From dd49fa74df12eb920faf7a3051e22a186f77edbd Mon Sep 17 00:00:00 2001
From: jian he <jian.universality@gmail.com>
Date: Mon, 15 Dec 2025 12:28:40 +0800
Subject: [PATCH v16 22/23] CAST(expr AS newtype DEFAULT ON ERROR)

# Bumps catversion required.

* With this patchset, most functions in pg_cast.castfunc are now error-safe.
* CoerceViaIO and CoerceToDomain were already error-safe in the HEAD.
* this patch extends error-safe behavior to ArrayCoerceExpr.
* We also ensure that when a coercion fails, execution falls back to evaluating
the specified default node.
* The doc has been refined, though it may still need more review.

demo:
SELECT CAST('1' AS date  DEFAULT '2011-01-01' ON ERROR),
       CAST('{234,def,567}'::text[] AS integer[] DEFAULT '{-1011}' ON ERROR);
    date    |  int4
------------+---------
 2011-01-01 | {-1011}

[0]: https://git.postgresql.org/cgit/postgresql.git/commit/?id=aaaf9449ec6be62cb0d30ed3588dc384f56274b

discussion: https://postgr.es/m/CADkLM=fv1JfY4Ufa-jcwwNbjQixNViskQ8jZu3Tz_p656i_4hQ@mail.gmail.com
---
 contrib/citext/expected/citext.out            |   5 +
 contrib/citext/expected/citext_1.out          |   5 +
 contrib/citext/sql/citext.sql                 |   2 +
 .../pg_stat_statements/expected/select.out    |  23 +-
 contrib/pg_stat_statements/sql/select.sql     |   5 +
 doc/src/sgml/syntax.sgml                      |  30 +
 src/backend/executor/execExpr.c               | 109 ++-
 src/backend/executor/execExprInterp.c         |  29 +
 src/backend/jit/llvm/llvmjit_expr.c           |  26 +
 src/backend/nodes/nodeFuncs.c                 |  61 ++
 src/backend/optimizer/util/clauses.c          |  51 +-
 src/backend/parser/gram.y                     |  22 +
 src/backend/parser/parse_agg.c                |   9 +
 src/backend/parser/parse_coerce.c             |  78 +-
 src/backend/parser/parse_expr.c               | 412 ++++++++-
 src/backend/parser/parse_func.c               |   3 +
 src/backend/parser/parse_target.c             |  14 +
 src/backend/parser/parse_type.c               |  14 +
 src/backend/parser/parse_utilcmd.c            |   2 +-
 src/backend/utils/adt/arrayfuncs.c            |   8 +
 src/backend/utils/adt/ruleutils.c             |  21 +
 src/backend/utils/fmgr/fmgr.c                 |  14 +
 src/include/executor/execExpr.h               |   7 +
 src/include/executor/executor.h               |   1 +
 src/include/fmgr.h                            |   3 +
 src/include/nodes/execnodes.h                 |  21 +
 src/include/nodes/parsenodes.h                |  11 +
 src/include/nodes/primnodes.h                 |  36 +
 src/include/optimizer/optimizer.h             |   2 +-
 src/include/parser/parse_coerce.h             |  15 +
 src/include/parser/parse_node.h               |   2 +
 src/include/parser/parse_type.h               |   2 +
 src/test/regress/expected/cast.out            | 810 ++++++++++++++++++
 src/test/regress/expected/create_cast.out     |   5 +
 src/test/regress/expected/equivclass.out      |   7 +
 src/test/regress/parallel_schedule            |   2 +-
 src/test/regress/sql/cast.sql                 | 350 ++++++++
 src/test/regress/sql/create_cast.sql          |   1 +
 src/test/regress/sql/equivclass.sql           |   3 +
 src/tools/pgindent/typedefs.list              |   3 +
 40 files changed, 2179 insertions(+), 45 deletions(-)
 create mode 100644 src/test/regress/expected/cast.out
 create mode 100644 src/test/regress/sql/cast.sql

diff --git a/contrib/citext/expected/citext.out b/contrib/citext/expected/citext.out
index 8c0bf54f0f3..33da19d8df4 100644
--- a/contrib/citext/expected/citext.out
+++ b/contrib/citext/expected/citext.out
@@ -10,6 +10,11 @@ WHERE opc.oid >= 16384 AND NOT amvalidate(opc.oid);
 --------+---------
 (0 rows)
 
+SELECT CAST('abc'::bpchar AS citext DEFAULT NULL ON CONVERSION ERROR); --error
+ERROR:  cannot cast type character to citext when DEFAULT expression is specified in CAST ... ON CONVERSION ERROR
+LINE 1: SELECT CAST('abc'::bpchar AS citext DEFAULT NULL ON CONVERSI...
+                    ^
+HINT:  Safe type cast for user-defined types are not yet supported
 -- Test the operators and indexing functions
 -- Test = and <>.
 SELECT 'a'::citext = 'a'::citext AS t;
diff --git a/contrib/citext/expected/citext_1.out b/contrib/citext/expected/citext_1.out
index c5e5f180f2b..647eea19142 100644
--- a/contrib/citext/expected/citext_1.out
+++ b/contrib/citext/expected/citext_1.out
@@ -10,6 +10,11 @@ WHERE opc.oid >= 16384 AND NOT amvalidate(opc.oid);
 --------+---------
 (0 rows)
 
+SELECT CAST('abc'::bpchar AS citext DEFAULT NULL ON CONVERSION ERROR); --error
+ERROR:  cannot cast type character to citext when DEFAULT expression is specified in CAST ... ON CONVERSION ERROR
+LINE 1: SELECT CAST('abc'::bpchar AS citext DEFAULT NULL ON CONVERSI...
+                    ^
+HINT:  Safe type cast for user-defined types are not yet supported
 -- Test the operators and indexing functions
 -- Test = and <>.
 SELECT 'a'::citext = 'a'::citext AS t;
diff --git a/contrib/citext/sql/citext.sql b/contrib/citext/sql/citext.sql
index aa1cf9abd5c..99794497d47 100644
--- a/contrib/citext/sql/citext.sql
+++ b/contrib/citext/sql/citext.sql
@@ -9,6 +9,8 @@ SELECT amname, opcname
 FROM pg_opclass opc LEFT JOIN pg_am am ON am.oid = opcmethod
 WHERE opc.oid >= 16384 AND NOT amvalidate(opc.oid);
 
+SELECT CAST('abc'::bpchar AS citext DEFAULT NULL ON CONVERSION ERROR); --error
+
 -- Test the operators and indexing functions
 
 -- Test = and <>.
diff --git a/contrib/pg_stat_statements/expected/select.out b/contrib/pg_stat_statements/expected/select.out
index 75c896f3885..6e67997f0a2 100644
--- a/contrib/pg_stat_statements/expected/select.out
+++ b/contrib/pg_stat_statements/expected/select.out
@@ -73,6 +73,25 @@ SELECT 1 AS "int" OFFSET 2 FETCH FIRST 3 ROW ONLY;
 -----
 (0 rows)
 
+--error safe type cast
+SELECT CAST('a' AS int DEFAULT 2 ON CONVERSION ERROR);
+ int4 
+------
+    2
+(1 row)
+
+SELECT CAST('11' AS int DEFAULT 2 ON CONVERSION ERROR);
+ int4 
+------
+   11
+(1 row)
+
+SELECT CAST('12' AS numeric DEFAULT 2 ON CONVERSION ERROR);
+ numeric 
+---------
+      12
+(1 row)
+
 -- DISTINCT and ORDER BY patterns
 -- Try some query permutations which once produced identical query IDs
 SELECT DISTINCT 1 AS "int";
@@ -222,6 +241,8 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
      2 |    2 | SELECT $1 AS "int" ORDER BY 1
      1 |    2 | SELECT $1 AS i UNION SELECT $2 ORDER BY i
      1 |    1 | SELECT $1 || $2
+     2 |    2 | SELECT CAST($1 AS int DEFAULT $2 ON CONVERSION ERROR)
+     1 |    1 | SELECT CAST($1 AS numeric DEFAULT $2 ON CONVERSION ERROR)
      2 |    2 | SELECT DISTINCT $1 AS "int"
      0 |    0 | SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C"
      1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
@@ -230,7 +251,7 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
        |      | )                                                                           +
        |      |   SELECT f FROM t ORDER BY f
      1 |    1 | select $1::jsonb ? $2
-(17 rows)
+(19 rows)
 
 SELECT pg_stat_statements_reset() IS NOT NULL AS t;
  t 
diff --git a/contrib/pg_stat_statements/sql/select.sql b/contrib/pg_stat_statements/sql/select.sql
index 11662cde08c..7ee8160fd84 100644
--- a/contrib/pg_stat_statements/sql/select.sql
+++ b/contrib/pg_stat_statements/sql/select.sql
@@ -25,6 +25,11 @@ SELECT 1 AS "int" LIMIT 3 OFFSET 3;
 SELECT 1 AS "int" OFFSET 1 FETCH FIRST 2 ROW ONLY;
 SELECT 1 AS "int" OFFSET 2 FETCH FIRST 3 ROW ONLY;
 
+--error safe type cast
+SELECT CAST('a' AS int DEFAULT 2 ON CONVERSION ERROR);
+SELECT CAST('11' AS int DEFAULT 2 ON CONVERSION ERROR);
+SELECT CAST('12' AS numeric DEFAULT 2 ON CONVERSION ERROR);
+
 -- DISTINCT and ORDER BY patterns
 -- Try some query permutations which once produced identical query IDs
 SELECT DISTINCT 1 AS "int";
diff --git a/doc/src/sgml/syntax.sgml b/doc/src/sgml/syntax.sgml
index 34c83880a66..32af9ea061c 100644
--- a/doc/src/sgml/syntax.sgml
+++ b/doc/src/sgml/syntax.sgml
@@ -2106,6 +2106,10 @@ CAST ( <replaceable>expression</replaceable> AS <replaceable>type</replaceable>
     The <literal>CAST</literal> syntax conforms to SQL; the syntax with
     <literal>::</literal> is historical <productname>PostgreSQL</productname>
     usage.
+    The equivalent ON CONVERSION ERROR behavior is:
+<synopsis>
+CAST ( <replaceable>expression</replaceable> AS <replaceable>type</replaceable> ERROR ON CONVERSION ERROR )
+</synopsis>
    </para>
 
    <para>
@@ -2160,6 +2164,32 @@ CAST ( <replaceable>expression</replaceable> AS <replaceable>type</replaceable>
      <xref linkend="sql-createcast"/>.
     </para>
    </note>
+
+ <sect3 id="sql-syntax-type-casts-safe">
+  <title>Safe Type Cast</title>
+   <para>
+    A type cast may occasionally fail. To guard against such failures, you can
+    provide an <literal>ON ERROR</literal> clause to handle potential errors.
+    The syntax for safe type cast is:
+<synopsis>
+CAST ( <replaceable>expression</replaceable> AS <replaceable>type</replaceable> DEFAULT <replaceable>expression</replaceable> ON CONVERSION ERROR )
+</synopsis>
+    If the type cast fails, instead of error out, evaluation falls back to the
+    default <replaceable>expression</replaceable> specified in the <literal>ON ERROR</literal> clause.
+    At present, this only support built-in type casts; see <xref linkend="catalog-pg-cast"/>.
+    User-defined type casts created with <link linkend="sql-createcast">CREATE CAST</link> are not supported.
+  </para>
+
+    <para>
+    Some examples:
+<screen>
+SELECT CAST(TEXT 'error' AS integer DEFAULT 3 ON CONVERSION ERROR);
+<lineannotation>Result: </lineannotation><computeroutput>3</computeroutput>
+SELECT CAST(TEXT 'error' AS numeric DEFAULT 1.1 ON CONVERSION ERROR);
+<lineannotation>Result: </lineannotation><computeroutput>1.1</computeroutput>
+</screen>
+    </para>
+  </sect3>
   </sect2>
 
   <sect2 id="sql-syntax-collate-exprs">
diff --git a/src/backend/executor/execExpr.c b/src/backend/executor/execExpr.c
index c35744b105e..12ec679b90b 100644
--- a/src/backend/executor/execExpr.c
+++ b/src/backend/executor/execExpr.c
@@ -99,6 +99,9 @@ static void ExecBuildAggTransCall(ExprState *state, AggState *aggstate,
 static void ExecInitJsonExpr(JsonExpr *jsexpr, ExprState *state,
 							 Datum *resv, bool *resnull,
 							 ExprEvalStep *scratch);
+static void ExecInitSafeTypeCastExpr(SafeTypeCastExpr *stcexpr, ExprState *state,
+									 Datum *resv, bool *resnull,
+									 ExprEvalStep *scratch);
 static void ExecInitJsonCoercion(ExprState *state, JsonReturning *returning,
 								 ErrorSaveContext *escontext, bool omit_quotes,
 								 bool exists_coerce,
@@ -170,6 +173,47 @@ ExecInitExpr(Expr *node, PlanState *parent)
 	return state;
 }
 
+/*
+ * ExecInitExprSafe: soft error variant of ExecInitExpr.
+ *
+ * use it only for expression nodes support soft errors, not all expression
+ * nodes support it.
+*/
+ExprState *
+ExecInitExprSafe(Expr *node, PlanState *parent)
+{
+	ExprState  *state;
+	ExprEvalStep scratch = {0};
+
+	/* Special case: NULL expression produces a NULL ExprState pointer */
+	if (node == NULL)
+		return NULL;
+
+	/* Initialize ExprState with empty step list */
+	state = makeNode(ExprState);
+	state->expr = node;
+	state->parent = parent;
+	state->ext_params = NULL;
+	state->escontext = makeNode(ErrorSaveContext);
+	state->escontext->type = T_ErrorSaveContext;
+	state->escontext->error_occurred = false;
+	state->escontext->details_wanted = false;
+
+	/* Insert setup steps as needed */
+	ExecCreateExprSetupSteps(state, (Node *) node);
+
+	/* Compile the expression proper */
+	ExecInitExprRec(node, state, &state->resvalue, &state->resnull);
+
+	/* Finally, append a DONE step */
+	scratch.opcode = EEOP_DONE_RETURN;
+	ExprEvalPushStep(state, &scratch);
+
+	ExecReadyExpr(state);
+
+	return state;
+}
+
 /*
  * ExecInitExprWithParams: prepare a standalone expression tree for execution
  *
@@ -1701,6 +1745,7 @@ ExecInitExprRec(Expr *node, ExprState *state,
 
 				elemstate->innermost_caseval = palloc_object(Datum);
 				elemstate->innermost_casenull = palloc_object(bool);
+				elemstate->escontext = state->escontext;
 
 				ExecInitExprRec(acoerce->elemexpr, elemstate,
 								&elemstate->resvalue, &elemstate->resnull);
@@ -2176,6 +2221,14 @@ ExecInitExprRec(Expr *node, ExprState *state,
 				break;
 			}
 
+		case T_SafeTypeCastExpr:
+			{
+				SafeTypeCastExpr   *stcexpr = castNode(SafeTypeCastExpr, node);
+
+				ExecInitSafeTypeCastExpr(stcexpr, state, resv, resnull, &scratch);
+				break;
+			}
+
 		case T_CoalesceExpr:
 			{
 				CoalesceExpr *coalesce = (CoalesceExpr *) node;
@@ -2736,7 +2789,7 @@ ExecInitFunc(ExprEvalStep *scratch, Expr *node, List *args, Oid funcid,
 
 	/* Initialize function call parameter structure too */
 	InitFunctionCallInfoData(*fcinfo, flinfo,
-							 nargs, inputcollid, NULL, NULL);
+							 nargs, inputcollid, (Node *) state->escontext, NULL);
 
 	/* Keep extra copies of this info to save an indirection at runtime */
 	scratch->d.func.fn_addr = flinfo->fn_addr;
@@ -4733,6 +4786,60 @@ ExecBuildParamSetEqual(TupleDesc desc,
 	return state;
 }
 
+/*
+ * Push steps to evaluate a SafeTypeCastExpr and its various subsidiary
+ * expressions.
+ */
+static void
+ExecInitSafeTypeCastExpr(SafeTypeCastExpr *stcexpr , ExprState *state,
+						 Datum *resv, bool *resnull,
+						 ExprEvalStep *scratch)
+{
+	/*
+	 * If we can not coerce to the target type, fallback to the DEFAULT
+	 * expression specified in the ON CONVERSION ERROR clause, and we are done.
+	 */
+	if (stcexpr->cast_expr == NULL)
+	{
+		ExecInitExprRec((Expr *) stcexpr->default_expr,
+						state, resv, resnull);
+		return;
+	}
+	else
+	{
+		SafeTypeCastState *stcstate;
+
+		stcstate = palloc0(sizeof(SafeTypeCastState));
+		stcstate->stcexpr = stcexpr;
+		stcstate->escontext.type = T_ErrorSaveContext;
+		state->escontext = &stcstate->escontext;
+
+		/* evaluate argument expression into step's result area */
+		ExecInitExprRec((Expr *) stcexpr->cast_expr,
+						state, resv, resnull);
+		scratch->opcode = EEOP_SAFETYPE_CAST;
+		scratch->d.stcexpr.stcstate = stcstate;
+		ExprEvalPushStep(state, scratch);
+
+		/*
+		 * Steps to evaluate the DEFAULT expression.  Skip it if this is a
+		 * binary coercion cast.
+		 */
+		if (!IsA(stcexpr->cast_expr, RelabelType))
+		{
+			ErrorSaveContext *saved_escontext;
+
+			saved_escontext = state->escontext;
+			state->escontext = NULL;
+			ExecInitExprRec((Expr *) stcstate->stcexpr->default_expr,
+							state, resv, resnull);
+			state->escontext = saved_escontext;
+		}
+
+		stcstate->jump_end = state->steps_len;
+	}
+}
+
 /*
  * Push steps to evaluate a JsonExpr and its various subsidiary expressions.
  */
diff --git a/src/backend/executor/execExprInterp.c b/src/backend/executor/execExprInterp.c
index 1d88cdd2cb4..ca6e0fd56cd 100644
--- a/src/backend/executor/execExprInterp.c
+++ b/src/backend/executor/execExprInterp.c
@@ -568,6 +568,7 @@ ExecInterpExpr(ExprState *state, ExprContext *econtext, bool *isnull)
 		&&CASE_EEOP_XMLEXPR,
 		&&CASE_EEOP_JSON_CONSTRUCTOR,
 		&&CASE_EEOP_IS_JSON,
+		&&CASE_EEOP_SAFETYPE_CAST,
 		&&CASE_EEOP_JSONEXPR_PATH,
 		&&CASE_EEOP_JSONEXPR_COERCION,
 		&&CASE_EEOP_JSONEXPR_COERCION_FINISH,
@@ -1926,6 +1927,28 @@ ExecInterpExpr(ExprState *state, ExprContext *econtext, bool *isnull)
 			EEO_NEXT();
 		}
 
