Combining ansible tasks to one task with one definition of "changed" - deployment

Question

As part of deployment there is a bit of compilation I want to do on the host. This consists of moving the source files, compiling the program, and removing the source files. I would want it to work in such a way that this results in just ok rather than changed if the program did not change.
This would accurately describe the situation, because if the program did not change, then by running the playbook a (assumedly) non-existent directory would be created, a command run resulting in some file that's then moved to where a identical copy used to be, and then the source files are removed and the created directory is once again non-existent.
Concretely, the tasks would be something like:
- copy:
src: src/
dest: /tmp/my_program_src/
- shell: my_compiler -o /usr/local/bin/my_program /tmp/my_program_src/main.file
become: true
- file:
path: /tmp/my_program_src/
state: absent
Of course what actually happens is that all three report "changed"; because for shell I would have to define changed_when myself, and copy as well as file change something, though they cancel each other out.
Can I group this together into one task which reports ok if /usr/local/bin/my_program did not change? If yes, then how? If no, then what would be the 'right' way to do something like this?

Answer 1

IMHO, I recommend doing the Ansible way like this. Other option is generating a script and calling it by command:. Then checking the sha1 with Ansible, but I don't like that option.
---
- name: Example
hosts: localhost
gather_facts: False
connection: local
tasks:
- name: Get cksum of my program
stat:
path : "/usr/local/bin/my_program"
register: myprogram1
- name: Current SHA1
set_fact:
mp1sha1: "{{ myprogram1.stat.checksum }}"
- name: Copy File
copy:
src: src/
dest: /tmp/my_program_src/
changed_when: False
- name: Compile
shell: my_compiler -o /usr/local/bin/my_program /tmp/my_program_src/main.file
become: true
changed_when: False
- name: Remove src
file:
path: /tmp/my_program_src/
state: absent
changed_when: False
- name: Get cksum of my program
stat:
path : "/usr/local/bin/my_program"
register: myprogram2
- name: Current SHA1
set_fact:
mp2sha1: "{{ myprogram2.stat.checksum }}"
- name: Compilation Changed
debug:
msg: "Check Compilation"
changed_when: mp2sha1 == mp1sha1