Improve castNode notation by introducing list-extraction-specific variants.

This extends the castNode() notation introduced by commit 5bcab1114 to
provide, in one step, extraction of a list cell's pointer and coercion to
a concrete node type.  For example, "lfirst_node(Foo, lc)" is the same
as "castNode(Foo, lfirst(lc))".  Almost half of the uses of castNode
that have appeared so far include a list extraction call, so this is
pretty widely useful, and it saves a few more keystrokes compared to the
old way.

As with the previous patch, back-patch the addition of these macros to
pg_list.h, so that the notation will be available when back-patching.

Patch by me, after an idea of Andrew Gierth's.

Discussion: https://postgr.es/m/14197.1491841216@sss.pgh.pa.us

contrib/pg_stat_statements/pg_stat_statements.c

@@ -2393,7 +2393,7 @@ JumbleRangeTable(pgssJumbleState *jstate, List *rtable)
 
 	foreach(lc, rtable)
 	{
-		RangeTblEntry *rte = castNode(RangeTblEntry, lfirst(lc));
+		RangeTblEntry *rte = lfirst_node(RangeTblEntry, lc);
 
 		APP_JUMB(rte->rtekind);
 		switch (rte->rtekind)
@@ -2656,7 +2656,7 @@ JumbleExpr(pgssJumbleState *jstate, Node *node)
 				JumbleExpr(jstate, (Node *) caseexpr->arg);
 				foreach(temp, caseexpr->args)
 				{
-					CaseWhen   *when = castNode(CaseWhen, lfirst(temp));
+					CaseWhen   *when = lfirst_node(CaseWhen, temp);
 
 					JumbleExpr(jstate, (Node *) when->expr);
 					JumbleExpr(jstate, (Node *) when->result);

contrib/postgres_fdw/deparse.c

@@ -1350,7 +1350,7 @@ deparseExplicitTargetList(List *tlist, List **retrieved_attrs,
 
 	foreach(lc, tlist)
 	{
-		TargetEntry *tle = castNode(TargetEntry, lfirst(lc));
+		TargetEntry *tle = lfirst_node(TargetEntry, lc);
 
 		if (i > 0)
 			appendStringInfoString(buf, ", ");

contrib/postgres_fdw/postgres_fdw.c

@@ -1169,7 +1169,7 @@ postgresGetForeignPlan(PlannerInfo *root,
 	 */
 	foreach(lc, scan_clauses)
 	{
-		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(lc));
+		RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc);
 
 		/* Ignore any pseudoconstants, they're dealt with elsewhere */
 		if (rinfo->pseudoconstant)
@@ -5022,8 +5022,8 @@ conversion_error_callback(void *arg)
 		EState	   *estate = fsstate->ss.ps.state;
 		TargetEntry *tle;
 
-		tle = castNode(TargetEntry, list_nth(fsplan->fdw_scan_tlist,
+		tle = list_nth_node(TargetEntry, fsplan->fdw_scan_tlist,
-											 errpos->cur_attno - 1));
+							errpos->cur_attno - 1);
 
 		/*
 		 * Target list can have Vars and expressions.  For Vars, we can get

src/backend/catalog/objectaddress.c

@@ -854,7 +854,7 @@ get_object_address(ObjectType objtype, Node *object,
 
 					objlist = castNode(List, object);
 					domaddr = get_object_address_type(OBJECT_DOMAIN,
-													  castNode(TypeName, linitial(objlist)),
+													  linitial_node(TypeName, objlist),
 													  missing_ok);
 					constrname = strVal(lsecond(objlist));
 
@@ -932,8 +932,8 @@ get_object_address(ObjectType objtype, Node *object,
 				break;
 			case OBJECT_CAST:
 				{
-					TypeName   *sourcetype = castNode(TypeName, linitial(castNode(List, object)));
+					TypeName   *sourcetype = linitial_node(TypeName, castNode(List, object));
-					TypeName   *targettype = castNode(TypeName, lsecond(castNode(List, object)));
+					TypeName   *targettype = lsecond_node(TypeName, castNode(List, object));
 					Oid			sourcetypeid;
 					Oid			targettypeid;
 
@@ -947,7 +947,7 @@ get_object_address(ObjectType objtype, Node *object,
 				break;
 			case OBJECT_TRANSFORM:
 				{
-					TypeName   *typename = castNode(TypeName, linitial(castNode(List, object)));
+					TypeName   *typename = linitial_node(TypeName, castNode(List, object));
 					char	   *langname = strVal(lsecond(castNode(List, object)));
 					Oid			type_id = LookupTypeNameOid(NULL, typename, missing_ok);
 					Oid			lang_id = get_language_oid(langname, missing_ok);
@@ -1597,7 +1597,7 @@ get_object_address_opf_member(ObjectType objtype,
 	{
 		ObjectAddress typaddr;
 
-		typenames[i] = castNode(TypeName, lfirst(cell));
+		typenames[i] = lfirst_node(TypeName, cell);
 		typaddr = get_object_address_type(OBJECT_TYPE, typenames[i], missing_ok);
 		typeoids[i] = typaddr.objectId;
 		if (++i >= 2)
@@ -2319,8 +2319,8 @@ check_object_ownership(Oid roleid, ObjectType objtype, ObjectAddress address,
 		case OBJECT_CAST:
 			{
 				/* We can only check permissions on the source/target types */
-				TypeName   *sourcetype = castNode(TypeName, linitial(castNode(List, object)));
+				TypeName   *sourcetype = linitial_node(TypeName, castNode(List, object));
-				TypeName   *targettype = castNode(TypeName, lsecond(castNode(List, object)));
+				TypeName   *targettype = lsecond_node(TypeName, castNode(List, object));
 				Oid			sourcetypeid = typenameTypeId(NULL, sourcetype);
 				Oid			targettypeid = typenameTypeId(NULL, targettype);
 
@@ -2345,7 +2345,7 @@ check_object_ownership(Oid roleid, ObjectType objtype, ObjectAddress address,
 			break;
 		case OBJECT_TRANSFORM:
 			{
-				TypeName   *typename = castNode(TypeName, linitial(castNode(List, object)));
+				TypeName   *typename = linitial_node(TypeName, castNode(List, object));
 				Oid			typeid = typenameTypeId(NULL, typename);
 
 				if (!pg_type_ownercheck(typeid, roleid))

src/backend/catalog/pg_proc.c

@@ -928,7 +928,7 @@ fmgr_sql_validator(PG_FUNCTION_ARGS)
 			querytree_list = NIL;
 			foreach(lc, raw_parsetree_list)
 			{
-				RawStmt    *parsetree = castNode(RawStmt, lfirst(lc));
+				RawStmt    *parsetree = lfirst_node(RawStmt, lc);
 				List	   *querytree_sublist;
 
 				querytree_sublist = pg_analyze_and_rewrite_params(parsetree,

src/backend/commands/aggregatecmds.c

@@ -109,13 +109,13 @@ DefineAggregate(ParseState *pstate, List *name, List *args, bool oldstyle, List
 			aggKind = AGGKIND_ORDERED_SET;
 		else
 			numDirectArgs = 0;
-		args = castNode(List, linitial(args));
+		args = linitial_node(List, args);
 	}
 
 	/* Examine aggregate's definition clauses */
 	foreach(pl, parameters)
 	{
-		DefElem    *defel = castNode(DefElem, lfirst(pl));
+		DefElem    *defel = lfirst_node(DefElem, pl);
 
 		/*
 		 * sfunc1, stype1, and initcond1 are accepted as obsolete spellings

src/backend/commands/async.c

@@ -1636,7 +1636,7 @@ AtSubCommit_Notify(void)
 	List	   *parentPendingActions;
 	List	   *parentPendingNotifies;
 
-	parentPendingActions = castNode(List, linitial(upperPendingActions));
+	parentPendingActions = linitial_node(List, upperPendingActions);
 	upperPendingActions = list_delete_first(upperPendingActions);
 
 	Assert(list_length(upperPendingActions) ==
@@ -1647,7 +1647,7 @@ AtSubCommit_Notify(void)
 	 */
 	pendingActions = list_concat(parentPendingActions, pendingActions);
 
-	parentPendingNotifies = castNode(List, linitial(upperPendingNotifies));
+	parentPendingNotifies = linitial_node(List, upperPendingNotifies);
 	upperPendingNotifies = list_delete_first(upperPendingNotifies);
 