+		EEO_CASE(EEOP_SAFETYPE_CAST)
+		{
+			SafeTypeCastState *stcstate = op->d.stcexpr.stcstate;
+
+			if (SOFT_ERROR_OCCURRED(&stcstate->escontext))
+			{
+				*op->resvalue = (Datum) 0;
+				*op->resnull = true;
+
+				/*
+				 * Reset for next use such as for catching errors when coercing
+				 * a expression.
+				 */
+				stcstate->escontext.error_occurred = false;
+				stcstate->escontext.details_wanted = false;
+
+				EEO_NEXT();
+			}
+			else
+				EEO_JUMP(stcstate->jump_end);
+		}
+
 		EEO_CASE(EEOP_JSONEXPR_PATH)
 		{
 			/* too complex for an inline implementation */
@@ -3644,6 +3667,12 @@ ExecEvalArrayCoerce(ExprState *state, ExprEvalStep *op, ExprContext *econtext)
 							  econtext,
 							  op->d.arraycoerce.resultelemtype,
 							  op->d.arraycoerce.amstate);
+
+	if (SOFT_ERROR_OCCURRED(op->d.arraycoerce.elemexprstate->escontext))
+	{
+		*op->resvalue = (Datum) 0;
+		*op->resnull = true;
+	}
 }
 
 /*
diff --git a/src/backend/jit/llvm/llvmjit_expr.c b/src/backend/jit/llvm/llvmjit_expr.c
index f9c7f29e728..db9f4928619 100644
--- a/src/backend/jit/llvm/llvmjit_expr.c
+++ b/src/backend/jit/llvm/llvmjit_expr.c
@@ -2256,6 +2256,32 @@ llvm_compile_expr(ExprState *state)
 				LLVMBuildBr(b, opblocks[opno + 1]);
 				break;
 
+			case EEOP_SAFETYPE_CAST:
+				{
+					SafeTypeCastState *stcstate = op->d.stcexpr.stcstate;
+
+					if (SOFT_ERROR_OCCURRED(&stcstate->escontext))
+					{
+						/*
+						 * Reset for next use such as for catching errors when
+						 * coercing a expression.
+						 */
+						stcstate->escontext.error_occurred = false;
+						stcstate->escontext.details_wanted = false;
+
+						/* set resnull to true */
+						LLVMBuildStore(b, l_sbool_const(1), v_resnullp);
+						/* reset resvalue */
+						LLVMBuildStore(b, l_datum_const(0), v_resvaluep);
+
+						LLVMBuildBr(b, opblocks[opno + 1]);
+					}
+					else
+						LLVMBuildBr(b, opblocks[stcstate->jump_end]);
+
+					break;
+				}
+
 			case EEOP_JSONEXPR_PATH:
 				{
 					JsonExprState *jsestate = op->d.jsonexpr.jsestate;
diff --git a/src/backend/nodes/nodeFuncs.c b/src/backend/nodes/nodeFuncs.c
index 024a2b2fd84..8a8d15ca6f5 100644
--- a/src/backend/nodes/nodeFuncs.c
+++ b/src/backend/nodes/nodeFuncs.c
@@ -206,6 +206,9 @@ exprType(const Node *expr)
 		case T_RowCompareExpr:
 			type = BOOLOID;
 			break;
+		case T_SafeTypeCastExpr:
+			type = ((const SafeTypeCastExpr *) expr)->resulttype;
+			break;
 		case T_CoalesceExpr:
 			type = ((const CoalesceExpr *) expr)->coalescetype;
 			break;
@@ -450,6 +453,8 @@ exprTypmod(const Node *expr)
 				return typmod;
 			}
 			break;
+		case T_SafeTypeCastExpr:
+			return ((const SafeTypeCastExpr *) expr)->resulttypmod;
 		case T_CoalesceExpr:
 			{
 				/*
@@ -965,6 +970,9 @@ exprCollation(const Node *expr)
 			/* RowCompareExpr's result is boolean ... */
 			coll = InvalidOid;	/* ... so it has no collation */
 			break;
+		case T_SafeTypeCastExpr:
+			coll = ((const SafeTypeCastExpr *) expr)->resultcollid;
+			break;
 		case T_CoalesceExpr:
 			coll = ((const CoalesceExpr *) expr)->coalescecollid;
 			break;
@@ -1232,6 +1240,9 @@ exprSetCollation(Node *expr, Oid collation)
 			/* RowCompareExpr's result is boolean ... */
 			Assert(!OidIsValid(collation)); /* ... so never set a collation */
 			break;
+		case T_SafeTypeCastExpr:
+			((SafeTypeCastExpr *) expr)->resultcollid = collation;
+			break;
 		case T_CoalesceExpr:
 			((CoalesceExpr *) expr)->coalescecollid = collation;
 			break;
@@ -1550,6 +1561,9 @@ exprLocation(const Node *expr)
 			/* just use leftmost argument's location */
 			loc = exprLocation((Node *) ((const RowCompareExpr *) expr)->largs);
 			break;
+		case T_SafeTypeCastExpr:
+			loc = ((const SafeTypeCastExpr *) expr)->location;
+			break;
 		case T_CoalesceExpr:
 			/* COALESCE keyword should always be the first thing */
 			loc = ((const CoalesceExpr *) expr)->location;
@@ -2321,6 +2335,18 @@ expression_tree_walker_impl(Node *node,
 					return true;
 			}
 			break;
+		case T_SafeTypeCastExpr:
+			{
+				SafeTypeCastExpr   *scexpr = (SafeTypeCastExpr *) node;
+
+				if (WALK(scexpr->source_expr))
+					return true;
+				if (WALK(scexpr->cast_expr))
+					return true;
+				if (WALK(scexpr->default_expr))
+					return true;
+			}
+			break;
 		case T_CoalesceExpr:
 			return WALK(((CoalesceExpr *) node)->args);
 		case T_MinMaxExpr:
@@ -3330,6 +3356,19 @@ expression_tree_mutator_impl(Node *node,
 				return (Node *) newnode;
 			}
 			break;
+		case T_SafeTypeCastExpr:
+			{
+				SafeTypeCastExpr   *scexpr = (SafeTypeCastExpr *) node;
+				SafeTypeCastExpr   *newnode;
+
+				FLATCOPY(newnode, scexpr, SafeTypeCastExpr);
+				MUTATE(newnode->source_expr, scexpr->source_expr, Node *);
+				MUTATE(newnode->cast_expr, scexpr->cast_expr, Node *);
+				MUTATE(newnode->default_expr, scexpr->default_expr, Node *);
+
+				return (Node *) newnode;
+			}
+			break;
 		case T_CoalesceExpr:
 			{
 				CoalesceExpr *coalesceexpr = (CoalesceExpr *) node;
@@ -4464,6 +4503,28 @@ raw_expression_tree_walker_impl(Node *node,
 					return true;
 			}
 			break;
+		case T_SafeTypeCast:
+			{
+				SafeTypeCast   *sc = (SafeTypeCast *) node;
+
+				if (WALK(sc->cast))
+					return true;
+				if (WALK(sc->raw_default))
+					return true;
+			}
+			break;
+		case T_SafeTypeCastExpr:
+			{
+				SafeTypeCastExpr   *stc = (SafeTypeCastExpr *) node;
+
+				if (WALK(stc->source_expr))
+					return true;
+				if (WALK(stc->cast_expr))
+					return true;
+				if (WALK(stc->default_expr))
+					return true;
+			}
+			break;
 		case T_CollateClause:
 			return WALK(((CollateClause *) node)->arg);
 		case T_SortBy:
diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c
index ddafc21c819..54046b12587 100644
--- a/src/backend/optimizer/util/clauses.c
+++ b/src/backend/optimizer/util/clauses.c
@@ -2447,7 +2447,8 @@ estimate_expression_value(PlannerInfo *root, Node *node)
 	((Node *) evaluate_expr((Expr *) (node), \
 							exprType((Node *) (node)), \
 							exprTypmod((Node *) (node)), \
-							exprCollation((Node *) (node))))
+							exprCollation((Node *) (node)), \
+							false))
 
 /*
  * Recursive guts of eval_const_expressions/estimate_expression_value
@@ -2958,6 +2959,32 @@ eval_const_expressions_mutator(Node *node,
 												  copyObject(jve->format));
 			}
 
+		case T_SafeTypeCastExpr:
+			{
+				SafeTypeCastExpr 	*stc = (SafeTypeCastExpr *) node;
+				SafeTypeCastExpr	*newexpr;
+				Node	   *source_expr = stc->source_expr;
+				Node	   *default_expr = stc->default_expr;
+
+				source_expr = eval_const_expressions_mutator(source_expr, context);
+				default_expr = eval_const_expressions_mutator(default_expr, context);
+
+				/*
+				 * We must not reduce any recognizably constant subexpressions
+				 * in cast_expr here, since we don’t want it to fail
+				 * prematurely.
+				 */
+				newexpr = makeNode(SafeTypeCastExpr);
+				newexpr->source_expr = source_expr;
+				newexpr->cast_expr = stc->cast_expr;
+				newexpr->default_expr = default_expr;
+				newexpr->resulttype = stc->resulttype;
+				newexpr->resulttypmod = stc->resulttypmod;
+				newexpr->resultcollid = stc->resultcollid;
+
+				return (Node *) newexpr;
+			}
+
 		case T_SubPlan:
 		case T_AlternativeSubPlan:
 
@@ -3380,7 +3407,8 @@ eval_const_expressions_mutator(Node *node,
 					return (Node *) evaluate_expr((Expr *) svf,
 												  svf->type,
 												  svf->typmod,
-												  InvalidOid);
+												  InvalidOid,
+												  false);
 				else
 					return copyObject((Node *) svf);
 			}
@@ -4698,7 +4726,7 @@ evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
 	newexpr->location = -1;
 
 	return evaluate_expr((Expr *) newexpr, result_type, result_typmod,
-						 result_collid);
+						 result_collid, false);
 }
 
 /*
@@ -5152,10 +5180,14 @@ sql_inline_error_callback(void *arg)
  *
  * We use the executor's routine ExecEvalExpr() to avoid duplication of
  * code and ensure we get the same result as the executor would get.
+ *
+ * When error_safe is set to true, we will evaluate the constant expression in a
+ * error safe way. If the evaluation fails, return NULL instead of throwing an
+ * error.
  */
 Expr *
 evaluate_expr(Expr *expr, Oid result_type, int32 result_typmod,
-			  Oid result_collation)
+			  Oid result_collation, bool error_safe)
 {
 	EState	   *estate;
 	ExprState  *exprstate;
@@ -5180,7 +5212,10 @@ evaluate_expr(Expr *expr, Oid result_type, int32 result_typmod,
 	 * Prepare expr for execution.  (Note: we can't use ExecPrepareExpr
 	 * because it'd result in recursively invoking eval_const_expressions.)
 	 */
-	exprstate = ExecInitExpr(expr, NULL);
+	if (error_safe)
+		exprstate = ExecInitExprSafe(expr, NULL);
+	else
+		exprstate = ExecInitExpr(expr, NULL);
 
 	/*
 	 * And evaluate it.
@@ -5200,6 +5235,12 @@ evaluate_expr(Expr *expr, Oid result_type, int32 result_typmod,
 	/* Get back to outer memory context */
 	MemoryContextSwitchTo(oldcontext);
 
+	if (error_safe && SOFT_ERROR_OCCURRED(exprstate->escontext))
+	{
+		FreeExecutorState(estate);
+		return NULL;
+	}
+
 	/*
 	 * Must copy result out of sub-context used by expression eval.
 	 *
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 7856ce9d78f..9e6573444cc 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -16013,6 +16013,28 @@ func_expr_common_subexpr:
 				}
 			| CAST '(' a_expr AS Typename ')'
 				{ $$ = makeTypeCast($3, $5, @1); }
+			| CAST '(' a_expr AS Typename ERROR_P ON CONVERSION_P ERROR_P ')'
+				{ $$ = makeTypeCast($3, $5, @1); }
+			| CAST '(' a_expr AS Typename NULL_P ON CONVERSION_P ERROR_P ')'
+				{
+					TypeCast *cast = (TypeCast *) makeTypeCast($3, $5, @1);
+
+					SafeTypeCast *safecast = makeNode(SafeTypeCast);
+					safecast->cast = (Node *) cast;
+					safecast->raw_default = makeNullAConst(-1);;
+
+					$$ = (Node *) safecast;
+				}
+			| CAST '(' a_expr AS Typename DEFAULT a_expr ON CONVERSION_P ERROR_P ')'
+				{
+					TypeCast *cast = (TypeCast *) makeTypeCast($3, $5, @1);
+
+					SafeTypeCast *safecast = makeNode(SafeTypeCast);
+					safecast->cast = (Node *) cast;
+					safecast->raw_default = $7;
+
+					$$ = (Node *) safecast;
+				}
 			| EXTRACT '(' extract_list ')'
 				{
 					$$ = (Node *) makeFuncCall(SystemFuncName("extract"),
diff --git a/src/backend/parser/parse_agg.c b/src/backend/parser/parse_agg.c
index b8340557b34..de77f6e9302 100644
--- a/src/backend/parser/parse_agg.c
+++ b/src/backend/parser/parse_agg.c
@@ -490,6 +490,12 @@ check_agglevels_and_constraints(ParseState *pstate, Node *expr)
 				err = _("grouping operations are not allowed in check constraints");
 
 			break;
+		case EXPR_KIND_CAST_DEFAULT:
+			if (isAgg)
+				err = _("aggregate functions are not allowed in CAST DEFAULT expressions");
+			else
+				err = _("grouping operations are not allowed in CAST DEFAULT expressions");
+			break;
 		case EXPR_KIND_COLUMN_DEFAULT:
 		case EXPR_KIND_FUNCTION_DEFAULT:
 
@@ -983,6 +989,9 @@ transformWindowFuncCall(ParseState *pstate, WindowFunc *wfunc,
 		case EXPR_KIND_DOMAIN_CHECK:
 			err = _("window functions are not allowed in check constraints");
 			break;
+		case EXPR_KIND_CAST_DEFAULT:
+			err = _("window functions are not allowed in CAST DEFAULT expressions");
+			break;
 		case EXPR_KIND_COLUMN_DEFAULT:
 		case EXPR_KIND_FUNCTION_DEFAULT:
 			err = _("window functions are not allowed in DEFAULT expressions");
diff --git a/src/backend/parser/parse_coerce.c b/src/backend/parser/parse_coerce.c
index 78b1e366ad7..4ae87e2030b 100644
--- a/src/backend/parser/parse_coerce.c
+++ b/src/backend/parser/parse_coerce.c
@@ -81,6 +81,31 @@ coerce_to_target_type(ParseState *pstate, Node *expr, Oid exprtype,
 					  CoercionContext ccontext,
 					  CoercionForm cformat,
 					  int location)
+{
+	return coerce_to_target_type_extended(pstate,
+										  expr,
+										  exprtype,
+										  targettype,
+										  targettypmod,
+										  ccontext,
+										  cformat,
+										  location,
+										  NULL);
+}
+
+/*
+ * escontext: If not NULL, expr (Unknown Const node type) will be coerced to the
+ * target type in an error-safe way. If it fails, NULL is returned.
+ *
+ * For other parameters, see above coerce_to_target_type.
+ */
+Node *
+coerce_to_target_type_extended(ParseState *pstate, Node *expr, Oid exprtype,
+							   Oid targettype, int32 targettypmod,
+							   CoercionContext ccontext,
+							   CoercionForm cformat,
+							   int location,
+							   Node *escontext)
 {
 	Node	   *result;
 	Node	   *origexpr;
@@ -102,9 +127,12 @@ coerce_to_target_type(ParseState *pstate, Node *expr, Oid exprtype,
 	while (expr && IsA(expr, CollateExpr))
 		expr = (Node *) ((CollateExpr *) expr)->arg;
 
-	result = coerce_type(pstate, expr, exprtype,
-						 targettype, targettypmod,
-						 ccontext, cformat, location);
+	result = coerce_type_extend(pstate, expr, exprtype,
+								targettype, targettypmod,
+								ccontext, cformat, location,
+								escontext);
+	if (SOFT_ERROR_OCCURRED(escontext))
+		return NULL;
 
 	/*
 	 * If the target is a fixed-length type, it may need a length coercion as
@@ -158,6 +186,18 @@ Node *
 coerce_type(ParseState *pstate, Node *node,
 			Oid inputTypeId, Oid targetTypeId, int32 targetTypeMod,
 			CoercionContext ccontext, CoercionForm cformat, int location)
+{
+	return coerce_type_extend(pstate, node,
+							  inputTypeId, targetTypeId, targetTypeMod,
+							  ccontext, cformat, location, NULL);
+}
+
+Node *
+coerce_type_extend(ParseState *pstate, Node *node,
+				   Oid inputTypeId, Oid targetTypeId, int32 targetTypeMod,
+				   CoercionContext ccontext, CoercionForm cformat,
+				   int location,
+				   Node *escontext)
 {
 	Node	   *result;
 	CoercionPathType pathtype;
@@ -256,6 +296,8 @@ coerce_type(ParseState *pstate, Node *node,
 		int32		inputTypeMod;
 		Type		baseType;
 		ParseCallbackState pcbstate;
+		char		*string;
+		bool		coercion_failed = false;
 
 		/*
 		 * If the target type is a domain, we want to call its base type's
@@ -308,21 +350,27 @@ coerce_type(ParseState *pstate, Node *node,
 		 * We assume here that UNKNOWN's internal representation is the same
 		 * as CSTRING.
 		 */
-		if (!con->constisnull)
-			newcon->constvalue = stringTypeDatum(baseType,
-												 DatumGetCString(con->constvalue),
-												 inputTypeMod);
+		if (con->constisnull)
+			string = NULL;
 		else
-			newcon->constvalue = stringTypeDatum(baseType,
-												 NULL,
-												 inputTypeMod);
+			string = DatumGetCString(con->constvalue);
+
+		if (!stringTypeDatumSafe(baseType,
+								 string,
+								 inputTypeMod,
+								 escontext,
+								 &newcon->constvalue))
+		{
+			coercion_failed = true;
+			newcon->constisnull = true;
+		}
 
 		/*
 		 * If it's a varlena value, force it to be in non-expanded
 		 * (non-toasted) format; this avoids any possible dependency on
 		 * external values and improves consistency of representation.
 		 */
-		if (!con->constisnull && newcon->constlen == -1)
+		if (!coercion_failed && !con->constisnull && newcon->constlen == -1)
 			newcon->constvalue =
 				PointerGetDatum(PG_DETOAST_DATUM(newcon->constvalue));
 
@@ -339,7 +387,7 @@ coerce_type(ParseState *pstate, Node *node,
 		 * identical may not get recognized as such.  See pgsql-hackers
 		 * discussion of 2008-04-04.
 		 */
-		if (!con->constisnull && !newcon->constbyval)
+		if (!coercion_failed && !con->constisnull && !newcon->constbyval)
 		{
 			Datum		val2;
 
