MySQL Bugs: #94743: Exception while closing mysql connection through C Connector

Bug #94743	Exception while closing mysql connection through C Connector
Submitted:	22 Mar 2019 7:24	Modified:	22 Apr 2019 15:14
Reporter:	Bharathkumar Hegde	Email Updates:
Status:	No Feedback	Impact on me:	None
Category:	MySQL Server: C API (client library)	Severity:	S2 (Serious)
Version:	latest	OS:	Windows
Assigned to:		CPU Architecture:	Any
Tags:	C_API, heap_corruption, MySQL, windows

Description:
I am using C API library fro my windows application. Query execution completes, but running into an exception while closing mysql connection.

Here is the dump stack 

>	libmysql.dll!MEM_ROOT::Clear() Line 143	C++
 	libmysql.dll!free_root(MEM_ROOT * root, int flags) Line 262	C++
 	libmysql.dll!free_old_query(MYSQL * mysql) Line 1286	C++
 	libmysql.dll!mysql_close(MYSQL * mysql) Line 5215	C++
 	MySqlConnector.exe!MySqlInterface::~MySqlInterface() Line 352	C++
 	MySqlConnector.exe!main(int argc, char * * argv) Line 62	C++
 	[External Code]	

Using libmysql.dll built from latest code available in git. 

Application is throwing exception with c library packaged with MySQL 8.0.13 in windows.

How to repeat:
Build an application with c API, which initiates mysql connection, runs a query and closes the connection using 'mysql_close' function.

Suggested fix:
Find out the root cause for this heap corruption and fix it.

Thank you for the bug report. Please specific the exactly version, currently the client library for Windows is the one shipped together with server in lib folde. Also attach a test case client version. Thanks in advance.

No feedback was provided for this bug for over a month, so it is
being suspended automatically. If you are able to provide the
information that was originally requested, please do so and change
the status of the bug back to "Open".