Migration refers to the conversion of existing data in the projects_root when you upgrade to a newer Klocwork version. Propagation refers to how data is mapped between analysis runs.

Depending on how many changes in the source code have occurred, changes to line and column numbers, function signatures, and function names are generally handled successfully between versions and builds. For example, if only the line number is changed, the issue will be propagated. If all of the above are changed, however, successful propagation will depend on how many similar issues are reported on that same function.

If the name of the file containing the reported issue changes, the issue will not be migrated or propagated. In addition, changing the name of a variable can often affect migration and propagation, due to the fact that the engine needs to differentiate issues related to different variables. In both these cases, the existing issue will be reported as "fixed", and a "new" issue will be reported.