Change tupledesc->attrs[n] to TupleDescAttr(tupledesc, n).

This is a mechanical change in preparation for a later commit that
will change the layout of TupleDesc.  Introducing a macro to abstract
the details of where attributes are stored will allow us to change
that in separate step and revise it in future.

Author: Thomas Munro, editorialized by Andres Freund
Reviewed-By: Andres Freund
Discussion: https://postgr.es/m/CAEepm=0ZtQ-SpsgCyzzYpsXS6e=kZWqk3g5Ygn3MDV7A8dabUA@mail.gmail.com

8 files changed, 110 insertions, 80 deletions

diff --git a/src/backend/utils/adt/json.c b/src/backend/utils/adt/json.c
index 4dd7d977e8a..1ddb42b4d08 100644
--- a/src/backend/utils/adt/json.c
+++ b/src/backend/utils/adt/json.c
@@ -1714,15 +1714,16 @@ composite_to_json(Datum composite, StringInfo result, bool use_line_feeds)
 		char	   *attname;
 		JsonTypeCategory tcategory;
 		Oid			outfuncoid;
+		Form_pg_attribute att = TupleDescAttr(tupdesc, i);
 
-		if (tupdesc->attrs[i]->attisdropped)
+		if (att->attisdropped)
 			continue;
 
 		if (needsep)
 			appendStringInfoString(result, sep);
 		needsep = true;
 
-		attname = NameStr(tupdesc->attrs[i]->attname);
+		attname = NameStr(att->attname);
 		escape_json(result, attname);
 		appendStringInfoChar(result, ':');
 
@@ -1734,8 +1735,7 @@ composite_to_json(Datum composite, StringInfo result, bool use_line_feeds)
 			outfuncoid = InvalidOid;
 		}
 		else
-			json_categorize_type(tupdesc->attrs[i]->atttypid,
-								 &tcategory, &outfuncoid);
+			json_categorize_type(att->atttypid, &tcategory, &outfuncoid);
 
 		datum_to_json(val, isnull, result, tcategory, outfuncoid, false);
 	}
diff --git a/src/backend/utils/adt/jsonb.c b/src/backend/utils/adt/jsonb.c
index 49f41f9f999..1eb7f3d6f9d 100644
--- a/src/backend/utils/adt/jsonb.c
+++ b/src/backend/utils/adt/jsonb.c
@@ -1075,11 +1075,12 @@ composite_to_jsonb(Datum composite, JsonbInState *result)
 		JsonbTypeCategory tcategory;
 		Oid			outfuncoid;
 		JsonbValue	v;
+		Form_pg_attribute att = TupleDescAttr(tupdesc, i);
 
-		if (tupdesc->attrs[i]->attisdropped)
+		if (att->attisdropped)
 			continue;
 
-		attname = NameStr(tupdesc->attrs[i]->attname);
+		attname = NameStr(att->attname);
 
 		v.type = jbvString;
 		/* don't need checkStringLen here - can't exceed maximum name length */
@@ -1096,8 +1097,7 @@ composite_to_jsonb(Datum composite, JsonbInState *result)
 			outfuncoid = InvalidOid;
 		}
 		else
-			jsonb_categorize_type(tupdesc->attrs[i]->atttypid,
-								  &tcategory, &outfuncoid);
+			jsonb_categorize_type(att->atttypid, &tcategory, &outfuncoid);
 
 		datum_to_jsonb(val, isnull, result, tcategory, outfuncoid, false);
 	}
diff --git a/src/backend/utils/adt/jsonfuncs.c b/src/backend/utils/adt/jsonfuncs.c
index 4779e74895c..d92ffa83d94 100644
--- a/src/backend/utils/adt/jsonfuncs.c
+++ b/src/backend/utils/adt/jsonfuncs.c
@@ -3087,7 +3087,7 @@ populate_record(TupleDesc tupdesc,
 
