This is an automated cherry-pick of pingcap#46278

Signed-off-by: ti-chi-bot <ti-community-prow-bot@tidb.io>

planner/core/plan_cache.go

@@ -347,7 +347,7 @@ func RebuildPlan4CachedPlan(p Plan) (ok bool) {
 	sc.InPreparedPlanBuilding = true
 	defer func() { sc.InPreparedPlanBuilding = false }()
 	if err := rebuildRange(p); err != nil {
-		// TODO: log or warn this error.
+		sc.AppendWarning(errors.Errorf("skip plan-cache: plan rebuild failed, %s", err.Error()))
 		return false // fail to rebuild ranges
 	}
 	if !sc.UseCache {

planner/core/plan_cache_test.go

@@ -2367,6 +2367,61 @@ func TestIssue45253(t *testing.T) {
 	tk.MustQuery(`SELECT c1 FROM t1 WHERE TO_BASE64('')`).Check(testkit.Rows())
 }
 
+<<<<<<< HEAD
+=======
+func TestIssue45378(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test")
+	tk.MustExec(`set tidb_enable_non_prepared_plan_cache=1`)
+	tk.MustExec(`CREATE TABLE t1(c1 INT)`)
+	tk.MustExec(`INSERT INTO t1 VALUES (1)`)
+
+	tk.MustQuery(`SELECT c1 FROM t1 WHERE UNHEX(2038330881)`).Check(testkit.Rows("1"))
+	tk.MustQuery(`SELECT c1 FROM t1 WHERE UNHEX(2038330881)`).Check(testkit.Rows("1"))
+	tk.MustQuery(`select @@last_plan_from_cache`).Check(testkit.Rows("1"))
+}
+
+func TestIssue46159(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test")
+	tk.MustExec(`create table t (a varchar(10), key(a(5)))`)
+	tk.MustExec(`prepare st from 'select a from t use index(a) where a=?'`)
+	tk.MustExec(`set @a='a'`)
+	tk.MustQuery(`execute st using @a`).Check(testkit.Rows())
+	tk.MustQuery(`execute st using @a`).Check(testkit.Rows())
+	tk.MustQuery(`show warnings`).Check(testkit.Rows("Warning 1105 skip plan-cache: plan rebuild failed, rebuild to get an unsafe range"))
+}
+
+func TestBuiltinFuncFlen(t *testing.T) {
+	// same as TestIssue45378 and TestIssue45253
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test")
+	tk.MustExec(`CREATE TABLE t1(c1 INT)`)
+	tk.MustExec(`INSERT INTO t1 VALUES (1)`)
+
+	funcs := []string{ast.Abs, ast.Acos, ast.Asin, ast.Atan, ast.Ceil, ast.Ceiling, ast.Cos,
+		ast.CRC32, ast.Degrees, ast.Floor, ast.Ln, ast.Log, ast.Log2, ast.Log10, ast.Unhex,
+		ast.Radians, ast.Rand, ast.Round, ast.Sign, ast.Sin, ast.Sqrt, ast.Tan, ast.SM3,
+		ast.Quote, ast.RTrim, ast.ToBase64, ast.Trim, ast.Upper, ast.Ucase, ast.Hex,
+		ast.BitLength, ast.CharLength, ast.Compress, ast.MD5, ast.SHA1, ast.SHA}
+	args := []string{"2038330881", "'2038330881'", "'牵'", "-1", "''", "0"}
+
+	for _, f := range funcs {
+		for _, a := range args {
+			q := fmt.Sprintf("SELECT c1 from t1 where %s(%s)", f, a)
+			tk.MustExec(`set tidb_enable_non_prepared_plan_cache=1`)
+			r1 := tk.MustQuery(q)
+			tk.MustExec(`set tidb_enable_non_prepared_plan_cache=0`)
+			r2 := tk.MustQuery(q)
+			r1.Sort().Check(r2.Sort().Rows())
+		}
+	}
+}
+
+>>>>>>> 94cfa8b0713 (planner: output a warning if plan rebuilding fails when reusing a cached plan (#46278))
 func TestNonPreparedPlanCacheBuiltinFuncs(t *testing.T) {
 	store := testkit.CreateMockStore(t)
 	tk := testkit.NewTestKit(t, store)