diff --git a/src/backend/partitioning/partprune.c b/src/backend/partitioning/partprune.c
index f954b92a6b..2d2f88e880 100644
--- a/src/backend/partitioning/partprune.c
+++ b/src/backend/partitioning/partprune.c
@@ -1690,7 +1690,7 @@ match_clause_to_partition_key(RelOptInfo *rel,
 				elem_exprs = lappend(elem_exprs, elem_expr);
 			}
 		}
-		else
+		else if (IsA(rightop, ArrayExpr))
 		{
 			ArrayExpr  *arrexpr = castNode(ArrayExpr, rightop);
 
@@ -1704,6 +1704,16 @@ match_clause_to_partition_key(RelOptInfo *rel,
 
 			elem_exprs = arrexpr->elements;
 		}
+		else
+		{
+			/*
+			 * Ignore all other clause types.  It could be possible here
+			 * to reach this code path with a type coercion from an
+			 * array type to another with ArrayCoerceExpr which depends on
+			 * per-element execution for the conversion.
+			 */
+			return PARTCLAUSE_UNSUPPORTED;
+		}
 
 		/*
 		 * Now generate a list of clauses, one for each array element, of the
diff --git a/src/test/regress/expected/partition_prune.out b/src/test/regress/expected/partition_prune.out
index e0cc5f3393..86dcd62d55 100644
--- a/src/test/regress/expected/partition_prune.out
+++ b/src/test/regress/expected/partition_prune.out
@@ -1073,6 +1073,48 @@ explain (costs off) select * from boolpart where a is not unknown;
          Filter: (a IS NOT UNKNOWN)
 (7 rows)
 
+-- type coercion from one array type to another, no pruning
+create table coercepart (a varchar) partition by list (a);
+create table coercepart_ab partition of coercepart for values in ('ab');
+create table coercepart_cd partition of coercepart for values in ('cd');
+create table coercepart_ef_gh partition of coercepart for values in ('ef', 'gh');
+explain (costs off) select * from coercepart where a in ('ab', to_char(125, '999'));
+                                                          QUERY PLAN                                                          
+------------------------------------------------------------------------------------------------------------------------------
+ Append
+   ->  Seq Scan on coercepart_ab
+         Filter: ((a)::text = ANY ((ARRAY['ab'::character varying, (to_char(125, '999'::text))::character varying])::text[]))
+   ->  Seq Scan on coercepart_cd
+         Filter: ((a)::text = ANY ((ARRAY['ab'::character varying, (to_char(125, '999'::text))::character varying])::text[]))
+   ->  Seq Scan on coercepart_ef_gh
+         Filter: ((a)::text = ANY ((ARRAY['ab'::character varying, (to_char(125, '999'::text))::character varying])::text[]))
+(7 rows)
+
+explain (costs off) select * from coercepart where a in ('ab', NULL, to_char(125, '999'));
+                                                                      QUERY PLAN                                                                       
+-------------------------------------------------------------------------------------------------------------------------------------------------------
+ Append
+   ->  Seq Scan on coercepart_ab
+         Filter: ((a)::text = ANY ((ARRAY['ab'::character varying, NULL::character varying, (to_char(125, '999'::text))::character varying])::text[]))
+   ->  Seq Scan on coercepart_cd
+         Filter: ((a)::text = ANY ((ARRAY['ab'::character varying, NULL::character varying, (to_char(125, '999'::text))::character varying])::text[]))
+   ->  Seq Scan on coercepart_ef_gh
+         Filter: ((a)::text = ANY ((ARRAY['ab'::character varying, NULL::character varying, (to_char(125, '999'::text))::character varying])::text[]))
+(7 rows)
+
+explain (costs off) select * from coercepart where a in ('ef', 'gh', to_char(125, '999'));
+                                                                      QUERY PLAN                                                                       
+-------------------------------------------------------------------------------------------------------------------------------------------------------
+ Append
+   ->  Seq Scan on coercepart_ab
+         Filter: ((a)::text = ANY ((ARRAY['ef'::character varying, 'gh'::character varying, (to_char(125, '999'::text))::character varying])::text[]))
+   ->  Seq Scan on coercepart_cd
+         Filter: ((a)::text = ANY ((ARRAY['ef'::character varying, 'gh'::character varying, (to_char(125, '999'::text))::character varying])::text[]))
+   ->  Seq Scan on coercepart_ef_gh
+         Filter: ((a)::text = ANY ((ARRAY['ef'::character varying, 'gh'::character varying, (to_char(125, '999'::text))::character varying])::text[]))
+(7 rows)
+
+drop table coercepart;
 --
 -- some more cases
 --
diff --git a/src/test/regress/sql/partition_prune.sql b/src/test/regress/sql/partition_prune.sql
index 6b7f57ab41..267b7a3545 100644
--- a/src/test/regress/sql/partition_prune.sql
+++ b/src/test/regress/sql/partition_prune.sql
@@ -152,6 +152,16 @@ explain (costs off) select * from boolpart where a is not true and a is not fals
 explain (costs off) select * from boolpart where a is unknown;
 explain (costs off) select * from boolpart where a is not unknown;
 
+-- type coercion from one array type to another, no pruning
+create table coercepart (a varchar) partition by list (a);
+create table coercepart_ab partition of coercepart for values in ('ab');
+create table coercepart_cd partition of coercepart for values in ('cd');
+create table coercepart_ef_gh partition of coercepart for values in ('ef', 'gh');
+explain (costs off) select * from coercepart where a in ('ab', to_char(125, '999'));
+explain (costs off) select * from coercepart where a in ('ab', NULL, to_char(125, '999'));
+explain (costs off) select * from coercepart where a in ('ef', 'gh', to_char(125, '999'));
+drop table coercepart;
+
 --
 -- some more cases
 --