cet-is » art

Time estimate is for a preliminary analysis only. A better estimate of the time to fix the problem is not possible at this time.

I have started to investigate this issue, and have succeeded in building the Mu2e software against a private (and therefore changeable) version of art in debug mode, and duplicating the issue. Tuesday afternoon I hope to be able to investigate exactly what is happening.

This problem is now understood. In order to continue to detect files which really are incompatible, we must be very careful in proceeding with a fix, and several new tests must be constructed carefully in order to avoid the introduction of new problems.

Basically, "Drop metadata for dropped products" does not deal with the list of lists of BranchID for each process, which is the basis for assignment of ProductID for Ptr in products. In order to remedy this issue, we must carefully check that any product depending on a product with dropped metadata is also dropped in order to be sure that there can be no inconsistencies with references to missing or incorrect products in a particular event.

Tests for current inconsistency checking implemented with 9febe38.

Unfortunately, as we discussed, the aspects of your two files that make them unmerge-able really do make them unmerge-able, in that the histories of the single product in the two files are different, rendering safe use of Ptr in the current scheme impossible. I understand you are not using Ptr here, but we are not in a position to detect the lack of use and relax the rules within the current scheme for Ptr.

Implementation of this feature will have to wait for the transition and rationalization of the metadata to SQLite. Please contact us if you need help with a workaround in the meantime.

This issue has been resolved as a consequence of issue #16602. For art versions 2.07 and older, the rules about concatenating input files can be found here.