Re: Errors in our encoding conversion tables

I wrote:
> There's a discussion over at
> http://www.postgresql.org/message-id/flat/2sa(dot)Dhu5(dot)1hk1yrpTNFy(dot)1MLOlb(at)seznam(dot)cz
> of an apparent error in our WIN1250 -> LATIN2 conversion.

Attached is an updated patch (against today's HEAD) showing proposed
changes to bring cyrillic_and_mic.c and latin2_and_win1250.c into sync
with the Unicode Consortium's conversion data.

In addition, I've attached the C program I used to generate the proposed
new conversion tables from the Unicode/*.map files, a simple SQL script
to print out the conversion behavior for the affected conversions, and
a diff of the script's output between 9.5 and the proposed patch.

While the changes in the WIN1250 <-> LATIN2 conversions just amount to
removal of some translations that seem to have no basis in reality, the
changes in the Cyrillic mappings are quite a bit more extensive. It would
be good if we could get those checked by some native Russian speakers.

regards, tom lane