amcheck: In verify_heapam, allows tuples with xmin 0.

robertmhaas · robertmhaas · commit b7cea58822c6 · 2023-03-28T16:16:53.000-04:00
Commit e88754a caused that case to be reported as corruption, but Peter Geoghegan pointed out that it can legitimately happen in the case of a speculative insertion that aborts, so we'd better not flag it as corruption after all. Back-patch to v14, like the commit that introduced the issue. Discussion: http://postgr.es/m/CAH2-WzmEabzcPTxSY-NXKH6Qt3FkAPYHGQSe2PtvGgj17ZQkCw@mail.gmail.com
diff --git a/contrib/amcheck/verify_heapam.c b/contrib/amcheck/verify_heapam.c
@@ -1032,8 +1032,7 @@ check_tuple_visibility(HeapCheckContext *ctx, bool *xmin_commit_status_ok,
 	switch (get_xid_status(xmin, ctx, &xmin_status))
 	{
 		case XID_INVALID:
-			report_corruption(ctx,
-							  pstrdup("xmin is invalid"));
+			/* Could be the result of a speculative insertion that aborted. */
 			return false;
 		case XID_BOUNDS_OK:
 			*xmin_commit_status_ok = true;
