diff --git a/src/backend/catalog/partition.c b/src/backend/catalog/partition.c
index ad95b1bc55..8c9a373f1f 100644
--- a/src/backend/catalog/partition.c
+++ b/src/backend/catalog/partition.c
@@ -639,12 +639,14 @@ partition_bounds_equal(PartitionKey key,
 					continue;
 			}
 
-			/* Compare the actual values */
-			cmpval = DatumGetInt32(FunctionCall2Coll(&key->partsupfunc[j],
-													 key->partcollation[j],
-													 b1->datums[i][j],
-													 b2->datums[i][j]));
-			if (cmpval != 0)
+			/*
+			 * Compare the actual values; note that we do not invoke the
+			 * partitioning specific comparison operator here, because we
+			 * could be in an aborted transaction.
+			 */
+			if (!datumIsEqual(b1->datums[i][j], b2->datums[i][j],
+							  key->parttypbyval[j],
+							  key->parttyplen[j]))
 				return false;
 		}
 
diff --git a/src/backend/utils/adt/datum.c b/src/backend/utils/adt/datum.c
index 535e4277cc..071a7d4db1 100644
--- a/src/backend/utils/adt/datum.c
+++ b/src/backend/utils/adt/datum.c
@@ -209,6 +209,10 @@ datumTransfer(Datum value, bool typByVal, int typLen)
  * of say the representation of zero in one's complement arithmetic).
  * Also, it will probably not give the answer you want if either
  * datum has been "toasted".
+ *
+ * Do not try to make this any smarter than it currently is with respect
+ * to "toasted" datums, because some of the callers could be working in the
+ * context of an aborted transaction.
  *-------------------------------------------------------------------------
  */
 bool