 	for (i = 0; i < ncolumns; ++i)
 	{
-		Form_pg_attribute att = tupdesc->attrs[i];
+		Form_pg_attribute att = TupleDescAttr(tupdesc, i);
 		char	   *colname = NameStr(att->attname);
 		JsValue		field = {0};
 		bool		found;
diff --git a/src/backend/utils/adt/orderedsetaggs.c b/src/backend/utils/adt/orderedsetaggs.c
index 8502fcfc82e..25905a3287e 100644
--- a/src/backend/utils/adt/orderedsetaggs.c
+++ b/src/backend/utils/adt/orderedsetaggs.c
@@ -1125,13 +1125,15 @@ hypothetical_check_argtypes(FunctionCallInfo fcinfo, int nargs,
 	/* check that we have an int4 flag column */
 	if (!tupdesc ||
 		(nargs + 1) != tupdesc->natts ||
-		tupdesc->attrs[nargs]->atttypid != INT4OID)
+		TupleDescAttr(tupdesc, nargs)->atttypid != INT4OID)
 		elog(ERROR, "type mismatch in hypothetical-set function");
 
 	/* check that direct args match in type with aggregated args */
 	for (i = 0; i < nargs; i++)
 	{
-		if (get_fn_expr_argtype(fcinfo->flinfo, i + 1) != tupdesc->attrs[i]->atttypid)
+		Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
+
+		if (get_fn_expr_argtype(fcinfo->flinfo, i + 1) != attr->atttypid)
 			elog(ERROR, "type mismatch in hypothetical-set function");
 	}
 }
diff --git a/src/backend/utils/adt/rowtypes.c b/src/backend/utils/adt/rowtypes.c
index 44acd13c6b1..98fe00ff394 100644
--- a/src/backend/utils/adt/rowtypes.c
+++ b/src/backend/utils/adt/rowtypes.c
@@ -159,12 +159,13 @@ record_in(PG_FUNCTION_ARGS)
 
 	for (i = 0; i < ncolumns; i++)
 	{
+		Form_pg_attribute att = TupleDescAttr(tupdesc, i);
 		ColumnIOData *column_info = &my_extra->columns[i];
-		Oid			column_type = tupdesc->attrs[i]->atttypid;
+		Oid			column_type = att->atttypid;
 		char	   *column_data;
 
 		/* Ignore dropped columns in datatype, but fill with nulls */
-		if (tupdesc->attrs[i]->attisdropped)
+		if (att->attisdropped)
 		{
 			values[i] = (Datum) 0;
 			nulls[i] = true;
@@ -252,7 +253,7 @@ record_in(PG_FUNCTION_ARGS)
 		values[i] = InputFunctionCall(&column_info->proc,
 									  column_data,
 									  column_info->typioparam,
-									  tupdesc->attrs[i]->atttypmod);
+									  att->atttypmod);
 
 		/*
 		 * Prep for next column
@@ -367,15 +368,16 @@ record_out(PG_FUNCTION_ARGS)
 
 	for (i = 0; i < ncolumns; i++)
 	{
+		Form_pg_attribute att = TupleDescAttr(tupdesc, i);
 		ColumnIOData *column_info = &my_extra->columns[i];
-		Oid			column_type = tupdesc->attrs[i]->atttypid;
+		Oid			column_type = att->atttypid;
 		Datum		attr;
 		char	   *value;
 		char	   *tmp;
 		bool		nq;
 
 		/* Ignore dropped columns in datatype */
-		if (tupdesc->attrs[i]->attisdropped)
+		if (att->attisdropped)
 			continue;
 
 		if (needComma)
@@ -519,7 +521,7 @@ record_recv(PG_FUNCTION_ARGS)
 	validcols = 0;
 	for (i = 0; i < ncolumns; i++)
 	{
-		if (!tupdesc->attrs[i]->attisdropped)
+		if (!TupleDescAttr(tupdesc, i)->attisdropped)
 			validcols++;
 	}
 	if (usercols != validcols)
@@ -531,8 +533,9 @@ record_recv(PG_FUNCTION_ARGS)
 	/* Process each column */
 	for (i = 0; i < ncolumns; i++)
 	{
+		Form_pg_attribute att = TupleDescAttr(tupdesc, i);
 		ColumnIOData *column_info = &my_extra->columns[i];
-		Oid			column_type = tupdesc->attrs[i]->atttypid;
+		Oid			column_type = att->atttypid;
 		Oid			coltypoid;
 		int			itemlen;
 		StringInfoData item_buf;
@@ -540,7 +543,7 @@ record_recv(PG_FUNCTION_ARGS)
 		char		csave;
 
 		/* Ignore dropped columns in datatype, but fill with nulls */
-		if (tupdesc->attrs[i]->attisdropped)
+		if (att->attisdropped)
 		{
 			values[i] = (Datum) 0;
 			nulls[i] = true;
@@ -605,7 +608,7 @@ record_recv(PG_FUNCTION_ARGS)
 		values[i] = ReceiveFunctionCall(&column_info->proc,
 										bufptr,
 										column_info->typioparam,
-										tupdesc->attrs[i]->atttypmod);
+										att->atttypmod);
 
 		if (bufptr)
 		{
@@ -712,20 +715,21 @@ record_send(PG_FUNCTION_ARGS)
 	validcols = 0;
 	for (i = 0; i < ncolumns; i++)
 	{
-		if (!tupdesc->attrs[i]->attisdropped)
+		if (!TupleDescAttr(tupdesc, i)->attisdropped)
 			validcols++;
 	}
 	pq_sendint(&buf, validcols, 4);
 
 	for (i = 0; i < ncolumns; i++)
 	{
+		Form_pg_attribute att = TupleDescAttr(tupdesc, i);
 		ColumnIOData *column_info = &my_extra->columns[i];
-		Oid			column_type = tupdesc->attrs[i]->atttypid;
+		Oid			column_type = att->atttypid;
 		Datum		attr;
 		bytea	   *outputbytes;
 
 		/* Ignore dropped columns in datatype */
-		if (tupdesc->attrs[i]->attisdropped)
+		if (att->attisdropped)
 			continue;
 
 		pq_sendint(&buf, column_type, sizeof(Oid));
@@ -873,18 +877,20 @@ record_cmp(FunctionCallInfo fcinfo)
 	i1 = i2 = j = 0;
 	while (i1 < ncolumns1 || i2 < ncolumns2)
 	{
+		Form_pg_attribute att1;
+		Form_pg_attribute att2;
 		TypeCacheEntry *typentry;
 		Oid			collation;
 
 		/*
 		 * Skip dropped columns
 		 */
-		if (i1 < ncolumns1 && tupdesc1->attrs[i1]->attisdropped)
+		if (i1 < ncolumns1 && TupleDescAttr(tupdesc1, i1)->attisdropped)
 		{
 			i1++;
 			continue;
 		}
-		if (i2 < ncolumns2 && tupdesc2->attrs[i2]->attisdropped)
+		if (i2 < ncolumns2 && TupleDescAttr(tupdesc2, i2)->attisdropped)
 		{
 			i2++;
 			continue;
@@ -892,24 +898,26 @@ record_cmp(FunctionCallInfo fcinfo)
 		if (i1 >= ncolumns1 || i2 >= ncolumns2)
 			break;				/* we'll deal with mismatch below loop */
 
+		att1 = TupleDescAttr(tupdesc1, i1);
+		att2 = TupleDescAttr(tupdesc2, i2);
+
 		/*
 		 * Have two matching columns, they must be same type
 		 */
-		if (tupdesc1->attrs[i1]->atttypid !=
-			tupdesc2->attrs[i2]->atttypid)
+		if (att1->atttypid != att2->atttypid)
 			ereport(ERROR,
 					(errcode(ERRCODE_DATATYPE_MISMATCH),
 					 errmsg("cannot compare dissimilar column types %s and %s at record column %d",
-							format_type_be(tupdesc1->attrs[i1]->atttypid),
-							format_type_be(tupdesc2->attrs[i2]->atttypid),
+							format_type_be(att1->atttypid),
+							format_type_be(att2->atttypid),
 							j + 1)));
 