 	Assert(list_length(upperPendingNotifies) ==
@@ -1679,13 +1679,13 @@ AtSubAbort_Notify(void)
 	 */
 	while (list_length(upperPendingActions) > my_level - 2)
 	{
-		pendingActions = castNode(List, linitial(upperPendingActions));
+		pendingActions = linitial_node(List, upperPendingActions);
 		upperPendingActions = list_delete_first(upperPendingActions);
 	}
 
 	while (list_length(upperPendingNotifies) > my_level - 2)
 	{
-		pendingNotifies = castNode(List, linitial(upperPendingNotifies));
+		pendingNotifies = linitial_node(List, upperPendingNotifies);
 		upperPendingNotifies = list_delete_first(upperPendingNotifies);
 	}
 }

src/backend/commands/collationcmds.c

@@ -71,7 +71,7 @@ DefineCollation(ParseState *pstate, List *names, List *parameters, bool if_not_e
 
 	foreach(pl, parameters)
 	{
-		DefElem    *defel = castNode(DefElem, lfirst(pl));
+		DefElem    *defel = lfirst_node(DefElem, pl);
 		DefElem   **defelp;
 
 		if (pg_strcasecmp(defel->defname, "from") == 0)

src/backend/commands/copy.c

@@ -1034,7 +1034,7 @@ ProcessCopyOptions(ParseState *pstate,
 	/* Extract options from the statement node tree */
 	foreach(option, options)
 	{
-		DefElem    *defel = castNode(DefElem, lfirst(option));
+		DefElem    *defel = lfirst_node(DefElem, option);
 
 		if (strcmp(defel->defname, "format") == 0)
 		{
@@ -1488,7 +1488,7 @@ BeginCopy(ParseState *pstate,
 			/* examine queries to determine which error message to issue */
 			foreach(lc, rewritten)
 			{
-				Query	   *q = castNode(Query, lfirst(lc));
+				Query	   *q = lfirst_node(Query, lc);
 
 				if (q->querySource == QSRC_QUAL_INSTEAD_RULE)
 					ereport(ERROR,
@@ -1505,7 +1505,7 @@ BeginCopy(ParseState *pstate,
 					 errmsg("multi-statement DO INSTEAD rules are not supported for COPY")));
 		}
 
-		query = castNode(Query, linitial(rewritten));
+		query = linitial_node(Query, rewritten);
 
 		/* The grammar allows SELECT INTO, but we don't support that */
 		if (query->utilityStmt != NULL &&

src/backend/commands/createas.c

@@ -323,7 +323,7 @@ ExecCreateTableAs(CreateTableAsStmt *stmt, const char *queryString,
 			elog(ERROR, "unexpected rewrite result for %s",
 				 is_matview ? "CREATE MATERIALIZED VIEW" :
 				 "CREATE TABLE AS SELECT");
-		query = castNode(Query, linitial(rewritten));
+		query = linitial_node(Query, rewritten);
 		Assert(query->commandType == CMD_SELECT);
 
 		/* plan the query --- note we disallow parallelism */

src/backend/commands/dropcmds.c

@@ -214,7 +214,7 @@ type_in_list_does_not_exist_skipping(List *typenames, const char **msg,
 
 	foreach(l, typenames)
 	{
-		TypeName   *typeName = castNode(TypeName, lfirst(l));
+		TypeName   *typeName = lfirst_node(TypeName, l);
 
 		if (typeName != NULL)
 		{
@@ -371,8 +371,8 @@ does_not_exist_skipping(ObjectType objtype, Node *object)
 				{
 					/* XXX quote or no quote? */
 					msg = gettext_noop("cast from type %s to type %s does not exist, skipping");
-					name = TypeNameToString(castNode(TypeName, linitial(castNode(List, object))));
+					name = TypeNameToString(linitial_node(TypeName, castNode(List, object)));
-					args = TypeNameToString(castNode(TypeName, lsecond(castNode(List, object))));
+					args = TypeNameToString(lsecond_node(TypeName, castNode(List, object)));
 				}
 			}
 			break;
@@ -380,7 +380,7 @@ does_not_exist_skipping(ObjectType objtype, Node *object)
 			if (!type_in_list_does_not_exist_skipping(list_make1(linitial(castNode(List, object))), &msg, &name))
 			{
 				msg = gettext_noop("transform for type %s language \"%s\" does not exist, skipping");
-				name = TypeNameToString(castNode(TypeName, linitial(castNode(List, object))));
+				name = TypeNameToString(linitial_node(TypeName, castNode(List, object)));
 				args = strVal(lsecond(castNode(List, object)));
 			}
 			break;

src/backend/commands/explain.c

@@ -253,7 +253,7 @@ ExplainQuery(ParseState *pstate, ExplainStmt *stmt, const char *queryString,
 		/* Explain every plan */
 		foreach(l, rewritten)
 		{
-			ExplainOneQuery(castNode(Query, lfirst(l)),
+			ExplainOneQuery(lfirst_node(Query, l),
 							CURSOR_OPT_PARALLEL_OK, NULL, es,
 							queryString, params, queryEnv);
 
@@ -408,7 +408,7 @@ ExplainOneUtility(Node *utilityStmt, IntoClause *into, ExplainState *es,
 
 		rewritten = QueryRewrite(castNode(Query, copyObject(ctas->query)));
 		Assert(list_length(rewritten) == 1);
-		ExplainOneQuery(castNode(Query, linitial(rewritten)),
+		ExplainOneQuery(linitial_node(Query, rewritten),
 						0, ctas->into, es,
 						queryString, params, queryEnv);
 	}
@@ -427,7 +427,7 @@ ExplainOneUtility(Node *utilityStmt, IntoClause *into, ExplainState *es,
 
 		rewritten = QueryRewrite(castNode(Query, copyObject(dcs->query)));
 		Assert(list_length(rewritten) == 1);
-		ExplainOneQuery(castNode(Query, linitial(rewritten)),
+		ExplainOneQuery(linitial_node(Query, rewritten),
 						dcs->options, NULL, es,
 						queryString, params, queryEnv);
 	}

src/backend/commands/extension.c

@@ -714,7 +714,7 @@ execute_sql_string(const char *sql, const char *filename)
 	 */
 	foreach(lc1, raw_parsetree_list)
 	{
-		RawStmt    *parsetree = castNode(RawStmt, lfirst(lc1));
+		RawStmt    *parsetree = lfirst_node(RawStmt, lc1);
 		List	   *stmt_list;
 		ListCell   *lc2;
 
@@ -727,7 +727,7 @@ execute_sql_string(const char *sql, const char *filename)
 
 		foreach(lc2, stmt_list)
 		{
-			PlannedStmt *stmt = castNode(PlannedStmt, lfirst(lc2));
+			PlannedStmt *stmt = lfirst_node(PlannedStmt, lc2);
 
 			CommandCounterIncrement();
 

src/backend/commands/foreigncmds.c

@@ -1589,7 +1589,7 @@ ImportForeignSchema(ImportForeignSchemaStmt *stmt)
 		 */
 		foreach(lc2, raw_parsetree_list)
 		{
-			RawStmt    *rs = castNode(RawStmt, lfirst(lc2));
+			RawStmt    *rs = lfirst_node(RawStmt, lc2);
 			CreateForeignTableStmt *cstmt = (CreateForeignTableStmt *) rs->stmt;
 			PlannedStmt *pstmt;
 

src/backend/commands/functioncmds.c

@@ -578,7 +578,7 @@ update_proconfig_value(ArrayType *a, List *set_items)
 
 	foreach(l, set_items)
 	{
-		VariableSetStmt *sstmt = castNode(VariableSetStmt, lfirst(l));
+		VariableSetStmt *sstmt = lfirst_node(VariableSetStmt, l);
 
 		if (sstmt->kind == VAR_RESET_ALL)
 			a = NULL;
@@ -972,7 +972,8 @@ CreateFunction(ParseState *pstate, CreateFunctionStmt *stmt)
 
 		foreach(lc, castNode(List, transformDefElem))
 		{
-			Oid			typeid = typenameTypeId(NULL, lfirst(lc));
+			Oid			typeid = typenameTypeId(NULL,
+												lfirst_node(TypeName, lc));
 			Oid			elt = get_base_element_type(typeid);
 
 			typeid = elt ? elt : typeid;

src/backend/commands/matview.c

@@ -264,7 +264,7 @@ ExecRefreshMatView(RefreshMatViewStmt *stmt, const char *queryString,
 	 * The stored query was rewritten at the time of the MV definition, but
 	 * has not been scribbled on by the planner.
 	 */
-	dataQuery = castNode(Query, linitial(actions));
+	dataQuery = linitial_node(Query, actions);
 
 	/*
 	 * Check for active uses of the relation in the current transaction, such

src/backend/commands/opclasscmds.c

@@ -460,7 +460,7 @@ DefineOpClass(CreateOpClassStmt *stmt)
 	 */
 	foreach(l, stmt->items)
 	{
-		CreateOpClassItem *item = castNode(CreateOpClassItem, lfirst(l));
+		CreateOpClassItem *item = lfirst_node(CreateOpClassItem, l);
 		Oid			operOid;
 		Oid			funcOid;
 		Oid			sortfamilyOid;
@@ -834,7 +834,7 @@ AlterOpFamilyAdd(AlterOpFamilyStmt *stmt, Oid amoid, Oid opfamilyoid,
 	 */
 	foreach(l, items)
 	{
-		CreateOpClassItem *item = castNode(CreateOpClassItem, lfirst(l));
+		CreateOpClassItem *item = lfirst_node(CreateOpClassItem, l);
 		Oid			operOid;
 		Oid			funcOid;
 		Oid			sortfamilyOid;
@@ -959,7 +959,7 @@ AlterOpFamilyDrop(AlterOpFamilyStmt *stmt, Oid amoid, Oid opfamilyoid,
 	 */
 	foreach(l, items)
 	{
-		CreateOpClassItem *item = castNode(CreateOpClassItem, lfirst(l));
+		CreateOpClassItem *item = lfirst_node(CreateOpClassItem, l);
 		Oid			lefttype,
 					righttype;
 		OpFamilyMember *member;

src/backend/commands/portalcmds.c

@@ -83,7 +83,7 @@ PerformCursorOpen(DeclareCursorStmt *cstmt, ParamListInfo params,
 	if (list_length(rewritten) != 1)
 		elog(ERROR, "non-SELECT statement in DECLARE CURSOR");
 
