Re: Assert triggered during RE_compile_and_cache

> On Aug 8, 2021, at 9:31 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>
> I realized that the earlier patch is actually a bad idea

Applying only your <fix-backref-corner-case-1.patch> to master, the following which did not crash begins to crash:

 select regexp_split_to_array('rjgykkkk', '(?:(.))((\1\1.))');

It also changes the results for another one:

 select regexp_split_to_array('jdpveoarcnsarcnsarcnszieqbqbqbqbiufdlywphbnrxtdoboouuzcqiqmenj', '()((.)){1}?\3?',
'itx');
-                                                                                     regexp_split_to_array
                                                                         

-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
-
{"","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","",""}
+                      regexp_split_to_array
+------------------------------------------------------------------
+ {jdpveoarcnsarcnsarcnszieqbqbqbqbiufdlywphbnrxtdoboouuzcqiqmenj}

I'm not sure what *should* be returned here, only that it is a behavioral change.

—
Mark Dilger
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