Avoid valgrind complaint about write() of uninitalized bytes. LogicalTapeFreeze() may write out its first block when it is dirty but not full, and then immediately read the first block back in from its BufFile as a BLCKSZ-width block. This can only occur in rare cases where very few tuples were written out, which is currently only possible with parallel external tuplesorts. To avoid valgrind complaints, tell it to treat the tail of logtape.c's buffer as defined.
Commit 9da0cc35284bdbe8d442d732963303ff0e0a40bc exposed this problem but did not create it. LogicalTapeFreeze() has always tended to write out some amount of garbage bytes, but previously never wrote less than one block of data in total, so the problem was masked. Per buildfarm members lousyjack and skink. Peter Geoghegan, based on a suggestion from Tom Lane and me. Some comment revisions by me. Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/9fafa413ac602624e10f61ef44a20c17029d43d8 Modified Files -------------- src/backend/utils/sort/logtape.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)
