Memory leak in QTestLib

I am trying to add a memory leak detection feature to QTestLib, so we can find out memory leak during test execution.

when i am using my updated qtestlib to run several test cases under tests/auto, i found memory leaks in some of them.

Below is a memory leak in QTestLib component:
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memory leak failure in tests/auto/qsqldatabase, test case precisionPolicy()
FAIL! : tst_QSqlDatabase::precisionPolicy(0_QSQLITE@/tmp/foo.db) memory leaked (36) bytes

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MemoryLeakAnalysis:
->tst_qsqldatabase.cpp, line 1732 (QEXPECT_FAIL("QOCI", "Oracle fails here, to retrieve next", Continue)
->qtestcase.cpp, line 1812 (return QTestResult::expectFail(dataIndex, qstrdup(comment), mode, file, line)
->qtestresult.cpp, line 195
if (!isExpectFailData(dataIndex))
return true; // we don't care

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MemoryLeak Place: src/testlib/qtestresult, line 195
MemoryLeak Scenario: Since the comment input argument is a newly created string on heap using qstrdup, it should be deleted before return at line 195.

Although I am testing on 4.6.3 branch, this error still exists on the trunk