-	query = castNode(Query, linitial(rewritten));
+	query = linitial_node(Query, rewritten);
 
 	if (query->commandType != CMD_SELECT)
 		elog(ERROR, "non-SELECT statement in DECLARE CURSOR");

src/backend/commands/prepare.c

@@ -267,7 +267,7 @@ ExecuteQuery(ExecuteStmt *stmt, IntoClause *intoClause,
 			ereport(ERROR,
 					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
 					 errmsg("prepared statement is not a SELECT")));
-		pstmt = castNode(PlannedStmt, linitial(plan_list));
+		pstmt = linitial_node(PlannedStmt, plan_list);
 		if (pstmt->commandType != CMD_SELECT)
 			ereport(ERROR,
 					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
@@ -679,7 +679,7 @@ ExplainExecuteQuery(ExecuteStmt *execstmt, IntoClause *into, ExplainState *es,
 	/* Explain each query */
 	foreach(p, plan_list)
 	{
-		PlannedStmt *pstmt = castNode(PlannedStmt, lfirst(p));
+		PlannedStmt *pstmt = lfirst_node(PlannedStmt, p);
 
 		if (pstmt->commandType != CMD_UTILITY)
 			ExplainOnePlan(pstmt, into, es, query_string, paramLI, queryEnv,

src/backend/commands/tablecmds.c

@@ -5942,7 +5942,7 @@ ATExecSetIdentity(Relation rel, const char *colName, Node *def, LOCKMODE lockmod
 
 	foreach(option, castNode(List, def))
 	{
-		DefElem	   *defel = castNode(DefElem, lfirst(option));
+		DefElem	   *defel = lfirst_node(DefElem, option);
 
 		if (strcmp(defel->defname, "generated") == 0)
 		{
@@ -9547,7 +9547,7 @@ ATPostAlterTypeParse(Oid oldId, Oid oldRelId, Oid refRelId, char *cmd,
 	querytree_list = NIL;
 	foreach(list_item, raw_parsetree_list)
 	{
-		RawStmt    *rs = castNode(RawStmt, lfirst(list_item));
+		RawStmt    *rs = lfirst_node(RawStmt, list_item);
 		Node	   *stmt = rs->stmt;
 
 		if (IsA(stmt, IndexStmt))

src/backend/commands/trigger.c

@@ -340,7 +340,7 @@ CreateTrigger(CreateTrigStmt *stmt, const char *queryString,
 
 		foreach(lc, varList)
 		{
-			TriggerTransition   *tt = castNode(TriggerTransition, lfirst(lc));
+			TriggerTransition   *tt = lfirst_node(TriggerTransition, lc);
 
 			if (!(tt->isTable))
 				ereport(ERROR,

src/backend/commands/user.c

@@ -1388,7 +1388,7 @@ roleSpecsToIds(List *memberNames)
 
 	foreach(l, memberNames)
 	{
-		RoleSpec   *rolespec = castNode(RoleSpec, lfirst(l));
+		RoleSpec   *rolespec = lfirst_node(RoleSpec, l);
 		Oid			roleid;
 
 		roleid = get_rolespec_oid(rolespec, false);

src/backend/commands/view.c

@@ -516,7 +516,7 @@ DefineView(ViewStmt *stmt, const char *queryString,
 
 		foreach(targetList, viewParse->targetList)
 		{
-			TargetEntry *te = castNode(TargetEntry, lfirst(targetList));
+			TargetEntry *te = lfirst_node(TargetEntry, targetList);
 
 			/* junk columns don't get aliases */
 			if (te->resjunk)

src/backend/executor/execExpr.c

@@ -322,7 +322,7 @@ ExecBuildProjectionInfo(List *targetList,
 	/* Now compile each tlist column */
 	foreach(lc, targetList)
 	{
-		TargetEntry *tle = castNode(TargetEntry, lfirst(lc));
+		TargetEntry *tle = lfirst_node(TargetEntry, lc);
 		Var		   *variable = NULL;
 		AttrNumber	attnum = 0;
 		bool		isSafeVar = false;

src/backend/executor/execTuples.c

@@ -160,7 +160,7 @@ ExecResetTupleTable(List *tupleTable,	/* tuple table */
 
 	foreach(lc, tupleTable)
 	{
-		TupleTableSlot *slot = castNode(TupleTableSlot, lfirst(lc));
+		TupleTableSlot *slot = lfirst_node(TupleTableSlot, lc);
 
 		/* Always release resources and reset the slot to empty */
 		ExecClearTuple(slot);

src/backend/executor/execUtils.c

@@ -978,7 +978,7 @@ ExecCleanTargetListLength(List *targetlist)
 
 	foreach(tl, targetlist)
 	{
-		TargetEntry *curTle = castNode(TargetEntry, lfirst(tl));
+		TargetEntry *curTle = lfirst_node(TargetEntry, tl);
 
 		if (!curTle->resjunk)
 			len++;

src/backend/executor/functions.c

@@ -479,14 +479,14 @@ init_execution_state(List *queryTree_list,
 
 	foreach(lc1, queryTree_list)
 	{
-		List	   *qtlist = castNode(List, lfirst(lc1));
+		List	   *qtlist = lfirst_node(List, lc1);
 		execution_state *firstes = NULL;
 		execution_state *preves = NULL;
 		ListCell   *lc2;
 
 		foreach(lc2, qtlist)
 		{
-			Query	   *queryTree = castNode(Query, lfirst(lc2));
+			Query	   *queryTree = lfirst_node(Query, lc2);
 			PlannedStmt *stmt;
 			execution_state *newes;
 
@@ -707,7 +707,7 @@ init_sql_fcache(FmgrInfo *finfo, Oid collation, bool lazyEvalOK)
 	flat_query_list = NIL;
 	foreach(lc, raw_parsetree_list)
 	{
-		RawStmt    *parsetree = castNode(RawStmt, lfirst(lc));
+		RawStmt    *parsetree = lfirst_node(RawStmt, lc);
 		List	   *queryTree_sublist;
 
 		queryTree_sublist = pg_analyze_and_rewrite_params(parsetree,
@@ -1555,7 +1555,7 @@ check_sql_fn_retval(Oid func_id, Oid rettype, List *queryTreeList,
 	parse = NULL;
 	foreach(lc, queryTreeList)
 	{
-		Query	   *q = castNode(Query, lfirst(lc));
+		Query	   *q = lfirst_node(Query, lc);
 
 		if (q->canSetTag)
 			parse = q;

src/backend/executor/nodeAgg.c

@@ -2866,7 +2866,7 @@ ExecInitAgg(Agg *node, EState *estate, int eflags)
 
 		if (phaseidx > 0)
 		{
-			aggnode = castNode(Agg, list_nth(node->chain, phaseidx - 1));
+			aggnode = list_nth_node(Agg, node->chain, phaseidx - 1);
 			sortnode = castNode(Sort, aggnode->plan.lefttree);
 		}
 		else
@@ -3360,7 +3360,7 @@ ExecInitAgg(Agg *node, EState *estate, int eflags)
 		 */
 		foreach(arg, pertrans->aggref->args)
 		{
-			TargetEntry *source_tle = castNode(TargetEntry, lfirst(arg));
+			TargetEntry *source_tle = lfirst_node(TargetEntry, arg);
 			TargetEntry *tle;
 
 			tle = flatCopyTargetEntry(source_tle);

src/backend/executor/nodeHashjoin.c

@@ -517,7 +517,7 @@ ExecInitHashJoin(HashJoin *node, EState *estate, int eflags)
 	hoperators = NIL;
 	foreach(l, node->hashclauses)
 	{
-		OpExpr	   *hclause = castNode(OpExpr, lfirst(l));
+		OpExpr	   *hclause = lfirst_node(OpExpr, l);
 
 		lclauses = lappend(lclauses, ExecInitExpr(linitial(hclause->args),
 												  (PlanState *) hjstate));

src/backend/executor/nodeLockRows.c

@@ -401,7 +401,7 @@ ExecInitLockRows(LockRows *node, EState *estate, int eflags)
 	epq_arowmarks = NIL;
 	foreach(lc, node->rowMarks)
 	{
-		PlanRowMark *rc = castNode(PlanRowMark, lfirst(lc));
+		PlanRowMark *rc = lfirst_node(PlanRowMark, lc);
 		ExecRowMark *erm;
 		ExecAuxRowMark *aerm;
 

src/backend/executor/nodeModifyTable.c

@@ -1968,7 +1968,7 @@ ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags)
 	 */
 	foreach(l, node->rowMarks)
 	{
-		PlanRowMark *rc = castNode(PlanRowMark, lfirst(l));
+		PlanRowMark *rc = lfirst_node(PlanRowMark, l);
 		ExecRowMark *erm;
 
