1 files changed, 57 insertions, 2 deletions
diff --git a/sql/item.cc b/sql/item.cc
index 6566f3ca533..05d4cc86f7a 100644
--- a/sql/item.cc
+++ b/sql/item.cc
@@ -5998,9 +5998,64 @@ Item *Item_int_with_ref::clone_item(THD *thd)
 }
 
 
-Item_num *Item_uint::neg(THD *thd)
+Item *Item::neg(THD *thd)
 {
-  Item_decimal *item= new (thd->mem_root) Item_decimal(thd, value, 1);
+  return new (thd->mem_root) Item_func_neg(thd, this);
+}
+
+Item *Item_int::neg(THD *thd)
+{
+  /*
+    The following if should never be true with code generated by
+    our parser as LONGLONG_MIN values will be stored as decimal.
+    The code is here in case someone generates an int from inside
+    MariaDB
+  */
+  if (unlikely(value == LONGLONG_MIN))
+  {
+    /* Precision for int not big enough; Convert constant to decimal */
+    Item_decimal *item= new (thd->mem_root) Item_decimal(thd, value, 0);
+    return item ? item->neg(thd) : item;
+  }
+  if (value > 0)
+    max_length++;
+  else if (value < 0 && max_length)
+    max_length--;
+  value= -value;
+  name= 0;
+  return this;
+}
+
+Item *Item_decimal::neg(THD *thd)
+{
+  my_decimal_neg(&decimal_value);
+  unsigned_flag= 0;
+  name= 0;
+  max_length= my_decimal_precision_to_length_no_truncation(
+                      decimal_value.intg + decimals, decimals, unsigned_flag);
+  return this;
+}
+
+Item *Item_float::neg(THD *thd)
+{
+  if (value > 0)
+    max_length++;
+  else if (value < 0 && max_length)
+    max_length--;
+  value= -value;
+  name= presentation= 0 ;
+  return this;
+}
+
+Item *Item_uint::neg(THD *thd)
+{
+  Item_decimal *item;
+  if (((ulonglong)value) <= LONGLONG_MAX)
+    return new (thd->mem_root) Item_int(thd, -value, max_length+1);
+  if (value == LONGLONG_MIN)
+    return new (thd->mem_root) Item_int(thd, value, max_length+1);
+  if (!(item= new (thd->mem_root) Item_decimal(thd, value, 1)))
+    return 0;
   return item->neg(thd);
 }