These issues were found by Coverity static analysis tool, for more info see messages by particular fixes (messages belong to 5.1.61). Filed upstream at http://bugs.mysql.com/bug.php?id=64631 Error: BUFFER_SIZE_WARNING: /builddir/build/BUILD/mysql-5.1.61/sql/sql_prepare.cc:2749: buffer_size_warning: Calling strncpy with a maximum size argument of 512 bytes on destination array "this->stmt->last_error" of size 512 bytes might leave the destination string unterminated. diff -up mysql-5.6.10/sql/sql_prepare.cc.orig mysql-5.6.10/sql/sql_prepare.cc --- mysql-5.6.10/sql/sql_prepare.cc.orig 2013-01-22 17:54:50.000000000 +0100 +++ mysql-5.6.10/sql/sql_prepare.cc 2013-02-19 15:50:53.257150632 +0100 @@ -2956,7 +2956,7 @@ void mysql_stmt_get_longdata(THD *thd, c { stmt->state= Query_arena::STMT_ERROR; stmt->last_errno= thd->get_stmt_da()->sql_errno(); - strncpy(stmt->last_error, thd->get_stmt_da()->message(), MYSQL_ERRMSG_SIZE); + strncpy(stmt->last_error, thd->get_stmt_da()->message(), sizeof(stmt->last_error)-1); } thd->set_stmt_da(save_stmt_da); Error: STRING_OVERFLOW: /builddir/build/BUILD/mysql-5.1.61/sql/sql_trigger.cc:2194: fixed_size_dest: You might overrun the 512 byte fixed-size string "this->m_parse_error_message" by copying "error_message" without checking the length. /builddir/build/BUILD/mysql-5.1.61/sql/sql_trigger.cc:2194: parameter_as_source: Note: This defect has an elevated risk because the source argument is a parameter of the current function. diff -up mysql-5.6.10/sql/sql_trigger.cc.orig mysql-5.6.10/sql/sql_trigger.cc --- mysql-5.6.10/sql/sql_trigger.cc.orig 2013-01-22 17:54:50.000000000 +0100 +++ mysql-5.6.10/sql/sql_trigger.cc 2013-02-19 16:01:10.605885117 +0100 @@ -2303,7 +2303,7 @@ void Table_triggers_list::mark_fields_us void Table_triggers_list::set_parse_error_message(char *error_message) { m_has_unparseable_trigger= true; - strcpy(m_parse_error_message, error_message); + strncpy(m_parse_error_message, error_message, sizeof(m_parse_error_message)-1); }