[CI] Add ABI check for rolling

[christophfroehlich]

Is there any particular reason why there is no ABI check workflow for rolling?

Furthermore, within ros2_controllers repo we test against ROS_REPO: testing. Which is the correct one here?

[codecov]

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All modified and coverable lines are covered by tests ✅

Comparison is base (3309c6d) 48.02% compared to head (8768fbf) 48.02%.

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[destogl]

I would say that is almost the same if we use main or testing. We want to generally see if we are breaking stuff against the released packages. main is released, and testing is to be released.

We don't have an ABI check for rolling since it takes a long and it is not necessary there. We can break ABI in rolling without any considerations. So I would keep it out.

[destogl]

I don't think we need this changes here.

[christophfroehlich]

The only thing why it could be useful is to see if a PR can/should be backported. If it breaks ABI on rolling, probably not.

[destogl]

The only thing why it could be useful is to see if a PR can/should be backported. If it breaks ABI on rolling, probably not.

I think we should decide that base don functionality. Breaking ABI on rolling doesn't tell us much about ABI in humble and iron anymore.

[christophfroehlich]

I think we should decide that base don functionality. Breaking ABI on rolling doesn't tell us much about ABI in humble and iron anymore.

sure. it would be only a little help, if it breaks already on rolling, it breaks for sure on the others.

[destogl]

I think we should decide that base don functionality. Breaking ABI on rolling doesn't tell us much about ABI in humble and iron anymore.

sure. it would be only a little help, if it breaks already on rolling, it breaks for sure on the others.

That is my point: not necessary. We could have already broken ABI on rolling and on old branches will not be broken. A typical case would be that we have removed a member variable and now we have to introduce again. Variables are most common for ABI breaking.

@bmagyar what do you think? If you want just merge it