1 files changed, 15 insertions, 21 deletions

diff --git a/src/backend/optimizer/plan/createplan.c b/src/backend/optimizer/plan/createplan.c
index 997bdcff2ea..1e953b40d6f 100644
--- a/src/backend/optimizer/plan/createplan.c
+++ b/src/backend/optimizer/plan/createplan.c
@@ -508,8 +508,7 @@ create_scan_plan(PlannerInfo *root, Path *best_path, int flags)
 	{
 		case T_IndexScan:
 		case T_IndexOnlyScan:
-			Assert(IsA(best_path, IndexPath));
-			scan_clauses = ((IndexPath *) best_path)->indexinfo->indrestrictinfo;
+			scan_clauses = castNode(IndexPath, best_path)->indexinfo->indrestrictinfo;
 			break;
 		default:
 			scan_clauses = rel->baserestrictinfo;
@@ -2450,9 +2449,8 @@ create_indexscan_plan(PlannerInfo *root,
 	qpqual = NIL;
 	foreach(l, scan_clauses)
 	{
-		RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
+		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(l));
 
-		Assert(IsA(rinfo, RestrictInfo));
 		if (rinfo->pseudoconstant)
 			continue;			/* we may drop pseudoconstants here */
 		if (list_member_ptr(indexquals, rinfo))
@@ -2608,10 +2606,9 @@ create_bitmap_scan_plan(PlannerInfo *root,
 	qpqual = NIL;
 	foreach(l, scan_clauses)
 	{
-		RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
+		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(l));
 		Node	   *clause = (Node *) rinfo->clause;
 
-		Assert(IsA(rinfo, RestrictInfo));
 		if (rinfo->pseudoconstant)
 			continue;			/* we may drop pseudoconstants here */
 		if (list_member(indexquals, clause))
@@ -2820,9 +2817,9 @@ create_bitmap_subplan(PlannerInfo *root, Path *bitmapqual,
 		ListCell   *l;
 
 		/* Use the regular indexscan plan build machinery... */
-		iscan = (IndexScan *) create_indexscan_plan(root, ipath,
-													NIL, NIL, false);
-		Assert(IsA(iscan, IndexScan));
+		iscan = castNode(IndexScan,
+						 create_indexscan_plan(root, ipath,
+											   NIL, NIL, false));
 		/* then convert to a bitmap indexscan */
 		plan = (Plan *) make_bitmap_indexscan(iscan->scan.scanrelid,
 											  iscan->indexid,
@@ -3391,13 +3388,13 @@ create_customscan_plan(PlannerInfo *root, CustomPath *best_path,
 	 * Invoke custom plan provider to create the Plan node represented by the
 	 * CustomPath.
 	 */
-	cplan = (CustomScan *) best_path->methods->PlanCustomPath(root,
-															  rel,
-															  best_path,
-															  tlist,
-															  scan_clauses,
-															  custom_plans);
-	Assert(IsA(cplan, CustomScan));
+	cplan = castNode(CustomScan,
+					 best_path->methods->PlanCustomPath(root,
+														rel,
+														best_path,
+														tlist,
+														scan_clauses,
+														custom_plans));
 
 	/*
 	 * Copy cost data from Path to Plan; no need to make custom-plan providers
@@ -3683,7 +3680,7 @@ create_mergejoin_plan(PlannerInfo *root,
 	i = 0;
 	foreach(lc, best_path->path_mergeclauses)
 	{
-		RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
+		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(lc));
 		EquivalenceClass *oeclass;
 		EquivalenceClass *ieclass;
 		PathKey    *opathkey;
@@ -3693,7 +3690,6 @@ create_mergejoin_plan(PlannerInfo *root,
 		ListCell   *l2;
 
 		/* fetch outer/inner eclass from mergeclause */
-		Assert(IsA(rinfo, RestrictInfo));
 		if (rinfo->outer_is_left)
 		{
 			oeclass = rinfo->left_ec;
@@ -4228,12 +4224,10 @@ fix_indexqual_references(PlannerInfo *root, IndexPath *index_path)
 
 	forboth(lcc, index_path->indexquals, lci, index_path->indexqualcols)
 	{
-		RestrictInfo *rinfo = (RestrictInfo *) lfirst(lcc);
+		RestrictInfo *rinfo = castNode(RestrictInfo, lfirst(lcc));
 		int			indexcol = lfirst_int(lci);
 		Node	   *clause;
 
-		Assert(IsA(rinfo, RestrictInfo));
-
 		/*
 		 * Replace any outer-relation variables with nestloop params.
 		 *