Debugging with VSCode

Debugging C++ Code

First, you need to build BARK in the debug mode using

bazel build //... --compilation_mode=dbg

Additionally, you need to modify the .vscode/launch.json in Visual Studio Code and then launch the debugger (F5 in the current file).

  "name": "(gdb) Launch",
  "type": "cppdbg",
  "request": "launch",
  "program": "${workspaceFolder}/bazel-bin/{path-to-executable-file}",
  "args": [],
  "stopAtEntry": true,
  "cwd": "${workspaceFolder}",
  "environment": [],
  "externalConsole": true,
  "MIMode": "gdb",
  "setupCommands": [
      "description": "Enable pretty-printing for gdb",
      "text": "-enable-pretty-printing",
      "ignoreFailures": true

Now, you can set breakpoints and debug the c++ code.

Debugging Python Code

To debug python code, you need to add the following code in the .vscode/launch.json:

  "name": "Python: Current File",
  "type": "python",
  "request": "launch",
  "program": "${file}",
  "console": "integratedTerminal",
  "env": {
    "PYTHONPATH": "${workspaceFolder}/bazel-bin/examples/{path-to-executable-file}.runfiles/__main__/python:${workspaceFolder}/bazel-bin/examples/{path-to-executable-file}.runfiles/__main__"

Make sure to be in the main executable file when launching the debugger (F5).

Debugging C++ and Python

Here, both debuggers need to be run in parallel. First, we need to build the “” in the debug mode by running bazel build //... --compilation_mode=dbg. You can also check if the “” contains debug symbols by running readelf --debug-dump=decodedline Then, add the following launch configuration and adapt the path in the .vscode/launch.json:

  "name": "(gdb) Attach",
  "type": "cppdbg",
  "request": "attach",
  "program": "${workspaceFolder}/python/venv/bin/python3",
  "cwd" : "${workspaceFolder}",
  "processId": "${command:pickProcess}",
  "MIMode": "gdb",
  "sourceFileMap" : {"/proc/self/cwd/": "${workspaceFolder}"},

Debugging process:

  1. Add a breakpoint in the python file you want to debug, somewhere before an interesting code section, run the launch configuration “Python: Current File” (see before) and wait until the breakpoint is reached.
  2. Run the “(gdb) Attach” launch configuration, select the python interpreter whose path contains “/.vscode/”. You will be promted to enter your user password.
  3. Set breakpoints in the C++ Files
  4. The python debugger is currently stopped at a break point. Switch back from the debugger “(gdb) Attach” to the other debugger “Python: Current File” and press F5 (Continue). Now, vscode automatically jumps between the two debuggers between python and c++ code.

Memory Checking

Use Valgrind to profile the code in order to find memory leaks.

  1. Build the target with debug symbols, i.e. bazel test //bark/world/tests:py_map_interface_tests --compilation_mode=dbg
  2. Profile via valgrind --track-origins=yes --keep-stacktraces=alloc-and-free --leak-check=full ./bazel-bin/{path-to-executable-file}.