Formerly, Catalog.pm turned a C array type declaration in the catalog
header files into a SQL type, e.g., 'foo[]'.  Along the way, genbki.pl
turned this into '_foo' for the purpose of type lookups, but wrote 'foo[]'
to postgres.bki.  During bootstrap, bootscanner.l had to have a special
case rule to tokenize this, and then MapArrayTypeName() would turn 'foo[]'
into '_foo' one more time.

This seems unnecessarily complicated, especially since nobody cares that
much about the readability of postgres.bki.  Instead, make Catalog.pm
convert the C declaration into '_foo' to start with, and preserve that
representation of the type name throughout bootstrap data processing.
Then rip out the special-case code in bootscanner.l and bootstrap.c.

This changes postgres.bki to the extent that array fields are now
declared like
  proconfig = _text ,
rather than
  proconfig = text[] ,

No documentation update, since the SGML docs didn't mention any of this
in the first place, and it's all pretty transparent to writers of
catalog header files anyway.

John Naylor

Discussion: https://postgr.es/m/CAJVSVGUNao=-Q2-vAN3PYcdF5tnL5JAHwGwzZGuYHtq+Mk_9ng@mail.gmail.com