16edc1b94f
Two or more constants can have the same location. We handled this
correctly for non squashed constants, but failed to do it if squashed
(resulting in out-of-bounds memory access), because the code structure
became broken by commit 0f65f3eec4: we failed to update 'last_loc'
correctly when skipping these squashed constants.
The simplest fix seems to be to get rid of 'last_loc' altogether -- in
hindsight, it's quite pointless. Also, when ignoring a constant because
of this, make sure to fulfill fill_in_constant_lengths's duty of setting
its length to -1.
Lastly, we can use == instead of <= because the locations have been
sorted beforehand, so the < case cannot arise.
Co-authored-by: Sami Imseih <samimseih@gmail.com>
Co-authored-by: Dmitry Dolgov <9erthalion6@gmail.com>
Reported-by: Konstantin Knizhnik <knizhnik@garret.ru>
Backpatch-through: 18
Discussion: https://www.postgresql.org/message-id/2b91e358-0d99-43f7-be44-d2d4dbce37b3%40garret.ru
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.
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