centos7:~$ rpm -q ansible --qf='%{name}-%{version}-%{release}\n'
ansible-2.0.0-0.git201512101810.75e6fb3.stable20.el7.centos

---
- name: First play
  hosts: localhost
  connection: local
  tasks:
    - block:
      - command: /bin/false
      rescue:
      - command: /bin/true

    - name: Add to new group
      add_host:
        name: localhost
        ip: "{{ ansible_default_ipv4.address }}"
        group: just_created
      changed_when: false

- name: Second play
  hosts: just_created
  gather_facts: false
  become: true
  tasks:
    - name: Set hostname
      debug:
        var: "{{ ip }}"

(pip)centos7:~$ ansible-playbook fail_reproducer.yml 
 [WARNING]: provided hosts list is empty, only localhost is available


PLAY [First play] **************************************************************

TASK [setup] *******************************************************************
ok: [localhost]

TASK [command] *****************************************************************
fatal: [localhost]: FAILED! => {"changed": true, "cmd": ["/bin/false"], "delta": "0:00:00.002312", "end": "2015-12-11 18:48:16.362123", "failed": true, "rc": 1, "start": "2015-12-11 18:48:16.359811", "stderr": "", "stdout": "", "stdout_lines": [], "warnings": []}

TASK [command] *****************************************************************
changed: [localhost]

TASK [Add to new group] ********************************************************
ok: [localhost]

PLAY RECAP *********************************************************************
localhost                  : ok=3    changed=1    unreachable=0    failed=1