> I'm not that sure that this is the "expected" behavior Yes, now it looks like a bug to me, too. Being written as it was in the last message, > target_sources(lib INTERFACE lib.h) can be treated as the equivalent of > target_sources(main PRIVATE lib.h) (and therefore generating an error).
However,
> target_include_directories(lib INTERFACE "${CMAKE_CURRENT_SOURCE_DIR}")
on the command line resolves to
> -I/home/l2y/<...>/lib
and
> target_include_directories(lib INTERFACE ".")
resolves to
> -I/home/l2y/<...>/lib/.
Also, looking at `<build_dir>/main/CMakeFiles/main.dir/depend.internal`:
> main/CMakeFiles/main.dir/main.c.o
> ../lib/lib.h
> /home/l2y/<...>/main/main.c
So, all elements in `target_include_directories()` resolve to full
paths, as well as `target_sources()`, while `target_sources(INTERFACE)`
stay relative, which causes trouble.
On 11.12.2017 09:20, Eric Noulard wrote:
>
>
> 2017-12-09 1:37 GMT+01:00 Oleksii Vilchanskyi
> <oleksii.vilchans...@gmail.com <mailto:oleksii.vilchans...@gmail.com>>:
>
> Hello Eric,
>
> > Why should I do that?
> > Is this the expected behavior / way to create header only library?
>
> Yes, this is the expected behaviour. CMake interprets a relative path to
> the file according to the target's add_library() or add_executable()
> call directory. I will provide a minimal, reproducible example:
>
>
> Hi Oleksii,
>
> Thanks you for the minimal reproducible example.
> I'm bot that sure that this is the "expected" behavior
>
>
> Listfile under `lib`:
>
> > add_library(lib INTERFACE)
> > target_include_directories(lib INTERFACE
> "${CMAKE_CURRENT_SOURCE_DIR}")
> > target_sources(lib INTERFACE "lib.h")
>
>
> With the previous one would expect that any target linking to this
> interface target
> will be provided with the include directories provided in its interface.
> In your case (and in mine too) this is given with **full path**
>
>
>
> Listfile under `main`:
>
> > add_executable(main "main.c")
> > target_link_libraries(main PRIVATE lib)
>
> Now, let's look at the diagnostics:
>
> > CMake Error at main/CMakeLists.txt:1 (add_executable):
> > Cannot find source file:
> >
> > lib.h
>
> So, the problem occurs when CMake cannot find `lib.h` relatively to
> `add_executable(main "main.c")` call. Whether it's the expected
> behaviour is debatable (I personally would prefer CMake to search
> relatively to `add_library(lib INTERFACE)`), and the documentation is
> silent on this caveat either, so there's that.
>
>
> Yes precisely. This seems to work OK for imported targets but not for
> header-only in-project lib.
>
>
>
> One way to solve this is to provide a path to `lib.h` relatively to
> `main` directory, another way is to provide a full path.
>
>
> We (you and me) already provide
> target_include_directories
> with full path.
>
> I cannot provide the file themselves with relative path since they may
> be used
> from different place.
>
> I guess I will open an issue unless someone explain me the rational
> behind that behavior.
>
>
> --
> Eric
--
Regards,
Oleksii Vilchanskyi
PGP:0x8D3A0E046BDE941F2A53867CE3FD952D48C0B338
signature.asc
Description: OpenPGP digital signature
-- 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: http://public.kitware.com/mailman/listinfo/cmake
