From d12d864634ec2d6445397362844609ab7528106e Mon Sep 17 00:00:00 2001 From: "Andrei V. Lepikhov" Date: Wed, 15 Apr 2026 14:41:51 +0200 Subject: [PATCH] test_tidstore: Stabilize regression tests by sorting offsets. TidStoreSetBlockOffsets() requires its offsets array to be strictly ascending and asserts this precondition. In test_tidstore, we were passing random offset numbers deduplicated by a DISTINCT clause in an array_agg() call directly to the do_set_block_offsets() test harness. However, DISTINCT without an ORDER BY clause does not guarantee sorted results according to the SQL standard. Fix this by sorting the offsets in-place inside do_set_block_offsets() before calling TidStoreSetBlockOffsets(). While this assertion failure is not observed during regular regression tests because they use queries simple enough that the optimizer consistently chooses plans yielding sorted results, it makes sense to stabilize the test. The failure could theoretically occur depending on the optimizer's plan choice, and has been reported when experimenting with certain third-party extensions. Backpatch to v17, where tid_store was introduced, to ensure extension development on stable branches does not hit this assertion. Reported-by: Andrei Lepikhov Author: Andrei Lepikhov Discussion: https://postgr.es/m/b97f1850-fc7b-43c4-9b04-4e97bb9e7dc0@gmail.com --- src/test/modules/test_tidstore/test_tidstore.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/src/test/modules/test_tidstore/test_tidstore.c b/src/test/modules/test_tidstore/test_tidstore.c index c9a035fa494..bfc40bce24c 100644 --- a/src/test/modules/test_tidstore/test_tidstore.c +++ b/src/test/modules/test_tidstore/test_tidstore.c @@ -75,6 +75,19 @@ itemptr_cmp(const void *left, const void *right) return 0; } +static int +offsetnumber_cmp(const void *a, const void *b) +{ + OffsetNumber l = *(const OffsetNumber *) a; + OffsetNumber r = *(const OffsetNumber *) b; + + if (l < r) + return -1; + else if (l > r) + return 1; + return 0; +} + /* * Create a TidStore. If shared is false, the tidstore is created * on TopMemoryContext, otherwise on DSA. Although the tidstore @@ -178,6 +191,9 @@ do_set_block_offsets(PG_FUNCTION_ARGS) noffs = ArrayGetNItems(ARR_NDIM(ta), ARR_DIMS(ta)); offs = ((OffsetNumber *) ARR_DATA_PTR(ta)); + /* TidStoreSetBlockOffsets() requires offsets to be strictly ascending. */ + qsort(offs, noffs, sizeof(OffsetNumber), offsetnumber_cmp); + /* Set TIDs in the store */ TidStoreLockExclusive(tidstore); TidStoreSetBlockOffsets(tidstore, blkno, offs, noffs); -- 2.54.0