From 71a7b79bcbfe90c3118e3d4379ad734dc72c9f39 Mon Sep 17 00:00:00 2001
From: Monty <monty@mariadb.org>
Date: Fri, 25 Sep 2020 13:38:48 +0300
Subject: [PATCH] Added asssert to init_of_queries() to make it more safe

Part of review of 10.4 code by Sergei.

Other things:

- Changed return type if is_active() from my_bool to bool as this is
  only used by C++ code.
---
 sql/sql_class.cc | 1 +
 sql/sql_class.h  | 6 +++++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/sql/sql_class.cc b/sql/sql_class.cc
index 4986889b3c8..e57196ee056 100644
--- a/sql/sql_class.cc
+++ b/sql/sql_class.cc
@@ -1386,6 +1386,7 @@ void THD::init_for_queries()
     We don't need to call ha_enable_transaction() as we can't have
     any active transactions that has to be committed
   */
+  DBUG_ASSERT(transaction.is_empty());
   transaction.on= TRUE;
 
   reset_root_defaults(mem_root, variables.query_alloc_block_size,
diff --git a/sql/sql_class.h b/sql/sql_class.h
index 0c2d03a516a..64cd1ed6ba3 100644
--- a/sql/sql_class.h
+++ b/sql/sql_class.h
@@ -2630,10 +2630,14 @@ public:
       free_root(&mem_root,MYF(MY_KEEP_PREALLOC));
       DBUG_VOID_RETURN;
     }
-    my_bool is_active()
+    bool is_active()
     {
       return (all.ha_list != NULL);
     }
+    bool is_empty()
+    {
+      return all.is_empty() && stmt.is_empty();
+    }
     st_transactions()
     {
       bzero((char*)this, sizeof(*this));