PyCharm 2018.2 Help

Python Debugger

File | Settings | Build, Execution, Deployment | Python Debugger for Windows and Linux
PyCharm | Preferences | Build, Execution, Deployment | Python Debugger for macOS
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Use this page to configure Python debug options.

ItemDescription
Attach to subprocess automatically while debuggingIf this checkbox is selected, PyCharm will automatically attach all subprocesses of the process being debugged. Thus, if the parent process has subprocesses, their breakpoints will always work.
Collect run-time types information for code insightIf this checkbox is selected, the types of function calls are preserved during debugging, and passed to the type checker. Refer to the section Using Docstrings to Specify Types for details.
Clear cachesClick this button to remove information about the types of arguments, collected at run time.
Gevent compatibleIf this checkbox is selected, the debugger will be compatible with the Gevent-monkeypatched code.
PyQt compatibleIf PyQt is installed on the interpreter, but is not imported in the application code, some import errors may occur. Unchecking this option fixes these errors.

If you have multiple PyQt backends, installed on your interpreter, you have to select the PyQt backend from the drop-down list. By default, the Auto option is enabled, which means that the backend first found will be used.

For Attach to Process show process with names containing:A string pattern specified in this field will be used to show processes in the Attach to Process list. The default pattern is "python".

Note that the debugger contains speedup modules, which use Cython and are generated with a few changes in the regular files to cythonize the files. The Cython speedups are available for CPython versions 2.7, 3.4 and 3.5.

  • On Windows the compiled Cython extensions are bundled with PyCharm.
  • On Linux and Mac OS, Cython extensions should be compiled manually in one in two possible ways:
    • by clicking the link that appears in the warning after the first debugger launch.
    • by running the command from the warning manually in the terminal. A separate Cython extension should be compiled for each version of Python interpreter.

    If someone doesn't want to use Cython extensions for some reasons, the environment variable PYDEVD_USE_CYTHON=NO should be passed.

Last modified: 20 July 2018

See Also

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