 		/*
 		 * If they're not same collation, we don't complain here, but the
 		 * comparison function might.
 		 */
-		collation = tupdesc1->attrs[i1]->attcollation;
-		if (collation != tupdesc2->attrs[i2]->attcollation)
+		collation = att1->attcollation;
+		if (collation != att2->attcollation)
 			collation = InvalidOid;
 
 		/*
@@ -917,9 +925,9 @@ record_cmp(FunctionCallInfo fcinfo)
 		 */
 		typentry = my_extra->columns[j].typentry;
 		if (typentry == NULL ||
-			typentry->type_id != tupdesc1->attrs[i1]->atttypid)
+			typentry->type_id != att1->atttypid)
 		{
-			typentry = lookup_type_cache(tupdesc1->attrs[i1]->atttypid,
+			typentry = lookup_type_cache(att1->atttypid,
 										 TYPECACHE_CMP_PROC_FINFO);
 			if (!OidIsValid(typentry->cmp_proc_finfo.fn_oid))
 				ereport(ERROR,
@@ -1111,6 +1119,8 @@ record_eq(PG_FUNCTION_ARGS)
 	i1 = i2 = j = 0;
 	while (i1 < ncolumns1 || i2 < ncolumns2)
 	{
+		Form_pg_attribute att1;
+		Form_pg_attribute att2;
 		TypeCacheEntry *typentry;
 		Oid			collation;
 		FunctionCallInfoData locfcinfo;
@@ -1119,12 +1129,12 @@ record_eq(PG_FUNCTION_ARGS)
 		/*
 		 * Skip dropped columns
 		 */
-		if (i1 < ncolumns1 && tupdesc1->attrs[i1]->attisdropped)
+		if (i1 < ncolumns1 && TupleDescAttr(tupdesc1, i1)->attisdropped)
 		{
 			i1++;
 			continue;
 		}
-		if (i2 < ncolumns2 && tupdesc2->attrs[i2]->attisdropped)
+		if (i2 < ncolumns2 && TupleDescAttr(tupdesc2, i2)->attisdropped)
 		{
 			i2++;
 			continue;
@@ -1132,24 +1142,26 @@ record_eq(PG_FUNCTION_ARGS)
 		if (i1 >= ncolumns1 || i2 >= ncolumns2)
 			break;				/* we'll deal with mismatch below loop */
 
+		att1 = TupleDescAttr(tupdesc1, i1);
+		att2 = TupleDescAttr(tupdesc2, i2);
+
 		/*
 		 * Have two matching columns, they must be same type
 		 */
-		if (tupdesc1->attrs[i1]->atttypid !=
-			tupdesc2->attrs[i2]->atttypid)
+		if (att1->atttypid != att2->atttypid)
 			ereport(ERROR,
 					(errcode(ERRCODE_DATATYPE_MISMATCH),
 					 errmsg("cannot compare dissimilar column types %s and %s at record column %d",
-							format_type_be(tupdesc1->attrs[i1]->atttypid),
-							format_type_be(tupdesc2->attrs[i2]->atttypid),
+							format_type_be(att1->atttypid),
+							format_type_be(att2->atttypid),
 							j + 1)));
 
 		/*
 		 * If they're not same collation, we don't complain here, but the
 		 * equality function might.
 		 */
-		collation = tupdesc1->attrs[i1]->attcollation;
-		if (collation != tupdesc2->attrs[i2]->attcollation)
+		collation = att1->attcollation;
+		if (collation != att2->attcollation)
 			collation = InvalidOid;
 
