f0c2a5bba6
RestoreGUCState applied InitializeOneGUCOption to already-live GUC entries, causing any malloc'd subsidiary data to be forgotten. We do want the effect of resetting the GUC to its compiled-in default, and InitializeOneGUCOption seems like the best way to do that, so add code to free any existing subsidiary data beforehand. The interaction between can_skip_gucvar, SerializeGUCState, and RestoreGUCState is way more subtle than their opaque comments would suggest to an unwary reader. Rewrite and enlarge the comments to try to make it clearer what's happening. Remove a long-obsolete assertion in read_nondefault_variables: the behavior of set_config_option hasn't depended on IsInitProcessingMode since f5d9698a8 installed a better way of controlling it. Although this is fixing a clear memory leak, the leak is quite unlikely to involve any large amount of data, and it can only happen once in the lifetime of a worker process. So it seems unnecessary to take any risk of back-patching. Discussion: https://postgr.es/m/4105247.1616174862@sss.pgh.pa.us
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. PostgreSQL has many language interfaces, many of which are listed here: https://www.postgresql.org/download/ See the file INSTALL for instructions on how to build and install PostgreSQL. That file also lists supported operating systems and hardware platforms and contains information regarding any other software packages that are required to build or run the PostgreSQL system. Copyright and license information can be found in the file COPYRIGHT. A comprehensive documentation set is included in this distribution; it can be read as described in the installation instructions. The latest version of this software may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.