@@ -358,8 +406,10 @@ coerce_type(ParseState *pstate, Node *node,
 
 		result = (Node *) newcon;
 
-		/* If target is a domain, apply constraints. */
-		if (baseTypeId != targetTypeId)
+		if (coercion_failed)
+			result = NULL;
+		else if (baseTypeId != targetTypeId)
+			/* If target is a domain, apply constraints. */
 			result = coerce_to_domain(result,
 									  baseTypeId, baseTypeMod,
 									  targetTypeId,
diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c
index 6b8fa15fca3..a10ec64a708 100644
--- a/src/backend/parser/parse_expr.c
+++ b/src/backend/parser/parse_expr.c
@@ -17,6 +17,7 @@
 
 #include "access/htup_details.h"
 #include "catalog/pg_aggregate.h"
+#include "catalog/pg_cast.h"
 #include "catalog/pg_type.h"
 #include "miscadmin.h"
 #include "nodes/makefuncs.h"
@@ -37,6 +38,7 @@
 #include "utils/date.h"
 #include "utils/fmgroids.h"
 #include "utils/lsyscache.h"
+#include "utils/syscache.h"
 #include "utils/timestamp.h"
 #include "utils/xml.h"
 
@@ -60,7 +62,8 @@ static Node *transformMultiAssignRef(ParseState *pstate, MultiAssignRef *maref);
 static Node *transformCaseExpr(ParseState *pstate, CaseExpr *c);
 static Node *transformSubLink(ParseState *pstate, SubLink *sublink);
 static Node *transformArrayExpr(ParseState *pstate, A_ArrayExpr *a,
-								Oid array_type, Oid element_type, int32 typmod);
+								Oid array_type, Oid element_type, int32 typmod,
+								bool *can_coerce);
 static Node *transformRowExpr(ParseState *pstate, RowExpr *r, bool allowDefault);
 static Node *transformCoalesceExpr(ParseState *pstate, CoalesceExpr *c);
 static Node *transformMinMaxExpr(ParseState *pstate, MinMaxExpr *m);
@@ -76,6 +79,10 @@ static Node *transformWholeRowRef(ParseState *pstate,
 								  int sublevels_up, int location);
 static Node *transformIndirection(ParseState *pstate, A_Indirection *ind);
 static Node *transformTypeCast(ParseState *pstate, TypeCast *tc);
+static Node *transformTypeSafeCast(ParseState *pstate, SafeTypeCast *tc);
+static void CoercionErrorSafeCheck(ParseState *pstate, Node *castexpr,
+								   Node *sourceexpr, Oid inputType,
+								   Oid targetType);
 static Node *transformCollateClause(ParseState *pstate, CollateClause *c);
 static Node *transformJsonObjectConstructor(ParseState *pstate,
 											JsonObjectConstructor *ctor);
@@ -164,13 +171,17 @@ transformExprRecurse(ParseState *pstate, Node *expr)
 
 		case T_A_ArrayExpr:
 			result = transformArrayExpr(pstate, (A_ArrayExpr *) expr,
-										InvalidOid, InvalidOid, -1);
+										InvalidOid, InvalidOid, -1, NULL);
 			break;
 
 		case T_TypeCast:
 			result = transformTypeCast(pstate, (TypeCast *) expr);
 			break;
 
+		case T_SafeTypeCast:
+			result = transformTypeSafeCast(pstate, (SafeTypeCast *) expr);
+			break;
+
 		case T_CollateClause:
 			result = transformCollateClause(pstate, (CollateClause *) expr);
 			break;
@@ -564,6 +575,7 @@ transformColumnRef(ParseState *pstate, ColumnRef *cref)
 		case EXPR_KIND_VALUES_SINGLE:
 		case EXPR_KIND_CHECK_CONSTRAINT:
 		case EXPR_KIND_DOMAIN_CHECK:
+		case EXPR_KIND_CAST_DEFAULT:
 		case EXPR_KIND_FUNCTION_DEFAULT:
 		case EXPR_KIND_INDEX_EXPRESSION:
 		case EXPR_KIND_INDEX_PREDICATE:
@@ -1824,6 +1836,9 @@ transformSubLink(ParseState *pstate, SubLink *sublink)
 		case EXPR_KIND_DOMAIN_CHECK:
 			err = _("cannot use subquery in check constraint");
 			break;
+		case EXPR_KIND_CAST_DEFAULT:
+			err = _("cannot use subquery in CAST DEFAULT expression");
+			break;
 		case EXPR_KIND_COLUMN_DEFAULT:
 		case EXPR_KIND_FUNCTION_DEFAULT:
 			err = _("cannot use subquery in DEFAULT expression");
@@ -2011,17 +2026,24 @@ transformSubLink(ParseState *pstate, SubLink *sublink)
  * If the caller specifies the target type, the resulting array will
  * be of exactly that type.  Otherwise we try to infer a common type
  * for the elements using select_common_type().
+ *
+ * Most of the time, can_coerce will be NULL.  It is not NULL only when
+ * performing parse analysis for CAST(DEFAULT ... ON CONVERSION ERROR)
+ * expression. It's default to true. If coercing array elements fails, it will
+ * be set to false.
  */
 static Node *
 transformArrayExpr(ParseState *pstate, A_ArrayExpr *a,
-				   Oid array_type, Oid element_type, int32 typmod)
+				   Oid array_type, Oid element_type, int32 typmod, bool *can_coerce)
 {
 	ArrayExpr  *newa = makeNode(ArrayExpr);
 	List	   *newelems = NIL;
 	List	   *newcoercedelems = NIL;
 	ListCell   *element;
 	Oid			coerce_type;
+	Oid			coerce_type_coll;
 	bool		coerce_hard;
+	ErrorSaveContext escontext = {T_ErrorSaveContext};
 
 	/*
 	 * Transform the element expressions
@@ -2045,9 +2067,10 @@ transformArrayExpr(ParseState *pstate, A_ArrayExpr *a,
 									  (A_ArrayExpr *) e,
 									  array_type,
 									  element_type,
-									  typmod);
+									  typmod,
+									  can_coerce);
 			/* we certainly have an array here */
-			Assert(array_type == InvalidOid || array_type == exprType(newe));
+			Assert(can_coerce || array_type == InvalidOid || array_type == exprType(newe));
 			newa->multidims = true;
 		}
 		else
@@ -2088,6 +2111,9 @@ transformArrayExpr(ParseState *pstate, A_ArrayExpr *a,
 	}
 	else
 	{
+		/* Target type must valid for CAST DEFAULT */
+		Assert(can_coerce == NULL);
+
 		/* Can't handle an empty array without a target type */
 		if (newelems == NIL)
 			ereport(ERROR,
@@ -2125,6 +2151,8 @@ transformArrayExpr(ParseState *pstate, A_ArrayExpr *a,
 		coerce_hard = false;
 	}
 
+	coerce_type_coll = get_typcollation(coerce_type);
+
 	/*
 	 * Coerce elements to target type
 	 *
@@ -2134,28 +2162,82 @@ transformArrayExpr(ParseState *pstate, A_ArrayExpr *a,
 	 * If the array's type was merely derived from the common type of its
 	 * elements, then the elements are implicitly coerced to the common type.
 	 * This is consistent with other uses of select_common_type().
+	 *
+	 * If can_coerce is not NULL, we need to safely test whether each element
+	 * can be coerced to the target type, similar to what is done in
+	 * transformTypeSafeCast.
 	 */
 	foreach(element, newelems)
 	{
 		Node	   *e = (Node *) lfirst(element);
-		Node	   *newe;
+		Node	   *newe = NULL;
 
 		if (coerce_hard)
 		{
-			newe = coerce_to_target_type(pstate, e,
-										 exprType(e),
-										 coerce_type,
-										 typmod,
-										 COERCION_EXPLICIT,
-										 COERCE_EXPLICIT_CAST,
-										 -1);
-			if (newe == NULL)
-				ereport(ERROR,
-						(errcode(ERRCODE_CANNOT_COERCE),
-						 errmsg("cannot cast type %s to %s",
-								format_type_be(exprType(e)),
-								format_type_be(coerce_type)),
-						 parser_errposition(pstate, exprLocation(e))));
+			/*
+			 * Can not coerce, just append the transformed element expression to
+			 * the list.
+			 */
+			if (can_coerce && (!*can_coerce))
+				newe = e;
+			else
+			{
+				Node	   *ecopy = NULL;
+
+				if (can_coerce)
+					ecopy = copyObject(e);
+
+				newe = coerce_to_target_type_extended(pstate, e,
+													  exprType(e),
+													  coerce_type,
+													  typmod,
+													  COERCION_EXPLICIT,
+													  COERCE_EXPLICIT_CAST,
+													  -1,
+													  (Node *) &escontext);
+				if (newe == NULL)
+				{
+					if (!can_coerce)
+						ereport(ERROR,
+								(errcode(ERRCODE_CANNOT_COERCE),
+								errmsg("cannot cast type %s to %s",
+									   format_type_be(exprType(e)),
+									   format_type_be(coerce_type)),
+								parser_errposition(pstate, exprLocation(e))));
+					else
+					{
+						/*
+						 * Can not coerce, just append the transformed element
+						 * expression to the list.
+						 */
+						newe = ecopy;
+						*can_coerce = false;
+					}
+				}
+				else if (can_coerce && IsA(ecopy, Const) && IsA(newe, FuncExpr))
+				{
+					Node	   *result;
+
+					/*
+					 * pre-evaluate simple constant cast expressions in a way
+					 * that tolerate errors.
+					 */
+					FuncExpr *newexpr = (FuncExpr *) copyObject(newe);
+
+					assign_expr_collations(pstate, (Node *) newexpr);
+
+					result = (Node *) evaluate_expr((Expr *) newexpr,
+													coerce_type,
+													typmod,
+													coerce_type_coll,
+													true);
+					if (result == NULL)
+					{
+						newe = ecopy;
+						*can_coerce = false;
+					}
+				}
+			}
 		}
 		else
 			newe = coerce_to_common_type(pstate, e,
@@ -2743,7 +2825,8 @@ transformTypeCast(ParseState *pstate, TypeCast *tc)
 									  (A_ArrayExpr *) arg,
 									  targetBaseType,
 									  elementType,
-									  targetBaseTypmod);
+									  targetBaseTypmod,
+									  NULL);
 		}
 		else
 			expr = transformExprRecurse(pstate, arg);
@@ -2780,6 +2863,291 @@ transformTypeCast(ParseState *pstate, TypeCast *tc)
 	return result;
 }
 
+/*
+ * Handle an explicit CAST(... DEFAULT ... ON CONVERSION ERROR) construct.
+ *
+ * Transform SafeTypeCast node, look up the type name, and apply any necessary
+ * coercion function(s).
+ */
+static Node *
+transformTypeSafeCast(ParseState *pstate, SafeTypeCast *tc)
+{
+	SafeTypeCastExpr   *result;
+	TypeCast   *tcast = (TypeCast *) tc->cast;
+	Node	   *source_expr;
+	Node	   *srcexpr;
+	Node	   *defexpr;
+	Node	   *cast_expr = NULL;
+	Oid			inputType;
+	Oid			targetType;
+	int32		targetTypmod;
+	Oid			targetTypecoll;
+	Oid			targetBaseType;
+	int32		targetBaseTypmod;
+	bool		can_coerce = true;
+
+	/* Look up the type name first */
+	typenameTypeIdAndMod(pstate, tcast->typeName, &targetType, &targetTypmod);
+	targetBaseTypmod = targetTypmod;
+
+	targetTypecoll = get_typcollation(targetType);
+
+	targetBaseType = getBaseTypeAndTypmod(targetType, &targetBaseTypmod);
+
+	/* now looking at DEFAULT expression */
+	defexpr = transformExpr(pstate, tc->raw_default, EXPR_KIND_CAST_DEFAULT);
+
+	defexpr = coerce_to_target_type(pstate, defexpr, exprType(defexpr),
+									targetType, targetTypmod,
+									COERCION_EXPLICIT,
+									COERCE_EXPLICIT_CAST,
+									exprLocation(defexpr));
+	if (defexpr == NULL)
+		ereport(ERROR,
+				errcode(ERRCODE_CANNOT_COERCE),
+				errmsg("cannot coerce %s expression to type %s",
+					   "CAST DEFAULT",
+					   format_type_be(targetType)),
+				parser_coercion_errposition(pstate, exprLocation(tc->raw_default), defexpr));
+
+	assign_expr_collations(pstate, defexpr);
+
+	/*
+	 * The collation of DEFAULT expression must match the collation of the
+	 * target type.
+	 */
+	if (OidIsValid(targetTypecoll))
+	{
+		Oid		defColl = exprCollation(defexpr);
+
+		if (OidIsValid(defColl) && targetTypecoll != defColl)
+			ereport(ERROR,
+					errcode(ERRCODE_DATATYPE_MISMATCH),
+					errmsg("the collation of CAST DEFAULT expression conflicts with target type collation"),
+					errdetail("\"%s\" versus \"%s\"",
+							  get_collation_name(targetTypecoll),
+							  get_collation_name(defColl)),
+					parser_errposition(pstate, exprLocation(defexpr)));
+	}
+
+	/*
+	 * If the type cast target type is an array type, we invoke
+	 * transformArrayExpr() directly so that we can pass down the type
+	 * information.  This avoids some cases where transformArrayExpr() might not
+	 * infer the correct type.  Otherwise, just transform the argument normally.
+	 */
+	if (IsA(tcast->arg, A_ArrayExpr))
+	{
+		Oid			elementType;
+
+		/*
+		 * If target is a domain over array, work with the base array type
+		 * here.  Below, we'll cast the array type to the domain.  In the
+		 * usual case that the target is not a domain, the remaining steps
+		 * will be a no-op.
+		 */
+		elementType = get_element_type(targetBaseType);
+
+		if (OidIsValid(elementType))
+		{
+			source_expr = transformArrayExpr(pstate,
+											 (A_ArrayExpr *) tcast->arg,
+											 targetBaseType,
+											 elementType,
+											 targetBaseTypmod,
+											 &can_coerce);
+		}
+		else
+			source_expr = transformExprRecurse(pstate, tcast->arg);
+	}
+	else
+		source_expr = transformExprRecurse(pstate, tcast->arg);
+
+	/*
+	 * Since we can't be certain that coerce_to_target_type_extended won't
+	 * modify the source expression, we create a copy of it first. This ensures
+	 * the transformed source expression is correctly passed to SafeTypeCastExpr
+	 */
+	srcexpr = copyObject(source_expr);
+
+	inputType = exprType(source_expr);
+	if (inputType == InvalidOid)
+		return (Node *) NULL;			/* return NULL if NULL input */
+
+	if (can_coerce)
+	{
+		ErrorSaveContext escontext = {T_ErrorSaveContext};
+
+		cast_expr = coerce_to_target_type_extended(pstate, source_expr, inputType,
+												   targetType, targetTypmod,
+												   COERCION_EXPLICIT,
+												   COERCE_EXPLICIT_CAST,
+												   tcast->location,
+												   (Node *) &escontext);
+		if (cast_expr == NULL)
+			can_coerce = false;
+
+		CoercionErrorSafeCheck(pstate, cast_expr, source_expr, inputType,
+							   targetType);
+	}
+
+	if (IsA(srcexpr, Const) && cast_expr && IsA(cast_expr, FuncExpr))
+	{
+		Node	   *result;
+
+		/*
+		 * pre-evaluate simple constant cast expressions in a error safe way
+		 *
+		 * Rationale:
+		 * 1. When deparsing safe cast expressions (or in other cases),
+		 *    eval_const_expressions might be invoked, but it cannot
+		 *    handle errors gracefully.
+		 * 2. If the cast expression involves only simple constants, we
+		 *    can safely evaluate it ahead of time. If the evaluation
+		 *    fails, it indicates that such a cast is not possible, and
+		 *    we can then fall back to the CAST DEFAULT expression.
+		 * 3. Even if FuncExpr (for castfunc) node has three arguments,
+		 *    the second and third arguments will also be constants per
+		 *    coerce_to_target_type. Evaluating a FuncExpr whose
+		 *    arguments are all Const is safe.
+		 */
+		FuncExpr *newexpr = (FuncExpr *) copyObject(cast_expr);
+
+		assign_expr_collations(pstate, (Node *) newexpr);
+
+		result = (Node *) evaluate_expr((Expr *) newexpr,
+										targetType,
+										targetTypmod,
+										targetTypecoll,
+										true);
+		if (result == NULL)
+		{
+			/* can not coerce, set can_coerce to false */
+			can_coerce = false;
+			cast_expr = NULL;
+		}
+	}
+
+	Assert(can_coerce || cast_expr == NULL);
+
+	result = makeNode(SafeTypeCastExpr);
+	result->source_expr = srcexpr;
+	result->cast_expr = cast_expr;
+	result->default_expr = defexpr;
+	result->resulttype = targetType;
+	result->resulttypmod = targetTypmod;
+	result->resultcollid = targetTypecoll;
+	result->location = tcast->location;
+
+	return (Node *) result;
+}
+
+/*
+ * Check coercion is error safe or not.  If not then report error
+ */
+static void
+CoercionErrorSafeCheck(ParseState *pstate, Node *castexpr, Node *sourceexpr, Oid inputType,
+					   Oid targetType)
+{
+	HeapTuple	tuple;
+	bool 	errorsafe = true;
+	bool	userdefined = false;
+	Oid		inputBaseType;
+	Oid		targetBaseType;
+	Oid 	inputElementType;
+	Oid		inputElementBaseType;
+	Oid 	targetElementType;
+	Oid		targetElementBaseType;
+
+	/*
+	 * Binary coercion cast is equivalent to no cast at all.  CoerceViaIO can
+	 * also be evaluated in an error-safe manner. So skip these two cases.
+	 */
+	if (!castexpr || IsA(castexpr, RelabelType) ||
+		IsA(castexpr, CoerceViaIO))
+		return;
+
+	/*
+	 * Type cast involving with some types is not error safe, do the check now.
+	 * We need consider domain over array and array over domain scarenio. We
+	 * already checked user-defined type cast above.
+	 */
+	inputElementType = get_element_type(inputType);
+
+	if (OidIsValid(inputElementType))
+		inputElementBaseType = getBaseType(inputElementType);
+	else
+	{
+		inputBaseType = getBaseType(inputType);
+
+		inputElementBaseType = get_element_type(inputBaseType);
+		if (!OidIsValid(inputElementBaseType))
+			inputElementBaseType = inputBaseType;
+	}
+
+	targetElementType = get_element_type(targetType);
+
+	if (OidIsValid(targetElementType))
+		targetElementBaseType = getBaseType(targetElementType);
+	else
+	{
+		targetBaseType = getBaseType(targetType);
+
+		targetElementBaseType = get_element_type(targetBaseType);
+		if (!OidIsValid(targetElementBaseType))
+			targetElementBaseType = targetBaseType;
+	}
+
+	if (inputElementBaseType == MONEYOID ||
+		targetElementBaseType == MONEYOID ||
+		(inputElementBaseType == CIRCLEOID &&
+		targetElementBaseType == POLYGONOID))
+	{
+		/*
+		 * Casts involving MONEY type are not error safe. The CIRCLE to POLYGON
+		 * cast is also unsafe because it relies on a SQL-language function;
+		 * only C-language functions are currently supported for error safe
+		 * casts.
+		 */
+		errorsafe = false;
+	}
+
+	if (errorsafe)
+	{
+		/* Look in pg_cast */
+		tuple = SearchSysCache2(CASTSOURCETARGET,
+								ObjectIdGetDatum(inputElementBaseType),
+								ObjectIdGetDatum(targetElementBaseType));
+
+		if (HeapTupleIsValid(tuple))
+		{
+			Form_pg_cast castForm = (Form_pg_cast) GETSTRUCT(tuple);
+
+			if (castForm->oid > FirstUnpinnedObjectId)
+			{
+				errorsafe = false;
+				userdefined = true;
+			}
+
+			ReleaseSysCache(tuple);
+		}
+	}
+
+	if (!errorsafe)
+		ereport(ERROR,
+				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				errmsg("cannot cast type %s to %s when %s expression is specified in %s",
+					   format_type_be(inputType),
+					   format_type_be(targetType),
+					   "DEFAULT",
+					   "CAST ... ON CONVERSION ERROR"),
+				userdefined
+				? errhint("Safe type cast for user-defined types are not yet supported")
+				: errhint("Explicit cast is defined but definition is not error safe"),
+				parser_errposition(pstate, exprLocation(sourceexpr)));
+}
+
+
 /*
  * Handle an explicit COLLATE clause.
  *
@@ -3193,6 +3561,8 @@ ParseExprKindName(ParseExprKind exprKind)
 		case EXPR_KIND_CHECK_CONSTRAINT:
 		case EXPR_KIND_DOMAIN_CHECK:
 			return "CHECK";
+		case EXPR_KIND_CAST_DEFAULT:
+			return "CAST DEFAULT";
 		case EXPR_KIND_COLUMN_DEFAULT:
 		case EXPR_KIND_FUNCTION_DEFAULT:
 			return "DEFAULT";
diff --git a/src/backend/parser/parse_func.c b/src/backend/parser/parse_func.c
index 778d69c6f3c..a90705b9847 100644
--- a/src/backend/parser/parse_func.c
+++ b/src/backend/parser/parse_func.c
@@ -2743,6 +2743,9 @@ check_srf_call_placement(ParseState *pstate, Node *last_srf, int location)
 		case EXPR_KIND_DOMAIN_CHECK:
 			err = _("set-returning functions are not allowed in check constraints");
 			break;
+		case EXPR_KIND_CAST_DEFAULT:
+			err = _("set-returning functions are not allowed in CAST DEFAULT expressions");
+			break;
 		case EXPR_KIND_COLUMN_DEFAULT:
 		case EXPR_KIND_FUNCTION_DEFAULT:
 			err = _("set-returning functions are not allowed in DEFAULT expressions");
diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c
index 905c975d83b..dc03cf4ce74 100644
--- a/src/backend/parser/parse_target.c
+++ b/src/backend/parser/parse_target.c
@@ -1822,6 +1822,20 @@ FigureColnameInternal(Node *node, char **name)
 				}
 			}
 			break;
+		case T_SafeTypeCast:
+			strength = FigureColnameInternal(((SafeTypeCast *) node)->cast,
+											 name);
+			if (strength <= 1)
+			{
+				TypeCast 	*node_cast;
+				node_cast = (TypeCast *)((SafeTypeCast *) node)->cast;
+				if (node_cast->typeName != NULL)
+				{
+					*name = strVal(llast(node_cast->typeName->names));
+					return 1;
+				}
+			}
+			break;
 		case T_CollateClause:
 			return FigureColnameInternal(((CollateClause *) node)->arg, name);
 		case T_GroupingFunc:
diff --git a/src/backend/parser/parse_type.c b/src/backend/parser/parse_type.c
index 9d7aa6967da..f6825bb9870 100644
--- a/src/backend/parser/parse_type.c
+++ b/src/backend/parser/parse_type.c
@@ -19,6 +19,7 @@
 #include "catalog/pg_type.h"
 #include "lib/stringinfo.h"
 #include "nodes/makefuncs.h"
+#include "nodes/miscnodes.h"
 #include "parser/parse_type.h"
 #include "parser/parser.h"
 #include "utils/array.h"
@@ -660,6 +661,19 @@ stringTypeDatum(Type tp, char *string, int32 atttypmod)
 	return OidInputFunctionCall(typinput, string, typioparam, atttypmod);
 }
 
