Am 21.09.2018 um 21:23 schrieb Ke Gao:
So I guess in order to include the object-files from a third party
static library, the only way would be to first extract it's object-files
and then combine them?
That is how I understand it, yes.
On Fri, Sep 21, 2018 at 12:34 PM Deniz Bahadir <dbaha...@benocs.com
<mailto:dbaha...@benocs.com>> wrote:
Am 21.09.2018 um 18:38 schrieb Ke Gao:
> Hi David,
>
> It didn't give me error info. It can produce the final static
library,
> but the contents of third party static libraries are not included.
Some clarification regarding STATIC and OBJECT library targets and how
they interact with each other using `target_link_libraries`:
A STATIC library target A can be linked (via
`target_link_libraries`) to
another STATIC library target B.
`target_link_libraries(A STATIC PUBLIC B)`
However, the resulting library file libB does not contain the
information (aka object-files) of libA.
Instead, CMake makes sure to link both static library files libB and
libA when e.g. creating an executable exeC1 using target C1 which just
links (via `target_link_libraries`) to target B.
`target_link_libraries(C1 EXECUTABLE PUBLIC B)`
(Instead of an executable exeC1 you could have created a shared library
libC1 instead. The behavior is the same.)
If you instead want to create a combined, single STATIC library libC2,
which contains the object-files archived in both static library files
libA and libB created from targets A and B, then you somehow need to
extract the archived object-files from libA and libB. I am not sure if
CMake provides a (simple) way to do this.
For OBJECT libraries the behavior is like this:
An OBJECT library target X can be linked (via `target_link_libraries`)
to another OBJECT library target Y.
`target_link_libraries(Y OBJECT PUBLIC X)`
This, however, only transports the usage-requirements
(preprocessor-defines, include-paths etc.) from X to Y. The
object-files
of X are in no way referenced by Y.
So, if you then create a STATIC target Z1 that links (via
`target_link_libraries`) to Y,...
`target_link_libraries(Z1 STATIC PUBLIC Y)`
... Z1 will reference/contain the usage-requirements of X and Y and the
object-files of Y, but not the object-files of X. (The static library
file libZ1 resulting from Z1 will contain the object-libraries of Y but
not of X.)
What you should do instead is not to link the OBJECT targets X and Y
together but instead only link them (explicitly) to the STATIC
target Z2:
`target_link_libraries(Z2 STATIC PUBLIC Y X)`
Z2 then references the usage-requirements as-well-as object-files of
both OBJECT targets X and Y and the resulting static library file libZ2
will then contain the object-files of both library targets, X and Y.
>
> Also, sorry for the mistake I have made in my previous email.
Deniz is
> right, the keyword "PUBLIC" should be used in target_link_librarie().
>
> Thanks
You're welcome.
Deniz
>
> On Fri, Sep 21, 2018 at 10:06 AM David Jobet
<djo...@tower-research.com <mailto:djo...@tower-research.com>
> <mailto:djo...@tower-research.com
<mailto:djo...@tower-research.com>>> wrote:
>
> Hello,
>
> glad that could help you.
> For your newer problem, you don't describe them, so it's
tough to know
> what kind of problems you're facing.
> Maybe a small example of your CMakeLists.txt + a capture of
the error
> cmake gives you could help ?
>
> David
> On Fri, Sep 21, 2018 at 4:52 PM Ke Gao <ke.gao...@gmail.com
<mailto:ke.gao...@gmail.com>
> <mailto:ke.gao...@gmail.com <mailto:ke.gao...@gmail.com>>> wrote:
> >
> > Thank you all for the help.
> >
> > I finally use a way quite similar to David's first approach. I
> first generate all sub-projects into object libraries using
> add_library(lib1 OBJECT SOURCES). Then in the final library,
I use
> add_library(single_static_lib STATIC SOURCES) and
> target_link_libraries( single_static_lib lib1 lib2 ...). Note
that I
> didn't use " $<TARGET_OBJECTS:lib1>" in the final
"add_library" and
> also didn't use "PUBLIC" keyword in the final
> "target_link_libraries". It works on CMake v3.12.2 and gives me a
> single static lib which combines all the objs I want.
> >
> > But currently I still have problems of further combining third
> party static libraries into the final generated static
> single_static_lib. Can anybody provide a solution for this?
> >
> > Thank you very much.
> >
> > Ke
> >
> > On Fri, Sep 21, 2018 at 6:15 AM Deniz Bahadir
> <dbaha...@benocs.com <mailto:dbaha...@benocs.com>
<mailto:dbaha...@benocs.com <mailto:dbaha...@benocs.com>>> wrote:
> >>
> >> Am 21.09.2018 um 09:33 schrieb David Jobet:
> >> > Hello,
> >> >
> >> > I had a similar issue lately and wanted to "pack" several
> static libs
> >> > into a dynamic one. (Not even talking about an
INTERFACE lib
> since I
> >> > really wanted that .so)
> >> > I made it work with 3 different solutions, none of them
being
> "clean"
> >> > from my point of view.
