[lldb-dap] VSCode extension ignores console parameter and defaults to debug console

[eddienubes]

Prerequisites

Hi wonderful people!
I didn't have much success setting up the lldb-dap extension.
The console parameter seems to be completely ignored, I expect the extension to spawn an integrated terminal instance running the executable. However, it doesn't.
Setting the console value to externalTerminal also doesn't seem to affect anything. The extension simple pipes stdout to Debug Console without any means to interact with the program.
I also attached a quick recording demonstrating the difference between lldb-dap and CodeLLDB.

Steps to reproduce

1. Install the extension from marketplace - https://github.com/eddienubes/c-adventures/tree/lldb-dap-bug-repro
2. Run Select and Start Debugging from command palette
3. Compare the behaviour of lldb-dap extension (named MacOS LLDB) vs CodeLLDB (named MacOS CodeLLDB).
4. The former doesn't spawn an integrated terminal session, meaning it ignores the console parameter.

Environment

M1 Pro MacOS 15.6.1
VSCode 1.104.3
lldb-dap 21.1.2

CleanShot.2025-10-05.at.8.17.08.mp4

[llvmbot]

@llvm/issue-subscribers-lldb-dap

Author: Dmytro Tiapukhin (eddienubes)

## Prerequisites Hi wonderful people! I didn't have much success setting up the `lldb-dap` extension. The `console` parameter seems to be completely ignored, I expect the extension to spawn an integrated terminal instance running the executable. However, it doesn't. Setting the `console` value to _externalTerminal_ also doesn't seem to affect anything. The extension simple pipes stdout to `Debug Console` without any means to interact with the program. I also attached a quick recording demonstrating the difference between `lldb-dap` and `CodeLLDB`.

Steps to reproduce

1. Install the extension from marketplace - https://github.com/eddienubes/c-adventures/tree/lldb-dap-bug-repro
2. Run Select and Start Debugging from command palette
3. Compare the behaviour of lldb-dap extension (named MacOS LLDB) vs CodeLLDB (named MacOS CodeLLDB).
4. The former doesn't spawn an integrated terminal session, meaning it ignores the console parameter.

Environment

M1 Pro MacOS 15.6.1
VSCode 1.104.3
lldb-dap 21.1.2

CleanShot.2025-10-05.at.8.17.08.mp4

[ashgti]

The bottom panel Debug Console does correspond to the integratedTerminal setting. If you want the output in the terminal window you would need to set it to externalTerminal.

[ashgti]

Ah, wait I'm mixing up internalConsole and integratedTerminal, my mistake. Looking to see if I can reproduce this.

[ashgti]

Trying this locally, it is launching in the integrated terminal for me, but the debugger is always timing out. I suspect that has something to do with our FIFO file read/writer.

[ashgti]

Ah, the timeout on my side was due to using lldb-dap with full debug symbols. It just took a little while for the debug symbols to load.

[ashgti]

Does using "runInTerminal": true work?

[da-viper]

@eddienubes could you run lldb-dap version as the console option was recently added.

[eddienubes]

Does using "runInTerminal": true work?

Nope,
Failed to attach to the target process. Timed out trying to get messages from the runInTerminal launcher
After setting the correct executable path, it does.

@eddienubes could you run lldb-dap version as the console option was recently added.

I think I figured out the culprit. The extension uses the built-in lldb that comes with xcode tools by default. Even if I have a newer llvm (+ lldb/lldb-dap) installed via homebrew and available in the PATH.
So, yes, if I run lldb-dap --version, it'll yield

lldb-dap: Homebrew LLVM version 21.1.2
  Optimized build.
liblldb: lldb version 21.1.2

as in the issue description, but that's not what extension's going to use as per its output:

2025-10-08 11:49:07.235 [info] lldb-dap path: /Library/Developer/CommandLineTools/usr/bin/lldb-dap

I resolved it with an explicit setting
"lldb-dap.executable-path": "/opt/homebrew/opt/llvm/bin/lldb-dap",
However, it'd be nice to infer the lldb-dap available in the PATH.
Yes, I have export PATH="/opt/homebrew/opt/llvm/bin:$PATH" in my .zshrc

What's interesting is that the description says.

By default, the VS Code extension will expect to find lldb-dap in your PATH

but it doesn't, or does it?

Going further on internalTerminal output between lldb-dap and codelldb, I see that codelldb:

1. Spawns/Reuses the terminal instance
2. Clears it
3. Executes the program
4. Clears the command used to execute the program to avoid long absolute paths polluting the terminal.
5. What's left is pure stdout of the executable.

@ashgti @da-viper

[da-viper]

llvm-project/lldb/tools/lldb-dap/src-ts/debug-adapter-factory.ts

Lines 52 to 68 in 6359980

	async function findDAPExecutable(): Promise<string | undefined> {
	const executable = process.platform === "win32" ? "lldb-dap.exe" : "lldb-dap";
	// Prefer lldb-dap from Xcode on Darwin.
	const xcrun_dap = await findWithXcrun(executable);
	if (xcrun_dap) {
	return xcrun_dap;
	}
	// Find lldb-dap in the user's path.
	const path_dap = await findInPath(executable);
	if (path_dap) {
	return path_dap;
	}
	return undefined;

It is correct, It currently prioritises lldb-dap from Xcode.

But not sure if it is meant to request lldb-dap from Xcode after it is not found in the path

maybe @JDevlieghere can confirm if the current behaviour is intended