Fix for bug #24912 "problems with bigint in abs() ceiling() round() truncate() mod()" and a number of related problems:

- unsigned flag was not handled correctly for a number of mathematical funcions, which led to incorrect results
- passing large values as the number of decimals to ROUND() resulted in incorrect results and even server crashes in some cases
- reverted the fix and the testcase for bug #10083 as it violates the manual
- fixed some testcases which relied on broken ROUND() behavior


mysql-test/r/func_math.result:
  - Removed the testcase for bug #10083 (not a bug according to the manual)
  - Changed the testcase for bug #9837 to expect a correct ROUND() behavior
  - Added testcases for bug #24912 and all related bugs found
mysql-test/r/type_newdecimal.result:
  Fixed a truncate() testcase which relied on broken behavior
mysql-test/t/func_math.test:
  - Removed the testcase for bug #10083 (not a bug according to the manual)
  - Changed the testcase for bug #9837 to expect a correct ROUND() behavior
  - Added testcases for bug #24912 and all related bugs found
sql/item_func.cc:
  Various changes to fix bug #24912 and all related bugs found:
  - honor unsigned_flag in various Item_* functions
  - correctly handle out-of-range numbers of decimals in Item_func_round::fix_length_and_dec()
  - changed the argument specifying the number of decimals in my_double_round() from int to longlong, added a new argument to pass the 'unsigned flag'
  - changed my_double_round() to correctly handle large values passed as the 'number of decimals' argument
  - added a my_double_round() analog for BIGINT UNSIGNED arguments (my_unsigned_round())
  - fixed Item_func_round()::int_op() to not overflow even when the result is within integer range
  - fixed a bug Item_founc_round()::decimal_op() which resulted in crash when a large number of decimals was passed to my_decimal_round()
sql/item_func.h:
  Various fixed to correctly handle unsigned values.
sql/item_strfunc.cc:
  Changed the call to my_double_round() to match the new declaration.
sql/mysql_priv.h:
  Changed the declaration for my_double_round() to be able pass arbitrary integers as number of decimals (both signed and unsigned)

1 files changed, 1 insertions, 7 deletions

diff --git a/sql/item_func.h b/sql/item_func.h
index 68591f9c6f5..237a173212e 100644
--- a/sql/item_func.h
+++ b/sql/item_func.h
@@ -278,7 +278,7 @@ public:
   { max_length= 21; }
   Item_int_func(List<Item> &list) :Item_func(list) { max_length= 21; }
   Item_int_func(THD *thd, Item_int_func *item) :Item_func(thd, item) {}
-  double val_real() { DBUG_ASSERT(fixed == 1); return (double) val_int(); }
+  double val_real();
   String *val_str(String*str);
   enum Item_result result_type () const { return INT_RESULT; }
   void fix_length_and_dec() {}
@@ -303,12 +303,6 @@ class Item_func_signed :public Item_int_func
 public:
   Item_func_signed(Item *a) :Item_int_func(a) {}
   const char *func_name() const { return "cast_as_signed"; }
-  double val_real()
-  {
-    double tmp= args[0]->val_real();
-    null_value= args[0]->null_value;
-    return tmp;
-  }
   longlong val_int();
   longlong val_int_from_str(int *error);
   void fix_length_and_dec()