bug#42977

compilation warning fixed

sql/log_event.cc

@@ -7764,7 +7764,7 @@ Table_map_log_event::Table_map_log_event(THD *thd, TABLE *tbl, ulong tid,
   m_data_size+= m_dblen + 2;	// Include length and terminating \0
   m_data_size+= m_tbllen + 2;	// Include length and terminating \0
   cbuf_end= net_store_length(cbuf, (size_t) m_colcnt);
-  DBUG_ASSERT((cbuf_end - cbuf) <= sizeof(cbuf));
+  DBUG_ASSERT(static_cast<size_t>(cbuf_end - cbuf) <= sizeof(cbuf));
   m_data_size+= (cbuf_end - cbuf) + m_colcnt;	// COLCNT and column types
 
   /* If malloc fails, caught in is_valid() */