3 files changed, 44 insertions, 1 deletions
diff --git a/src/backend/access/brin/brin_minmax_multi.c b/src/backend/access/brin/brin_minmax_multi.c
index 8c72a0a0366..7e63dda14f4 100644
--- a/src/backend/access/brin/brin_minmax_multi.c
+++ b/src/backend/access/brin/brin_minmax_multi.c
@@ -2081,13 +2081,18 @@ brin_minmax_multi_distance_uuid(PG_FUNCTION_ARGS)
 Datum
 brin_minmax_multi_distance_date(PG_FUNCTION_ARGS)
 {
+	float8		delta = 0;
 	DateADT		dateVal1 = PG_GETARG_DATEADT(0);
 	DateADT		dateVal2 = PG_GETARG_DATEADT(1);
 
 	if (DATE_NOT_FINITE(dateVal1) || DATE_NOT_FINITE(dateVal2))
 		PG_RETURN_FLOAT8(0);
 
-	PG_RETURN_FLOAT8(dateVal1 - dateVal2);
+	delta = (float8) dateVal2 - (float8) dateVal1;
+
+	Assert(delta >= 0);
+
+	PG_RETURN_FLOAT8(delta);
 }
 
 /*
diff --git a/src/test/regress/expected/brin_multi.out b/src/test/regress/expected/brin_multi.out
index c18d9764c1c..465f93f55f1 100644
--- a/src/test/regress/expected/brin_multi.out
+++ b/src/test/regress/expected/brin_multi.out
@@ -836,5 +836,25 @@ SELECT '294276-12-01 00:00:01'::timestamptz + (i || ' seconds')::interval
   FROM generate_series(1,30) s(i);
 CREATE INDEX ON brin_timestamp_test USING brin (a timestamptz_minmax_multi_ops) WITH (pages_per_range=1);
 DROP TABLE brin_timestamp_test;
+-- test overflows during CREATE INDEX with extreme date values
+CREATE TABLE brin_date_test(a DATE);
+-- insert values close to date minimum
+INSERT INTO brin_date_test SELECT '4713-01-01 BC'::date + i FROM generate_series(1, 30) s(i);
+-- insert values close to date minimum
+INSERT INTO brin_date_test SELECT '5874897-12-01'::date + i FROM generate_series(1, 30) s(i);
+CREATE INDEX ON brin_date_test USING brin (a date_minmax_multi_ops) WITH (pages_per_range=1);
+SET enable_seqscan = off;
+-- make sure the ranges were built correctly and 2023-01-01 eliminates all
+EXPLAIN (ANALYZE, TIMING OFF, COSTS OFF, SUMMARY OFF)
+SELECT * FROM brin_date_test WHERE a = '2023-01-01'::date;
+                               QUERY PLAN                                
+-------------------------------------------------------------------------
+ Bitmap Heap Scan on brin_date_test (actual rows=0 loops=1)
+   Recheck Cond: (a = '2023-01-01'::date)
+   ->  Bitmap Index Scan on brin_date_test_a_idx (actual rows=0 loops=1)
+         Index Cond: (a = '2023-01-01'::date)
+(4 rows)
+
+DROP TABLE brin_date_test;
 RESET enable_seqscan;
 RESET datestyle;
diff --git a/src/test/regress/sql/brin_multi.sql b/src/test/regress/sql/brin_multi.sql
index 847bb5aa016..88ccf0bc654 100644
--- a/src/test/regress/sql/brin_multi.sql
+++ b/src/test/regress/sql/brin_multi.sql
@@ -605,5 +605,23 @@ SELECT '294276-12-01 00:00:01'::timestamptz + (i || ' seconds')::interval
 CREATE INDEX ON brin_timestamp_test USING brin (a timestamptz_minmax_multi_ops) WITH (pages_per_range=1);
 DROP TABLE brin_timestamp_test;
 
+-- test overflows during CREATE INDEX with extreme date values
+CREATE TABLE brin_date_test(a DATE);
+
+-- insert values close to date minimum
+INSERT INTO brin_date_test SELECT '4713-01-01 BC'::date + i FROM generate_series(1, 30) s(i);
+
+-- insert values close to date minimum
+INSERT INTO brin_date_test SELECT '5874897-12-01'::date + i FROM generate_series(1, 30) s(i);
+
+CREATE INDEX ON brin_date_test USING brin (a date_minmax_multi_ops) WITH (pages_per_range=1);
+
+SET enable_seqscan = off;
+
+-- make sure the ranges were built correctly and 2023-01-01 eliminates all
+EXPLAIN (ANALYZE, TIMING OFF, COSTS OFF, SUMMARY OFF)
+SELECT * FROM brin_date_test WHERE a = '2023-01-01'::date;
+
+DROP TABLE brin_date_test;
 RESET enable_seqscan;
 RESET datestyle;