 		/*
@@ -1157,9 +1169,9 @@ record_eq(PG_FUNCTION_ARGS)
 		 */
 		typentry = my_extra->columns[j].typentry;
 		if (typentry == NULL ||
-			typentry->type_id != tupdesc1->attrs[i1]->atttypid)
+			typentry->type_id != att1->atttypid)
 		{
-			typentry = lookup_type_cache(tupdesc1->attrs[i1]->atttypid,
+			typentry = lookup_type_cache(att1->atttypid,
 										 TYPECACHE_EQ_OPR_FINFO);
 			if (!OidIsValid(typentry->eq_opr_finfo.fn_oid))
 				ereport(ERROR,
@@ -1370,15 +1382,18 @@ record_image_cmp(FunctionCallInfo fcinfo)
 	i1 = i2 = j = 0;
 	while (i1 < ncolumns1 || i2 < ncolumns2)
 	{
+		Form_pg_attribute att1;
+		Form_pg_attribute att2;
+
 		/*
 		 * Skip dropped columns
 		 */
-		if (i1 < ncolumns1 && tupdesc1->attrs[i1]->attisdropped)
+		if (i1 < ncolumns1 && TupleDescAttr(tupdesc1, i1)->attisdropped)
 		{
 			i1++;
 			continue;
 		}
-		if (i2 < ncolumns2 && tupdesc2->attrs[i2]->attisdropped)
+		if (i2 < ncolumns2 && TupleDescAttr(tupdesc2, i2)->attisdropped)
 		{
 			i2++;
 			continue;
@@ -1386,24 +1401,25 @@ record_image_cmp(FunctionCallInfo fcinfo)
 		if (i1 >= ncolumns1 || i2 >= ncolumns2)
 			break;				/* we'll deal with mismatch below loop */
 
+		att1 = TupleDescAttr(tupdesc1, i1);
+		att2 = TupleDescAttr(tupdesc2, i2);
+
 		/*
 		 * Have two matching columns, they must be same type
 		 */
-		if (tupdesc1->attrs[i1]->atttypid !=
-			tupdesc2->attrs[i2]->atttypid)
+		if (att1->atttypid != att2->atttypid)
 			ereport(ERROR,
 					(errcode(ERRCODE_DATATYPE_MISMATCH),
 					 errmsg("cannot compare dissimilar column types %s and %s at record column %d",
-							format_type_be(tupdesc1->attrs[i1]->atttypid),
-							format_type_be(tupdesc2->attrs[i2]->atttypid),
+							format_type_be(att1->atttypid),
+							format_type_be(att2->atttypid),
 							j + 1)));
 
 		/*
 		 * The same type should have the same length (or both should be
 		 * variable).
 		 */
-		Assert(tupdesc1->attrs[i1]->attlen ==
-			   tupdesc2->attrs[i2]->attlen);
+		Assert(att1->attlen == att2->attlen);
 
 		/*
 		 * We consider two NULLs equal; NULL > not-NULL.
@@ -1426,7 +1442,7 @@ record_image_cmp(FunctionCallInfo fcinfo)
 			}
 
 			/* Compare the pair of elements */
-			if (tupdesc1->attrs[i1]->attlen == -1)
+			if (att1->attlen == -1)
 			{
 				Size		len1,
 							len2;
@@ -1449,9 +1465,9 @@ record_image_cmp(FunctionCallInfo fcinfo)
 				if ((Pointer) arg2val != (Pointer) values2[i2])
 					pfree(arg2val);
 			}
-			else if (tupdesc1->attrs[i1]->attbyval)
+			else if (att1->attbyval)
 			{
-				switch (tupdesc1->attrs[i1]->attlen)
+				switch (att1->attlen)
 				{
 					case 1:
 						if (GET_1_BYTE(values1[i1]) !=
@@ -1495,7 +1511,7 @@ record_image_cmp(FunctionCallInfo fcinfo)
 			{
 				cmpresult = memcmp(DatumGetPointer(values1[i1]),
 								   DatumGetPointer(values2[i2]),
-								   tupdesc1->attrs[i1]->attlen);
+								   att1->attlen);
 			}
 
 			if (cmpresult < 0)
@@ -1647,15 +1663,18 @@ record_image_eq(PG_FUNCTION_ARGS)
 	i1 = i2 = j = 0;
 	while (i1 < ncolumns1 || i2 < ncolumns2)
 	{
+		Form_pg_attribute att1;
+		Form_pg_attribute att2;
+
 		/*
 		 * Skip dropped columns
 		 */
-		if (i1 < ncolumns1 && tupdesc1->attrs[i1]->attisdropped)
+		if (i1 < ncolumns1 && TupleDescAttr(tupdesc1, i1)->attisdropped)
 		{
 			i1++;
 			continue;
 		}
-		if (i2 < ncolumns2 && tupdesc2->attrs[i2]->attisdropped)
+		if (i2 < ncolumns2 && TupleDescAttr(tupdesc2, i2)->attisdropped)
 		{
 			i2++;
 			continue;
@@ -1663,16 +1682,18 @@ record_image_eq(PG_FUNCTION_ARGS)
 		if (i1 >= ncolumns1 || i2 >= ncolumns2)
 			break;				/* we'll deal with mismatch below loop */
 