 		/* ignore "parent" rowmarks; they are irrelevant at runtime */

src/backend/executor/nodeSubplan.c

@@ -817,7 +817,7 @@ ExecInitSubPlan(SubPlan *subplan, PlanState *parent)
 		i = 1;
 		foreach(l, oplist)
 		{
-			OpExpr	   *opexpr = castNode(OpExpr, lfirst(l));
+			OpExpr	   *opexpr = lfirst_node(OpExpr, l);
 			Expr	   *expr;
 			TargetEntry *tle;
 			Oid			rhs_eq_oper;
@@ -1148,7 +1148,7 @@ ExecInitAlternativeSubPlan(AlternativeSubPlan *asplan, PlanState *parent)
 	 */
 	foreach(lc, asplan->subplans)
 	{
-		SubPlan    *sp = castNode(SubPlan, lfirst(lc));
+		SubPlan    *sp = lfirst_node(SubPlan, lc);
 		SubPlanState *sps = ExecInitSubPlan(sp, parent);
 
 		asstate->subplans = lappend(asstate->subplans, sps);
@@ -1197,8 +1197,8 @@ ExecAlternativeSubPlan(AlternativeSubPlanState *node,
 					   bool *isNull)
 {
 	/* Just pass control to the active subplan */
-	SubPlanState *activesp = castNode(SubPlanState,
+	SubPlanState *activesp = list_nth_node(SubPlanState,
-									  list_nth(node->subplans, node->active));
+										   node->subplans, node->active);
 
 	return ExecSubPlan(activesp, econtext, isNull);
 }

src/backend/executor/spi.c

@@ -1233,9 +1233,9 @@ SPI_cursor_open_internal(const char *name, SPIPlanPtr plan,
 	if (!(portal->cursorOptions & (CURSOR_OPT_SCROLL | CURSOR_OPT_NO_SCROLL)))
 	{
 		if (list_length(stmt_list) == 1 &&
-			castNode(PlannedStmt, linitial(stmt_list))->commandType != CMD_UTILITY &&
+			linitial_node(PlannedStmt, stmt_list)->commandType != CMD_UTILITY &&
-			castNode(PlannedStmt, linitial(stmt_list))->rowMarks == NIL &&
+			linitial_node(PlannedStmt, stmt_list)->rowMarks == NIL &&
-			ExecSupportsBackwardScan(castNode(PlannedStmt, linitial(stmt_list))->planTree))
+			ExecSupportsBackwardScan(linitial_node(PlannedStmt, stmt_list)->planTree))
 			portal->cursorOptions |= CURSOR_OPT_SCROLL;
 		else
 			portal->cursorOptions |= CURSOR_OPT_NO_SCROLL;
@@ -1249,8 +1249,8 @@ SPI_cursor_open_internal(const char *name, SPIPlanPtr plan,
 	if (portal->cursorOptions & CURSOR_OPT_SCROLL)
 	{
 		if (list_length(stmt_list) == 1 &&
-			castNode(PlannedStmt, linitial(stmt_list))->commandType != CMD_UTILITY &&
+			linitial_node(PlannedStmt, stmt_list)->commandType != CMD_UTILITY &&
-			castNode(PlannedStmt, linitial(stmt_list))->rowMarks != NIL)
+			linitial_node(PlannedStmt, stmt_list)->rowMarks != NIL)
 			ereport(ERROR,
 					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 					 errmsg("DECLARE SCROLL CURSOR ... FOR UPDATE/SHARE is not supported"),
@@ -1274,7 +1274,7 @@ SPI_cursor_open_internal(const char *name, SPIPlanPtr plan,
 
 		foreach(lc, stmt_list)
 		{
-			PlannedStmt *pstmt = castNode(PlannedStmt, lfirst(lc));
+			PlannedStmt *pstmt = lfirst_node(PlannedStmt, lc);
 
 			if (!CommandIsReadOnly(pstmt))
 			{
@@ -1770,7 +1770,7 @@ _SPI_prepare_plan(const char *src, SPIPlanPtr plan)
 
 	foreach(list_item, raw_parsetree_list)
 	{
-		RawStmt    *parsetree = castNode(RawStmt, lfirst(list_item));
+		RawStmt    *parsetree = lfirst_node(RawStmt, list_item);
 		List	   *stmt_list;
 		CachedPlanSource *plansource;
 
@@ -1874,7 +1874,7 @@ _SPI_prepare_oneshot_plan(const char *src, SPIPlanPtr plan)
 
 	foreach(list_item, raw_parsetree_list)
 	{
-		RawStmt    *parsetree = castNode(RawStmt, lfirst(list_item));
+		RawStmt    *parsetree = lfirst_node(RawStmt, list_item);
 		CachedPlanSource *plansource;
 
 		plansource = CreateOneShotCachedPlan(parsetree,
@@ -2035,7 +2035,7 @@ _SPI_execute_plan(SPIPlanPtr plan, ParamListInfo paramLI,
 
 		foreach(lc2, stmt_list)
 		{
-			PlannedStmt *stmt = castNode(PlannedStmt, lfirst(lc2));
+			PlannedStmt *stmt = lfirst_node(PlannedStmt, lc2);
 			bool		canSetTag = stmt->canSetTag;
 			DestReceiver *dest;
 

src/backend/nodes/nodeFuncs.c

@@ -111,7 +111,7 @@ exprType(const Node *expr)
 
 					if (!qtree || !IsA(qtree, Query))
 						elog(ERROR, "cannot get type for untransformed sublink");
-					tent = castNode(TargetEntry, linitial(qtree->targetList));
+					tent = linitial_node(TargetEntry, qtree->targetList);
 					Assert(!tent->resjunk);
 					type = exprType((Node *) tent->expr);
 					if (sublink->subLinkType == ARRAY_SUBLINK)
@@ -324,7 +324,7 @@ exprTypmod(const Node *expr)
 
 					if (!qtree || !IsA(qtree, Query))
 						elog(ERROR, "cannot get type for untransformed sublink");
-					tent = castNode(TargetEntry, linitial(qtree->targetList));
+					tent = linitial_node(TargetEntry, qtree->targetList);
 					Assert(!tent->resjunk);
 					return exprTypmod((Node *) tent->expr);
 					/* note we don't need to care if it's an array */
@@ -382,7 +382,7 @@ exprTypmod(const Node *expr)
 					return -1;	/* no point in trying harder */
 				foreach(arg, cexpr->args)
 				{
-					CaseWhen   *w = castNode(CaseWhen, lfirst(arg));
+					CaseWhen   *w = lfirst_node(CaseWhen, arg);
 
 					if (exprType((Node *) w->result) != casetype)
 						return -1;
@@ -809,7 +809,7 @@ exprCollation(const Node *expr)
 
 					if (!qtree || !IsA(qtree, Query))
 						elog(ERROR, "cannot get collation for untransformed sublink");
-					tent = castNode(TargetEntry, linitial(qtree->targetList));
+					tent = linitial_node(TargetEntry, qtree->targetList);
 					Assert(!tent->resjunk);
 					coll = exprCollation((Node *) tent->expr);
 					/* collation doesn't change if it's converted to array */
@@ -1054,7 +1054,7 @@ exprSetCollation(Node *expr, Oid collation)
 
 					if (!qtree || !IsA(qtree, Query))
 						elog(ERROR, "cannot set collation for untransformed sublink");
-					tent = castNode(TargetEntry, linitial(qtree->targetList));
+					tent = linitial_node(TargetEntry, qtree->targetList);
 					Assert(!tent->resjunk);
 					Assert(collation == exprCollation((Node *) tent->expr));
 				}
@@ -2058,7 +2058,7 @@ expression_tree_walker(Node *node,
 				/* we assume walker doesn't care about CaseWhens, either */
 				foreach(temp, caseexpr->args)
 				{
-					CaseWhen   *when = castNode(CaseWhen, lfirst(temp));
+					CaseWhen   *when = lfirst_node(CaseWhen, temp);
 
 					if (walker(when->expr, context))
 						return true;
@@ -3308,7 +3308,7 @@ raw_expression_tree_walker(Node *node,
 				/* we assume walker doesn't care about CaseWhens, either */
 				foreach(temp, caseexpr->args)
 				{
-					CaseWhen   *when = castNode(CaseWhen, lfirst(temp));
+					CaseWhen   *when = lfirst_node(CaseWhen, temp);
 
 					if (walker(when->expr, context))
 						return true;
@@ -3807,7 +3807,7 @@ planstate_walk_subplans(List *plans,
 
 	foreach(lc, plans)
 	{
-		SubPlanState *sps = castNode(SubPlanState, lfirst(lc));
+		SubPlanState *sps = lfirst_node(SubPlanState, lc);
 
 		if (walker(sps->planstate, context))
 			return true;

src/backend/optimizer/path/costsize.c

@@ -757,7 +757,7 @@ extract_nonindex_conditions(List *qual_clauses, List *indexquals)
 
 	foreach(lc, qual_clauses)
 	{
-		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(lc));
+		RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc);
 
 		if (rinfo->pseudoconstant)
 			continue;			/* we may drop pseudoconstants here */
@@ -1990,7 +1990,7 @@ cost_windowagg(Path *path, PlannerInfo *root,
 	 */
 	foreach(lc, windowFuncs)
 	{
-		WindowFunc *wfunc = castNode(WindowFunc, lfirst(lc));
+		WindowFunc *wfunc = lfirst_node(WindowFunc, lc);
 		Cost		wfunccost;
 		QualCost	argcosts;
 
@@ -3066,7 +3066,7 @@ final_cost_hashjoin(PlannerInfo *root, HashPath *path,
 		innerbucketsize = 1.0;
 		foreach(hcl, hashclauses)
 		{
-			RestrictInfo *restrictinfo = castNode(RestrictInfo, lfirst(hcl));
+			RestrictInfo *restrictinfo = lfirst_node(RestrictInfo, hcl);
 			Selectivity thisbucketsize;
 
