[cmake-developers] FindDevIL.cmake module looks for wrong header

[Brad King]

On 8/2/2011 4:41 PM, Miłosz Kosobucki wrote:
> FindDevIL.cmake module seems to be looking for il.h header instead of
> IL/il.h. This way, user should be writing
>
> #include<il.h>
>
> instead of
>
> #include<IL/il.h>
>
> in his code. Note that the latter version is used with all examples in
> DevIL library. Also libraries like OpenGL use the latter format.
>
> I hope I included the patch properly. It was tested on Windows (MSVC
> 2010) and Linux.

Unfortunately this is a backward-incompatible change.  If a CMake-based
project does

   find_package(DevIL)
   include_directories(${IL_INCLUDE_DIR})

and in its C code has

   #include <il.h>

then it would work prior to this patch and not afterward.  In order to
make this change in a compatible way you will need to use a different
variable name.

The module also needs to be fixed to follow conventions documented in
the module readme (note the difference between singular and plural names):

   http://cmake.org/gitweb?p=cmake.git;a=blob;f=Modules/readme.txt;hb=v2.8.5

Perhaps you can name all the variables with a "DevIL_" prefix and the
proper behavior you propose above.  Then provide compatible values in
the old names.

BTW, currently the FindDevIL module has no module maintainer:

   http://www.cmake.org/Wiki/CMake:Module_Maintainers

to review patches and maintain the module.  If you're interested in
becoming the maintainer for this module, let me know.

-Brad