PCRE2 breaks rpl so that it fails for many uses. It should also cause a
FTBFS, because the test suite dose not pass when rpl is built against PCRE2
10.47.

The upstream issue is here: https://github.com/PCRE2Project/pcre2/issues/846

The good news is that this should be fixed in 10.48, as there’s a patch
proposed which I have already tested.

It have not found a workaround for rpl for 10.47, so it would be good if
that version of PCRE2 didn’t make it into testing.