+		att1 = TupleDescAttr(tupdesc1, i1);
+		att2 = TupleDescAttr(tupdesc2, i2);
+
 		/*
 		 * Have two matching columns, they must be same type
 		 */
-		if (tupdesc1->attrs[i1]->atttypid !=
-			tupdesc2->attrs[i2]->atttypid)
+		if (att1->atttypid != att2->atttypid)
 			ereport(ERROR,
 					(errcode(ERRCODE_DATATYPE_MISMATCH),
 					 errmsg("cannot compare dissimilar column types %s and %s at record column %d",
-							format_type_be(tupdesc1->attrs[i1]->atttypid),
-							format_type_be(tupdesc2->attrs[i2]->atttypid),
+							format_type_be(att1->atttypid),
+							format_type_be(att2->atttypid),
 							j + 1)));
 
 		/*
@@ -1687,7 +1708,7 @@ record_image_eq(PG_FUNCTION_ARGS)
 			}
 
 			/* Compare the pair of elements */
-			if (tupdesc1->attrs[i1]->attlen == -1)
+			if (att1->attlen == -1)
 			{
 				Size		len1,
 							len2;
@@ -1716,9 +1737,9 @@ record_image_eq(PG_FUNCTION_ARGS)
 						pfree(arg2val);
 				}
 			}
-			else if (tupdesc1->attrs[i1]->attbyval)
+			else if (att1->attbyval)
 			{
-				switch (tupdesc1->attrs[i1]->attlen)
+				switch (att1->attlen)
 				{
 					case 1:
 						result = (GET_1_BYTE(values1[i1]) ==
@@ -1746,7 +1767,7 @@ record_image_eq(PG_FUNCTION_ARGS)
 			{
 				result = (memcmp(DatumGetPointer(values1[i1]),
 								 DatumGetPointer(values2[i2]),
-								 tupdesc1->attrs[i1]->attlen) == 0);
+								 att1->attlen) == 0);
 			}
 			if (!result)
 				break;
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 7469ec773c6..43646d2c4f8 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -3698,10 +3698,12 @@ set_relation_column_names(deparse_namespace *dpns, RangeTblEntry *rte,
 
 		for (i = 0; i < ncolumns; i++)
 		{
-			if (tupdesc->attrs[i]->attisdropped)
+			Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
+
+			if (attr->attisdropped)
 				real_colnames[i] = NULL;
 			else
-				real_colnames[i] = pstrdup(NameStr(tupdesc->attrs[i]->attname));
+				real_colnames[i] = pstrdup(NameStr(attr->attname));
 		}
 		relation_close(rel, AccessShareLock);
 	}
@@ -5391,7 +5393,7 @@ get_target_list(List *targetList, deparse_context *context,
 		 * Otherwise, just use what we can find in the TLE.
 		 */
 		if (resultDesc && colno <= resultDesc->natts)
-			colname = NameStr(resultDesc->attrs[colno - 1]->attname);
+			colname = NameStr(TupleDescAttr(resultDesc, colno - 1)->attname);
 		else
 			colname = tle->resname;
 
@@ -6741,7 +6743,7 @@ get_name_for_var_field(Var *var, int fieldno,
 		Assert(tupleDesc);
 		/* Got the tupdesc, so we can extract the field name */
 		Assert(fieldno >= 1 && fieldno <= tupleDesc->natts);
-		return NameStr(tupleDesc->attrs[fieldno - 1]->attname);
+		return NameStr(TupleDescAttr(tupleDesc, fieldno - 1)->attname);
 	}
 
