[CMake] Regression in INCLUDE_DIRECTORIES command between cmake 2.8.7 and 2.8.8?

[Marcel Loose]

Hi all,

I noticed that, starting from cmake 2.8.8, INCLUDE_DIRECTORIES no longer 
remove duplicates. I this a regression?

$ cat ../CMakeLists.txt
cmake_minimum_required(VERSION 2.6)
project(TestIncludeDirectories)

get_directory_property(_inc_dirs INCLUDE_DIRECTORIES)
message(STATUS "INCLUDE_DIRECTORIES=${_inc_dirs}")

include_directories(/usr/include)
get_directory_property(_inc_dirs INCLUDE_DIRECTORIES)
message(STATUS "INCLUDE_DIRECTORIES=${_inc_dirs}")

include_directories(/usr/include)
get_directory_property(_inc_dirs INCLUDE_DIRECTORIES)
message(STATUS "INCLUDE_DIRECTORIES=${_inc_dirs}")

$ ~/x86_64/usr/local/cmake-2.8.7/bin/cmake ..
-- INCLUDE_DIRECTORIES=
-- INCLUDE_DIRECTORIES=/usr/include
-- INCLUDE_DIRECTORIES=/usr/include
-- Configuring done
-- Generating done
-- Build files have been written to: 
/home/marcel/temp/cmake/include_directories/build

$ ~/x86_64/usr/local/cmake-2.8.8/bin/cmake ..
-- INCLUDE_DIRECTORIES=
-- INCLUDE_DIRECTORIES=/usr/include
-- INCLUDE_DIRECTORIES=/usr/include;/usr/include
-- Configuring done
-- Generating done
-- Build files have been written to: 
/home/marcel/temp/cmake/include_directories/build

Best regards,
Marcel Loose.