+/* error-safe version of stringTypeDatum */
+bool
+stringTypeDatumSafe(Type tp, char *string, int32 atttypmod,
+					Node *escontext, Datum *result)
+{
+	Form_pg_type typform = (Form_pg_type) GETSTRUCT(tp);
+	Oid			typinput = typform->typinput;
+	Oid			typioparam = getTypeIOParam(tp);
+
+	return OidInputFunctionCallSafe(typinput, string, typioparam, atttypmod,
+									escontext, result);
+}
+
 /*
  * Given a typeid, return the type's typrelid (associated relation), if any.
  * Returns InvalidOid if type is not a composite type.
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index e96b38a59d5..6df0b975a88 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -4630,7 +4630,7 @@ transformPartitionBoundValue(ParseState *pstate, Node *val,
 		assign_expr_collations(pstate, value);
 		value = (Node *) expression_planner((Expr *) value);
 		value = (Node *) evaluate_expr((Expr *) value, colType, colTypmod,
-									   partCollation);
+									   partCollation, false);
 		if (!IsA(value, Const))
 			elog(ERROR, "could not evaluate partition bound expression");
 	}
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index b67ce57656a..c1027c5157d 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -3289,6 +3289,14 @@ array_map(Datum arrayd,
 		/* Apply the given expression to source element */
 		values[i] = ExecEvalExpr(exprstate, econtext, &nulls[i]);
 
+		/* Exit early if the evaluation fails */
+		if (SOFT_ERROR_OCCURRED(exprstate->escontext))
+		{
+			pfree(values);
+			pfree(nulls);
+			return (Datum) 0;
+		}
+
 		if (nulls[i])
 			hasnulls = true;
 		else
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 9f85eb86da1..17049f05cfc 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -10562,6 +10562,27 @@ get_rule_expr(Node *node, deparse_context *context,
 			}
 			break;
 
+		case T_SafeTypeCastExpr:
+			{
+				SafeTypeCastExpr   *stcexpr = castNode(SafeTypeCastExpr, node);
+
+				/*
+				 * Here, we cannot deparsing cast_expr directly, since
+				 * transformTypeSafeCast may have folded it into a simple
+				 * constant or NULL. Instead, we use source_expr and
+				 * default_expr to reconstruct the CAST DEFAULT clause.
+				 */
+				appendStringInfoString(buf, "CAST(");
+				get_rule_expr(stcexpr->source_expr, context, showimplicit);
+
+				appendStringInfo(buf, " AS %s ",
+								 format_type_with_typemod(stcexpr->resulttype,
+														  stcexpr->resulttypmod));
+				appendStringInfoString(buf, "DEFAULT ");
+				get_rule_expr(stcexpr->default_expr, context, showimplicit);
+				appendStringInfoString(buf, " ON CONVERSION ERROR)");
+			}
+			break;
 		case T_JsonExpr:
 			{
 				JsonExpr   *jexpr = (JsonExpr *) node;
diff --git a/src/backend/utils/fmgr/fmgr.c b/src/backend/utils/fmgr/fmgr.c
index 0fe63c6bb83..c9e5d0de8ed 100644
--- a/src/backend/utils/fmgr/fmgr.c
+++ b/src/backend/utils/fmgr/fmgr.c
@@ -1759,6 +1759,20 @@ OidInputFunctionCall(Oid functionId, char *str, Oid typioparam, int32 typmod)
 	return InputFunctionCall(&flinfo, str, typioparam, typmod);
 }
 
+/* error-safe version of OidInputFunctionCall */
+bool
+OidInputFunctionCallSafe(Oid functionId, char *str, Oid typioparam,
+						 int32 typmod, Node *escontext,
+						 Datum *result)
+{
+	FmgrInfo			flinfo;
+
+	fmgr_info(functionId, &flinfo);
+
+	return InputFunctionCallSafe(&flinfo, str, typioparam, typmod,
+								 escontext, result);
+}
+
 char *
 OidOutputFunctionCall(Oid functionId, Datum val)
 {
diff --git a/src/include/executor/execExpr.h b/src/include/executor/execExpr.h
index 75366203706..937cbf3bc9b 100644
--- a/src/include/executor/execExpr.h
+++ b/src/include/executor/execExpr.h
@@ -265,6 +265,7 @@ typedef enum ExprEvalOp
 	EEOP_XMLEXPR,
 	EEOP_JSON_CONSTRUCTOR,
 	EEOP_IS_JSON,
+	EEOP_SAFETYPE_CAST,
 	EEOP_JSONEXPR_PATH,
 	EEOP_JSONEXPR_COERCION,
 	EEOP_JSONEXPR_COERCION_FINISH,
@@ -750,6 +751,12 @@ typedef struct ExprEvalStep
 			JsonIsPredicate *pred;	/* original expression node */
 		}			is_json;
 
+		/* for EEOP_SAFETYPE_CAST */
+		struct
+		{
+			struct SafeTypeCastState *stcstate;
+		}			stcexpr;
+
 		/* for EEOP_JSONEXPR_PATH */
 		struct
 		{
diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h
index 7cd6a49309f..3e8ba551e73 100644
--- a/src/include/executor/executor.h
+++ b/src/include/executor/executor.h
@@ -324,6 +324,7 @@ ExecProcNode(PlanState *node)
  * prototypes from functions in execExpr.c
  */
 extern ExprState *ExecInitExpr(Expr *node, PlanState *parent);
+extern ExprState *ExecInitExprSafe(Expr *node, PlanState *parent);
 extern ExprState *ExecInitExprWithParams(Expr *node, ParamListInfo ext_params);
 extern ExprState *ExecInitQual(List *qual, PlanState *parent);
 extern ExprState *ExecInitCheck(List *qual, PlanState *parent);
diff --git a/src/include/fmgr.h b/src/include/fmgr.h
index c0dbe85ed1c..a9357b98d70 100644
--- a/src/include/fmgr.h
+++ b/src/include/fmgr.h
@@ -750,6 +750,9 @@ extern bool DirectInputFunctionCallSafe(PGFunction func, char *str,
 										Datum *result);
 extern Datum OidInputFunctionCall(Oid functionId, char *str,
 								  Oid typioparam, int32 typmod);
+extern bool OidInputFunctionCallSafe(Oid functionId, char *str, Oid typioparam,
+									 int32 typmod, Node *escontext,
+									 Datum *result);
 extern char *OutputFunctionCall(FmgrInfo *flinfo, Datum val);
 extern char *OidOutputFunctionCall(Oid functionId, Datum val);
 extern Datum ReceiveFunctionCall(FmgrInfo *flinfo, StringInfo buf,
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index 64ff6996431..9018e190cc7 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -1059,6 +1059,27 @@ typedef struct DomainConstraintState
 	ExprState  *check_exprstate;	/* check_expr's eval state, or NULL */
 } DomainConstraintState;
 
+typedef struct SafeTypeCastState
+{
+	SafeTypeCastExpr *stcexpr;
+
+	/*
+	 * Address to jump to when skipping all the steps to evaulate the default
+	 * expression.
+	 */
+	int 		jump_end;
+
+	/*
+	 * For error-safe evaluation of coercions. A pointer to this is passed to
+	 * ExecInitExprRec() when initializing the coercion expressions, see
+	 * ExecInitSafeTypeCastExpr.
+	 *
+	 * Reset for each evaluation of EEOP_SAFETYPE_CAST.
+	 */
+	ErrorSaveContext escontext;
+
+} SafeTypeCastState;
+
 /*
  * State for JsonExpr evaluation, too big to inline.
  *
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index d14294a4ece..82b0fb83b4b 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -400,6 +400,17 @@ typedef struct TypeCast
 	ParseLoc	location;		/* token location, or -1 if unknown */
 } TypeCast;
 
+/*
+ * SafeTypeCast - a CAST(source_expr AS target_type) DEFAULT ON CONVERSION ERROR
+ * construct
+ */
+typedef struct SafeTypeCast
+{
+	NodeTag		type;
+	Node		*cast;			/* TypeCast expression */
+	Node	   	*raw_default;	/* untransformed DEFAULT expression */
+} SafeTypeCast;
+
 /*
  * CollateClause - a COLLATE expression
  */
diff --git a/src/include/nodes/primnodes.h b/src/include/nodes/primnodes.h
index 1b4436f2ff6..1401109fb3c 100644
--- a/src/include/nodes/primnodes.h
+++ b/src/include/nodes/primnodes.h
@@ -769,6 +769,42 @@ typedef enum CoercionForm
 	COERCE_SQL_SYNTAX,			/* display with SQL-mandated special syntax */
 } CoercionForm;
 
+/*
+ * SafeTypeCastExpr -
+ *		Transformed representation of
+ * 		CAST(expr AS typename DEFAULT expr2 ON ERROR)
+ * 		CAST(expr AS typename NULL ON ERROR)
+ */
+typedef struct SafeTypeCastExpr
+{
+	Expr		xpr;
+
+	/* transformed source expression */
+	Node	   *source_expr;
+
+	/*
+	 * The transformed cast expression; NULL if we can not cocerce source
+	 * expression to the target type
+	 */
+	Node	   *cast_expr 	pg_node_attr(query_jumble_ignore);
+
+	/* Fall back to the default expression if cast evaluation fails */
+	Node	   *default_expr;
+
+	/* cast result data type */
+	Oid			resulttype;
+
+	/* cast result data type typmod (usually -1) */
+	int32		resulttypmod;
+
+	/* cast result data type collation */
+	Oid			resultcollid;
+
+	/* Original SafeTypeCastExpr's location */
+	ParseLoc	location;
+
+} SafeTypeCastExpr;
+
 /*
  * FuncExpr - expression node for a function call
  *
diff --git a/src/include/optimizer/optimizer.h b/src/include/optimizer/optimizer.h
index 44ec5296a18..587e711596a 100644
--- a/src/include/optimizer/optimizer.h
+++ b/src/include/optimizer/optimizer.h
@@ -143,7 +143,7 @@ extern void convert_saop_to_hashed_saop(Node *node);
 extern Node *estimate_expression_value(PlannerInfo *root, Node *node);
 
 extern Expr *evaluate_expr(Expr *expr, Oid result_type, int32 result_typmod,
-						   Oid result_collation);
+						   Oid result_collation, bool error_safe);
 
 extern bool var_is_nonnullable(PlannerInfo *root, Var *var, bool use_rel_info);
 
diff --git a/src/include/parser/parse_coerce.h b/src/include/parser/parse_coerce.h
index 8d775c72c59..1eca1ce727d 100644
--- a/src/include/parser/parse_coerce.h
+++ b/src/include/parser/parse_coerce.h
@@ -43,11 +43,26 @@ extern Node *coerce_to_target_type(ParseState *pstate,
 								   CoercionContext ccontext,
 								   CoercionForm cformat,
 								   int location);
+extern Node *coerce_to_target_type_extended(ParseState *pstate,
+											Node *expr,
+											Oid exprtype,
+											Oid targettype,
+											int32 targettypmod,
+											CoercionContext ccontext,
+											CoercionForm cformat,
+											int location,
+											Node *escontext);
 extern bool can_coerce_type(int nargs, const Oid *input_typeids, const Oid *target_typeids,
 							CoercionContext ccontext);
 extern Node *coerce_type(ParseState *pstate, Node *node,
 						 Oid inputTypeId, Oid targetTypeId, int32 targetTypeMod,
 						 CoercionContext ccontext, CoercionForm cformat, int location);
+extern Node *coerce_type_extend(ParseState *pstate, Node *node,
+								Oid inputTypeId,
+								Oid targetTypeId, int32 targetTypeMod,
+								CoercionContext ccontext, CoercionForm cformat,
+								int location,
+								Node *escontext);
 extern Node *coerce_to_domain(Node *arg, Oid baseTypeId, int32 baseTypeMod,
 							  Oid typeId,
 							  CoercionContext ccontext, CoercionForm cformat, int location,
diff --git a/src/include/parser/parse_node.h b/src/include/parser/parse_node.h
index f7d07c84542..9f5b32e0360 100644
--- a/src/include/parser/parse_node.h
+++ b/src/include/parser/parse_node.h
@@ -67,6 +67,8 @@ typedef enum ParseExprKind
 	EXPR_KIND_VALUES_SINGLE,	/* single-row VALUES (in INSERT only) */
 	EXPR_KIND_CHECK_CONSTRAINT, /* CHECK constraint for a table */
 	EXPR_KIND_DOMAIN_CHECK,		/* CHECK constraint for a domain */
+	EXPR_KIND_CAST_DEFAULT,		/* default expression in
+								   CAST DEFAULT ON CONVERSION ERROR */
 	EXPR_KIND_COLUMN_DEFAULT,	/* default value for a table column */
 	EXPR_KIND_FUNCTION_DEFAULT, /* default parameter value for function */
 	EXPR_KIND_INDEX_EXPRESSION, /* index expression */
diff --git a/src/include/parser/parse_type.h b/src/include/parser/parse_type.h
index 0d919d8bfa2..40aca2b31c9 100644
--- a/src/include/parser/parse_type.h
+++ b/src/include/parser/parse_type.h
@@ -47,6 +47,8 @@ extern char *typeTypeName(Type t);
 extern Oid	typeTypeRelid(Type typ);
 extern Oid	typeTypeCollation(Type typ);
 extern Datum stringTypeDatum(Type tp, char *string, int32 atttypmod);
+extern bool stringTypeDatumSafe(Type tp, char *string, int32 atttypmod,
+								Node *escontext, Datum *result);
 
