Reproduce :
git clone https://github.com/gaelL/_ansible2_bug_include
cd _ansible2_bug_include
ansible-playbook -i hosts site.yml
Files :
./hosts
./site.yml
./roles/bar/meta/main.yml
./roles/foo/tasks/include_level2.yml
./roles/foo/tasks/main.yml
./roles/foo/tasks/include_level1.yml
./roles/foo/defaults/main.yml