[cmake-developers] why can target_include_directories() not be applied to custom targets?

[Drew Parsons]

On Mon, 2018-07-09 at 16:02 +0300, Attila Krasznahorkay wrote:
> Hi,
> 
> Just to say that setting INCLUDE_DIRECTORIES on a custom target is
> indeed a bit of an obscure thing, but we do use it. You can find the
> full reasoning in:
> 
> https://gitlab.kitware.com/cmake/cmake/issues/16830
> 
> Because of that, I understood that CMake will provide this
> functionality in the future as well, so we can rely on this build
> setup.
> 
> Cheers,
>           Attila
> 
> > On 8 Jul 2018, at 12:16, Petr Kmoch <petr.kmoch at gmail.com> wrote:
> > 
> > Hi Drew,
> > 
> > a custom target can do literally anything, it's just a buildsystem
> > wrapper for running arbitrary executables; or often not even that,
> > and is just a collection of custom commands. There is nothing CMake
> > automatically does with the properties
> > [INTERFACE_]INCLUDE_DIRECTORIES set on a custom command.


Thanks for the explanation Petr, and Attila.

Looks like 

  set_property(TARGET mylib PROPERTY INCLUDE_DIRECTORIES ${CMAKE_CURRENT_SOURCE_DIR})

does what I have in mind, it can stand in place of
target_include_directories() for custom targets.

Drew