> >> >
> >> > 1- OBJECT libs on sub projects : add_library(lib1 OBJECT
> SOURCES) and
> >> > for the single static lib :
add_library(single_static_lib STATIC
> >> > $<TARGET_OBJECTS:lib1> ...)
> >> > Problem I faced : since OBJECT libs do not support
> >> > target_link_libraries(), I had to remove the existing
one and move
> >> > them instead to the target_include_directories() using
generators.
> >>
> >> This is no longer true. Since CMake 3.12
`target_link_libraries`
> fully
> >> supports OBJECT libraries. You just need to pay attention
to the
> special
> >> case of linking an OBJECT library with keyword "PUBLIC".
> (Object-files
> >> are always private and inherited object-files are
therefore never
> >> further inherited. See:
> >>
>
https://cmake.org/cmake/help/v3.12/command/target_link_libraries.html#linking-object-libraries)
> >>
> >> > e.g : target_include_directories(lib1 PUBLIC
> >> > $<TARGET_PROPERTY:another_lib,INCLUDE_DIRECTORIES>)
> >> > Because I had a dependency to a protobuf generated lib,
I also
> had to
> >> > add manual add_dependencies to respect proper build order.
> >> > Not clean at all
> >> >
> >> > 2- add_library(mysharedlib STATIC CMakeLists.txt)
> >> > target_linked_libraries(mysharedlib PUBLIC lib1 ...)
> >> > Maybe the cleanest way I found.
> >> > The trick with CMakeLists.txt is that add_library needs at
> least one
> >> > source file. You can put any kind of files you want.
> CMakeLists.txt is
> >> > not compilable, so no extra compilation step, no need for
> dummy empty
> >> > source file and add_library is happy.
> >> > It did not work in my case because of problems related
to how
> our .so
> >> > are used/generated. (problems at runtime with duplicated
> symbols in
> >> > protobufs)
> >> >
> >> > 3- a variation around 1
> >> > instead of defining OBJECT libs, define a variable
holding all the
> >> > sources for lib1, another for lib2, ...
> >> > then just do add_library(mysharedlib STATIC
${SOURCES_FOR_lib1}
> >> > ${SOURCES_FOR_lib2})
> >> > It works a little bit like 1) but does not have any of its
> problems
> >> > (target_link, add_dependencies, generators, ...)
> >> > It has new problems of its own though : if your libs
live in
> different
> >> > subfolders, the variables might not be visible from your
> >> > add_library(mysharedlib...) call.
> >> > To work around that, you can use PARENT_SCOPE (not sure if
> that works
> >> > accross several levels), or includes (defines those
variables into
> >> > separate files living in each subfolders and include
them in the
> >> > parent CMakeLists).
> >> >
> >> > Hope this helps (and I'd be happy to know of other ways)
> >> >
> >> > David
> >> > On Thu, Sep 20, 2018 at 5:45 PM Ke Gao
<ke.gao...@gmail.com <mailto:ke.gao...@gmail.com>
> <mailto:ke.gao...@gmail.com <mailto:ke.gao...@gmail.com>>> wrote:
> >> >>
> >> >> Hi,
> >> >>
> >> >> I have a project which includes many sub-projects. Each
> sub-project generates a static library. In the main project,
I want
> to combine the generated objs, generated static libraries
from other
> sub-projects, and some other third party static libraries
together
> into a single static library. Is there an elegant way to do
this, or
> maybe an existing function?
> >> >>
> >> >> Thank you very much.
> >> >>
> >> >> --
> >> >>
>
..............................................................................................................................................
> >> >> Ke Gao
> >>
> >>
> >> Hope that information was of value,
> >> Deniz
> >>
> >> --
> >>
> >> Powered by www.kitware.com <http://www.kitware.com>
<http://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
> >
> >
> >
> > --
> >
>
..............................................................................................................................................
> > Ke Gao
> --
>
> Powered by www.kitware.com <http://www.kitware.com>
<http://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
>
>
>
> --
>
..............................................................................................................................................
> Ke Gao
>
>
--
Powered by www.kitware.com <http://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
--
..............................................................................................................................................
Ke Gao
--
BENOCS GmbH
Dipl.-Inform. Deniz Bahadir
Reuchlinstr. 10 D
10553 Berlin
Germany
Phone: +49 - 30 / 577 0004-22
Email: deniz.baha...@benocs.com
www.benocs.com
Advisory Board (Chairman): Oliver Fietz
Board of Management: Stephan Schröder, Dr.-Ing. Oliver Holschke,
Dr.-Ing. Ingmar Poese
Commercial Register: Amtsgericht Bonn HRB 19378
--
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