 extern Oid	typeidTypeRelid(Oid type_id);
 extern Oid	typeOrDomainTypeRelid(Oid type_id);
diff --git a/src/test/regress/expected/cast.out b/src/test/regress/expected/cast.out
new file mode 100644
index 00000000000..b0dc7b8faea
--- /dev/null
+++ b/src/test/regress/expected/cast.out
@@ -0,0 +1,810 @@
+SET extra_float_digits = 0;
+-- CAST DEFAULT ON CONVERSION ERROR
+SELECT CAST(B'01' AS date DEFAULT NULL ON CONVERSION ERROR);
+ date 
+------
+ 
+(1 row)
+
+SELECT CAST(BIT'01' AS date DEFAULT NULL ON CONVERSION ERROR);
+ date 
+------
+ 
+(1 row)
+
+SELECT CAST(TRUE AS date DEFAULT NULL ON CONVERSION ERROR);
+ date 
+------
+ 
+(1 row)
+
+SELECT CAST(1.1 AS date DEFAULT NULL ON CONVERSION ERROR);
+ date 
+------
+ 
+(1 row)
+
+SELECT CAST(1 AS date DEFAULT NULL ON CONVERSION ERROR);
+ date 
+------
+ 
+(1 row)
+
+SELECT CAST(1111 AS "char" DEFAULT 'A' ON CONVERSION ERROR);
+ char 
+------
+ A
+(1 row)
+
+--test source expression is a unknown const
+VALUES (CAST('error' AS integer ERROR ON CONVERSION ERROR)); --error
+ERROR:  invalid input syntax for type integer: "error"
+LINE 1: VALUES (CAST('error' AS integer ERROR ON CONVERSION ERROR));
+                     ^
+VALUES (CAST('error' AS integer NULL ON CONVERSION ERROR));
+ column1 
+---------
+        
+(1 row)
+
+VALUES (CAST('error' AS integer DEFAULT 42 ON CONVERSION ERROR));
+ column1 
+---------
+      42
+(1 row)
+
+SELECT CAST('a' as int DEFAULT 18 ON CONVERSION ERROR);
+ int4 
+------
+   18
+(1 row)
+
+SELECT CAST('a' as int DEFAULT sum(1) ON CONVERSION ERROR); --error
+ERROR:  aggregate functions are not allowed in CAST DEFAULT expressions
+LINE 1: SELECT CAST('a' as int DEFAULT sum(1) ON CONVERSION ERROR);
+                                       ^
+SELECT CAST('a' as int DEFAULT sum(1) over() ON CONVERSION ERROR); --error
+ERROR:  window functions are not allowed in CAST DEFAULT expressions
+LINE 1: SELECT CAST('a' as int DEFAULT sum(1) over() ON CONVERSION E...
+                                       ^
+SELECT CAST('a' as int DEFAULT (SELECT NULL) ON CONVERSION ERROR); --error
+ERROR:  cannot use subquery in CAST DEFAULT expression
+LINE 1: SELECT CAST('a' as int DEFAULT (SELECT NULL) ON CONVERSION E...
+                                       ^
+SELECT CAST('a' as int DEFAULT 'b' ON CONVERSION ERROR); --error
+ERROR:  invalid input syntax for type integer: "b"
+LINE 1: SELECT CAST('a' as int DEFAULT 'b' ON CONVERSION ERROR);
+                                       ^
+SELECT CAST('a'::int as int DEFAULT NULL ON CONVERSION ERROR); --error
+ERROR:  invalid input syntax for type integer: "a"
+LINE 1: SELECT CAST('a'::int as int DEFAULT NULL ON CONVERSION ERROR...
+                    ^
+--the default expression’s collation should match the collation of the cast
+--target type
+VALUES (CAST('error' AS text DEFAULT '1' COLLATE "C" ON CONVERSION ERROR));
+ERROR:  the collation of CAST DEFAULT expression conflicts with target type collation
+LINE 1: VALUES (CAST('error' AS text DEFAULT '1' COLLATE "C" ON CONV...
+                                             ^
+DETAIL:  "default" versus "C"
+VALUES (CAST('error' AS int2vector DEFAULT '1 3'  ON CONVERSION ERROR));
+ column1 
+---------
+ 1 3
+(1 row)
+
+VALUES (CAST('error' AS int2vector[] DEFAULT '{1 3}'  ON CONVERSION ERROR));
+ column1 
+---------
+ {"1 3"}
+(1 row)
+
+-- test source expression contain subquery
+SELECT CAST((SELECT b FROM generate_series(1, 1), (VALUES('H')) s(b))
+            AS int2vector[] DEFAULT '{1 3}'  ON CONVERSION ERROR);
+    b    
+---------
+ {"1 3"}
+(1 row)
+
+SELECT CAST((SELECT ARRAY((SELECT b FROM generate_series(1, 2) g, (VALUES('H')) s(b))))
+            AS INT[]
+            DEFAULT NULL ON CONVERSION ERROR);
+ array 
+-------
+ 
+(1 row)
+
+CREATE FUNCTION ret_int8() RETURNS BIGINT AS
+$$
+BEGIN RETURN 2147483648; END;
+$$
+LANGUAGE plpgsql IMMUTABLE;
+SELECT CAST('a' as int DEFAULT ret_int8() ON CONVERSION ERROR); --error
+ERROR:  integer out of range
+SELECT CAST('a' as date DEFAULT ret_int8() ON CONVERSION ERROR); --error
+ERROR:  cannot coerce CAST DEFAULT expression to type date
+LINE 1: SELECT CAST('a' as date DEFAULT ret_int8() ON CONVERSION ERR...
+                                        ^
+-- DEFAULT expression can not be set-returning
+CREATE FUNCTION ret_setint() RETURNS SETOF integer AS
+$$
+BEGIN RETURN QUERY EXECUTE 'select 1 union all select 1'; END;
+$$
+LANGUAGE plpgsql IMMUTABLE;
+CREATE TABLE tcast(a text[], b int GENERATED BY DEFAULT AS IDENTITY);
+INSERT INTO tcast VALUES ('{12}'), ('{1,a, b}'), ('{{1,2}, {c,d}}'), ('{13}');
+SELECT CAST('a' as int DEFAULT ret_setint() ON CONVERSION ERROR) FROM tcast; --error
+ERROR:  set-returning functions are not allowed in CAST DEFAULT expressions
+LINE 1: SELECT CAST('a' as int DEFAULT ret_setint() ON CONVERSION ER...
+                                       ^
+SELECT CAST(t AS text[] DEFAULT '{21,22, ' || b || '}' ON CONVERSION ERROR) FROM tcast as t;
+     t     
+-----------
+ {21,22,1}
+ {21,22,2}
+ {21,22,3}
+ {21,22,4}
+(4 rows)
+
+SELECT CAST(t.a AS int[] DEFAULT '{21,22}'::int[] || b ON CONVERSION ERROR) FROM tcast as t;
+     a     
+-----------
+ {12}
+ {21,22,2}
+ {21,22,3}
+ {13}
+(4 rows)
+
+-- test with user-defined type, domain, array over domain, domain over array
+CREATE DOMAIN d_int42 as int check (value = 42) NOT NULL;
+CREATE DOMAIN d_char3_not_null as char(3) NOT NULL;
+CREATE DOMAIN d_varchar as varchar(3) NOT NULL;
+CREATE DOMAIN d_int_arr as int[] check (value = '{41, 43}') NOT NULL;
+CREATE TYPE comp_domain_with_typmod AS (a d_char3_not_null, b int);
+CREATE TYPE comp2 AS (a d_varchar);
+SELECT CAST('(NULL)' AS comp2 DEFAULT '(1232)' ON CONVERSION ERROR); --error
+ERROR:  value too long for type character varying(3)
+LINE 1: SELECT CAST('(NULL)' AS comp2 DEFAULT '(1232)' ON CONVERSION...
+                                              ^
+SELECT CAST('(NULL)' AS comp2 DEFAULT '(123)' ON CONVERSION ERROR);
+ comp2 
+-------
+ (123)
+(1 row)
+
+SELECT CAST(11 AS d_int42 DEFAULT 41 ON CONVERSION ERROR); --error
+ERROR:  value for domain d_int42 violates check constraint "d_int42_check"
+SELECT CAST(11 AS d_int42 DEFAULT 42 ON CONVERSION ERROR);
+ d_int42 
+---------
+      42
+(1 row)
+
+SELECT CAST(NULL AS d_int42 DEFAULT NULL ON CONVERSION ERROR); --error
+ERROR:  domain d_int42 does not allow null values
+SELECT CAST(NULL AS d_int42 DEFAULT 42 ON CONVERSION ERROR);
+ d_int42 
+---------
+      42
+(1 row)
+
+SELECT CAST('(,42)' AS comp_domain_with_typmod DEFAULT NULL ON CONVERSION ERROR);
+ comp_domain_with_typmod 
+-------------------------
+ 
+(1 row)
+
+SELECT CAST('(NULL,42)' AS comp_domain_with_typmod DEFAULT '(1,2)' ON CONVERSION ERROR);
+ comp_domain_with_typmod 
+-------------------------
+ ("1  ",2)
+(1 row)
+
+SELECT CAST('(NULL,42)' AS comp_domain_with_typmod DEFAULT '(1234,2)' ON CONVERSION ERROR); --error
+ERROR:  value too long for type character(3)
+LINE 1: ...ST('(NULL,42)' AS comp_domain_with_typmod DEFAULT '(1234,2)'...
+                                                             ^
+SELECT CAST(ARRAY[42,41] AS d_int42[] DEFAULT '{42, 42}' ON CONVERSION ERROR);
+  array  
+---------
+ {42,42}
+(1 row)
+
+SELECT CAST(ARRAY[42,41] AS d_int_arr DEFAULT '{41, 43}' ON CONVERSION ERROR);
+  array  
+---------
+ {41,43}
+(1 row)
+
+-- test array coerce
+SELECT CAST(array['a'::text] AS int[] DEFAULT NULL ON CONVERSION ERROR); --error
+ERROR:  invalid input syntax for type integer: "a"
+SELECT CAST(array['a'] AS int[] DEFAULT ARRAY[1] ON CONVERSION ERROR);
+ array 
+-------
+ {1}
+(1 row)
+
+SELECT CAST(array[11.12] AS date[] DEFAULT NULL ON CONVERSION ERROR);
+ array 
+-------
+ 
+(1 row)
+
+SELECT CAST(array[11111111111111111] AS int[] DEFAULT NULL ON CONVERSION ERROR);
+ array 
+-------
+ 
+(1 row)
+
+SELECT CAST(array[['abc'],[456]] AS int[] DEFAULT NULL ON CONVERSION ERROR);
+ array 
+-------
+ 
+(1 row)
+
+SELECT CAST('{123,abc,456}' AS int[] DEFAULT '{-789}' ON CONVERSION ERROR);
+  int4  
+--------
+ {-789}
+(1 row)
+
+SELECT CAST('{234,def,567}'::text[] AS integer[] DEFAULT '{-1011}' ON CONVERSION ERROR);
+  int4   
+---------
+ {-1011}
+(1 row)
+
+SELECT CAST(ARRAY[['1'], ['three'],['a']] AS int[] DEFAULT '{1,2}' ON CONVERSION ERROR);
+ array 
+-------
+ {1,2}
+(1 row)
+
+SELECT CAST(ARRAY[['1', '2'], ['three', 'a']] AS int[] DEFAULT '{21,22}' ON CONVERSION ERROR); --ok
+  array  
+---------
+ {21,22}
+(1 row)
+
+SELECT CAST(ARRAY[['1', '2'], ['three'::int, 'a']] AS int[] DEFAULT '{21,22}' ON CONVERSION ERROR); --error
+ERROR:  invalid input syntax for type integer: "three"
+LINE 1: SELECT CAST(ARRAY[['1', '2'], ['three'::int, 'a']] AS int[] ...
+                                       ^
+SELECT CAST(ARRAY[1, 'three'::int] AS int[] DEFAULT '{21,22}' ON CONVERSION ERROR); --error
+ERROR:  invalid input syntax for type integer: "three"
+LINE 1: SELECT CAST(ARRAY[1, 'three'::int] AS int[] DEFAULT '{21,22}...
+                             ^
+-----safe cast with geometry data type
+SELECT CAST('(1,2)'::point AS box DEFAULT NULL ON CONVERSION ERROR);
+     box     
+-------------
+ (1,2),(1,2)
+(1 row)
+
+SELECT CAST('[(NaN,1),(NaN,infinity)]'::lseg AS point DEFAULT NULL ON CONVERSION ERROR);
+     point      
+----------------
+ (NaN,Infinity)
+(1 row)
+
+SELECT CAST('[(1e+300,Infinity),(1e+300,Infinity)]'::lseg AS point DEFAULT NULL ON CONVERSION ERROR);
+       point       
+-------------------
+ (1e+300,Infinity)
+(1 row)
+
+SELECT CAST('[(1,2),(3,4)]'::path as polygon DEFAULT NULL ON CONVERSION ERROR);
+ polygon 
+---------
+ 
+(1 row)
+
+SELECT CAST('(NaN,1.0,NaN,infinity)'::box AS point DEFAULT NULL ON CONVERSION ERROR);
+     point      
+----------------
+ (NaN,Infinity)
+(1 row)
+
+SELECT CAST('(2.0,2.0,0.0,0.0)'::box AS lseg DEFAULT NULL ON CONVERSION ERROR);
+     lseg      
+---------------
+ [(2,2),(0,0)]
+(1 row)
+
+SELECT CAST('(2.0,2.0,0.0,0.0)'::box AS polygon DEFAULT NULL ON CONVERSION ERROR);
+          polygon          
+---------------------------
+ ((0,0),(0,2),(2,2),(2,0))
+(1 row)
+
+SELECT CAST('(2.0,2.0,0.0,0.0)'::box AS path DEFAULT NULL ON CONVERSION ERROR);
+ path 
+------
+ 
+(1 row)
+
+SELECT CAST('(2.0,infinity,NaN,infinity)'::box AS circle DEFAULT NULL ON CONVERSION ERROR);
+        circle        
+----------------------
+ <(NaN,Infinity),NaN>
+(1 row)
+
+SELECT CAST('(NaN,0.0),(2.0,4.0),(0.0,infinity)'::polygon AS point DEFAULT NULL ON CONVERSION ERROR);
+     point      
+----------------
+ (NaN,Infinity)
+(1 row)
+
+SELECT CAST('(2.0,0.0),(2.0,4.0),(0.0,0.0)'::polygon AS path DEFAULT NULL ON CONVERSION ERROR);
+        path         
+---------------------
+ ((2,0),(2,4),(0,0))
+(1 row)
+
+SELECT CAST('(2.0,0.0),(2.0,4.0),(0.0,0.0)'::polygon AS box DEFAULT NULL ON CONVERSION ERROR);
+     box     
+-------------
+ (2,4),(0,0)
+(1 row)
+
+SELECT CAST('(NaN,infinity),(2.0,4.0),(0.0,infinity)'::polygon AS circle DEFAULT NULL ON CONVERSION ERROR);
+        circle        
+----------------------
+ <(NaN,Infinity),NaN>
+(1 row)
+
+SELECT CAST('<(5,1),3>'::circle AS point DEFAULT NULL ON CONVERSION ERROR);
+ point 
+-------
+ (5,1)
+(1 row)
+
+SELECT CAST('<(3,5),0>'::circle as box DEFAULT NULL ON CONVERSION ERROR);
+     box     
+-------------
+ (3,5),(3,5)
+(1 row)
+
+-- not supported because the cast from circle to polygon is implemented as a SQL
+-- function, which cannot be error-safe.
+SELECT CAST('<(3,5),0>'::circle as polygon DEFAULT NULL ON CONVERSION ERROR);
+ERROR:  cannot cast type circle to polygon when DEFAULT expression is specified in CAST ... ON CONVERSION ERROR
+LINE 1: SELECT CAST('<(3,5),0>'::circle as polygon DEFAULT NULL ON C...
+                    ^
+HINT:  Explicit cast is defined but definition is not error safe
+-----safe cast from/to money type is not supported, all the following would result error
+SELECT CAST(NULL::int8 AS money DEFAULT NULL ON CONVERSION ERROR);
+ERROR:  cannot cast type bigint to money when DEFAULT expression is specified in CAST ... ON CONVERSION ERROR
+LINE 1: SELECT CAST(NULL::int8 AS money DEFAULT NULL ON CONVERSION E...
+                    ^
+HINT:  Explicit cast is defined but definition is not error safe
+SELECT CAST(NULL::int4 AS money DEFAULT NULL ON CONVERSION ERROR);
+ERROR:  cannot cast type integer to money when DEFAULT expression is specified in CAST ... ON CONVERSION ERROR
+LINE 1: SELECT CAST(NULL::int4 AS money DEFAULT NULL ON CONVERSION E...
+                    ^
+HINT:  Explicit cast is defined but definition is not error safe
+SELECT CAST(NULL::numeric AS money DEFAULT NULL ON CONVERSION ERROR);
+ERROR:  cannot cast type numeric to money when DEFAULT expression is specified in CAST ... ON CONVERSION ERROR
+LINE 1: SELECT CAST(NULL::numeric AS money DEFAULT NULL ON CONVERSIO...
+                    ^
+HINT:  Explicit cast is defined but definition is not error safe
+SELECT CAST(NULL::money AS numeric DEFAULT NULL ON CONVERSION ERROR);
+ERROR:  cannot cast type money to numeric when DEFAULT expression is specified in CAST ... ON CONVERSION ERROR
+LINE 1: SELECT CAST(NULL::money AS numeric DEFAULT NULL ON CONVERSIO...
+                    ^
+HINT:  Explicit cast is defined but definition is not error safe
+SELECT CAST(NULL::money[] AS numeric[] DEFAULT NULL ON CONVERSION ERROR);
+ERROR:  cannot cast type money[] to numeric[] when DEFAULT expression is specified in CAST ... ON CONVERSION ERROR
+LINE 1: SELECT CAST(NULL::money[] AS numeric[] DEFAULT NULL ON CONVE...
+                    ^
+HINT:  Explicit cast is defined but definition is not error safe
+-----safe cast from bytea type to other data types
+SELECT CAST ('\x112233445566778899'::bytea AS int8 DEFAULT 19 ON CONVERSION ERROR);
+ int8 
+------
+   19
+(1 row)
+
+SELECT CAST('\x123456789A'::bytea AS int4 DEFAULT 20 ON CONVERSION ERROR);
+ int4 
+------
+   20
+(1 row)
+
+SELECT CAST('\x123456'::bytea AS int2 DEFAULT 21 ON CONVERSION ERROR);
+ int2 
+------
+   21
+(1 row)
+
+-----safe cast from bit type to other data types
+SELECT CAST('111111111100001'::bit(100) AS INT DEFAULT 22 ON CONVERSION ERROR);
+ int4 
+------
+   22
+(1 row)
+
+SELECT CAST ('111111111100001'::bit(100) AS INT8 DEFAULT 23 ON CONVERSION ERROR);
+ int8 
+------
+   23
+(1 row)
+
+-----safe cast from text type to other data types
+select CAST('a.b.c.d'::text as regclass default NULL on conversion error);
+ regclass 
+----------
+ 
+(1 row)
+
+CREATE TABLE test_safecast(col0 text);
+INSERT INTO test_safecast(col0) VALUES ('<value>one</value');
+SELECT col0 as text,
+       CAST(col0 AS regclass DEFAULT NULL ON CONVERSION ERROR) as to_regclass,
+       CAST(col0 AS regclass DEFAULT NULL ON CONVERSION ERROR) IS NULL as expect_true,
+       CAST(col0 AS "char"  DEFAULT NULL ON CONVERSION ERROR) as to_char,
+       CAST(col0 AS name DEFAULT NULL ON CONVERSION ERROR) as to_name,
+       CAST(col0 AS xml DEFAULT NULL ON CONVERSION ERROR) as to_xml
+FROM test_safecast;
+       text        | to_regclass | expect_true | to_char |      to_name      | to_xml 
+-------------------+-------------+-------------+---------+-------------------+--------
+ <value>one</value |             | t           | <       | <value>one</value | 
+(1 row)
+
+SELECT CAST('192.168.1.x' as inet DEFAULT NULL ON CONVERSION ERROR);
+ inet 
+------
+ 
+(1 row)
+
+SELECT CAST('192.168.1.2/30' as cidr DEFAULT NULL ON CONVERSION ERROR);
+ cidr 
+------
+ 
+(1 row)
+
+SELECT CAST('22:00:5c:08:55:08:01:02'::macaddr8 as macaddr DEFAULT NULL ON CONVERSION ERROR);
+ macaddr 
+---------
+ 
+(1 row)
+
+-----safe cast betweeen range data types
+SELECT CAST('[1,2]'::int4range AS int4multirange DEFAULT NULL ON CONVERSION ERROR);
+ int4multirange 
+----------------
+ {[1,3)}
+(1 row)
+
+SELECT CAST('[1,2]'::int8range AS int8multirange DEFAULT NULL ON CONVERSION ERROR);
+ int8multirange 
+----------------
+ {[1,3)}
+(1 row)
+
+SELECT CAST('[1,2]'::numrange  AS nummultirange DEFAULT NULL ON CONVERSION ERROR);
+ nummultirange 
+---------------
+ {[1,2]}
+(1 row)
+
+SELECT CAST('[-infinity,infinity]'::daterange AS datemultirange DEFAULT NULL ON CONVERSION ERROR);
+     datemultirange     
+------------------------
+ {[-infinity,infinity]}
+(1 row)
+
+SELECT CAST('[-infinity,infinity]'::tsrange AS tsmultirange DEFAULT NULL ON CONVERSION ERROR);
+      tsmultirange      
+------------------------
+ {[-infinity,infinity]}
+(1 row)
+
+SELECT CAST('[-infinity,infinity]'::tstzrange AS tstzmultirange DEFAULT NULL ON CONVERSION ERROR);
+     tstzmultirange     
+------------------------
+ {[-infinity,infinity]}
+(1 row)
+
+-----safe cast betweeen numeric data types
+CREATE TABLE test_safecast1(
+  col1 float4, col2 float8, col3 numeric, col4 numeric[],
+  col5 int2 default 32767,
+  col6 int4 default 32768,
+  col7 int8 default 4294967296);
+INSERT INTO test_safecast1 VALUES('11.1234', '11.1234', '9223372036854775808', '{11.1234}'::numeric[]);
+INSERT INTO test_safecast1 VALUES('inf', 'inf', 'inf', '{11.1234, 12, inf, NaN}'::numeric[]);
+INSERT INTO test_safecast1 VALUES('-inf', '-inf', '-inf', '{11.1234, 12, -inf, NaN}'::numeric[]);
+INSERT INTO test_safecast1 VALUES('NaN', 'NaN', 'NaN', '{11.1234, 12, -inf, NaN}'::numeric[]);
+SELECT col5 as int2,
+       CAST(col5 AS int2 DEFAULT NULL ON CONVERSION ERROR) as to_int2,
+       CAST(col5 AS int4 DEFAULT NULL ON CONVERSION ERROR) as to_int4,
+       CAST(col5 AS oid DEFAULT NULL ON CONVERSION ERROR) as to_oid,
+       CAST(col5 as int8 DEFAULT NULL ON CONVERSION ERROR) as to_int8,
+       CAST(col5 as float4 DEFAULT NULL ON CONVERSION ERROR) as to_float4,
+       CAST(col5 as float8 DEFAULT NULL ON CONVERSION ERROR) as to_float8,
+       CAST(col5 as numeric DEFAULT NULL ON CONVERSION ERROR) as to_numeric,
+       CAST(col5 as numeric(10,1) DEFAULT NULL ON CONVERSION ERROR) as to_numeric_scale
+FROM test_safecast1;
+ int2  | to_int2 | to_int4 | to_oid | to_int8 | to_float4 | to_float8 | to_numeric | to_numeric_scale 
+-------+---------+---------+--------+---------+-----------+-----------+------------+------------------
+ 32767 |   32767 |   32767 |  32767 |   32767 |     32767 |     32767 |      32767 |          32767.0
+ 32767 |   32767 |   32767 |  32767 |   32767 |     32767 |     32767 |      32767 |          32767.0
+ 32767 |   32767 |   32767 |  32767 |   32767 |     32767 |     32767 |      32767 |          32767.0
+ 32767 |   32767 |   32767 |  32767 |   32767 |     32767 |     32767 |      32767 |          32767.0
+(4 rows)
+
+SELECT col6 as int4,
+       CAST(col6 AS int2 DEFAULT NULL ON CONVERSION ERROR) as to_int2,
+       CAST(col6 AS int4 DEFAULT NULL ON CONVERSION ERROR) as to_int4,
+       CAST(col6 AS oid DEFAULT NULL ON CONVERSION ERROR) as to_oid,
+       CAST(col6 as int8 DEFAULT NULL ON CONVERSION ERROR) as to_int8,
+       CAST(col6 as float4 DEFAULT NULL ON CONVERSION ERROR) as to_float4,
+       CAST(col6 as float8 DEFAULT NULL ON CONVERSION ERROR) as to_float8,
+       CAST(col6 as numeric DEFAULT NULL ON CONVERSION ERROR) as to_numeric,
+       CAST(col6 as numeric(10,1) DEFAULT NULL ON CONVERSION ERROR) as to_numeric_scale
+FROM test_safecast1;
+ int4  | to_int2 | to_int4 | to_oid | to_int8 | to_float4 | to_float8 | to_numeric | to_numeric_scale 
+-------+---------+---------+--------+---------+-----------+-----------+------------+------------------
+ 32768 |         |   32768 |  32768 |   32768 |     32768 |     32768 |      32768 |          32768.0
+ 32768 |         |   32768 |  32768 |   32768 |     32768 |     32768 |      32768 |          32768.0
+ 32768 |         |   32768 |  32768 |   32768 |     32768 |     32768 |      32768 |          32768.0
+ 32768 |         |   32768 |  32768 |   32768 |     32768 |     32768 |      32768 |          32768.0
+(4 rows)
+
+SELECT col7 as int8,
+       CAST(col7 AS int2 DEFAULT NULL ON CONVERSION ERROR) as to_int2,
+       CAST(col7 AS int4 DEFAULT NULL ON CONVERSION ERROR) as to_int4,
+       CAST(col7 AS oid DEFAULT NULL ON CONVERSION ERROR) as to_oid,
+       CAST(col7 as int8 DEFAULT NULL ON CONVERSION ERROR) as to_int8,
+       CAST(col7 as float4 DEFAULT NULL ON CONVERSION ERROR) as to_float4,
+       CAST(col7 as float8 DEFAULT NULL ON CONVERSION ERROR) as to_float8,
+       CAST(col7 as numeric DEFAULT NULL ON CONVERSION ERROR) as to_numeric,
+       CAST(col7 as numeric(10,1) DEFAULT NULL ON CONVERSION ERROR) as to_numeric_scale
+FROM test_safecast1;
+    int8    | to_int2 | to_int4 | to_oid |  to_int8   |  to_float4  | to_float8  | to_numeric | to_numeric_scale 
+------------+---------+---------+--------+------------+-------------+------------+------------+------------------
+ 4294967296 |         |         |        | 4294967296 | 4.29497e+09 | 4294967296 | 4294967296 |                 
+ 4294967296 |         |         |        | 4294967296 | 4.29497e+09 | 4294967296 | 4294967296 |                 
+ 4294967296 |         |         |        | 4294967296 | 4.29497e+09 | 4294967296 | 4294967296 |                 
+ 4294967296 |         |         |        | 4294967296 | 4.29497e+09 | 4294967296 | 4294967296 |                 
+(4 rows)
+
+SELECT col3 as numeric,
+       CAST(col3 AS int2 DEFAULT NULL ON CONVERSION ERROR) as to_int2,
+       CAST(col3 AS int4 DEFAULT NULL ON CONVERSION ERROR) as to_int4,
+       CAST(col3 AS oid DEFAULT NULL ON CONVERSION ERROR) as to_oid,
+       CAST(col3 as int8 DEFAULT NULL ON CONVERSION ERROR) as to_int8,
+       CAST(col3 as float4 DEFAULT NULL ON CONVERSION ERROR) as to_float4,
+       CAST(col3 as float8 DEFAULT NULL ON CONVERSION ERROR) as to_float8,
+       CAST(col3 as numeric DEFAULT NULL ON CONVERSION ERROR) as to_numeric,
+       CAST(col3 as numeric(10,1) DEFAULT NULL ON CONVERSION ERROR) as to_numeric_scale
+FROM test_safecast1;
+       numeric       | to_int2 | to_int4 | to_oid | to_int8 |  to_float4  |      to_float8       |     to_numeric      | to_numeric_scale 
+---------------------+---------+---------+--------+---------+-------------+----------------------+---------------------+------------------
+ 9223372036854775808 |         |         |        |         | 9.22337e+18 | 9.22337203685478e+18 | 9223372036854775808 |                 
+            Infinity |         |         |        |         |    Infinity |             Infinity |            Infinity |                 
+           -Infinity |         |         |        |         |   -Infinity |            -Infinity |           -Infinity |                 
+                 NaN |         |         |        |         |         NaN |                  NaN |                 NaN |              NaN
+(4 rows)
+
+SELECT col4 as num_arr,
+       CAST(col4 AS int2[] DEFAULT NULL ON CONVERSION ERROR) as int2arr,
+       CAST(col4 AS int4[] DEFAULT NULL ON CONVERSION ERROR) as int4arr,
+       CAST(col4 as int8[] DEFAULT NULL ON CONVERSION ERROR) as int8arr,
+       CAST(col4 as float4[] DEFAULT NULL ON CONVERSION ERROR) as f4arr,
+       CAST(col4 as float8[] DEFAULT NULL ON CONVERSION ERROR) as f8arr,
+       CAST(col4 as numeric(10,1)[] DEFAULT NULL ON CONVERSION ERROR) as numarr
+FROM test_safecast1;
+          num_arr           | int2arr | int4arr | int8arr |           f4arr            |           f8arr            | numarr 
+----------------------------+---------+---------+---------+----------------------------+----------------------------+--------
+ {11.1234}                  | {11}    | {11}    | {11}    | {11.1234}                  | {11.1234}                  | {11.1}
+ {11.1234,12,Infinity,NaN}  |         |         |         | {11.1234,12,Infinity,NaN}  | {11.1234,12,Infinity,NaN}  | 
+ {11.1234,12,-Infinity,NaN} |         |         |         | {11.1234,12,-Infinity,NaN} | {11.1234,12,-Infinity,NaN} | 
+ {11.1234,12,-Infinity,NaN} |         |         |         | {11.1234,12,-Infinity,NaN} | {11.1234,12,-Infinity,NaN} | 
+(4 rows)
+
+SELECT col1 as float4,
+       CAST(col1 AS int2 DEFAULT NULL ON CONVERSION ERROR) as to_int2,
+       CAST(col1 AS int4 DEFAULT NULL ON CONVERSION ERROR) as to_int4,
+       CAST(col1 AS oid DEFAULT NULL ON CONVERSION ERROR) as to_oid,
+       CAST(col1 as int8 DEFAULT NULL ON CONVERSION ERROR) as to_int8,
+       CAST(col1 as float4 DEFAULT NULL ON CONVERSION ERROR) as to_float4,
+       CAST(col1 as float8 DEFAULT NULL ON CONVERSION ERROR) as to_float8,
+       CAST(col1 as numeric DEFAULT NULL ON CONVERSION ERROR) as to_numeric,
+       CAST(col1 as numeric(10,1) DEFAULT NULL ON CONVERSION ERROR) as to_numeric_scale
+FROM test_safecast1;
+  float4   | to_int2 | to_int4 | to_oid | to_int8 | to_float4 |    to_float8     | to_numeric | to_numeric_scale 
+-----------+---------+---------+--------+---------+-----------+------------------+------------+------------------
+   11.1234 |      11 |      11 |        |      11 |   11.1234 | 11.1233997344971 |    11.1234 |             11.1
+  Infinity |         |         |        |         |  Infinity |         Infinity |   Infinity |                 
+ -Infinity |         |         |        |         | -Infinity |        -Infinity |  -Infinity |                 
+       NaN |         |         |        |         |       NaN |              NaN |        NaN |              NaN
+(4 rows)
+
+SELECT col2 as float8,
+       CAST(col2 AS int2 DEFAULT NULL ON CONVERSION ERROR) as to_int2,
+       CAST(col2 AS int4 DEFAULT NULL ON CONVERSION ERROR) as to_int4,
+       CAST(col2 AS oid DEFAULT NULL ON CONVERSION ERROR) as to_oid,
+       CAST(col2 as int8 DEFAULT NULL ON CONVERSION ERROR) as to_int8,
+       CAST(col2 as float4 DEFAULT NULL ON CONVERSION ERROR) as to_float4,
+       CAST(col2 as float8 DEFAULT NULL ON CONVERSION ERROR) as to_float8,
+       CAST(col2 as numeric DEFAULT NULL ON CONVERSION ERROR) as to_numeric,
+       CAST(col2 as numeric(10,1) DEFAULT NULL ON CONVERSION ERROR) as to_numeric_scale
+FROM test_safecast1;
+  float8   | to_int2 | to_int4 | to_oid | to_int8 | to_float4 | to_float8 | to_numeric | to_numeric_scale 
+-----------+---------+---------+--------+---------+-----------+-----------+------------+------------------
+   11.1234 |      11 |      11 |        |      11 |   11.1234 |   11.1234 |    11.1234 |             11.1
+  Infinity |         |         |        |         |  Infinity |  Infinity |   Infinity |                 
+ -Infinity |         |         |        |         | -Infinity | -Infinity |  -Infinity |                 
+       NaN |         |         |        |         |       NaN |       NaN |        NaN |              NaN
+(4 rows)
+
+-- date/timestamp/interval related safe type cast
+CREATE TABLE test_safecast2(
+  col0 date, col1 timestamp, col2 timestamptz,
+  col3 interval, col4 time, col5 timetz);
+INSERT INTO test_safecast2 VALUES
+('-infinity', '-infinity', '-infinity', '-infinity',
+  '2003-03-07 15:36:39 America/New_York', '2003-07-07 15:36:39 America/New_York'),
+('-infinity', 'infinity', 'infinity', 'infinity',
+  '11:59:59.99 PM', '11:59:59.99 PM PDT');
+SELECT col0 as date,
+       CAST(col0 AS timestamptz DEFAULT NULL ON CONVERSION ERROR) as to_timestamptz,
+       CAST(col0 AS date DEFAULT NULL ON CONVERSION ERROR) as to_date,
+       CAST(col0 AS time DEFAULT NULL ON CONVERSION ERROR) as to_times,
+       CAST(col0 AS timetz DEFAULT NULL ON CONVERSION ERROR) as to_timetz,
+       CAST(col0 AS timestamp(2) DEFAULT NULL ON CONVERSION ERROR) as to_timestamp_scale
+FROM test_safecast2;
+   date    | to_timestamptz |  to_date  | to_times | to_timetz | to_timestamp_scale 
+-----------+----------------+-----------+----------+-----------+--------------------
+ -infinity | -infinity      | -infinity |          |           | -infinity
+ -infinity | -infinity      | -infinity |          |           | -infinity
+(2 rows)
+
+SELECT col1 as timestamp,
+       CAST(col1 AS timestamptz DEFAULT NULL ON CONVERSION ERROR) as to_timestamptz,
+       CAST(col1 AS date DEFAULT NULL ON CONVERSION ERROR) as to_date,
+       CAST(col1 AS time DEFAULT NULL ON CONVERSION ERROR) as to_times,
+       CAST(col1 AS timetz DEFAULT NULL ON CONVERSION ERROR) as to_timetz,
+       CAST(col1 AS timestamp(2) DEFAULT NULL ON CONVERSION ERROR) as to_timestamp_scale
+FROM test_safecast2;
+ timestamp | to_timestamptz |  to_date  | to_times | to_timetz | to_timestamp_scale 
+-----------+----------------+-----------+----------+-----------+--------------------
+ -infinity | -infinity      | -infinity |          |           | -infinity
+ infinity  | infinity       | infinity  |          |           | infinity
+(2 rows)
+
+SELECT col2 as timestamptz,
+       CAST(col2 AS timestamptz DEFAULT NULL ON CONVERSION ERROR) as to_timestamptz,
+       CAST(col2 AS date DEFAULT NULL ON CONVERSION ERROR) as to_date,
+       CAST(col2 AS time DEFAULT NULL ON CONVERSION ERROR) as to_times,
+       CAST(col2 AS timetz DEFAULT NULL ON CONVERSION ERROR) as to_timetz,
+       CAST(col2 AS timestamp(2) DEFAULT NULL ON CONVERSION ERROR) as to_timestamp_scale
+FROM test_safecast2;
+ timestamptz | to_timestamptz |  to_date  | to_times | to_timetz | to_timestamp_scale 
+-------------+----------------+-----------+----------+-----------+--------------------
+ -infinity   | -infinity      | -infinity |          |           | -infinity
+ infinity    | infinity       | infinity  |          |           | infinity
+(2 rows)
+
+SELECT col3 as interval,
+       CAST(col3 AS timestamptz DEFAULT NULL ON CONVERSION ERROR) as to_timestamptz,
+       CAST(col3 AS date DEFAULT NULL ON CONVERSION ERROR) as to_date,
+       CAST(col3 AS time DEFAULT NULL ON CONVERSION ERROR) as to_times,
+       CAST(col3 AS timetz DEFAULT NULL ON CONVERSION ERROR) as to_timetz,
+       CAST(col3 AS timestamp(2) DEFAULT NULL ON CONVERSION ERROR) as to_timestamp_scale,
+       CAST(col3 AS interval(2) DEFAULT NULL ON CONVERSION ERROR) as to_interval_scale
+FROM test_safecast2;
+ interval  | to_timestamptz | to_date | to_times | to_timetz | to_timestamp_scale | to_interval_scale 
+-----------+----------------+---------+----------+-----------+--------------------+-------------------
+ -infinity |                |         |          |           |                    | -infinity
+ infinity  |                |         |          |           |                    | infinity
+(2 rows)
+
+SELECT col4 as time,
+       CAST(col4 AS time(2) DEFAULT NULL ON CONVERSION ERROR) as to_times,
+       CAST(col4 AS timetz DEFAULT NULL ON CONVERSION ERROR) IS NOT NULL as to_timetz,
+       CAST(col4 AS interval(2) DEFAULT NULL ON CONVERSION ERROR) as to_interval,
+       CAST(col4 AS interval(2) DEFAULT NULL ON CONVERSION ERROR) as to_interval_scale
+FROM test_safecast2;
+    time     |  to_times   | to_timetz |          to_interval          |       to_interval_scale       
+-------------+-------------+-----------+-------------------------------+-------------------------------
+ 15:36:39    | 15:36:39    | t         | @ 15 hours 36 mins 39 secs    | @ 15 hours 36 mins 39 secs
+ 23:59:59.99 | 23:59:59.99 | t         | @ 23 hours 59 mins 59.99 secs | @ 23 hours 59 mins 59.99 secs
+(2 rows)
+
+SELECT col5 as timetz,
+       CAST(col5 AS time DEFAULT NULL ON CONVERSION ERROR) as to_time,
+       CAST(col5 AS time(2) DEFAULT NULL ON CONVERSION ERROR) as to_time_scale,
+       CAST(col5 AS timetz DEFAULT NULL ON CONVERSION ERROR) as to_timetz,
+       CAST(col5 AS timetz(6) DEFAULT NULL ON CONVERSION ERROR) as to_timetz_scale,
+       CAST(col5 AS interval DEFAULT NULL ON CONVERSION ERROR) as to_interval,
+       CAST(col5 AS interval(2) DEFAULT NULL ON CONVERSION ERROR) as to_interval_scale
+FROM test_safecast2;
+     timetz     |   to_time   | to_time_scale |   to_timetz    | to_timetz_scale | to_interval | to_interval_scale 
+----------------+-------------+---------------+----------------+-----------------+-------------+-------------------
+ 15:36:39-04    | 15:36:39    | 15:36:39      | 15:36:39-04    | 15:36:39-04     |             | 
+ 23:59:59.99-07 | 23:59:59.99 | 23:59:59.99   | 23:59:59.99-07 | 23:59:59.99-07  |             | 
+(2 rows)
+
+CREATE TABLE test_safecast3(col0 jsonb);
+INSERT INTO test_safecast3(col0) VALUES ('"test"');
+SELECT col0 as jsonb,
+       CAST(col0 AS integer DEFAULT NULL ON CONVERSION ERROR) as to_integer,
+       CAST(col0 AS numeric DEFAULT NULL ON CONVERSION ERROR) as to_numeric,
+       CAST(col0 AS bigint DEFAULT NULL ON CONVERSION ERROR) as to_int8,
+       CAST(col0 AS float4 DEFAULT NULL ON CONVERSION ERROR) as to_float4,
+       CAST(col0 AS float8 DEFAULT NULL ON CONVERSION ERROR) as to_float8,
+       CAST(col0 AS boolean DEFAULT NULL ON CONVERSION ERROR) as to_bool,
+       CAST(col0 AS smallint DEFAULT NULL ON CONVERSION ERROR) as to_smallint
+FROM test_safecast3;
+ jsonb  | to_integer | to_numeric | to_int8 | to_float4 | to_float8 | to_bool | to_smallint 
+--------+------------+------------+---------+-----------+-----------+---------+-------------
+ "test" |            |            |         |           |           |         |            
+(1 row)
+
+-- test deparse
+SET datestyle TO ISO, YMD;
+CREATE VIEW safecastview AS
+SELECT CAST('1234' as char(3) DEFAULT -1111 ON CONVERSION ERROR),
+       CAST(1 as date DEFAULT (('2025-Dec-06'::date + random(min=>1, max=>1::int))) ON CONVERSION ERROR) as cast0,
+       CAST(ARRAY[['1'], ['three'],['a']] AS int[] DEFAULT '{1,2}' ON CONVERSION ERROR) as cast1,
+       CAST(ARRAY[['1', '2'], ['three', 'a']] AS date[] DEFAULT NULL ON CONVERSION ERROR) as cast2,
+       CAST(ARRAY['three'] AS INT[] DEFAULT '{1,2}' ON CONVERSION ERROR) as cast3;
+\sv safecastview
+CREATE OR REPLACE VIEW public.safecastview AS
+ SELECT CAST('1234' AS character(3) DEFAULT '-1111'::integer::character(3) ON CONVERSION ERROR) AS bpchar,
+    CAST(1 AS date DEFAULT '2025-12-06'::date + random(min => 1, max => 1) ON CONVERSION ERROR) AS cast0,
+    CAST(ARRAY[ARRAY[1], ARRAY['three'], ARRAY['a']] AS integer[] DEFAULT '{1,2}'::integer[] ON CONVERSION ERROR) AS cast1,
+    CAST(ARRAY[ARRAY['1', '2'], ARRAY['three', 'a']] AS date[] DEFAULT NULL::date[] ON CONVERSION ERROR) AS cast2,
+    CAST(ARRAY['three'] AS integer[] DEFAULT '{1,2}'::integer[] ON CONVERSION ERROR) AS cast3
+SELECT * FROM safecastview;
+ bpchar |   cast0    | cast1 | cast2 | cast3 
+--------+------------+-------+-------+-------
+ 123    | 2025-12-07 | {1,2} |       | {1,2}
+(1 row)
+
+CREATE VIEW safecastview1 AS
+SELECT CAST(ARRAY[['1'], ['three'],['a']] AS d_int_arr
+            DEFAULT '{41,43}' ON CONVERSION ERROR) as cast1,
+       CAST(ARRAY[['1', '2', 1.1], ['three', true, B'01']] AS d_int_arr
+            DEFAULT '{41,43}' ON CONVERSION ERROR) as cast2;
+\sv safecastview1
+CREATE OR REPLACE VIEW public.safecastview1 AS
+ SELECT CAST(ARRAY[ARRAY[1], ARRAY['three'], ARRAY['a']] AS d_int_arr DEFAULT '{41,43}'::integer[]::d_int_arr ON CONVERSION ERROR) AS cast1,
+    CAST(ARRAY[ARRAY[1, 2, 1.1::integer], ARRAY['three', true, '01'::"bit"]] AS d_int_arr DEFAULT '{41,43}'::integer[]::d_int_arr ON CONVERSION ERROR) AS cast2
+SELECT * FROM safecastview1;
+  cast1  |  cast2  
+---------+---------
+ {41,43} | {41,43}
+(1 row)
+
+RESET datestyle;
+--test CAST DEFAULT expression mutability
+CREATE INDEX cast_error_idx ON test_safecast3((CAST(col0 as int DEFAULT random(min=>1, max=>1) ON CONVERSION ERROR)));
+ERROR:  functions in index expression must be marked IMMUTABLE
+CREATE INDEX cast_error_idx ON test_safecast3((CAST(col0 as xid DEFAULT NULL ON CONVERSION ERROR)));
+ERROR:  data type xid has no default operator class for access method "btree"
+HINT:  You must specify an operator class for the index or define a default operator class for the data type.
+CREATE INDEX test_safecast3_idx ON test_safecast3((CAST(col0 as int DEFAULT NULL ON CONVERSION ERROR))); --ok
+SELECT pg_get_indexdef('test_safecast3_idx'::regclass);
+                                                             pg_get_indexdef                                                              
+------------------------------------------------------------------------------------------------------------------------------------------
+ CREATE INDEX test_safecast3_idx ON public.test_safecast3 USING btree ((CAST(col0 AS integer DEFAULT NULL::integer ON CONVERSION ERROR)))
+(1 row)
+
+DROP TABLE test_safecast;
+DROP TABLE test_safecast1;
+DROP TABLE test_safecast2;
+DROP TABLE test_safecast3;
+DROP TABLE tcast;
+DROP FUNCTION ret_int8;
+DROP FUNCTION ret_setint;
+DROP TYPE comp_domain_with_typmod;
+DROP TYPE comp2;
+DROP DOMAIN d_varchar;
+DROP DOMAIN d_int42;
+DROP DOMAIN d_char3_not_null;
+RESET extra_float_digits;
diff --git a/src/test/regress/expected/create_cast.out b/src/test/regress/expected/create_cast.out
index 0e69644bca2..0054ed0ef67 100644
--- a/src/test/regress/expected/create_cast.out
+++ b/src/test/regress/expected/create_cast.out
@@ -88,6 +88,11 @@ SELECT 1234::int4::casttesttype; -- Should work now
  bar1234
 (1 row)
 