 			/*
@@ -3760,7 +3760,7 @@ compute_semi_anti_join_factors(PlannerInfo *root,
 		joinquals = NIL;
 		foreach(l, restrictlist)
 		{
-			RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(l));
+			RestrictInfo *rinfo = lfirst_node(RestrictInfo, l);
 
 			if (!rinfo->is_pushed_down)
 				joinquals = lappend(joinquals, rinfo);
@@ -4192,7 +4192,7 @@ calc_joinrel_size_estimate(PlannerInfo *root,
 		/* Grovel through the clauses to separate into two lists */
 		foreach(l, restrictlist)
 		{
-			RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(l));
+			RestrictInfo *rinfo = lfirst_node(RestrictInfo, l);
 
 			if (rinfo->is_pushed_down)
 				pushedquals = lappend(pushedquals, rinfo);
@@ -4568,7 +4568,7 @@ set_subquery_size_estimates(PlannerInfo *root, RelOptInfo *rel)
 	 */
 	foreach(lc, subroot->parse->targetList)
 	{
-		TargetEntry *te = castNode(TargetEntry, lfirst(lc));
+		TargetEntry *te = lfirst_node(TargetEntry, lc);
 		Node	   *texpr = (Node *) te->expr;
 		int32		item_width = 0;
 

src/backend/optimizer/path/indxpath.c

@@ -1277,7 +1277,7 @@ generate_bitmap_or_paths(PlannerInfo *root, RelOptInfo *rel,
 
 	foreach(lc, clauses)
 	{
-		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(lc));
+		RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc);
 		List	   *pathlist;
 		Path	   *bitmapqual;
 		ListCell   *j;
@@ -2188,7 +2188,7 @@ match_clauses_to_index(IndexOptInfo *index,
 
 	foreach(lc, clauses)
 	{
-		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(lc));
+		RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc);
 
 		match_clause_to_index(index, rinfo, clauseset);
 	}

src/backend/optimizer/path/joinrels.c

@@ -1250,7 +1250,7 @@ restriction_is_constant_false(List *restrictlist, bool only_pushed_down)
 	 */
 	foreach(lc, restrictlist)
 	{
-		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(lc));
+		RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc);
 
 		if (only_pushed_down && !rinfo->is_pushed_down)
 			continue;

src/backend/optimizer/plan/analyzejoins.c

@@ -601,7 +601,7 @@ rel_is_distinct_for(PlannerInfo *root, RelOptInfo *rel, List *clause_list)
 		 */
 		foreach(l, clause_list)
 		{
-			RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(l));
+			RestrictInfo *rinfo = lfirst_node(RestrictInfo, l);
 			Oid			op;
 			Var		   *var;
 

src/backend/optimizer/plan/createplan.c

@@ -2550,7 +2550,7 @@ create_indexscan_plan(PlannerInfo *root,
 	qpqual = NIL;
 	foreach(l, scan_clauses)
 	{
-		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(l));
+		RestrictInfo *rinfo = lfirst_node(RestrictInfo, l);
 
 		if (rinfo->pseudoconstant)
 			continue;			/* we may drop pseudoconstants here */
@@ -2710,7 +2710,7 @@ create_bitmap_scan_plan(PlannerInfo *root,
 	qpqual = NIL;
 	foreach(l, scan_clauses)
 	{
-		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(l));
+		RestrictInfo *rinfo = lfirst_node(RestrictInfo, l);
 		Node	   *clause = (Node *) rinfo->clause;
 
 		if (rinfo->pseudoconstant)
@@ -3867,7 +3867,7 @@ create_mergejoin_plan(PlannerInfo *root,
 	i = 0;
 	foreach(lc, best_path->path_mergeclauses)
 	{
-		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(lc));
+		RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc);
 		EquivalenceClass *oeclass;
 		EquivalenceClass *ieclass;
 		PathKey    *opathkey;
@@ -4414,7 +4414,7 @@ fix_indexqual_references(PlannerInfo *root, IndexPath *index_path)
 
 	forboth(lcc, index_path->indexquals, lci, index_path->indexqualcols)
 	{
-		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(lcc));
+		RestrictInfo *rinfo = lfirst_node(RestrictInfo, lcc);
 		int			indexcol = lfirst_int(lci);
 		Node	   *clause;
 

src/backend/optimizer/plan/planner.c

@@ -4631,7 +4631,7 @@ create_one_window_path(PlannerInfo *root,
 			window_target = copy_pathtarget(window_target);
 			foreach(lc2, wflists->windowFuncs[wc->winref])
 			{
-				WindowFunc *wfunc = castNode(WindowFunc, lfirst(lc2));
+				WindowFunc *wfunc = lfirst_node(WindowFunc, lc2);
 
 				add_column_to_pathtarget(window_target, (Expr *) wfunc, 0);
 				window_target->width += get_typavgwidth(wfunc->wintype, -1);

src/backend/optimizer/plan/setrefs.c

@@ -224,7 +224,7 @@ set_plan_references(PlannerInfo *root, Plan *plan)
 	 */
 	foreach(lc, root->rowMarks)
 	{
-		PlanRowMark *rc = castNode(PlanRowMark, lfirst(lc));
+		PlanRowMark *rc = lfirst_node(PlanRowMark, lc);
 		PlanRowMark *newrc;
 
 		/* flat copy is enough since all fields are scalars */

src/backend/optimizer/plan/subselect.c

@@ -433,7 +433,7 @@ get_first_col_type(Plan *plan, Oid *coltype, int32 *coltypmod,
 	/* In cases such as EXISTS, tlist might be empty; arbitrarily use VOID */
 	if (plan->targetlist)
 	{
-		TargetEntry *tent = castNode(TargetEntry, linitial(plan->targetlist));
+		TargetEntry *tent = linitial_node(TargetEntry, plan->targetlist);
 
 		if (!tent->resjunk)
 		{

src/backend/optimizer/prep/prepunion.c

@@ -1750,7 +1750,7 @@ translate_col_privs(const Bitmapset *parent_privs,
 	attno = InvalidAttrNumber;
 	foreach(lc, translated_vars)
 	{
-		Var		   *var = castNode(Var, lfirst(lc));
+		Var		   *var = lfirst_node(Var, lc);
 
 		attno++;
 		if (var == NULL)		/* ignore dropped columns */

src/backend/optimizer/util/clauses.c

@@ -3090,7 +3090,7 @@ eval_const_expressions_mutator(Node *node,
 				const_true_cond = false;
 				foreach(arg, caseexpr->args)
 				{
-					CaseWhen   *oldcasewhen = castNode(CaseWhen, lfirst(arg));
+					CaseWhen   *oldcasewhen = lfirst_node(CaseWhen, arg);
 					Node	   *casecond;
 					Node	   *caseresult;
 

src/backend/optimizer/util/orclauses.c

@@ -188,7 +188,7 @@ extract_or_clause(RestrictInfo *or_rinfo, RelOptInfo *rel)
 
 			foreach(lc2, andargs)
 			{
-				RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(lc2));
+				RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc2);
 
 				if (restriction_is_or_clause(rinfo))
 				{

src/backend/optimizer/util/restrictinfo.c

@@ -335,7 +335,7 @@ get_actual_clauses(List *restrictinfo_list)
 
 	foreach(l, restrictinfo_list)
 	{
-		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(l));
+		RestrictInfo *rinfo = lfirst_node(RestrictInfo, l);
 
 		Assert(!rinfo->pseudoconstant);
 
@@ -359,7 +359,7 @@ extract_actual_clauses(List *restrictinfo_list,
 
 	foreach(l, restrictinfo_list)
 	{
-		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(l));
+		RestrictInfo *rinfo = lfirst_node(RestrictInfo, l);
 
 		if (rinfo->pseudoconstant == pseudoconstant)
 			result = lappend(result, rinfo->clause);
@@ -389,7 +389,7 @@ extract_actual_join_clauses(List *restrictinfo_list,
 
 	foreach(l, restrictinfo_list)
 	{
-		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(l));
+		RestrictInfo *rinfo = lfirst_node(RestrictInfo, l);
 
 		if (rinfo->is_pushed_down)
 		{

src/backend/parser/analyze.c

@@ -829,7 +829,7 @@ transformInsertStmt(ParseState *pstate, InsertStmt *stmt)
 		AttrNumber	attr_num;
 		TargetEntry *tle;
 
-		col = castNode(ResTarget, lfirst(icols));
+		col = lfirst_node(ResTarget, icols);
 		attr_num = (AttrNumber) lfirst_int(attnos);
 
 		tle = makeTargetEntry(expr,
@@ -954,7 +954,7 @@ transformInsertRow(ParseState *pstate, List *exprlist,
 		Expr	   *expr = (Expr *) lfirst(lc);
 		ResTarget  *col;
 