 	/* Find appropriate nesting depth */
@@ -7051,7 +7053,7 @@ get_name_for_var_field(Var *var, int fieldno,
 	Assert(tupleDesc);
 	/* Got the tupdesc, so we can extract the field name */
 	Assert(fieldno >= 1 && fieldno <= tupleDesc->natts);
-	return NameStr(tupleDesc->attrs[fieldno - 1]->attname);
+	return NameStr(TupleDescAttr(tupleDesc, fieldno - 1)->attname);
 }
 
 /*
@@ -8180,7 +8182,7 @@ get_rule_expr(Node *node, deparse_context *context,
 					Node	   *e = (Node *) lfirst(arg);
 
 					if (tupdesc == NULL ||
-						!tupdesc->attrs[i]->attisdropped)
+						!TupleDescAttr(tupdesc, i)->attisdropped)
 					{
 						appendStringInfoString(buf, sep);
 						/* Whole-row Vars need special treatment here */
@@ -8193,7 +8195,7 @@ get_rule_expr(Node *node, deparse_context *context,
 				{
 					while (i < tupdesc->natts)
 					{
-						if (!tupdesc->attrs[i]->attisdropped)
+						if (!TupleDescAttr(tupdesc, i)->attisdropped)
 						{
 							appendStringInfoString(buf, sep);
 							appendStringInfoString(buf, "NULL");
diff --git a/src/backend/utils/adt/tid.c b/src/backend/utils/adt/tid.c
index 8453b65e78a..083f7d60a7b 100644
--- a/src/backend/utils/adt/tid.c
+++ b/src/backend/utils/adt/tid.c
@@ -273,9 +273,11 @@ currtid_for_view(Relation viewrel, ItemPointer tid)
 
 	for (i = 0; i < natts; i++)
 	{
-		if (strcmp(NameStr(att->attrs[i]->attname), "ctid") == 0)
+		Form_pg_attribute attr = TupleDescAttr(att, i);
+
+		if (strcmp(NameStr(attr->attname), "ctid") == 0)
 		{
-			if (att->attrs[i]->atttypid != TIDOID)
+			if (attr->atttypid != TIDOID)
 				elog(ERROR, "ctid isn't of type TID");
 			tididx = i;
 			break;
diff --git a/src/backend/utils/adt/xml.c b/src/backend/utils/adt/xml.c
index c47624eff68..24229c2dff7 100644
--- a/src/backend/utils/adt/xml.c
+++ b/src/backend/utils/adt/xml.c
@@ -3099,13 +3099,15 @@ map_sql_table_to_xmlschema(TupleDesc tupdesc, Oid relid, bool nulls,
 
 	for (i = 0; i < tupdesc->natts; i++)
 	{
-		if (tupdesc->attrs[i]->attisdropped)
+		Form_pg_attribute att = TupleDescAttr(tupdesc, i);
+
+		if (att->attisdropped)
 			continue;
 		appendStringInfo(&result,
 						 "    <xsd:element name=\"%s\" type=\"%s\"%s></xsd:element>\n",
-						 map_sql_identifier_to_xml_name(NameStr(tupdesc->attrs[i]->attname),
+						 map_sql_identifier_to_xml_name(NameStr(att->attname),
 														true, false),
-						 map_sql_type_to_xml_name(tupdesc->attrs[i]->atttypid, -1),
+						 map_sql_type_to_xml_name(att->atttypid, -1),
 						 nulls ? " nillable=\"true\"" : " minOccurs=\"0\"");
 	}
 
@@ -3392,10 +3394,11 @@ map_sql_typecoll_to_xmlschema_types(List *tupdesc_list)
 
 		for (i = 0; i < tupdesc->natts; i++)
 		{
-			if (tupdesc->attrs[i]->attisdropped)
+			Form_pg_attribute att = TupleDescAttr(tupdesc, i);
+
+			if (att->attisdropped)
 				continue;
-			uniquetypes = list_append_unique_oid(uniquetypes,
-												 tupdesc->attrs[i]->atttypid);
+			uniquetypes = list_append_unique_oid(uniquetypes, att->atttypid);
 		}
 	}