+SELECT CAST(1234::int4 AS casttesttype DEFAULT NULL ON CONVERSION ERROR); -- error
+ERROR:  cannot cast type integer to casttesttype when DEFAULT expression is specified in CAST ... ON CONVERSION ERROR
+LINE 1: SELECT CAST(1234::int4 AS casttesttype DEFAULT NULL ON CONVE...
+                    ^
+HINT:  Safe type cast for user-defined types are not yet supported
 -- check dependencies generated for that
 SELECT pg_describe_object(classid, objid, objsubid) as obj,
        pg_describe_object(refclassid, refobjid, refobjsubid) as objref,
diff --git a/src/test/regress/expected/equivclass.out b/src/test/regress/expected/equivclass.out
index ad8ab294ff6..5aee2c7a9fb 100644
--- a/src/test/regress/expected/equivclass.out
+++ b/src/test/regress/expected/equivclass.out
@@ -95,6 +95,13 @@ create function int8alias1cmp(int8, int8alias1) returns int
   strict immutable language internal as 'btint8cmp';
 alter operator family integer_ops using btree add
   function 1 int8alias1cmp (int8, int8alias1);
+-- int8alias2 binary-coercible to int8. so this is ok
+select cast('1'::int8 as int8alias2 default null on conversion error);
+ int8alias2 
+------------
+ 1
+(1 row)
+
 create table ec0 (ff int8 primary key, f1 int8, f2 int8);
 create table ec1 (ff int8 primary key, f1 int8alias1, f2 int8alias2);
 create table ec2 (xf int8 primary key, x1 int8alias1, x2 int8alias2);
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
index cc6d799bcea..0b031a37c36 100644
--- a/src/test/regress/parallel_schedule
+++ b/src/test/regress/parallel_schedule
@@ -81,7 +81,7 @@ test: create_table_like alter_generic alter_operator misc async dbsize merge mis
 # collate.linux.utf8 and collate.icu.utf8 tests cannot be run in parallel with each other
 # psql depends on create_am
 # amutils depends on geometry, create_index_spgist, hash_index, brin
-test: rules psql psql_crosstab psql_pipeline amutils stats_ext collate.linux.utf8 collate.windows.win1252
+test: rules psql psql_crosstab psql_pipeline amutils stats_ext collate.linux.utf8 collate.windows.win1252 cast
 
