qt-debugging

Qt Debugging

Diagnostic Approach

1. Read the full Qt warning output — Qt prints actionable warnings before crashes
2. Categorize the failure type (see categories below)
3. Isolate — reproduce with a minimal test case
4. Fix and verify with QT_QPA_PLATFORM=offscreen pytest

Enabling Verbose Qt Output

# Show all Qt debug/warning messages
QT_LOGGING_RULES="*.debug=true" python -m myapp

# Filter to specific categories
QT_LOGGING_RULES="qt.qpa.*=true;qt.widgets.*=true" python -m myapp

# C++