://www.cmake.org/pipermail/cmake/2007-May/014350.html
>
> #
> IF( CMAKE_SYSTEM_PROCESSOR STREQUAL "x86_64" )
>
>   SET_TARGET_PROPERTIES(log4qt PROPERTIES COMPILE_FLAGS "-fPIC")
> ENDIF( CMAKE_SYSTEM_PROCESSOR STREQUAL "x86_64" )
>
>
>
>
>>
>> Best regards,
>> Michael
>>
>> --
>> OFFIS DICOM Team, Escherweg 2, 26121 Oldenburg, Germany
>> E-Mail: dicom at offis.de, URL: http://dicom.offis.de
>>
>
>
>
> --
> +1 919 869 8849
>
>

-- 
+1 919 869 8849
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