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POSegmentation fault when connecting to MySQL
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copied!<p>I have this code in a big project that makes a connection to a MySQL database, and does not work:</p> <pre><code>boost::shared_ptr<sql::Connection> connection; sql::Driver *driver = get_driver_instance(); assert(driver != 0); std::string server = "servname", user = "pietro", password = "abc"; try { connection.reset(driver->connect(server, user, password)); assert(connection != 0); if(connection->isClosed() == false) // <-- segmentation fault { } } </code></pre> <p>I get a segmentation fault where indicated (all parameters are valid).<br> However, this same code works in a test project. </p> <p>Going into the <code>sql::Connection::isClosed()</code> member function with a debugger, I obtain no information about the possible cause; here is where I get: </p> <blockquote> <p>mysql-connector-c++-1.0.5/driver/mysql_connection.cpp - line 430</p> </blockquote> <pre><code>/* {{{ MySQL_Connection::checkClosed() -I- */ void MySQL_Connection::checkClosed() { CPP_ENTER_WL(intern->logger, "MySQL_Connection::checkClosed"); if (!intern->is_valid) { throw sql::SQLException("Connection has been closed"); } } </code></pre> <p>This <code>checkClosed()</code> function is successfully executed seven times from <code>connection.reset()</code> just before. The value of the "<code>intern</code>" pointer does not change and is not null at this stage. </p> <p>When I check if the connection is closed, the <code>checkClosed()</code> function is run again. Now the "<code>intern</code>" pointer value is 0x8, a location I cannot access. </p> <p>Here I get a <code>SIGSEGV</code>, segmentation fault.</p> <p>Let me know if you would like the disassembled code...</p> <p><em>Platform:</em><br> MySQL 5.x<br> MySQL Connector/C++ 1.0.5<br> Linux - OpenSuse 11.4 </p> <hr> <p>P.S.: I noticed that all the <code>shared_ptr</code>'s member functions work as expected: </p> <pre><code>connection.get(); // = 0x8fb4a0 connection.use_count(); // = 1 connection.unique(); // = 1 </code></pre> <p>while all the calls done on the pointed object cause the segmentation fault (SIGABRT): </p> <pre><code>connection->getClientInfo(); connection->isClosed(); </code></pre>

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