-		col = castNode(ResTarget, lfirst(icols));
+		col = lfirst_node(ResTarget, icols);
 
 		expr = transformAssignedExpr(pstate, expr,
 									 EXPR_KIND_INSERT_TARGET,
@@ -2300,7 +2300,7 @@ transformUpdateTargetList(ParseState *pstate, List *origTlist)
 		}
 		if (orig_tl == NULL)
 			elog(ERROR, "UPDATE target count mismatch --- internal error");
-		origTarget = castNode(ResTarget, lfirst(orig_tl));
+		origTarget = lfirst_node(ResTarget, orig_tl);
 
 		attrno = attnameAttNum(pstate->p_target_relation,
 							   origTarget->name, true);

src/backend/parser/gram.y

@@ -798,7 +798,7 @@ stmtmulti:	stmtmulti ';' stmt
 					if ($1 != NIL)
 					{
 						/* update length of previous stmt */
-						updateRawStmtEnd(castNode(RawStmt, llast($1)), @2);
+						updateRawStmtEnd(llast_node(RawStmt, $1), @2);
 					}
 					if ($3 != NULL)
 						$$ = lappend($1, makeRawStmt($3, @2 + 1));

src/backend/parser/parse_collate.c

@@ -514,7 +514,7 @@ assign_collations_walker(Node *node, assign_collations_context *context)
 
 				if (qtree->targetList == NIL)
 					return false;
-				tent = castNode(TargetEntry, linitial(qtree->targetList));
+				tent = linitial_node(TargetEntry, qtree->targetList);
 				if (tent->resjunk)
 					return false;
 
@@ -649,7 +649,7 @@ assign_collations_walker(Node *node, assign_collations_context *context)
 
 							foreach(lc, expr->args)
 							{
-								CaseWhen   *when = castNode(CaseWhen, lfirst(lc));
+								CaseWhen   *when = lfirst_node(CaseWhen, lc);
 
 								/*
 								 * The condition expressions mustn't affect
@@ -865,7 +865,7 @@ assign_aggregate_collations(Aggref *aggref,
 	/* Process aggregated args, holding resjunk ones at arm's length */
 	foreach(lc, aggref->args)
 	{
-		TargetEntry *tle = castNode(TargetEntry, lfirst(lc));
+		TargetEntry *tle = lfirst_node(TargetEntry, lc);
 
 		if (tle->resjunk)
 			assign_expr_collations(loccontext->pstate, (Node *) tle);
@@ -909,7 +909,7 @@ assign_ordered_set_collations(Aggref *aggref,
 	/* Process aggregated args appropriately */
 	foreach(lc, aggref->args)
 	{
-		TargetEntry *tle = castNode(TargetEntry, lfirst(lc));
+		TargetEntry *tle = lfirst_node(TargetEntry, lc);
 
 		if (merge_sort_collations)
 			(void) assign_collations_walker((Node *) tle, loccontext);

src/backend/parser/parse_expr.c

@@ -1669,7 +1669,7 @@ transformCaseExpr(ParseState *pstate, CaseExpr *c)
 	resultexprs = NIL;
 	foreach(l, c->args)
 	{
-		CaseWhen   *w = castNode(CaseWhen, lfirst(l));
+		CaseWhen   *w = lfirst_node(CaseWhen, l);
 		CaseWhen   *neww = makeNode(CaseWhen);
 		Node	   *warg;
 
@@ -2334,7 +2334,7 @@ transformXmlExpr(ParseState *pstate, XmlExpr *x)
 
 	foreach(lc, x->named_args)
 	{
-		ResTarget  *r = castNode(ResTarget, lfirst(lc));
+		ResTarget  *r = lfirst_node(ResTarget, lc);
 		Node	   *expr;
 		char	   *argname;
 

src/backend/parser/parse_node.c

@@ -337,7 +337,7 @@ transformArraySubscripts(ParseState *pstate,
 	 */
 	foreach(idx, indirection)
 	{
-		A_Indices  *ai = castNode(A_Indices, lfirst(idx));
+		A_Indices  *ai = lfirst_node(A_Indices, idx);
 		Node	   *subexpr;
 
 		if (isSlice)

src/backend/parser/parse_relation.c

@@ -931,7 +931,7 @@ markRTEForSelectPriv(ParseState *pstate, RangeTblEntry *rte,
 			JoinExpr   *j;
 
 			if (rtindex > 0 && rtindex <= list_length(pstate->p_joinexprs))
-				j = castNode(JoinExpr, list_nth(pstate->p_joinexprs, rtindex - 1));
+				j = list_nth_node(JoinExpr, pstate->p_joinexprs, rtindex - 1);
 			else
 				j = NULL;
 			if (j == NULL)

src/backend/parser/parse_type.c

@@ -478,7 +478,7 @@ TypeNameListToString(List *typenames)
 	initStringInfo(&string);
 	foreach(l, typenames)
 	{
-		TypeName   *typeName = castNode(TypeName, lfirst(l));
+		TypeName   *typeName = lfirst_node(TypeName, l);
 
 		if (l != list_head(typenames))
 			appendStringInfoChar(&string, ',');
@@ -719,7 +719,7 @@ typeStringToTypeName(const char *str)
 	 */
 	if (list_length(raw_parsetree_list) != 1)
 		goto fail;
-	stmt = (SelectStmt *) castNode(RawStmt, linitial(raw_parsetree_list))->stmt;
+	stmt = (SelectStmt *) linitial_node(RawStmt, raw_parsetree_list)->stmt;
 	if (stmt == NULL ||
 		!IsA(stmt, SelectStmt) ||
 		stmt->distinctClause != NIL ||

src/backend/parser/parse_utilcmd.c

@@ -388,7 +388,7 @@ generateSerialExtraStmts(CreateStmtContext *cxt, ColumnDef *column,
 
 	foreach(option, seqoptions)
 	{
-		DefElem    *defel = castNode(DefElem, lfirst(option));
+		DefElem    *defel = lfirst_node(DefElem, option);
 
 		if (strcmp(defel->defname, "sequence_name") == 0)
 		{
@@ -605,7 +605,7 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column)
 
 	foreach(clist, column->constraints)
 	{
-		Constraint *constraint = castNode(Constraint, lfirst(clist));
+		Constraint *constraint = lfirst_node(Constraint, clist);
 
 		switch (constraint->contype)
 		{
@@ -1635,7 +1635,7 @@ transformIndexConstraints(CreateStmtContext *cxt)
 	 */
 	foreach(lc, cxt->ixconstraints)
 	{
-		Constraint *constraint = castNode(Constraint, lfirst(lc));
+		Constraint *constraint = lfirst_node(Constraint, lc);
 
 		Assert(constraint->contype == CONSTR_PRIMARY ||
 			   constraint->contype == CONSTR_UNIQUE ||
@@ -1956,8 +1956,8 @@ transformIndexConstraint(Constraint *constraint, CreateStmtContext *cxt)
 			List	   *opname;
 
 			Assert(list_length(pair) == 2);
-			elem = castNode(IndexElem, linitial(pair));
+			elem = linitial_node(IndexElem, pair);
-			opname = castNode(List, lsecond(pair));
+			opname = lsecond_node(List, pair);
 
 			index->indexParams = lappend(index->indexParams, elem);
 			index->excludeOpNames = lappend(index->excludeOpNames, opname);
@@ -1984,7 +1984,7 @@ transformIndexConstraint(Constraint *constraint, CreateStmtContext *cxt)
 
 		foreach(columns, cxt->columns)
 		{
-			column = castNode(ColumnDef, lfirst(columns));
+			column = lfirst_node(ColumnDef, columns);
 			if (strcmp(column->colname, key) == 0)
 			{
 				found = true;
@@ -2013,7 +2013,7 @@ transformIndexConstraint(Constraint *constraint, CreateStmtContext *cxt)
 
 			foreach(inher, cxt->inhRelations)
 			{
-				RangeVar   *inh = castNode(RangeVar, lfirst(inher));
+				RangeVar   *inh = lfirst_node(RangeVar, inher);
 				Relation	rel;
 				int			count;
 
@@ -2823,7 +2823,7 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
 					 */
 					foreach(lc, castNode(List, cmd->def))
 					{
-						DefElem	   *def = castNode(DefElem, lfirst(lc));
+						DefElem	   *def = lfirst_node(DefElem, lc);
 
 						if (strcmp(def->defname, "generated") == 0)
 							newdef = lappend(newdef, def);
@@ -2900,7 +2900,7 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
 	 */
 	foreach(l, cxt.alist)
 	{
-		IndexStmt  *idxstmt = castNode(IndexStmt, lfirst(l));
+		IndexStmt  *idxstmt = lfirst_node(IndexStmt, l);
 
 		idxstmt = transformIndexStmt(relid, idxstmt, queryString);
 		newcmd = makeNode(AlterTableCmd);

src/backend/rewrite/rewriteDefine.c

@@ -171,7 +171,7 @@ InsertRule(char *rulname,
 	if (event_qual != NULL)
 	{
 		/* Find query containing OLD/NEW rtable entries */
-		Query	   *qry = castNode(Query, linitial(action));
+		Query	   *qry = linitial_node(Query, action);
 
 		qry = getInsertSelectQuery(qry, NULL);
 		recordDependencyOnExpr(&myself, event_qual, qry->rtable,
@@ -284,7 +284,7 @@ DefineQueryRewrite(char *rulename,
 	 */
 	foreach(l, action)
 	{
-		query = castNode(Query, lfirst(l));
+		query = lfirst_node(Query, l);
 		if (query->resultRelation == 0)
 			continue;
 		/* Don't be fooled by INSERT/SELECT */
@@ -326,7 +326,7 @@ DefineQueryRewrite(char *rulename,
 		/*
 		 * ... the one action must be a SELECT, ...
 		 */
-		query = castNode(Query, linitial(action));
+		query = linitial_node(Query, action);
 		if (!is_instead ||
 			query->commandType != CMD_SELECT)
 			ereport(ERROR,
@@ -480,7 +480,7 @@ DefineQueryRewrite(char *rulename,
 
 		foreach(l, action)
 		{
-			query = castNode(Query, lfirst(l));
+			query = lfirst_node(Query, l);
 
 			if (!query->returningList)
 				continue;

src/backend/rewrite/rewriteHandler.c

@@ -2367,7 +2367,7 @@ view_cols_are_auto_updatable(Query *viewquery,
 	 * there should be a single base relation.
 	 */
 	Assert(list_length(viewquery->jointree->fromlist) == 1);
-	rtr = castNode(RangeTblRef, linitial(viewquery->jointree->fromlist));
+	rtr = linitial_node(RangeTblRef, viewquery->jointree->fromlist);
 
