Correctly set t_self for heap tuples in expand_tuple

adunstan · adunstan · commit 372102b81dd0 · 2018-10-24T10:57:35.000-04:00
Commit 16828d5 incorrectly set an invalid pointer for t_self for heap tuples. This patch correctly copies it from the source tuple, and includes a regression test that relies on it being set correctly. Backpatch to release 11. Fixes bug #15448 reported by Tillmann Schulz Diagnosis and test case by Amit Langote
diff --git a/src/backend/access/common/heaptuple.c b/src/backend/access/common/heaptuple.c
@@ -893,7 +893,7 @@ expand_tuple(HeapTuple *targetHeapTuple,
 			= (HeapTupleHeader) ((char *) *targetHeapTuple + HEAPTUPLESIZE);
 		(*targetHeapTuple)->t_len = len;
 		(*targetHeapTuple)->t_tableOid = sourceTuple->t_tableOid;
-		ItemPointerSetInvalid(&((*targetHeapTuple)->t_self));
+		(*targetHeapTuple)->t_self = sourceTuple->t_self;
 
 		targetTHeader->t_infomask = sourceTHeader->t_infomask;
 		targetTHeader->t_hoff = hoff;
diff --git a/src/test/regress/expected/fast_default.out b/src/test/regress/expected/fast_default.out
@@ -727,7 +727,17 @@ SELECT * FROM t;
 (1 row)
 
 DROP TABLE t;
+-- make sure expanded tuple has correct self pointer
+-- it will be required by the RI tigger doing the cascading delete
+CREATE TABLE leader (a int PRIMARY KEY, b int);
+CREATE TABLE follower (a int REFERENCES leader ON DELETE CASCADE, b int);
+INSERT INTO leader VALUES (1, 1), (2, 2);
+ALTER TABLE leader ADD c int;
+ALTER TABLE leader DROP c;
+DELETE FROM leader;
 -- cleanup
+DROP TABLE follower;
+DROP TABLE leader;
 DROP FUNCTION test_trigger();
 DROP TABLE t1;
 DROP FUNCTION set(name);
diff --git a/src/test/regress/sql/fast_default.sql b/src/test/regress/sql/fast_default.sql
@@ -471,7 +471,19 @@ UPDATE t SET y = 2;
 SELECT * FROM t;
 DROP TABLE t;
 
+-- make sure expanded tuple has correct self pointer
+-- it will be required by the RI tigger doing the cascading delete
+
+CREATE TABLE leader (a int PRIMARY KEY, b int);
+CREATE TABLE follower (a int REFERENCES leader ON DELETE CASCADE, b int);
+INSERT INTO leader VALUES (1, 1), (2, 2);
+ALTER TABLE leader ADD c int;
+ALTER TABLE leader DROP c;
+DELETE FROM leader;
+
 -- cleanup
+DROP TABLE follower;
+DROP TABLE leader;
 DROP FUNCTION test_trigger();
 DROP TABLE t1;
 DROP FUNCTION set(name);
