Qt Creator ManualTests DebuggerCdb

From Qt Wiki
Revision as of 10:47, 30 June 2023 by Robert Loehning (talk | contribs) (Clarify what the comments in simple.pro are for)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search


For the following tests, you will need to build projects on Qt using MSVC and debug them using cdb. You can get a suitable build of Qt from the official Online Installer.

Tests using tests/manual/debugger/simple/simple.pro from Qt Creator's source repository
Test Result Annotation
Create new project. Can you build, run and debug it? automated
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.
Test breakpoint module resolution (see below)
"Step into" a couple of times. Can you step into Qt source code (*.cpp file under QTDIR. You might need to configure source paths mapping under "Edit" -> "Preferences…" -> "Debugger" -> "General" -> "Add Qt sources...")?
Test debugging helpers: Do classes like QImage or std::string show beautiful information instead of the raw structure? automated
Step through some (not all) test* functions and check whether the displayed data looks correct The code contains comments with the expected displayed data. These are meant for semi-automatic runs and might differ from what you see. Use your own judgement what's correct and what's not.
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, including the object names of the threads
Switch on temporarily 'Operate by Instruction' (small icon above the stack trace) and check whether you see disassembler output and can step by instruction
Tests using tests/manual/debugger/cli-io/cli-io.pro from Qt Creator's source repository
Test Result Annotation
Check I/O (qDebug, std::cout, std::cerr), on Win for both Debug and Release. Please read the below note!
Check "Run in Terminal". Use Terminal for input.
Check nothing bad happens on a simple int main() {} program with no breakpoints set automated
Tests using tests/manual/debugger/gui/gui.pro from Qt Creator's source repository
Test Result Annotation
Check registering for post-mortem debugging:
  1. Go to "Edit" -> "Preferences…" -> "Debugger" -> "General".
  2. Toggle "Use Qt Creator for post-mortem debugging"
  3. Click "OK"
  4. Go to "Edit" -> "Preferences…" -> "Debugger"-> "General" again.
  5. Verify that the check box "Use Qt Creator for post-mortem debugging" reflects the changes you made in step 2.
Attach to a crashed process
  1. Start the project from outside Creator, e.g. from the command line.
  2. Attach Creator to the running process.
    Verify that you see a stack trace, variable values and code markers just as if you had run the application in the debugger from the beginning. You should also be able to pause/continue the execution.
Test unusual situations: Kill X 'externally' while debugging (both in a 'running' and 'stopped' state), where X is
  • the debugged program
  • cdb

Breakpoint module resolution

  • Set a new breakpoint in application code (say 'testapp').
  • Right-click into the breakpoint view and make sure that "Use Tooltips (...)" is checked.
  • Hover over breakpoint view, verify that 'Module' is empty in tooltip.
  • Start the application, make it stop at breakpoint.
  • Finish debugging, restart debugger. Should be faster now.
  • Display tooltip of breakpoint again. Module should now be something 'testapp'.

stderr/stdout handling on Windows

  • An application needs to be built with 'console' for stderr/stdout to appear (use Creator's "Run in terminal" setting)
  • Creator itself is built with 'console' in debug mode only.
  • qDebug() prints to stderr for 'console' apps, else to the Windows debugger log, which can be shown with the DbgView utility
  • CDB will catch only qDebug() when app is built without ‘console’, rest goes to app console as with normal Windows app