 	/* Initialize the optional return values */
 	if (updatable_cols != NULL)
@@ -2619,7 +2619,7 @@ adjust_view_column_set(Bitmapset *cols, List *targetlist)
 
 			foreach(lc, targetlist)
 			{
-				TargetEntry *tle = (TargetEntry *) lfirst(lc);
+				TargetEntry *tle = lfirst_node(TargetEntry, lc);
 				Var		   *var;
 
 				if (tle->resjunk)
@@ -2806,7 +2806,7 @@ rewriteTargetView(Query *parsetree, Relation view)
 	 * view contains a single base relation.
 	 */
 	Assert(list_length(viewquery->jointree->fromlist) == 1);
-	rtr = castNode(RangeTblRef, linitial(viewquery->jointree->fromlist));
+	rtr = linitial_node(RangeTblRef, viewquery->jointree->fromlist);
 
 	base_rt_index = rtr->rtindex;
 	base_rte = rt_fetch(base_rt_index, viewquery->rtable);
@@ -3162,7 +3162,7 @@ RewriteQuery(Query *parsetree, List *rewrite_events)
 	 */
 	foreach(lc1, parsetree->cteList)
 	{
-		CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc1);
+		CommonTableExpr *cte = lfirst_node(CommonTableExpr, lc1);
 		Query	   *ctequery = castNode(Query, cte->ctequery);
 		List	   *newstuff;
 
@@ -3179,7 +3179,7 @@ RewriteQuery(Query *parsetree, List *rewrite_events)
 		if (list_length(newstuff) == 1)
 		{
 			/* Push the single Query back into the CTE node */
-			ctequery = castNode(Query, linitial(newstuff));
+			ctequery = linitial_node(Query, newstuff);
 			/* WITH queries should never be canSetTag */
 			Assert(!ctequery->canSetTag);
 			cte->ctequery = (Node *) ctequery;

src/backend/tcop/postgres.c

@@ -850,7 +850,7 @@ pg_plan_queries(List *querytrees, int cursorOptions, ParamListInfo boundParams)
 
 	foreach(query_list, querytrees)
 	{
-		Query	   *query = castNode(Query, lfirst(query_list));
+		Query	   *query = lfirst_node(Query, query_list);
 		PlannedStmt *stmt;
 
 		if (query->commandType == CMD_UTILITY)
@@ -966,7 +966,7 @@ exec_simple_query(const char *query_string)
 	 */
 	foreach(parsetree_item, parsetree_list)
 	{
-		RawStmt    *parsetree = castNode(RawStmt, lfirst(parsetree_item));
+		RawStmt    *parsetree = lfirst_node(RawStmt, parsetree_item);
 		bool		snapshot_set = false;
 		const char *commandTag;
 		char		completionTag[COMPLETION_TAG_BUFSIZE];
@@ -1291,7 +1291,7 @@ exec_parse_message(const char *query_string,	/* string to execute */
 		bool		snapshot_set = false;
 		int			i;
 
-		raw_parse_tree = castNode(RawStmt, linitial(parsetree_list));
+		raw_parse_tree = linitial_node(RawStmt, parsetree_list);
 
 		/*
 		 * Get the command name for possible use in status display.
@@ -2154,7 +2154,7 @@ errdetail_execute(List *raw_parsetree_list)
 
 	foreach(parsetree_item, raw_parsetree_list)
 	{
-		RawStmt    *parsetree = castNode(RawStmt, lfirst(parsetree_item));
+		RawStmt    *parsetree = lfirst_node(RawStmt, parsetree_item);
 
 		if (IsA(parsetree->stmt, ExecuteStmt))
 		{
@@ -2508,7 +2508,7 @@ IsTransactionExitStmtList(List *pstmts)
 {
 	if (list_length(pstmts) == 1)
 	{
-		PlannedStmt *pstmt = castNode(PlannedStmt, linitial(pstmts));
+		PlannedStmt *pstmt = linitial_node(PlannedStmt, pstmts);
 
 		if (pstmt->commandType == CMD_UTILITY &&
 			IsTransactionExitStmt(pstmt->utilityStmt))
@@ -2523,7 +2523,7 @@ IsTransactionStmtList(List *pstmts)
 {
 	if (list_length(pstmts) == 1)
 	{
-		PlannedStmt *pstmt = castNode(PlannedStmt, linitial(pstmts));
+		PlannedStmt *pstmt = linitial_node(PlannedStmt, pstmts);
 
 		if (pstmt->commandType == CMD_UTILITY &&
 			IsA(pstmt->utilityStmt, TransactionStmt))

src/backend/tcop/pquery.c

@@ -496,7 +496,7 @@ PortalStart(Portal portal, ParamListInfo params,
 				 * Create QueryDesc in portal's context; for the moment, set
 				 * the destination to DestNone.
 				 */
-				queryDesc = CreateQueryDesc(castNode(PlannedStmt, linitial(portal->stmts)),
+				queryDesc = CreateQueryDesc(linitial_node(PlannedStmt, portal->stmts),
 											portal->sourceText,
 											GetActiveSnapshot(),
 											InvalidSnapshot,
@@ -1036,7 +1036,7 @@ FillPortalStore(Portal portal, bool isTopLevel)
 			break;
 
 		case PORTAL_UTIL_SELECT:
-			PortalRunUtility(portal, castNode(PlannedStmt, linitial(portal->stmts)),
+			PortalRunUtility(portal, linitial_node(PlannedStmt, portal->stmts),
 							 isTopLevel, true, treceiver, completionTag);
 			break;
 
@@ -1232,7 +1232,7 @@ PortalRunMulti(Portal portal,
 	 */
 	foreach(stmtlist_item, portal->stmts)
 	{
-		PlannedStmt *pstmt = castNode(PlannedStmt, lfirst(stmtlist_item));
+		PlannedStmt *pstmt = lfirst_node(PlannedStmt, stmtlist_item);
 
 		/*
 		 * If we got a cancel signal in prior command, quit

src/backend/utils/adt/ruleutils.c

@@ -7809,7 +7809,7 @@ get_rule_expr(Node *node, deparse_context *context,
 				appendStringInfoString(buf, "(alternatives: ");
 				foreach(lc, asplan->subplans)
 				{
-					SubPlan    *splan = castNode(SubPlan, lfirst(lc));
+					SubPlan    *splan = lfirst_node(SubPlan, lc);
 
 					if (splan->useHashTable)
 						appendStringInfo(buf, "hashed %s", splan->plan_name);
@@ -8364,7 +8364,7 @@ get_rule_expr(Node *node, deparse_context *context,
 							get_rule_expr((Node *) linitial(xexpr->args),
 										  context, true);
 
-							con = castNode(Const, lsecond(xexpr->args));
+							con = lsecond_node(Const, xexpr->args);
 							Assert(!con->constisnull);
 							if (DatumGetBool(con->constvalue))
 								appendStringInfoString(buf,
@@ -8387,7 +8387,7 @@ get_rule_expr(Node *node, deparse_context *context,
 							else
 								get_rule_expr((Node *) con, context, false);
 
-							con = castNode(Const, lthird(xexpr->args));
+							con = lthird_node(Const, xexpr->args);
 							if (con->constisnull)
 								 /* suppress STANDALONE NO VALUE */ ;
 							else
@@ -8899,7 +8899,7 @@ get_agg_expr(Aggref *aggref, deparse_context *context,
 	 */
 	if (DO_AGGSPLIT_COMBINE(aggref->aggsplit))
 	{
-		TargetEntry *tle = castNode(TargetEntry, linitial(aggref->args));
+		TargetEntry *tle = linitial_node(TargetEntry, aggref->args);
 
