The absence of `lldb-mi` prevents debugging `clang`-compiled programs with `gdb`, meaning that even if the `clang` task is set as the default, the configuration still needs to be manually selected each time the program is run.

Environment

• OS and version: Windows 24H2
• VS Code: 1.96.2
• C/C++ extension: 1.22.11
• OS and version of remote machine (if applicable): Ubuntu 24.04 WSL
• GDB / LLDB version: 15.0.50.20240403-git

Bug Summary and Steps to Reproduce

Bug Summary:

Even when configured to use gdb to debug programs compiled with clang, the C/C++ extension still ignores the clang debug configuration due to the absence of lldb-mi. This results in the need to manually select the configuration each time the program is run, even if the clang task is set as the default.

Related issue: #12006, but this is not a duplicate (I'm not using lldb at all).

Steps to reproduce:

1. I have already configured to use gdb instead of lldb to debug programs compiled with clang:

"MIMode": "gdb",
"miDebuggerPath": "/usr/bin/gdb"

2. C/C++ extension still shows:

Unable to find the "lldb-mi-19" debugger. The debug configuration for clang-19 is ignored.
Unable to find the "lldb-mi-19" debugger. The debug configuration for clang++-19 is ignored.

and I have to manually select the configuration each time the program is run, even if the clang task is set as the default:

"group": {
    "kind": "build",
    "isDefault": true
},

Debugger Configurations

task.json:

{
    "tasks": [
        {
            "type": "cppbuild",
            "label": "C/C++: clang++-19 build active file",
            "command": "/usr/bin/clang++-19",
            "args": [
                "-std=c++23",
                "-fstandalone-debug",
                "-fsanitize=undefined",
                "-fsanitize=address",
                "-fcolor-diagnostics",
                "-fansi-escape-codes",
                "-g",
                "${file}",
                "-o",
                "${fileDirname}/${fileBasenameNoExtension}"
            ],
            "options": {
                "cwd": "${fileDirname}"
            },
            "problemMatcher": [
                "$gcc"
            ],
            "group": {
                "kind": "build",
                "isDefault": true
            },
            "detail": "Task generated by Debugger."
        }
    ],
    "version": "2.0.0"
}

launch.json

{
    "configurations": [
        {
            "name": "C/C++: clang++-19 build and debug active file",
            "type": "cppdbg",
            "request": "launch",
            "program": "${fileDirname}/${fileBasenameNoExtension}",
            "args": [],
            "stopAtEntry": false,
            "cwd": "${fileDirname}",
            "environment": [],
            "externalConsole": false,
            "MIMode": "gdb",
            "setupCommands": [
                {
                    "description": "Enable pretty-printing for gdb",
                    "text": "-enable-pretty-printing",
                    "ignoreFailures": true
                },
                {
                    "description": "Set Disassembly Flavor to Intel",
                    "text": "-gdb-set disassembly-flavor intel",
                    "ignoreFailures": true
                }
            ],
            "preLaunchTask": "C/C++: clang++-19 build active file",
            "miDebuggerPath": "/usr/bin/gdb"
        }
    ],
    "version": "2.0.0"
}

C/C++ Extension Logs

Unable to find the "lldb-mi-19" debugger. The debug configuration for clang-19 is ignored.
Unable to find the "lldb-mi-19" debugger. The debug configuration for clang++-19 is ignored.

Reference:

• #5415
• https://askubuntu.com/questions/1508260/how-do-i-install-clang-18-on-ubuntu

Start by reproducing the behavior with the task.json and launch.json configurations shown, then inspect how the extension selects debugger configurations and handles the lldb-mi-19 warning. Done means a clang build configuration using MIMode gdb and miDebuggerPath /usr/bin/gdb is not ignored and does not require manual selection each run.