A new assertion added to check validity of calculated selectivity values fails

DBUG_ASSERT(0.0 < sel && sel <= 1.0);

CREATE TABLE t1 (a varchar(16), b int, PRIMARY KEY(a), KEY(b));

INSERT INTO t1 VALUES

  ('USAChinese',10), ('USAEnglish',20), ('USAFrench',30);

CREATE TABLE t2 (i int);

INSERT INTO t2 VALUES

  (1),(2),(3),(4),(5),(6),(7),(8),(9),(10),(1),(2),(3),(4);

ANALYZE TABLE t1, t2;

set use_stat_tables='preferably';

set optimizer_use_condition_selectivity=3;

EXPLAIN EXTENDED

SELECT * FROM t1, t2

  WHERE  a <> 'USARussian' AND b IS NULL;

set @@optimizer_use_condition_selectivity=2;

set names utf8;

CREATE DATABASE world;

use world;

--source include/world_schema.inc

--disable_query_log

--disable_result_log

--disable_warnings

--source include/world.inc

--enable_warnings

--enable_result_log

--enable_query_log

CREATE INDEX Name ON City(Name);

CREATE INDEX CountryPopulation ON City(Country,Population);

CREATE INDEX CountryName ON City(Country,Name);

--disable_query_log

--disable_result_log

--disable_warnings

ANALYZE TABLE City;

--enable_warnings

--enable_result_log

--enable_query_log

set @@optimizer_use_condition_selectivity=2;

EXPLAIN

SELECT * FROM City WHERE Country='FIN';

DROP DATABASE world;

CREATE TABLE t1 (

  a INT,

  b INT NOT NULL,

  c char(100),

  KEY (b, c),

  KEY (b, a, c)

)

DEFAULT CHARSET = utf8;

INSERT INTO t1 VALUES 

(1,  1, 1),

(2,  2, 2),

(3,  3, 3),

(4,  4, 4),

(5,  5, 5),

(6,  6, 6),

(7,  7, 7),

(8,  8, 8),

(9,  9, 9);

INSERT INTO t1 SELECT a + 10,  b, c FROM t1;

INSERT INTO t1 SELECT a + 20,  b, c FROM t1;

INSERT INTO t1 SELECT a + 40,  b, c FROM t1;

INSERT INTO t1 SELECT a + 80,  b, c FROM t1;

INSERT INTO t1 SELECT a + 160, b, c FROM t1;

INSERT INTO t1 SELECT a + 320, b, c FROM t1;

INSERT INTO t1 SELECT a + 640, b, c FROM t1;

INSERT INTO t1 SELECT a + 1280, b, c FROM t1 LIMIT 80;

EXPLAIN

SELECT a FROM t1 WHERE b = 1 ORDER BY c DESC LIMIT 9;

SELECT a FROM t1 WHERE b = 1 ORDER BY c DESC LIMIT 9;

set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;

DROP TABLE t1;

set @@optimizer_use_condition_selectivity=2;