 # ----------
 # Run these alone so they don't run out of parallel workers
diff --git a/src/test/regress/sql/cast.sql b/src/test/regress/sql/cast.sql
new file mode 100644
index 00000000000..9b6f3cc0649
--- /dev/null
+++ b/src/test/regress/sql/cast.sql
@@ -0,0 +1,350 @@
+SET extra_float_digits = 0;
+
+-- CAST DEFAULT ON CONVERSION ERROR
+SELECT CAST(B'01' AS date DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST(BIT'01' AS date DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST(TRUE AS date DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST(1.1 AS date DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST(1 AS date DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST(1111 AS "char" DEFAULT 'A' ON CONVERSION ERROR);
+
+--test source expression is a unknown const
+VALUES (CAST('error' AS integer ERROR ON CONVERSION ERROR)); --error
+VALUES (CAST('error' AS integer NULL ON CONVERSION ERROR));
+VALUES (CAST('error' AS integer DEFAULT 42 ON CONVERSION ERROR));
+SELECT CAST('a' as int DEFAULT 18 ON CONVERSION ERROR);
+SELECT CAST('a' as int DEFAULT sum(1) ON CONVERSION ERROR); --error
+SELECT CAST('a' as int DEFAULT sum(1) over() ON CONVERSION ERROR); --error
+SELECT CAST('a' as int DEFAULT (SELECT NULL) ON CONVERSION ERROR); --error
+SELECT CAST('a' as int DEFAULT 'b' ON CONVERSION ERROR); --error
+SELECT CAST('a'::int as int DEFAULT NULL ON CONVERSION ERROR); --error
+
+--the default expression’s collation should match the collation of the cast
+--target type
+VALUES (CAST('error' AS text DEFAULT '1' COLLATE "C" ON CONVERSION ERROR));
+
+VALUES (CAST('error' AS int2vector DEFAULT '1 3'  ON CONVERSION ERROR));
+VALUES (CAST('error' AS int2vector[] DEFAULT '{1 3}'  ON CONVERSION ERROR));
+
+-- test source expression contain subquery
+SELECT CAST((SELECT b FROM generate_series(1, 1), (VALUES('H')) s(b))
+            AS int2vector[] DEFAULT '{1 3}'  ON CONVERSION ERROR);
+SELECT CAST((SELECT ARRAY((SELECT b FROM generate_series(1, 2) g, (VALUES('H')) s(b))))
+            AS INT[]
+            DEFAULT NULL ON CONVERSION ERROR);
+
+CREATE FUNCTION ret_int8() RETURNS BIGINT AS
+$$
+BEGIN RETURN 2147483648; END;
+$$
+LANGUAGE plpgsql IMMUTABLE;
+
+SELECT CAST('a' as int DEFAULT ret_int8() ON CONVERSION ERROR); --error
+SELECT CAST('a' as date DEFAULT ret_int8() ON CONVERSION ERROR); --error
+
+-- DEFAULT expression can not be set-returning
+CREATE FUNCTION ret_setint() RETURNS SETOF integer AS
+$$
+BEGIN RETURN QUERY EXECUTE 'select 1 union all select 1'; END;
+$$
+LANGUAGE plpgsql IMMUTABLE;
+
+CREATE TABLE tcast(a text[], b int GENERATED BY DEFAULT AS IDENTITY);
+INSERT INTO tcast VALUES ('{12}'), ('{1,a, b}'), ('{{1,2}, {c,d}}'), ('{13}');
+SELECT CAST('a' as int DEFAULT ret_setint() ON CONVERSION ERROR) FROM tcast; --error
+SELECT CAST(t AS text[] DEFAULT '{21,22, ' || b || '}' ON CONVERSION ERROR) FROM tcast as t;
+SELECT CAST(t.a AS int[] DEFAULT '{21,22}'::int[] || b ON CONVERSION ERROR) FROM tcast as t;
+
+-- test with user-defined type, domain, array over domain, domain over array
+CREATE DOMAIN d_int42 as int check (value = 42) NOT NULL;
+CREATE DOMAIN d_char3_not_null as char(3) NOT NULL;
+CREATE DOMAIN d_varchar as varchar(3) NOT NULL;
+CREATE DOMAIN d_int_arr as int[] check (value = '{41, 43}') NOT NULL;
+CREATE TYPE comp_domain_with_typmod AS (a d_char3_not_null, b int);
+CREATE TYPE comp2 AS (a d_varchar);
+SELECT CAST('(NULL)' AS comp2 DEFAULT '(1232)' ON CONVERSION ERROR); --error
+SELECT CAST('(NULL)' AS comp2 DEFAULT '(123)' ON CONVERSION ERROR);
+SELECT CAST(11 AS d_int42 DEFAULT 41 ON CONVERSION ERROR); --error
+SELECT CAST(11 AS d_int42 DEFAULT 42 ON CONVERSION ERROR);
+SELECT CAST(NULL AS d_int42 DEFAULT NULL ON CONVERSION ERROR); --error
+SELECT CAST(NULL AS d_int42 DEFAULT 42 ON CONVERSION ERROR);
+SELECT CAST('(,42)' AS comp_domain_with_typmod DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('(NULL,42)' AS comp_domain_with_typmod DEFAULT '(1,2)' ON CONVERSION ERROR);
+SELECT CAST('(NULL,42)' AS comp_domain_with_typmod DEFAULT '(1234,2)' ON CONVERSION ERROR); --error
+
+SELECT CAST(ARRAY[42,41] AS d_int42[] DEFAULT '{42, 42}' ON CONVERSION ERROR);
+SELECT CAST(ARRAY[42,41] AS d_int_arr DEFAULT '{41, 43}' ON CONVERSION ERROR);
+
+-- test array coerce
+SELECT CAST(array['a'::text] AS int[] DEFAULT NULL ON CONVERSION ERROR); --error
+SELECT CAST(array['a'] AS int[] DEFAULT ARRAY[1] ON CONVERSION ERROR);
+SELECT CAST(array[11.12] AS date[] DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST(array[11111111111111111] AS int[] DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST(array[['abc'],[456]] AS int[] DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('{123,abc,456}' AS int[] DEFAULT '{-789}' ON CONVERSION ERROR);
+SELECT CAST('{234,def,567}'::text[] AS integer[] DEFAULT '{-1011}' ON CONVERSION ERROR);
+SELECT CAST(ARRAY[['1'], ['three'],['a']] AS int[] DEFAULT '{1,2}' ON CONVERSION ERROR);
+SELECT CAST(ARRAY[['1', '2'], ['three', 'a']] AS int[] DEFAULT '{21,22}' ON CONVERSION ERROR); --ok
+SELECT CAST(ARRAY[['1', '2'], ['three'::int, 'a']] AS int[] DEFAULT '{21,22}' ON CONVERSION ERROR); --error
+SELECT CAST(ARRAY[1, 'three'::int] AS int[] DEFAULT '{21,22}' ON CONVERSION ERROR); --error
+
+-----safe cast with geometry data type
+SELECT CAST('(1,2)'::point AS box DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('[(NaN,1),(NaN,infinity)]'::lseg AS point DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('[(1e+300,Infinity),(1e+300,Infinity)]'::lseg AS point DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('[(1,2),(3,4)]'::path as polygon DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('(NaN,1.0,NaN,infinity)'::box AS point DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('(2.0,2.0,0.0,0.0)'::box AS lseg DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('(2.0,2.0,0.0,0.0)'::box AS polygon DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('(2.0,2.0,0.0,0.0)'::box AS path DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('(2.0,infinity,NaN,infinity)'::box AS circle DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('(NaN,0.0),(2.0,4.0),(0.0,infinity)'::polygon AS point DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('(2.0,0.0),(2.0,4.0),(0.0,0.0)'::polygon AS path DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('(2.0,0.0),(2.0,4.0),(0.0,0.0)'::polygon AS box DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('(NaN,infinity),(2.0,4.0),(0.0,infinity)'::polygon AS circle DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('<(5,1),3>'::circle AS point DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('<(3,5),0>'::circle as box DEFAULT NULL ON CONVERSION ERROR);
+
+-- not supported because the cast from circle to polygon is implemented as a SQL
+-- function, which cannot be error-safe.
+SELECT CAST('<(3,5),0>'::circle as polygon DEFAULT NULL ON CONVERSION ERROR);
+
+-----safe cast from/to money type is not supported, all the following would result error
+SELECT CAST(NULL::int8 AS money DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST(NULL::int4 AS money DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST(NULL::numeric AS money DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST(NULL::money AS numeric DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST(NULL::money[] AS numeric[] DEFAULT NULL ON CONVERSION ERROR);
+
+-----safe cast from bytea type to other data types
+SELECT CAST ('\x112233445566778899'::bytea AS int8 DEFAULT 19 ON CONVERSION ERROR);
+SELECT CAST('\x123456789A'::bytea AS int4 DEFAULT 20 ON CONVERSION ERROR);
+SELECT CAST('\x123456'::bytea AS int2 DEFAULT 21 ON CONVERSION ERROR);
+
+-----safe cast from bit type to other data types
+SELECT CAST('111111111100001'::bit(100) AS INT DEFAULT 22 ON CONVERSION ERROR);
+SELECT CAST ('111111111100001'::bit(100) AS INT8 DEFAULT 23 ON CONVERSION ERROR);
+
+-----safe cast from text type to other data types
+select CAST('a.b.c.d'::text as regclass default NULL on conversion error);
+
+CREATE TABLE test_safecast(col0 text);
+INSERT INTO test_safecast(col0) VALUES ('<value>one</value');
+
+SELECT col0 as text,
+       CAST(col0 AS regclass DEFAULT NULL ON CONVERSION ERROR) as to_regclass,
+       CAST(col0 AS regclass DEFAULT NULL ON CONVERSION ERROR) IS NULL as expect_true,
+       CAST(col0 AS "char"  DEFAULT NULL ON CONVERSION ERROR) as to_char,
+       CAST(col0 AS name DEFAULT NULL ON CONVERSION ERROR) as to_name,
+       CAST(col0 AS xml DEFAULT NULL ON CONVERSION ERROR) as to_xml
+FROM test_safecast;
+
+SELECT CAST('192.168.1.x' as inet DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('192.168.1.2/30' as cidr DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('22:00:5c:08:55:08:01:02'::macaddr8 as macaddr DEFAULT NULL ON CONVERSION ERROR);
+
+-----safe cast betweeen range data types
+SELECT CAST('[1,2]'::int4range AS int4multirange DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('[1,2]'::int8range AS int8multirange DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('[1,2]'::numrange  AS nummultirange DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('[-infinity,infinity]'::daterange AS datemultirange DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('[-infinity,infinity]'::tsrange AS tsmultirange DEFAULT NULL ON CONVERSION ERROR);
+SELECT CAST('[-infinity,infinity]'::tstzrange AS tstzmultirange DEFAULT NULL ON CONVERSION ERROR);
+
+-----safe cast betweeen numeric data types
+CREATE TABLE test_safecast1(
+  col1 float4, col2 float8, col3 numeric, col4 numeric[],
+  col5 int2 default 32767,
+  col6 int4 default 32768,
+  col7 int8 default 4294967296);
+INSERT INTO test_safecast1 VALUES('11.1234', '11.1234', '9223372036854775808', '{11.1234}'::numeric[]);
+INSERT INTO test_safecast1 VALUES('inf', 'inf', 'inf', '{11.1234, 12, inf, NaN}'::numeric[]);
+INSERT INTO test_safecast1 VALUES('-inf', '-inf', '-inf', '{11.1234, 12, -inf, NaN}'::numeric[]);
+INSERT INTO test_safecast1 VALUES('NaN', 'NaN', 'NaN', '{11.1234, 12, -inf, NaN}'::numeric[]);
+
+SELECT col5 as int2,
+       CAST(col5 AS int2 DEFAULT NULL ON CONVERSION ERROR) as to_int2,
+       CAST(col5 AS int4 DEFAULT NULL ON CONVERSION ERROR) as to_int4,
+       CAST(col5 AS oid DEFAULT NULL ON CONVERSION ERROR) as to_oid,
+       CAST(col5 as int8 DEFAULT NULL ON CONVERSION ERROR) as to_int8,
+       CAST(col5 as float4 DEFAULT NULL ON CONVERSION ERROR) as to_float4,
+       CAST(col5 as float8 DEFAULT NULL ON CONVERSION ERROR) as to_float8,
+       CAST(col5 as numeric DEFAULT NULL ON CONVERSION ERROR) as to_numeric,
+       CAST(col5 as numeric(10,1) DEFAULT NULL ON CONVERSION ERROR) as to_numeric_scale
+FROM test_safecast1;
+
+SELECT col6 as int4,
+       CAST(col6 AS int2 DEFAULT NULL ON CONVERSION ERROR) as to_int2,
+       CAST(col6 AS int4 DEFAULT NULL ON CONVERSION ERROR) as to_int4,
+       CAST(col6 AS oid DEFAULT NULL ON CONVERSION ERROR) as to_oid,
+       CAST(col6 as int8 DEFAULT NULL ON CONVERSION ERROR) as to_int8,
+       CAST(col6 as float4 DEFAULT NULL ON CONVERSION ERROR) as to_float4,
+       CAST(col6 as float8 DEFAULT NULL ON CONVERSION ERROR) as to_float8,
+       CAST(col6 as numeric DEFAULT NULL ON CONVERSION ERROR) as to_numeric,
+       CAST(col6 as numeric(10,1) DEFAULT NULL ON CONVERSION ERROR) as to_numeric_scale
+FROM test_safecast1;
+
+SELECT col7 as int8,
+       CAST(col7 AS int2 DEFAULT NULL ON CONVERSION ERROR) as to_int2,
+       CAST(col7 AS int4 DEFAULT NULL ON CONVERSION ERROR) as to_int4,
+       CAST(col7 AS oid DEFAULT NULL ON CONVERSION ERROR) as to_oid,
+       CAST(col7 as int8 DEFAULT NULL ON CONVERSION ERROR) as to_int8,
+       CAST(col7 as float4 DEFAULT NULL ON CONVERSION ERROR) as to_float4,
+       CAST(col7 as float8 DEFAULT NULL ON CONVERSION ERROR) as to_float8,
+       CAST(col7 as numeric DEFAULT NULL ON CONVERSION ERROR) as to_numeric,
+       CAST(col7 as numeric(10,1) DEFAULT NULL ON CONVERSION ERROR) as to_numeric_scale
+FROM test_safecast1;
+
+SELECT col3 as numeric,
+       CAST(col3 AS int2 DEFAULT NULL ON CONVERSION ERROR) as to_int2,
+       CAST(col3 AS int4 DEFAULT NULL ON CONVERSION ERROR) as to_int4,
+       CAST(col3 AS oid DEFAULT NULL ON CONVERSION ERROR) as to_oid,
+       CAST(col3 as int8 DEFAULT NULL ON CONVERSION ERROR) as to_int8,
+       CAST(col3 as float4 DEFAULT NULL ON CONVERSION ERROR) as to_float4,
+       CAST(col3 as float8 DEFAULT NULL ON CONVERSION ERROR) as to_float8,
+       CAST(col3 as numeric DEFAULT NULL ON CONVERSION ERROR) as to_numeric,
+       CAST(col3 as numeric(10,1) DEFAULT NULL ON CONVERSION ERROR) as to_numeric_scale
+FROM test_safecast1;
+
+SELECT col4 as num_arr,
+       CAST(col4 AS int2[] DEFAULT NULL ON CONVERSION ERROR) as int2arr,
+       CAST(col4 AS int4[] DEFAULT NULL ON CONVERSION ERROR) as int4arr,
+       CAST(col4 as int8[] DEFAULT NULL ON CONVERSION ERROR) as int8arr,
+       CAST(col4 as float4[] DEFAULT NULL ON CONVERSION ERROR) as f4arr,
+       CAST(col4 as float8[] DEFAULT NULL ON CONVERSION ERROR) as f8arr,
+       CAST(col4 as numeric(10,1)[] DEFAULT NULL ON CONVERSION ERROR) as numarr
+FROM test_safecast1;
+
+SELECT col1 as float4,
+       CAST(col1 AS int2 DEFAULT NULL ON CONVERSION ERROR) as to_int2,
+       CAST(col1 AS int4 DEFAULT NULL ON CONVERSION ERROR) as to_int4,
+       CAST(col1 AS oid DEFAULT NULL ON CONVERSION ERROR) as to_oid,
+       CAST(col1 as int8 DEFAULT NULL ON CONVERSION ERROR) as to_int8,
+       CAST(col1 as float4 DEFAULT NULL ON CONVERSION ERROR) as to_float4,
+       CAST(col1 as float8 DEFAULT NULL ON CONVERSION ERROR) as to_float8,
+       CAST(col1 as numeric DEFAULT NULL ON CONVERSION ERROR) as to_numeric,
+       CAST(col1 as numeric(10,1) DEFAULT NULL ON CONVERSION ERROR) as to_numeric_scale
+FROM test_safecast1;
+
+SELECT col2 as float8,
+       CAST(col2 AS int2 DEFAULT NULL ON CONVERSION ERROR) as to_int2,
+       CAST(col2 AS int4 DEFAULT NULL ON CONVERSION ERROR) as to_int4,
+       CAST(col2 AS oid DEFAULT NULL ON CONVERSION ERROR) as to_oid,
+       CAST(col2 as int8 DEFAULT NULL ON CONVERSION ERROR) as to_int8,
+       CAST(col2 as float4 DEFAULT NULL ON CONVERSION ERROR) as to_float4,
+       CAST(col2 as float8 DEFAULT NULL ON CONVERSION ERROR) as to_float8,
+       CAST(col2 as numeric DEFAULT NULL ON CONVERSION ERROR) as to_numeric,
+       CAST(col2 as numeric(10,1) DEFAULT NULL ON CONVERSION ERROR) as to_numeric_scale
+FROM test_safecast1;
+
+-- date/timestamp/interval related safe type cast
+CREATE TABLE test_safecast2(
+  col0 date, col1 timestamp, col2 timestamptz,
+  col3 interval, col4 time, col5 timetz);
+INSERT INTO test_safecast2 VALUES
+('-infinity', '-infinity', '-infinity', '-infinity',
+  '2003-03-07 15:36:39 America/New_York', '2003-07-07 15:36:39 America/New_York'),
+('-infinity', 'infinity', 'infinity', 'infinity',
+  '11:59:59.99 PM', '11:59:59.99 PM PDT');
+
+SELECT col0 as date,
+       CAST(col0 AS timestamptz DEFAULT NULL ON CONVERSION ERROR) as to_timestamptz,
+       CAST(col0 AS date DEFAULT NULL ON CONVERSION ERROR) as to_date,
+       CAST(col0 AS time DEFAULT NULL ON CONVERSION ERROR) as to_times,
+       CAST(col0 AS timetz DEFAULT NULL ON CONVERSION ERROR) as to_timetz,
+       CAST(col0 AS timestamp(2) DEFAULT NULL ON CONVERSION ERROR) as to_timestamp_scale
+FROM test_safecast2;
+
+SELECT col1 as timestamp,
+       CAST(col1 AS timestamptz DEFAULT NULL ON CONVERSION ERROR) as to_timestamptz,
+       CAST(col1 AS date DEFAULT NULL ON CONVERSION ERROR) as to_date,
+       CAST(col1 AS time DEFAULT NULL ON CONVERSION ERROR) as to_times,
+       CAST(col1 AS timetz DEFAULT NULL ON CONVERSION ERROR) as to_timetz,
+       CAST(col1 AS timestamp(2) DEFAULT NULL ON CONVERSION ERROR) as to_timestamp_scale
+FROM test_safecast2;
+
+SELECT col2 as timestamptz,
+       CAST(col2 AS timestamptz DEFAULT NULL ON CONVERSION ERROR) as to_timestamptz,
+       CAST(col2 AS date DEFAULT NULL ON CONVERSION ERROR) as to_date,
+       CAST(col2 AS time DEFAULT NULL ON CONVERSION ERROR) as to_times,
+       CAST(col2 AS timetz DEFAULT NULL ON CONVERSION ERROR) as to_timetz,
+       CAST(col2 AS timestamp(2) DEFAULT NULL ON CONVERSION ERROR) as to_timestamp_scale
+FROM test_safecast2;
+
+SELECT col3 as interval,
+       CAST(col3 AS timestamptz DEFAULT NULL ON CONVERSION ERROR) as to_timestamptz,
+       CAST(col3 AS date DEFAULT NULL ON CONVERSION ERROR) as to_date,
+       CAST(col3 AS time DEFAULT NULL ON CONVERSION ERROR) as to_times,
+       CAST(col3 AS timetz DEFAULT NULL ON CONVERSION ERROR) as to_timetz,
+       CAST(col3 AS timestamp(2) DEFAULT NULL ON CONVERSION ERROR) as to_timestamp_scale,
+       CAST(col3 AS interval(2) DEFAULT NULL ON CONVERSION ERROR) as to_interval_scale
+FROM test_safecast2;
+
+SELECT col4 as time,
+       CAST(col4 AS time(2) DEFAULT NULL ON CONVERSION ERROR) as to_times,
+       CAST(col4 AS timetz DEFAULT NULL ON CONVERSION ERROR) IS NOT NULL as to_timetz,
+       CAST(col4 AS interval(2) DEFAULT NULL ON CONVERSION ERROR) as to_interval,
+       CAST(col4 AS interval(2) DEFAULT NULL ON CONVERSION ERROR) as to_interval_scale
+FROM test_safecast2;
+
+SELECT col5 as timetz,
+       CAST(col5 AS time DEFAULT NULL ON CONVERSION ERROR) as to_time,
+       CAST(col5 AS time(2) DEFAULT NULL ON CONVERSION ERROR) as to_time_scale,
+       CAST(col5 AS timetz DEFAULT NULL ON CONVERSION ERROR) as to_timetz,
+       CAST(col5 AS timetz(6) DEFAULT NULL ON CONVERSION ERROR) as to_timetz_scale,
+       CAST(col5 AS interval DEFAULT NULL ON CONVERSION ERROR) as to_interval,
+       CAST(col5 AS interval(2) DEFAULT NULL ON CONVERSION ERROR) as to_interval_scale
+FROM test_safecast2;
+
+CREATE TABLE test_safecast3(col0 jsonb);
+INSERT INTO test_safecast3(col0) VALUES ('"test"');
+SELECT col0 as jsonb,
+       CAST(col0 AS integer DEFAULT NULL ON CONVERSION ERROR) as to_integer,
+       CAST(col0 AS numeric DEFAULT NULL ON CONVERSION ERROR) as to_numeric,
+       CAST(col0 AS bigint DEFAULT NULL ON CONVERSION ERROR) as to_int8,
+       CAST(col0 AS float4 DEFAULT NULL ON CONVERSION ERROR) as to_float4,
+       CAST(col0 AS float8 DEFAULT NULL ON CONVERSION ERROR) as to_float8,
+       CAST(col0 AS boolean DEFAULT NULL ON CONVERSION ERROR) as to_bool,
+       CAST(col0 AS smallint DEFAULT NULL ON CONVERSION ERROR) as to_smallint
+FROM test_safecast3;
+
+-- test deparse
+SET datestyle TO ISO, YMD;
+CREATE VIEW safecastview AS
+SELECT CAST('1234' as char(3) DEFAULT -1111 ON CONVERSION ERROR),
+       CAST(1 as date DEFAULT (('2025-Dec-06'::date + random(min=>1, max=>1::int))) ON CONVERSION ERROR) as cast0,
+       CAST(ARRAY[['1'], ['three'],['a']] AS int[] DEFAULT '{1,2}' ON CONVERSION ERROR) as cast1,
+       CAST(ARRAY[['1', '2'], ['three', 'a']] AS date[] DEFAULT NULL ON CONVERSION ERROR) as cast2,
+       CAST(ARRAY['three'] AS INT[] DEFAULT '{1,2}' ON CONVERSION ERROR) as cast3;
+\sv safecastview
+SELECT * FROM safecastview;
+
+CREATE VIEW safecastview1 AS
+SELECT CAST(ARRAY[['1'], ['three'],['a']] AS d_int_arr
+            DEFAULT '{41,43}' ON CONVERSION ERROR) as cast1,
+       CAST(ARRAY[['1', '2', 1.1], ['three', true, B'01']] AS d_int_arr
+            DEFAULT '{41,43}' ON CONVERSION ERROR) as cast2;
+\sv safecastview1
+SELECT * FROM safecastview1;
+
+RESET datestyle;
+
+--test CAST DEFAULT expression mutability
+CREATE INDEX cast_error_idx ON test_safecast3((CAST(col0 as int DEFAULT random(min=>1, max=>1) ON CONVERSION ERROR)));
+CREATE INDEX cast_error_idx ON test_safecast3((CAST(col0 as xid DEFAULT NULL ON CONVERSION ERROR)));
+CREATE INDEX test_safecast3_idx ON test_safecast3((CAST(col0 as int DEFAULT NULL ON CONVERSION ERROR))); --ok
+SELECT pg_get_indexdef('test_safecast3_idx'::regclass);
+
+DROP TABLE test_safecast;
+DROP TABLE test_safecast1;
+DROP TABLE test_safecast2;
+DROP TABLE test_safecast3;
+DROP TABLE tcast;
+DROP FUNCTION ret_int8;
+DROP FUNCTION ret_setint;
+DROP TYPE comp_domain_with_typmod;
+DROP TYPE comp2;
+DROP DOMAIN d_varchar;
+DROP DOMAIN d_int42;
+DROP DOMAIN d_char3_not_null;
+RESET extra_float_digits;
diff --git a/src/test/regress/sql/create_cast.sql b/src/test/regress/sql/create_cast.sql
index 32187853cc7..0a15a795d87 100644
--- a/src/test/regress/sql/create_cast.sql
+++ b/src/test/regress/sql/create_cast.sql
@@ -62,6 +62,7 @@ $$ SELECT ('bar'::text || $1::text); $$;
 
