3849ce5b30
Previously, in the path for non-deterministic collations, the code
assumed that bsize==rsize. That assumption seems to be true for ICU,
and all non-deterministic collations are ICU, so it's not known to be
an actual bug.
The only known place where bsize may not equal rsize is in the libc
provider, where strxfrm() can return an upper bound of the size needed
to store the result. That means the initial call to determine the
buffer size (with dest==NULL, n==0) could return a larger number than
the actual call with an adequate dest buffer. That's OK, because libc
locales are always deterministic.
Commit 679c5084cf partially fixed the assumption, but missed this
part. Fix it, and add a more prominent documentation note.
Reviewed-by: Haibo Yan <tristan.yim@gmail.com>
Discussion: https://postgr.es/m/CABXr29Hb31nkj1g2Jmk+1BhAm=3ecGs_pWy4tU++j8CQBnbMxQ@mail.gmail.com
Backpatch-through: 16
PostgreSQL Database Management System
This directory contains the source code distribution of the PostgreSQL database management system.
PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings.
Copyright and license information can be found in the file COPYRIGHT.
General documentation about this version of PostgreSQL can be found at https://www.postgresql.org/docs/19/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/19/installation.html.
The latest version of this software, and related software, may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.