Bug #42787 Segmentation Fault using storein with SSQLS set and exceptions disabled
Submitted: 12 Feb 2009 12:04 Modified: 31 Jul 2009 9:20
Reporter: juan carlos Email Updates:
Status: Verified Impact on me:
Category:MySQL++ Severity:S1 (Critical)
Version:mysql++-3.0.9 OS:Linux (Fedora Core 10, Debian Etch, Debian SID)
Assigned to: CPU Architecture:Any
Tags: segmentation fault, SET, SSQLS, storein

[12 Feb 2009 12:04] juan carlos
When using mysql++ libray, using Connection with no exceptions, and trying to get a SSQLS set from a mysql server, but passing a wrong table name, you get a Segmentation Fault.

Following is an example of execution using mysql++ 3.0.8. Similar results are obtained with mysql++ 3.0.9:

(gdb) run EJEMPLO localhost root ""
Starting program: /home/jk/kk/sample EJEMPLO localhost root ""
[Thread debugging using libthread_db enabled]
[New Thread 0xb7fe3730 (LWP 2999)]
There are rows in Table_A

Program received signal SIGSEGV, Segmentation fault.
mysql_fetch_row (res=0x0) at client.c:2917
2917	  if (!res->data)
(gdb) bt
#0  mysql_fetch_row (res=0x0) at client.c:2917
#1  0x00139380 in mysqlpp::DBDriver::fetch_row () at lib/dbdriver.h:209
#2  mysqlpp::UseQueryResult::fetch_raw_row (this=0xbffff1a0) at lib/result.cpp:205
#3  0x0804e45f in mysqlpp::Query::storein_set<std::set<stock, std::less<stock>, std::allocator<stock> > > ()
#4  0x0804e615 in mysqlpp::Query::storein<stock> ()
#5  0x0804e672 in mysqlpp::Query::storein<std::set<stock, std::less<stock>, std::allocator<stock> > > ()
#6  0x0804af24 in main ()

How to repeat:
Use MySQL++ 3.0.9. and do not use exceptions. 

Test the following code. You should create a table named Table_A with two fields, item CHAR and num BIGINT. Run the program with 4 arguments: database, server, user and password.

#include <mysql++.h>
#include <ssqls.h>

using namespace std;

	mysqlpp::sql_char, item,
	mysqlpp::sql_bigint, num);

int main (int argc, char *argv[])
	const char *db=0, *server=0, *user=0, *pass="";
	if(argc != 5) {
		cerr << "Bad args" << endl;
		return 1;
	//Establish the connection to the database server, NO EXCEPTIONS
	mysqlpp::Connection con(false);
	if(!con.connect(db, server, user, pass)) {
		cerr << "Connection error: " << con.error() << endl;

	//Create and insert a stock object
	stock row("Hot Dogs",100);
	mysqlpp::Query query=con.query();

	//Get all the rows in the table
	query << "select * from Table_A";
	set<stock> res1;
	query.storein(res1); //---OK---
	if(res1.size() > 0) cout << "There are rows in Table_A" << endl;

	//Get all rows in a table that doesn't exist
	query << "select * from NonExistentTable";
	set<stock> res2;
	query.storein(res2); //--- Segmentation fault ---
	if(res2.size() > 0) cout << "There are rows in NonExistentTable" << endl;

	return 0;

Suggested fix:
In lib/query.h file, there is no check for the return value from "use" method in storein_set and storein_sequence methods:

    UseQueryResult result =use(s);
    while (1) {
        MYSQL_ROW d=result.fetch_raw_row();

If the query is wrong, result is NULL and SIGSEGV is signaled.

The simplest fix could be the following -in storein_set and storein_sequence-:

    UseQueryResult result =use(s);
    if (result)
        while (1) {
            MYSQL_ROW d=result.fetch_raw_row();

But maybe some other lines inside the while loop could be revised, similar to the code for "store_if" method in lib/query.h.
[10 Jun 2009 23:22] Hrishikesh Mehendale
vote +1 on Ubuntu 9.04/x86_64:

storein(vector) / storein_sequence(vector) also SIGSEGVs if the table in question does not exist.
[11 Jun 2009 0:51] Hrishikesh Mehendale
+1 more -- if the table doesn't exist, it doesn't matter whether you're using exceptions or not. You'll still get SEGV'd (I just ran into this issue).
[31 Jul 2009 9:20] Sveta Smirnova
Thank you for the report.

Verified as described.
[18 Sep 2010 20:48] Simon Pickles
Error experienced with simple typo in SQL query on Ubuntu 10.04.

Any known workaround?