GDB DAP

A VS Code extension that debugs C/C++ programs using GDB's built-in Debug Adapter Protocol support (gdb -i dap). Since GDB speaks DAP natively, this extension is a thin layer: it just finds a suitable gdb binary and launches it as VS Code's debug adapter.

Requires GDB 16.1 or later, on Linux. Older GDBs run the inferior as part of the DAP launch request instead of deferring it to configurationDone, so breakpoints set before the program starts are never hit, and they ignore stopOnEntry.

Usage

Create a launch configuration in .vscode/launch.json:

{
  "type": "kdap",
  "request": "launch",
  "name": "Launch",
  "program": "${workspaceFolder}/<your program>",
  "args": [],
  "cwd": "${workspaceFolder}",
  "stopOnEntry": true
}

Or use the "GDB DAP: Launch" / "GDB DAP: Attach" / "GDB DAP: Load Core Dump" snippets offered when adding a new configuration.

Launch configuration

• gdbPath: Path to the gdb executable to use, with a leading ~ expanded. Overrides the kdap.gdbPath setting.
• program: Path to the executable to debug. Corresponds to gdb's file command.
• args: Command-line arguments passed to the inferior, as if by set args.
• cwd: The working directory for gdb and the launched program. If omitted, gdb inherits VS Code's working directory rather than the workspace folder, so set this explicitly.
• env: Environment variables for the inferior. Setting this replaces the inferior's entire environment rather than adding to it, so PATH, HOME, etc. must be listed too. If omitted, the inferior inherits gdb's environment.
• stopAtBeginningOfMainSubprogram: Set a temporary breakpoint at main, as if by the start command. Defaults to false.
• stopOnEntry: Set a temporary breakpoint at the program's first instruction, as if by the starti command. Defaults to false.

Attach configuration

• gdbPath: Path to the gdb executable to use, with a leading ~ expanded. Overrides the kdap.gdbPath setting.
• pid: The process ID to which gdb should attach.
• program: Path to the executable being debugged.
• target: The target to which gdb should connect, passed to target remote.
• coreFile: Path to a core dump file to load instead of attaching to a live process.

Settings

• kdap.gdbPath: Path to the gdb binary. Defaults to searching PATH.
• kdap.logPath: Enable DAP logging to this file.
• kdap.logLevel: DAP logging verbosity (default 1).
• kdap.environment: Extra environment variables set on the gdb process itself.
• kdap.qtPrettyPrinters: Automatically load Qt pretty-printers for gdb (default true). If they haven't been downloaded yet, starting a debug session offers to download them; declining starts the session without them.

Commands

• GDB DAP: Download Qt Pretty Printers — downloads the KDevelop Qt gdb pretty-printer scripts into the extension's global storage. Run this once via the Command Palette to enable Qt pretty-printing (see kdap.qtPrettyPrinters above).
• GDB DAP: Debug with Args — starts one of your kdap launch configurations, prompting for the arguments to pass to the inferior instead of using the configuration's args. The input is split like a shell splits a command line, so quote arguments containing spaces.
• GDB DAP: Run with Args — the same, but without debugging: breakpoints and entry stops are ignored.