On Tue, 14 Jun 2016, I wrote:
> While looking into this weird effect I have realized that the code for
> pcre2_get_error_message() is buggy in another way, and also not as
> robust as it should be. I am going to implement a testing facility and
> then fix the issue. Watch this space.
The most recent commit (526) now makes pcre2_get_error_message() return
a negative error code if the errorcode argument is unrecognized. This
can be tested by a small addition to pcre2test.