Failure in tycho-baseline-plugin due to sudden byte-code changes

[ptziegler]

We use the tycho-baseline-plugin to verify the correct versions for our plugins. Since today, this check fails because some of the classes have changed since the latest release. Except: Those files haven't been touched in several weeks, so the bundles should be identical.

We're using the Tycho 5.0.0 snapshot and the problem only showed up within the past 8-10h, so I assume some of the recently updated dependencies are responsible for this. This problem doesn't show up if I downgrade to Tycho 4.0.2, so I don't suspect any changes to e.g. the JDK or Maven.

2023-09-15T04:08:02.4180340Z [INFO] --- tycho-baseline:5.0.0-SNAPSHOT:verify (compare-version-with-baseline) @ org.eclipse.wb.swt.widgets.baseline ---
2023-09-15T04:08:02.5946735Z [ERROR] ┌──────────────────────────┬──────────────────────────┬──────────────────────────┬─────────────────────────┬─────────────────────────┬─────────────────────────┐
2023-09-15T04:08:02.5947753Z [ERROR] │Delta                     │Type                      │Name                      │Project Version          │Baseline Version         │Suggested Version        │
2023-09-15T04:08:02.5948618Z [ERROR] ├──────────────────────────┼──────────────────────────┼──────────────────────────┼─────────────────────────┼─────────────────────────┼─────────────────────────┤
2023-09-15T04:08:02.5949314Z [ERROR] │MICRO                     │RESOURCES                 │org.eclipse.wb.swt.widgets│1.9.3                    │1.9.3                    │1.9.103                  │
2023-09-15T04:08:02.5949956Z [ERROR] │                          │                          │.baseline-1.9.3-SNAPSHOT.j│                         │                         │                         │
2023-09-15T04:08:02.5950533Z [ERROR] │                          │                          │ar                        │                         │                         │                         │
2023-09-15T04:08:02.5951280Z [ERROR] ├──────────────────────────┼──────────────────────────┼──────────────────────────┴─────────────────────────┴─────────────────────────┴─────────────────────────┤
2023-09-15T04:08:02.5952320Z [ERROR] │..CHANGED                 │CLASS                     │org/eclipse/wb/swt/widgets/baseline/Library.class                                                       │
2023-09-15T04:08:02.5953115Z [ERROR] └──────────────────────────┴──────────────────────────┴────────────────────────────────────────────────────────────────────────────────────────────────────────┘

[laeubi]

This happens because JDT has changed the compiler in regard to String handling and Tycho now uses latest ECJ by default:

• Bug 527899 [9] Implement JEP 280: Indify String Concatenation eclipse-jdt/eclipse.jdt.core#1139

You can use an older JDT compiler or bump the micro version, where the later is maybe the best way forward. Theoretical one might can detect this on the bytecode level and enhance the comparator but this is likely a hard task to perform compared to bump the micro version.

[ptziegler]

Thanks for the explanation. If it's just a one-time change, then increasing the minor version sounds like the most efficient answer.

[akurtakov]

This type of changes can happen on jdt.core version change which is released every 3 months.