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Qt Creator ManualTests DebuggerLldb

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Revision as of 16:13, 11 August 2017 by Robert Loehning (talk | contribs) (Fix testing null reference)
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tests/manual/debugger/simple/simple.pro provides the needed code

Debugger lldb
Test Result Annotation
Create new project. Can you build, run and debug it? automated on Mac
Set breakpoint, press F5 to build and run debugger, verify that program stops at a breakpoint that you set:
  • in main function before program is started
  • while the program is running
  • in dynamically loaded plugins, especially in constructors
  • on a bit of code that was commented out. Make sure it is moved on debugger startup to the first line producing real code below that position and that it is hit there.
"Step into" a couple of times. Can you step into Qt source code (*.cpp file under QTDIR)?

(Mac: switch on 'Use Debug Versions of Frameworks' in run configuration. You need Qt sources.)

Test debugging helpers/python lldb: Do classes like QImage or std::string show beautiful information instead of the raw structure? automated
Step through some test* functions and check whether the displayed data looks sane
Comment out the return statement inside the following functions one by one. Check whether you'll end up with a proper stack trace & locals display.
  • testNullPointerDeref()
  • testNullReference()
  • testEndlessLoop(); (break manually)
  • testEndlessRecursion();
  • testUncaughtException();
Test a breakpoint in a QThread:
  1. Uncomment the call to qthread::testQThread()
  2. Place a breakpoint in qthread::Thread::run()
  3. Run this in the debugger
  4. Make sure that:
    • the breakpoint receives the right number of hits
    • "Locals and Expressions" and "Stack" views show reasonable data
    • "Stack" and "Threads" views show the right names of the threads
Switch on temporarily 'Operate by Instruction' and check whether you see disassembler output and can step by instruction
Check I/O (qDebug, std::cout, std::cerr)
Check "Run in Terminal". Use Terminal for input. (Debbuging might not work on Ubuntu)
Check nothing bad happens on a simple int main() {} program with no breakpoints set automated on Mac
Attach to a core file (Linux/Mac: ulimit –c unlimited)
Attach to a running process (might not work on Ubuntu)
Test unusual situations: Kill X 'externally' while debugging (both in a 'running' and 'stopped' state), where X is
  • the debugged program
  • lldb