Merge maint1.mysql.com:/data/localhome/cmiller/bug15583/my50-bug15583

into  maint1.mysql.com:/data/localhome/cmiller/bug15583/my51-bug15583


mysql-test/r/type_bit.result:
  Auto merged
sql/item_strfunc.cc:
  Auto merged

1 files changed, 24 insertions, 8 deletions

diff --git a/sql/item_strfunc.cc b/sql/item_strfunc.cc
index dee7f408733..2bfe7e8e81b 100644
--- a/sql/item_strfunc.cc
+++ b/sql/item_strfunc.cc
@@ -2359,17 +2359,33 @@ String *Item_func_conv::val_str(String *str)
       abs(to_base) > 36 || abs(to_base) < 2 ||
       abs(from_base) > 36 || abs(from_base) < 2 || !(res->length()))
   {
-    null_value=1;
-    return 0;
+    null_value= 1;
+    return NULL;
   }
-  null_value=0;
+  null_value= 0;
   unsigned_flag= !(from_base < 0);
-  if (from_base < 0)
-    dec= my_strntoll(res->charset(),res->ptr(),res->length(),-from_base,&endptr,&err);
+
+  if (args[0]->field_type() == MYSQL_TYPE_BIT) 
+  {
+    /* 
+     Special case: The string representation of BIT doesn't resemble the
+     decimal representation, so we shouldn't change it to string and then to
+     decimal. 
+    */
+    dec= args[0]->val_int();
+  }
   else
-    dec= (longlong) my_strntoull(res->charset(),res->ptr(),res->length(),from_base,&endptr,&err);
-  ptr= longlong2str(dec,ans,to_base);
-  if (str->copy(ans,(uint32) (ptr-ans), default_charset()))
+  {
+    if (from_base < 0)
+      dec= my_strntoll(res->charset(), res->ptr(), res->length(),
+                       -from_base, &endptr, &err);
+    else
+      dec= (longlong) my_strntoull(res->charset(), res->ptr(), res->length(),
+                                   from_base, &endptr, &err);
+  }
+
+  ptr= longlong2str(dec, ans, to_base);
+  if (str->copy(ans, (uint32) (ptr-ans), default_charset()))
     return &my_empty_string;
   return str;
 }