Fix various instances of undefined behavior Mostly this involves checking for NULL pointer before doing operations that add a non-zero offset.
The exception is an overflow warning in heap_fetch_toast_slice(). This was caused by unneeded parentheses forcing an expression to be evaluated to a negative integer, which then got cast to size_t. Per clang 21 undefined behavior sanitizer. Backpatch to all supported versions. Co-authored-by: Alexander Lakhin <[email protected]> Reported-by: Alexander Lakhin <[email protected]> Discussion: https://postgr.es/m/[email protected] Backpatch-through: 14 Branch ------ REL_18_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/b5e1cd2fdca1ad48982e376c0d22f468e862933c Modified Files -------------- contrib/pg_trgm/trgm_gist.c | 5 ++++- src/backend/access/heap/heaptoast.c | 2 +- src/backend/utils/adt/multirangetypes.c | 5 +++-- src/backend/utils/sort/sharedtuplestore.c | 3 ++- 4 files changed, 10 insertions(+), 5 deletions(-)
