1 files changed, 21 insertions, 6 deletions

diff --git a/src/backend/access/common/heaptuple.c b/src/backend/access/common/heaptuple.c
index acd5da4ccf8..969d1028cae 100644
--- a/src/backend/access/common/heaptuple.c
+++ b/src/backend/access/common/heaptuple.c
@@ -1452,9 +1452,11 @@ heap_freetuple(HeapTuple htup)
 MinimalTuple
 heap_form_minimal_tuple(TupleDesc tupleDescriptor,
 						const Datum *values,
-						const bool *isnull)
+						const bool *isnull,
+						Size extra)
 {
 	MinimalTuple tuple;			/* return tuple */
+	char	   *mem;
 	Size		len,
 				data_len;
 	int			hoff;
@@ -1462,6 +1464,8 @@ heap_form_minimal_tuple(TupleDesc tupleDescriptor,
 	int			numberOfAttributes = tupleDescriptor->natts;
 	int			i;
 
+	Assert(extra == MAXALIGN(extra));
+
 	if (numberOfAttributes > MaxTupleAttributeNumber)
 		ereport(ERROR,
 				(errcode(ERRCODE_TOO_MANY_COLUMNS),
@@ -1497,7 +1501,9 @@ heap_form_minimal_tuple(TupleDesc tupleDescriptor,
 	/*
 	 * Allocate and zero the space needed.
 	 */
-	tuple = (MinimalTuple) palloc0(len);
+	mem = palloc0(len + extra);
+	memset(mem, 0, extra);
+	tuple = (MinimalTuple) (mem + extra);
 
 	/*
 	 * And fill in the information.
@@ -1533,11 +1539,15 @@ heap_free_minimal_tuple(MinimalTuple mtup)
  * The result is allocated in the current memory context.
  */
 MinimalTuple
-heap_copy_minimal_tuple(MinimalTuple mtup)
+heap_copy_minimal_tuple(MinimalTuple mtup, Size extra)
 {
 	MinimalTuple result;
+	char	   *mem;
 
-	result = (MinimalTuple) palloc(mtup->t_len);
+	Assert(extra == MAXALIGN(extra));
+	mem = palloc(mtup->t_len + extra);
+	memset(mem, 0, extra);
+	result = (MinimalTuple) (mem + extra);
 	memcpy(result, mtup, mtup->t_len);
 	return result;
 }
@@ -1574,15 +1584,20 @@ heap_tuple_from_minimal_tuple(MinimalTuple mtup)
  * The result is allocated in the current memory context.
  */
 MinimalTuple
-minimal_tuple_from_heap_tuple(HeapTuple htup)
+minimal_tuple_from_heap_tuple(HeapTuple htup, Size extra)
 {
 	MinimalTuple result;
+	char	   *mem;
 	uint32		len;
 
+	Assert(extra == MAXALIGN(extra));
 	Assert(htup->t_len > MINIMAL_TUPLE_OFFSET);
 	len = htup->t_len - MINIMAL_TUPLE_OFFSET;
-	result = (MinimalTuple) palloc(len);
+	mem = palloc(len + extra);
+	memset(mem, 0, extra);
+	result = (MinimalTuple) (mem + extra);
 	memcpy(result, (char *) htup->t_data + MINIMAL_TUPLE_OFFSET, len);
+
 	result->t_len = len;
 	return result;
 }