---
title: C++
description: "Configure C++ language support in Zed, including language servers, formatting, and debugging."
---

# C++

C++ support is available natively in Zed.

- Tree-sitter: [tree-sitter/tree-sitter-cpp](https://github.com/tree-sitter/tree-sitter-cpp)
- Language Server: [clangd/clangd](https://github.com/clangd/clangd)

## Binary

You can configure which `clangd` binary Zed should use.

By default, Zed will try to find a `clangd` in your `$PATH` and try to use that. If that binary successfully executes, it's used. Otherwise, Zed will fall back to installing its own `clangd` version and use that.

If you want to install a pre-release `clangd` version instead you can instruct Zed to do so by setting `pre_release` to `true` in your `settings.json`:

```json [settings]
{
  "lsp": {
    "clangd": {
      "fetch": {
        "pre_release": true
      }
    }
  }
}
```

If you want to disable Zed looking for a `clangd` binary, you can set `ignore_system_version` to `true` in your `settings.json`:

```json [settings]
{
  "lsp": {
    "clangd": {
      "binary": {
        "ignore_system_version": true
      }
    }
  }
}
```

If you want to use a binary in a custom location, you can specify a `path` and optional `arguments`:

```json [settings]
{
  "lsp": {
    "clangd": {
      "binary": {
        "path": "/path/to/clangd",
        "arguments": []
      }
    }
  }
}
```

This `"path"` has to be an absolute path.

## Arguments

You can pass any number of arguments to clangd. To see a full set of available options, run `clangd --help` from the command line. For example with `--function-arg-placeholders=0` completions contain only parentheses for function calls, while the default (`--function-arg-placeholders=1`) completions also contain placeholders for method parameters.

```json [settings]
{
  "lsp": {
    "clangd": {
      "binary": {
        "path": "/path/to/clangd",
        "arguments": ["--function-arg-placeholders=0"]
      }
    }
  }
}
```

## Formatting

By default Zed will use the `clangd` language server for formatting C++ code. Its formatter is the same as the `clang-format` CLI tool. To configure this you can add a `.clang-format` file. For example:

```yaml
# yaml-language-server: $schema=https://json.schemastore.org/clang-format-21.x.json
---
BasedOnStyle: LLVM
IndentWidth: 4
---
Language: Cpp
# Force pointers to the type for C++.
DerivePointerAlignment: false
PointerAlignment: Left
---
```

See [Clang-Format Style Options](https://clang.llvm.org/docs/ClangFormatStyleOptions.html) for a complete list of options.

You can trigger formatting via {#kb editor::Format} or the {#action editor::Format} action from the command palette or by enabling format on save.

Configure formatting in Settings ({#kb zed::OpenSettings}) under Languages > C++, or add to your settings file:

```json [settings]
  "languages": {
    "C++": {
      "format_on_save": "on",
      "tab_size": 2
    }
  }
```

## More server configuration

In the root of your project, it is generally common to create a `.clangd` file to set extra configuration.

```yaml
# yaml-language-server: $schema=https://json.schemastore.org/clangd.json
CompileFlags:
  Add:
    - "--include-directory=/path/to/include"
Diagnostics:
  MissingIncludes: Strict
  UnusedIncludes: Strict
```

For more advanced usage of clangd configuration file, take a look into their [official page](https://clangd.llvm.org/config.html).

## Compile Commands

For some projects Clangd requires a `compile_commands.json` file to properly analyze your project. This file contains the compilation database that tells clangd how your project should be built.

### CMake Compile Commands

With CMake, you can generate `compile_commands.json` automatically by adding the following line to your `CMakeLists.txt`:

```cmake
set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
```

After building your project, CMake will generate the `compile_commands.json` file in the build directory and clangd will automatically pick it up.

## Debugging

You can use CodeLLDB or GDB to debug native binaries. (Make sure that your build process passes `-g` to the C++ compiler, so that debug information is included in the resulting binary.) See below for examples of debug configurations that you can add to `.zed/debug.json`.

- [CodeLLDB configuration documentation](https://github.com/vadimcn/codelldb/blob/master/MANUAL.md#starting-a-new-debug-session)
- [GDB configuration documentation](https://sourceware.org/gdb/current/onlinedocs/gdb.html/Debugger-Adapter-Protocol.html)
  - GDB needs to be at least v14.1

### Build and Debug Binary

```json [debug]
[
  {
    "label": "Debug native binary",
    "build": {
      "command": "make",
      "args": ["-j8"],
      "cwd": "$ZED_WORKTREE_ROOT"
    },
    "program": "$ZED_WORKTREE_ROOT/build/prog",
    "request": "launch",
    "adapter": "CodeLLDB"
  }
]
```

## Protocol Extensions

Zed currently implements the following `clangd` [extensions](https://clangd.llvm.org/extensions):

### Inactive Regions

Automatically dims inactive sections of code due to preprocessor directives, such as `#if`, `#ifdef`, or `#ifndef` blocks that evaluate to false.

### Switch Between Source and Header Files

Allows switching between corresponding C++ source files (e.g., `.cpp`) and header files (e.g., `.h`)
by running the command {#action editor::SwitchSourceHeader} from the command palette or by setting
a keybinding for the `editor::SwitchSourceHeader` action.

```json [keymap]
{
  "context": "Editor",
  "bindings": {
    "alt-enter": "editor::SwitchSourceHeader"
  }
}
```
