[CMake] CMAKE_INCLUDE_CURRENT_DIR?

[Pascal Fleury]

On Tuesday 20 March 2007 07:07:35 Kishore, Jonnalagadda (IE10) wrote:
> > Kishore, Jonnalagadda (IE10) wrote:
> This is now a little confusing especially, when the description says "
> automatically add CMAKE_CURRENT_SOURCE_DIR and CMAKE_CURRENT_BINARY_DIR
> to the include directories _in every directory_"

Yes, and I think that the origin of the problem is that this very sentence can 
be interpreted in two ways that contradict themselves. Hence the confusion. 
Maybe if you can see these two ways, you'll understand :-)

SET(CMAKE_INCLUDE_CURRENT_DIR ON) has only one direct effect at the location 
of the CMakeLists.txt it is put in: set a flag to ON. This will then trigger 
an automatic INCLUDE_DIRECTORIES(${CMAKE_CURRENT_SOURCE_DIR} 
${CMAKE_CURRENT_BINARY_DIR}) in every CMakeLists.txt it will find when 
generating the Makefiles or Studio project files. It's as if you had added 
this command in every CMakeLists.txt in your project on the first line, but 
it saves you the typing.

Example project tree:

project/CMakeLists.txt
project/src/CMakeLists.txt
project/src/lib/CMakeLists.txt
project/test/CMakeLists.txt

So it you set the flag in 'project/CMakeLists.txt', and run cmake in 
$builddir/, then the directories that will be included are as follows:

project/CMakeLists.txt   --> 'project/' and '$builddir/'
project/src/CMakeLists.txt   -->  'project/src'  and '$builddir/src'
project/src/lib/CMakeLists.txt  -> 'project/src/lib' and '$builddir/src/lib'
project/test/CMakeLists.txt  -> 'project/text' and '$builddir/test'

So it will in effect "automatically add the current source dir and current 
binary dir to the include directories in every directory" as the doc says. 
However, the *current* directory has a different value when cmake is 
processing project/src/CMakeLists.txt than when processing 
project/test/CMakeLists.txt. That last part is not clearly stated in the 
docs, and may be confusing.

Hope this helps!

(don't blame me for the $builddir path, maybe it is 
$builddir/src/lib/cmake.dir/lib/src or some other internal dir, I did not 
check the proper dir structure in the builddir)

--paf