setup lldb debugging with cpp extension in vscode linux

Question

I mostly use gdb for debugging c++ single files in vscode but now want to try lldb but i am facing issues while setting it up for vscode.

I first create default launch.json form debug tab selecting cpp gdb/lldb then clang++ for configuration.

When the debugging starts.. it shows following error:

then in launch.json I changed miDebuggerPath path form /usr/bin/lldb-mi to /usr/bin/lldb.

Then when I launch the debugger it does NOTHING just debug controls up top and following lines in terminal:

warning: ignoring unknown option: --interpreter=mi
warning: ignoring unknown option: --tty=/dev/pts/1

anything I am missing here?

My whole launch.json is:

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "name": "clang++ - Build and debug active file",
            "type": "cppdbg",
            "request": "launch",
            "program": "${fileDirname}/${fileBasenameNoExtension}",
            "args": [],
            "stopAtEntry": false,
            "cwd": "${workspaceFolder}",
            "environment": [],
            "externalConsole": false,
            "MIMode": "lldb",
            "setupCommands": [
                {
                    "description": "Enable pretty-printing for gdb",
                    "text": "-enable-pretty-printing",
                    "ignoreFailures": true
                }
            ],
            "preLaunchTask": "C/C++: clang++ build active file",
            "miDebuggerPath": "/usr/bin/lldb"
        }
    ]
}

Answer 1

lldb-mi is not part of the LLDB project. see lists.llvm.org

you can still build it yourself from the project's github repo. you will need to build LLDB/Clang/LLVM first, since lldb-micompilation requires headers and compiled libraries for the build to work as per information stated in the README.

Answer 2

As mentioned in this answer, and discussed here, using lldb-mi may not be the best option.

lldb-vscode (https://github.com/llvm/llvm-project/tree/main/lldb/tools/lldb-vscode) works well to enable debugging with lldb in vscode on linux, and is part of the LLDB project. Here are the steps I used (taken from the readme) to set it up on a remote-ssh vscode server (assumes llvm installation exists):

1. Create the vscode extension

   # Create directory for a new VSCode extension
   $ mkdir -p  ~/.vscode-server/extensions/llvm-org.lldb-vscode-0.1.0/bin
   # Copy the extension package.json from GitHub
   $ wget -P ~/.vscode-server/extensions/llvm-org.lldb-vscode-0.1.0/ 
   https://raw.githubusercontent.com/llvm/llvm-project/main/lldb/tools/lldb-vscode/package.json
   # Copy the lldb-vscode binary to the bin directory
   $ cp $(which lldb-vscode) ~/.vscode-server/extensions/llvm-org.lldb-vscode-0.1.0/bin/
   # Copy the lldb-server binary to the bin directory
   $ cp $(which lldb-server) ~/.vscode-server/extensions/llvm-org.lldb-vscode-0.1.0/bin/
   # also make sure all libraries are found by ldd for the copied binaries,
   # e.g. liblldb.so.13
   

   Now under the extensions tab in vscode on my remote host, "LLDB native Debug stub" is shown
2. Create a launch.json, for example

   {
       "version": "0.2.0",
       "configurations": [
           {
               "name": "Launch lldb-vscode",
               "type": "lldb-vscode",
               "request": "launch",
               "program": "${command:cmake.launchTargetPath}",
               "args": [],
               "env": [],
               "cwd": "${workspaceFolder}",
               "stopOnEntry": false,
               "sourceMap": [["/path/a/", "/path/b"]]
           }
       ]
   }
   

---

Notes for Ubuntu:

In a Ubuntu distro, llvm can be installed from the package manager, e.g. apt install lldb-13. In this case, lldb-server and lldb-vscode are not on the path so the commands above will not work. Taking a look at the installed package:

$ dpkg --search lldb-vscode
lldb-13: /usr/bin/lldb-vscode-13
lldb-13: /usr/lib/llvm-13/bin/lldb-vscode
$ ls -l /usr/bin/lldb-vscode-13
/usr/bin/lldb-vscode-13 -> ../lib/llvm-13/bin/lldb-vscode

$ dpkg --search lldb-server
lldb-13: /usr/lib/llvm-13/bin/lldb-server
lldb-13: /usr/lib/llvm-13/bin/lldb-server-13
lldb-13: /usr/bin/lldb-server-13
lldb-13: /usr/lib/llvm-13/bin/lldb-server-13.0.0
$ ls -l /usr/bin/lldb-server-13
/usr/bin/lldb-server-13 -> ../lib/llvm-13/bin/lldb-server
$ ls -l /usr/lib/llvm-13/bin/lldb-server*
/usr/lib/llvm-13/bin/lldb-server
/usr/lib/llvm-13/bin/lldb-server-13 -> lldb-server
/usr/lib/llvm-13/bin/lldb-server-13.0.0 -> lldb-server

Therefore, for Ubuntu, for example, cd ~/.vscode-server/extensions/llvm-org.lldb-vscode-0.1.0/bin and do:

$ cp /usr/lib/llvm-13/bin/lldb-vscode .
$ cp /usr/lib/llvm-13/bin/lldb-server .
# make the same symlinks as in the package
$ ln -s lldb-server lldb-server-13
$ ln -s lldb-server lldb-server-13.0.0

Answer 3

CodeLLDB extension works perfectly in Ubuntu docker container launched in Windows 10. It suggests some predefined configs.
I had troubles with gdb that threw out core-dump on multithreaded application; lldb-vscode also required some efforts as discussed in comments of Joe's answer.
PS: Container has gcc clang lldb installed by apt, maybe they are necessary for the plugin to work (maybe not)