See:
Subject: [HACKERS] bugs with certain Asian multibyte charsets
From: Tatsuo Ishii <ishii@sraoss.co.jp>
To: pgsql-hackers@postgresql.org
Date: Sat, 24 Dec 2005 18:25:33 +0900 (JST)
for more details.
equal: if strcoll claims two strings are equal, check it with strcmp, and
sort according to strcmp if not identical. This fixes inconsistent
behavior under glibc's hu_HU locale, and probably under some other locales
as well. Also, take advantage of the now-well-defined behavior to speed up
texteq, textne, bpchareq, bpcharne: they may as well just do a bitwise
comparison and not bother with strcoll at all.
NOTE: affected databases may need to REINDEX indexes on text columns to be
sure they are self-consistent.
very narrow window in which SimpleLruReadPage or SimpleLruWritePage could
think that I/O was needed when it wasn't (and indeed the buffer had already
been assigned to another page). This would result in an Assert failure if
Asserts were enabled, and probably in silent data corruption if not.
Reported independently by Jim Nasby and Robert Creager.
I intend a more extensive fix when 8.2 development starts, but this is a
reasonably low-impact patch for the existing branches.
for an outer join; symptom is bogus error "RIGHT JOIN is only supported with
merge-joinable join conditions". Problem was that select_mergejoin_clauses
did its tests in the wrong order. We need to force left join not right join
for a merge join when there are non-mergeable join clauses; but the test for
this only accounted for mergejoinability of the clause operator, and not
whether the left and right Vars were of the proper relations. Per report
from Jean-Pierre Pelletier.
the wrong buffer dirty when trying to kill a dead index entry that's on
a page after the one it started on. No risk of data corruption, just
inefficiency, but still a bug.
checked that the pointer is actually word-aligned. Casting a non-aligned
pointer to int32* is technically illegal per the C spec, and some recent
versions of gcc actually generate bad code for the memset() when given
such a pointer. Per report from Andrew Morrow.
and prepare tests, which cause intermittent failures in parallel test
mode. Back-port of fix originally applied to 8.0 and 7.4 branches;
the problems do not appear to exist in 7.2 branch but they do occur
in 7.3. Per buildfarm results.
copying/converting the new value, which meant that it failed badly on
"var := var" if var is of pass-by-reference type. Fix this and a similar
hazard in exec_move_row(); not sure that the latter can manifest before
8.0, but patch it all the way back anyway. Per report from Dave Chapeskie.
if geqo_rand() returns exactly 1.0, resulting in failure due to indexing
off the end of the pool array. Also, since this is using inexact float math,
it seems wise to guard against roundoff error producing values slightly
outside the expected range. Per report from bug@zedware.org.
to just around the bare recv() call that gets a command from the client.
The former placement in PostgresMain was unsafe because the intermediate
processing layers (especially SSL) use facilities such as malloc that are
not necessarily re-entrant. Per report from counterstorm.com.
to columns of an RTE that was a function returning RECORD with a column
definition list. Apparently no one has tried to use non-default typmod
with a function returning RECORD before.
if they are two-byte multibyte characters. Same thing can be happen
if octet_length(multibyte_chars) == n where n is char(n).
Long standing bug since 7.3 days. Per report and fix from Yoshiyuki Asaba.