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This crash occured if the same debug trace file was closed twice, leading to the same memory being free'd twice. This could occur if the "debug" server system variable refered to the same trace file in both global and session scope. Example of an order of events that would lead to a crash: 1) Enable debug tracing to a trace file (global scope) 2) Enable debug tracing to the same trace file (session scope) 3) Reset debug settings (global scope) 4) Reset debug settings (session scope) This caused a crash because the trace file was, by mistake, closed in 3), leading to the same memory being free'd twice when the file was closed again in 4). Internally, the debug settings are stored in a stack, with session settings (if any) on top and the global settings below. Each connection has its own stack. When a set of settings is changed, it must be determined if its debug trace file is to be closed. Before, this was done by only checking below on the settings stack. So if the global settings were changed, an existing debug trace file reference in session settings would be missed. This caused the file to be closed even if it was in use, leading to a crash later when it was closed again. This patch fixes the problem by preventing the trace file from being shared between global and session settings. If session debug settings are set without specifying a new trace file, stderr is used for output. This is a change in behaviour and should be reflected in the documentation. Test case added to variables.test.
This directory contains a test suite for the MySQL daemon. To run the currently existing test cases, simply execute ./mysql-test-run in this directory. It will fire up the newly built mysqld and test it. Note that you do not have to have to do "make install", and you could actually have a co-existing MySQL installation. The tests will not conflict with it. All tests must pass. If one or more of them fail on your system, please read the following manual section for instructions on how to report the problem: http://dev.mysql.com/doc/mysql/en/mysql-test-suite.html If you want to use an already running MySQL server for specific tests, use the --extern option to mysql-test-run. Please note that in this mode, the test suite expects you to provide the names of the tests to run. For example, here is the command to run the "alias" and "analyze" tests with an external server: mysql-test-run --extern alias analyze To match your setup, you might also need to provide --socket, --user, and other relevant options. With no test cases named on the command line, mysql-test-run falls back to the normal "non-extern" behavior. The reason for this is that some tests cannot run with an external server. You can create your own test cases. To create a test case, create a new file in the t subdirectory using a text editor. The file should have a .test extension. For example: xemacs t/test_case_name.test In the file, put a set of SQL statements that create some tables, load test data, and run some queries to manipulate it. We would appreciate it if you name your test tables t1, t2, t3 ... (to not conflict too much with existing tables). Your test should begin by dropping the tables you are going to create and end by dropping them again. This ensures that you can run the test over and over again. If you are using mysqltest commands (like result file names) in your test case, you should create the result file as follows: mysql-test-run --record test_case_name or mysqltest --record < t/test_case_name.test If you only have a simple test cases consisting of SQL statements and comments, you can create the test case in one of the following ways: mysql-test-run --record test_case_name mysql test < t/test_case_name.test > r/test_case_name.result mysqltest --record --record-file=r/test_case_name.result < t/test_case_name.test When this is done, take a look at r/test_case_name.result - If the result is incorrect, you have found a bug. In this case, you should edit the test result to the correct results so that we can verify that the bug is corrected in future releases. To submit your test case, put your .test file and .result file(s) into a tar.gz archive, add a README that explains the problem, ftp the archive to ftp://support.mysql.com/pub/mysql/secret/ and send a mail to bugs@lists.mysql.com