 		Assert(list_length(aggref->args) == 1);
 		resolve_special_varno((Node *) tle->expr, context, original_aggref,
@@ -9360,7 +9360,7 @@ get_sublink_expr(SubLink *sublink, deparse_context *context)
 			sep = "";
 			foreach(l, ((BoolExpr *) sublink->testexpr)->args)
 			{
-				OpExpr	   *opexpr = castNode(OpExpr, lfirst(l));
+				OpExpr	   *opexpr = lfirst_node(OpExpr, l);
 
 				appendStringInfoString(buf, sep);
 				get_rule_expr(linitial(opexpr->args), context, true);

src/backend/utils/adt/selfuncs.c

@@ -6243,7 +6243,7 @@ deconstruct_indexquals(IndexPath *path)
 
 	forboth(lcc, path->indexquals, lci, path->indexqualcols)
 	{
-		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(lcc));
+		RestrictInfo *rinfo = lfirst_node(RestrictInfo, lcc);
 		int			indexcol = lfirst_int(lci);
 		Expr	   *clause;
 		Node	   *leftop,

src/backend/utils/cache/plancache.c

@@ -979,7 +979,7 @@ BuildCachedPlan(CachedPlanSource *plansource, List *qlist,
 	is_transient = false;
 	foreach(lc, plist)
 	{
-		PlannedStmt *plannedstmt = castNode(PlannedStmt, lfirst(lc));
+		PlannedStmt *plannedstmt = lfirst_node(PlannedStmt, lc);
 
 		if (plannedstmt->commandType == CMD_UTILITY)
 			continue;			/* Ignore utility statements */
@@ -1074,7 +1074,7 @@ cached_plan_cost(CachedPlan *plan, bool include_planner)
 
 	foreach(lc, plan->stmt_list)
 	{
-		PlannedStmt *plannedstmt = castNode(PlannedStmt, lfirst(lc));
+		PlannedStmt *plannedstmt = lfirst_node(PlannedStmt, lc);
 
 		if (plannedstmt->commandType == CMD_UTILITY)
 			continue;			/* Ignore utility statements */
@@ -1462,7 +1462,7 @@ QueryListGetPrimaryStmt(List *stmts)
 
 	foreach(lc, stmts)
 	{
-		Query	   *stmt = castNode(Query, lfirst(lc));
+		Query	   *stmt = lfirst_node(Query, lc);
 
 		if (stmt->canSetTag)
 			return stmt;
@@ -1481,7 +1481,7 @@ AcquireExecutorLocks(List *stmt_list, bool acquire)
 
 	foreach(lc1, stmt_list)
 	{
-		PlannedStmt *plannedstmt = castNode(PlannedStmt, lfirst(lc1));
+		PlannedStmt *plannedstmt = lfirst_node(PlannedStmt, lc1);
 		int			rt_index;
 		ListCell   *lc2;
 
@@ -1551,7 +1551,7 @@ AcquirePlannerLocks(List *stmt_list, bool acquire)
 
 	foreach(lc, stmt_list)
 	{
-		Query	   *query = castNode(Query, lfirst(lc));
+		Query	   *query = lfirst_node(Query, lc);
 
 		if (query->commandType == CMD_UTILITY)
 		{
@@ -1618,7 +1618,7 @@ ScanQueryForLocks(Query *parsetree, bool acquire)
 	/* Recurse into subquery-in-WITH */
 	foreach(lc, parsetree->cteList)
 	{
-		CommonTableExpr *cte = castNode(CommonTableExpr, lfirst(lc));
+		CommonTableExpr *cte = lfirst_node(CommonTableExpr, lc);
 
 		ScanQueryForLocks(castNode(Query, cte->ctequery), acquire);
 	}
@@ -1676,7 +1676,7 @@ PlanCacheComputeResultDesc(List *stmt_list)
 	{
 		case PORTAL_ONE_SELECT:
 		case PORTAL_ONE_MOD_WITH:
-			query = castNode(Query, linitial(stmt_list));
+			query = linitial_node(Query, stmt_list);
 			return ExecCleanTypeFromTL(query->targetList, false);
 
 		case PORTAL_ONE_RETURNING:
@@ -1685,7 +1685,7 @@ PlanCacheComputeResultDesc(List *stmt_list)
 			return ExecCleanTypeFromTL(query->returningList, false);
 
 		case PORTAL_UTIL_SELECT:
-			query = castNode(Query, linitial(stmt_list));
+			query = linitial_node(Query, stmt_list);
 			Assert(query->utilityStmt);
 			return UtilityTupleDescriptor(query->utilityStmt);
 
@@ -1742,7 +1742,7 @@ PlanCacheRelCallback(Datum arg, Oid relid)
 
 			foreach(lc, plansource->gplan->stmt_list)
 			{
-				PlannedStmt *plannedstmt = castNode(PlannedStmt, lfirst(lc));
+				PlannedStmt *plannedstmt = lfirst_node(PlannedStmt, lc);
 
 				if (plannedstmt->commandType == CMD_UTILITY)
 					continue;	/* Ignore utility statements */
@@ -1815,7 +1815,7 @@ PlanCacheFuncCallback(Datum arg, int cacheid, uint32 hashvalue)
 		{
 			foreach(lc, plansource->gplan->stmt_list)
 			{
-				PlannedStmt *plannedstmt = castNode(PlannedStmt, lfirst(lc));
+				PlannedStmt *plannedstmt = lfirst_node(PlannedStmt, lc);
 				ListCell   *lc3;
 
 				if (plannedstmt->commandType == CMD_UTILITY)
@@ -1888,7 +1888,7 @@ ResetPlanCache(void)
 		 */
 		foreach(lc, plansource->query_list)
 		{
-			Query	   *query = castNode(Query, lfirst(lc));
+			Query	   *query = lfirst_node(Query, lc);
 
 			if (query->commandType != CMD_UTILITY ||
 				UtilityContainsQuery(query->utilityStmt))

src/backend/utils/misc/guc.c

@@ -7366,7 +7366,7 @@ ExecSetVariableStmt(VariableSetStmt *stmt, bool isTopLevel)
 			}
 			else if (strcmp(stmt->name, "TRANSACTION SNAPSHOT") == 0)
 			{
-				A_Const    *con = castNode(A_Const, linitial(stmt->args));
+				A_Const    *con = linitial_node(A_Const, stmt->args);
 
 				if (stmt->is_local)
 					ereport(ERROR,

src/backend/utils/mmgr/portalmem.c

@@ -153,7 +153,7 @@ PortalGetPrimaryStmt(Portal portal)
 
 	foreach(lc, portal->stmts)
 	{
-		PlannedStmt *stmt = castNode(PlannedStmt, lfirst(lc));
+		PlannedStmt *stmt = lfirst_node(PlannedStmt, lc);
 
 		if (stmt->canSetTag)
 			return stmt;

src/include/nodes/pg_list.h

@@ -106,26 +106,32 @@ list_length(const List *l)
 #define lfirst(lc)				((lc)->data.ptr_value)
 #define lfirst_int(lc)			((lc)->data.int_value)
 #define lfirst_oid(lc)			((lc)->data.oid_value)
+#define lfirst_node(type,lc)	castNode(type, lfirst(lc))
 
 #define linitial(l)				lfirst(list_head(l))
 #define linitial_int(l)			lfirst_int(list_head(l))
 #define linitial_oid(l)			lfirst_oid(list_head(l))
+#define linitial_node(type,l)	castNode(type, linitial(l))
 
 #define lsecond(l)				lfirst(lnext(list_head(l)))
 #define lsecond_int(l)			lfirst_int(lnext(list_head(l)))
 #define lsecond_oid(l)			lfirst_oid(lnext(list_head(l)))
+#define lsecond_node(type,l)	castNode(type, lsecond(l))
 
 #define lthird(l)				lfirst(lnext(lnext(list_head(l))))
 #define lthird_int(l)			lfirst_int(lnext(lnext(list_head(l))))
 #define lthird_oid(l)			lfirst_oid(lnext(lnext(list_head(l))))
+#define lthird_node(type,l)		castNode(type, lthird(l))
 
 #define lfourth(l)				lfirst(lnext(lnext(lnext(list_head(l)))))
 #define lfourth_int(l)			lfirst_int(lnext(lnext(lnext(list_head(l)))))
 #define lfourth_oid(l)			lfirst_oid(lnext(lnext(lnext(list_head(l)))))
+#define lfourth_node(type,l)	castNode(type, lfourth(l))
 
 #define llast(l)				lfirst(list_tail(l))
 #define llast_int(l)			lfirst_int(list_tail(l))
 #define llast_oid(l)			lfirst_oid(list_tail(l))
+#define llast_node(type,l)		castNode(type, llast(l))
 
 /*
  * Convenience macros for building fixed-length lists
@@ -204,6 +210,7 @@ extern ListCell *list_nth_cell(const List *list, int n);
 extern void *list_nth(const List *list, int n);
 extern int	list_nth_int(const List *list, int n);
 extern Oid	list_nth_oid(const List *list, int n);
+#define list_nth_node(type,list,n)	castNode(type, list_nth(list, n))
 
 extern bool list_member(const List *list, const void *datum);
 extern bool list_member_ptr(const List *list, const void *datum);

src/pl/plpgsql/src/pl_exec.c

@@ -3639,7 +3639,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 
 			foreach(l2, plansource->query_list)
 			{
-				Query	   *q = castNode(Query, lfirst(l2));
+				Query	   *q = lfirst_node(Query, l2);
 
 				if (q->canSetTag)
 				{
@@ -6835,7 +6835,7 @@ exec_simple_recheck_plan(PLpgSQL_expr *expr, CachedPlan *cplan)
 	 */
 	if (list_length(cplan->stmt_list) != 1)
 		return;
-	stmt = castNode(PlannedStmt, linitial(cplan->stmt_list));
+	stmt = linitial_node(PlannedStmt, cplan->stmt_list);
 
 	/*
 	 * 2. It must be a RESULT plan --> no scan's required