Backport of WL #2934: Make/find library for doing float/double

                      to string conversions and vice versa" 
Initial import of the dtoa.c code and custom wrappers around it 
to allow its usage from the server code. 
 
Conversion of FLOAT/DOUBLE values to DECIMAL ones or strings 
and vice versa has been significantly reworked. As the new 
algoritms are more precise than the older ones, results of such 
conversions may not always match those obtained from older 
server versions. This in turn may break compatibility for some 
applications. 
 
This patch also fixes the following bugs: 
- bug #12860 "Difference in zero padding of exponent between 
Unix and Windows" 
- bug #21497 "DOUBLE truncated to unusable value" 
- bug #26788 "mysqld (debug) aborts when inserting specific 
numbers into char fields" 
- bug #24541 "Data truncated..." on decimal type columns 
without any good reason" 

1 files changed, 31 insertions, 39 deletions

diff --git a/mysql-test/r/insert.result b/mysql-test/r/insert.result
index 36d2b9ef348..b322c5da73a 100644
--- a/mysql-test/r/insert.result
+++ b/mysql-test/r/insert.result
@@ -175,12 +175,12 @@ Warning	1264	Out of range value for column 'f_float_3_1_u' at row 1
 select * from t1 where number =last_insert_id();
 number	4
 original_value	1e+1111111111a
-f_double	1.79769313486232e+308
-f_float	3.40282e+38
+f_double	1.7976931348623157e308
+f_float	3.40282e38
 f_double_7_2	99999.99
 f_float_4_3	9.999
-f_double_u	1.79769313486232e+308
-f_float_u	3.40282e+38
+f_double_u	1.7976931348623157e308
+f_float_u	3.40282e38
 f_double_15_1_u	99999999999999.9
 f_float_3_1_u	99.9
 set @value= "-1e+1111111111a";
@@ -204,8 +204,8 @@ Warning	1264	Out of range value for column 'f_float_3_1_u' at row 1
 select * from t1 where number =last_insert_id();
 number	5
 original_value	-1e+1111111111a
-f_double	-1.79769313486232e+308
-f_float	-3.40282e+38
+f_double	-1.7976931348623157e308
+f_float	-3.40282e38
 f_double_7_2	-99999.99
 f_float_4_3	-9.999
 f_double_u	0
@@ -227,13 +227,13 @@ Warning	1264	Out of range value for column 'f_double_15_1_u' at row 1
 Warning	1264	Out of range value for column 'f_float_3_1_u' at row 1
 select * from t1 where number =last_insert_id();
 number	6
-original_value	1e+111
-f_double	1e+111
-f_float	3.40282e+38
+original_value	1e111
+f_double	1e111
+f_float	3.40282e38
 f_double_7_2	99999.99
 f_float_4_3	9.999
-f_double_u	1e+111
-f_float_u	3.40282e+38
+f_double_u	1e111
+f_float_u	3.40282e38
 f_double_15_1_u	99999999999999.9
 f_float_3_1_u	99.9
 set @value= -1e+111;
@@ -248,9 +248,9 @@ Warning	1264	Out of range value for column 'f_double_15_1_u' at row 1
 Warning	1264	Out of range value for column 'f_float_3_1_u' at row 1
