[MRELEASE-1143] MRELEASE should be able to recognise and update project.build.outputTimestamp in a profile

**[Thorsten Glaser](https://issues.apache.org/jira/secure/ViewProfile.jspa?name=mirabilos)** opened **[MRELEASE-1143](https://issues.apache.org/jira/browse/MRELEASE-1143?redirect=false)** and commented

Follow-up for: MRELEA[SE-1029](https://issues.apache.org/jira/browse/SE-1029)

I have pretty much the same problem as the ASF has in MPOM-255 and MPOM-265: I build a parent POM in a project, and I want that project's output to be reproducible, but if I set `project.build.outputTimestamp` in the parent POM itself's ``, all users inherit it. This is suboptimal (even if not harmful), especially as users' `mvn artifact:check-buildplan` will now succeed with merely...

```
[WARNING] property is inherited, it should be defined in pom.xml
```

... instead of erroring out when a user does _not_ define it.

In my parent POM, I have already defined a profile `build-mvnparent` which I enable when releasing the parent POM project itself, which defines a couple of properties such as the copyright years which I also don't want users to inherit by accident.

However, when I put the `project.build.outputTimestamp` property in there, not only do I get `mvn artifact:check-buildplan` warnings about the property being inherited when it's not (just pulled from a profile), but also does the maven-release-plugin not update it when releasing.

I would request that this be fixed, so then the ASF and I could use the profile method of defining this in the parent POM without all users of the parent-POM-once-installed inheriting that value (while all other modules in the same project that _installs_ the parent POM _do_ get it), and once it's fixed, the `artifact:check-buildplan` be updated to recognise this situation.

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No further details from [MRELEASE-1143](https://issues.apache.org/jira/browse/MRELEASE-1143?redirect=false)

Start by reviewing MRELEASE-1143 and the related MRELEASE-1029 follow-up, then trace how the maven-release-plugin updates project.build.outputTimestamp during a release. Verify behavior when the property is defined inside the build-mvnparent profile, and check the interaction with artifact:check-buildplan; done means the profile value is recognized and updated without being inherited by consumers.

Written by the indexing model from the issue text.