Saxon

There are no conscious changes in the code for tail-call recursion but it's sensitive to other optimizations that may have changed, and may change the expression tree in a way that means we no longer recognize the tail call. We'll need to see a specific test case. (If you can't build a simple test case, a complex one will do, so long as we can run it...)

As simple as this tail call template with any input:

Works perfectly with Saxon-HE-9.7.0-18, and craches with "Too many nested template or function calls. The stylesheet may be looping." in Saxon-HE-9.8.0-3.

Thanks, please track this here:

https://saxonica.plan.io/issues/3352

Is it possible in your development cycle to implement maven snapshot version? This way you would get more prompt feed back. As present we run our code base on each new version, and then rollback to the old one with long wait for a version tick for.

I understand the benefits of this, but

(a) if we ran our full set of tests on each such snapshot, it could add a significant amount of testing effort

(b) if we didn't run our full set of tests on each such snapshot, it could add a significant number of bugs and therefore support effort.

(Subsequent events illustrated this point rather well: after committing another patch for an unrelated bug I ran the XSLT 3.0 test suite in export/import mode where each compiled stylesheet is written to an SEF file and then imported before being executed; and this test showed that the patch for this problem was incomplete. Running the full test suite in this way is something we do before a maintenance release, but it is not something we do on every commit.)