 CREATE CAST (int4 AS casttesttype) WITH FUNCTION bar_int4_text(int4) AS IMPLICIT;
 SELECT 1234::int4::casttesttype; -- Should work now
+SELECT CAST(1234::int4 AS casttesttype DEFAULT NULL ON CONVERSION ERROR); -- error
 
 -- check dependencies generated for that
 SELECT pg_describe_object(classid, objid, objsubid) as obj,
diff --git a/src/test/regress/sql/equivclass.sql b/src/test/regress/sql/equivclass.sql
index 7fc2159349b..5ad1d26311d 100644
--- a/src/test/regress/sql/equivclass.sql
+++ b/src/test/regress/sql/equivclass.sql
@@ -98,6 +98,9 @@ create function int8alias1cmp(int8, int8alias1) returns int
 alter operator family integer_ops using btree add
   function 1 int8alias1cmp (int8, int8alias1);
 
+-- int8alias2 binary-coercible to int8. so this is ok
+select cast('1'::int8 as int8alias2 default null on conversion error);
+
 create table ec0 (ff int8 primary key, f1 int8, f2 int8);
 create table ec1 (ff int8 primary key, f1 int8alias1, f2 int8alias2);
 create table ec2 (xf int8 primary key, x1 int8alias1, x2 int8alias2);
diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list
index 9dd65b10254..44bba2e819f 100644
--- a/src/tools/pgindent/typedefs.list
+++ b/src/tools/pgindent/typedefs.list
@@ -2675,6 +2675,9 @@ STRLEN
 SV
 SYNCHRONIZATION_BARRIER
 SYSTEM_INFO
+SafeTypeCast
+SafeTypeCastExpr
+SafeTypeCastState
 SampleScan
 SampleScanGetSampleSize_function
 SampleScanState
-- 
2.34.1