 select * from t1 where number =last_insert_id();
 number	7
-original_value	-1e+111
-f_double	-1e+111
-f_float	-3.40282e+38
+original_value	-1e111
+f_double	-1e111
+f_float	-3.40282e38
 f_double_7_2	-99999.99
 f_float_4_3	-9.999
 f_double_u	0
@@ -524,42 +524,36 @@ INSERT INTO t1(a,b) VALUES (1.25e-175, 1.25e-175);
 INSERT INTO t1(a,c) VALUES (1.225e+0, 1.225e+0);
 INSERT INTO t1(a,c) VALUES (1.37e+0, 1.37e+0);
 INSERT INTO t1(a,c) VALUES (-1.37e+0, -1.37e+0);
-Warnings:
-Warning	1265	Data truncated for column 'c' at row 1
 INSERT INTO t1(a,c) VALUES (1.87e-3, 1.87e-3);
 Warnings:
 Warning	1265	Data truncated for column 'c' at row 1
 INSERT INTO t1(a,c) VALUES (-1.87e-2, -1.87e-2);
-Warnings:
-Warning	1265	Data truncated for column 'c' at row 1
 INSERT INTO t1(a,c) VALUES (5000e+0, 5000e+0);
 INSERT INTO t1(a,c) VALUES (-5000e+0, -5000e+0);
-Warnings:
-Warning	1265	Data truncated for column 'c' at row 1
 SELECT * FROM t1;
 a	b	c
 9.999999	10	10
-1.225e-05	1.2e-05	1e-0
-0.0001225	0.00012	NULL
+0.00001225	1.22e-5	1e-5
+0.0001225	1.22e-4	NULL
 0.1225	0.1225	NULL
 0.1225877	0.12259	NULL
 12.25	12.25	NULL
 12.25	12.25	12.2
 122500	122500	NULL
-12250000000	1.2e+10	NULL
-1.225e+15	1.2e+15	NULL
+12250000000	1.22e10	NULL
+1.225e15	1.22e15	NULL
 5000000	5000000	NULL
-1.25e+78	1.2e+78	NULL
+1.25e78	1.25e78	NULL
 1.25e-94	1.2e-94	NULL
-1.25e+203	1e+203	NULL
+1.25e203	1.2e203	NULL
 1.25e-175	1e-175	NULL
 1.225	NULL	1.23
 1.37	NULL	1.37
--1.37	NULL	-1.3
-0.00187	NULL	0.00
--0.0187	NULL	-0.0
+-1.37	NULL	-1.4
+0.00187	NULL	2e-3
+-0.0187	NULL	0
 5000	NULL	5000
--5000	NULL	-500
+-5000	NULL	-5e3
 DROP TABLE t1;
 CREATE TABLE t1 (
 a char(20) NOT NULL,
@@ -586,32 +580,30 @@ INSERT INTO t1(a,c) VALUES (1.37e+0, 1.37e+0);
 INSERT INTO t1(a,c) VALUES (-1.37e+0, -1.37e+0);
 INSERT INTO t1(a,c) VALUES (1.87e-3, 1.87e-3);
 INSERT INTO t1(a,c) VALUES (-1.87e-2, -1.87e-2);
-Warnings:
-Warning	1265	Data truncated for column 'c' at row 1
 INSERT INTO t1(a,c) VALUES (5000e+0, 5000e+0);
 INSERT INTO t1(a,c) VALUES (-5000e+0, -5000e+0);
 SELECT * FROM t1;
 a	b	c
 9.999999	10	9.999
-1.225e-05	1.2e-05	1e-05
-0.0001225	0.00012	NULL
+0.00001225	1.22e-5	1e-5
+0.0001225	1.22e-4	NULL
 0.1225	0.1225	NULL
 0.1225877	0.12259	NULL
 12.25	12.25	NULL
 12.25	12.25	12.25
 122500	122500	NULL
-12250000000	1.2e+10	NULL
-1.225e+15	1.2e+15	NULL
+12250000000	1.22e10	NULL
+1.225e15	1.22e15	NULL
 5000000	5000000	NULL
-1.25e+78	1.2e+78	NULL
+1.25e78	1.25e78	NULL
 1.25e-94	1.2e-94	NULL
-1.25e+203	1e+203	NULL
+1.25e203	1.2e203	NULL
 1.25e-175	1e-175	NULL
 1.225	NULL	1.225
 1.37	NULL	1.37
 -1.37	NULL	-1.37
 0.00187	NULL	0.002
--0.0187	NULL	-0.01
+-0.0187	NULL	-0.02
 5000	NULL	5000
 -5000	NULL	-5000
 DROP TABLE t1;