- Renaming variables so that they don't shadow others (After this patch one can compile with -Wshadow and get much fewer warnings)

- Changed ER(ER_...) to ER_THD(thd, ER_...) when thd was known or if there was many calls to current_thd in the same function.
- Changed ER(ER_..) to ER_THD_OR_DEFAULT(current_thd, ER...) in some places where current_thd is not necessary defined.
- Removing calls to current_thd when we have access to thd

Part of this is optimization (not calling current_thd when not needed),
but part is bug fixing for error condition when current_thd is not defined
(For example on startup and end of mysqld)

Notable renames done as otherwise a lot of functions would have to be changed:
- In JOIN structure renamed:
   examined_rows -> join_examined_rows
   record_count -> join_record_count
- In Field, renamed new_field() to make_new_field()

Other things:
- Added DBUG_ASSERT(thd == tmp_thd) in Item_singlerow_subselect() just to be safe.
- Removed old 'tab' prefix in JOIN_TAB::save_explain_data() and use members directly
- Added 'thd' as argument to a few functions to avoid calling current_thd.

1 files changed, 13 insertions, 10 deletions

diff --git a/sql/my_decimal.cc b/sql/my_decimal.cc
index d4f1ae19bc6..5ec3fe7ff28 100644
--- a/sql/my_decimal.cc
+++ b/sql/my_decimal.cc
@@ -41,26 +41,29 @@
 
 int decimal_operation_results(int result, const char *value, const char *type)
 {
+  /* Avoid calling current_thd on default path */
+  if (likely(result == E_DEC_OK))
+    return(result);
+  
+  THD *thd= current_thd;
   switch (result) {
-  case E_DEC_OK:
-    break;
   case E_DEC_TRUNCATED:
-    push_warning_printf(current_thd, Sql_condition::WARN_LEVEL_WARN,
-			ER_DATA_TRUNCATED, ER(ER_DATA_TRUNCATED),
+    push_warning_printf(thd, Sql_condition::WARN_LEVEL_WARN,
+			ER_DATA_TRUNCATED, ER_THD(thd, ER_DATA_TRUNCATED),
 			value, type);
     break;
   case E_DEC_OVERFLOW:
-    push_warning_printf(current_thd, Sql_condition::WARN_LEVEL_WARN,
-                        ER_DATA_OVERFLOW, ER(ER_DATA_OVERFLOW),
+    push_warning_printf(thd, Sql_condition::WARN_LEVEL_WARN,
+                        ER_DATA_OVERFLOW, ER_THD(thd, ER_DATA_OVERFLOW),
 			value, type);
     break;
   case E_DEC_DIV_ZERO:
-    push_warning_printf(current_thd, Sql_condition::WARN_LEVEL_WARN,
-			ER_DIVISION_BY_ZERO, ER(ER_DIVISION_BY_ZERO));
+    push_warning_printf(thd, Sql_condition::WARN_LEVEL_WARN,
+			ER_DIVISION_BY_ZERO, ER_THD(thd, ER_DIVISION_BY_ZERO));
     break;
   case E_DEC_BAD_NUM:
-    push_warning_printf(current_thd, Sql_condition::WARN_LEVEL_WARN,
-			ER_BAD_DATA, ER(ER_BAD_DATA),
+    push_warning_printf(thd, Sql_condition::WARN_LEVEL_WARN,
+			ER_BAD_DATA, ER_THD(thd, ER_BAD_DATA),
 			value, type);
     break;
   case E_DEC_OOM: