1# C++
2
3C++ support is available natively in Zed.
4
5- Tree-sitter: [tree-sitter/tree-sitter-cpp](https://github.com/tree-sitter/tree-sitter-cpp)
6- Language Server: [clangd/clangd](https://github.com/clangd/clangd)
7
8## Binary
9
10You can configure which `clangd` binary Zed should use.
11
12By 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.
13
14If 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`:
15
16```json [settings]
17{
18 "lsp": {
19 "clangd": {
20 "fetch": {
21 "pre_release": true
22 }
23 }
24 }
25}
26```
27
28If you want to disable Zed looking for a `clangd` binary, you can set `ignore_system_version` to `true` in your `settings.json`:
29
30```json [settings]
31{
32 "lsp": {
33 "clangd": {
34 "binary": {
35 "ignore_system_version": true
36 }
37 }
38 }
39}
40```
41
42If you want to use a binary in a custom location, you can specify a `path` and optional `arguments`:
43
44```json [settings]
45{
46 "lsp": {
47 "clangd": {
48 "binary": {
49 "path": "/path/to/clangd",
50 "arguments": []
51 }
52 }
53 }
54}
55```
56
57This `"path"` has to be an absolute path.
58
59## Arguments
60
61You 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.
62
63```json [settings]
64{
65 "lsp": {
66 "clangd": {
67 "binary": {
68 "path": "/path/to/clangd",
69 "arguments": ["--function-arg-placeholders=0"]
70 }
71 }
72 }
73}
74```
75
76## Formatting
77
78By default Zed will use the `clangd` language server for formatting C++ code. The Clangd is the same as the `clang-format` CLI tool. To configure this you can add a `.clang-format` file. For example:
79
80```yaml
81# yaml-language-server: $schema=https://json.schemastore.org/clang-format-21.x.json
82---
83BasedOnStyle: LLVM
84IndentWidth: 4
85---
86Language: Cpp
87# Force pointers to the type for C++.
88DerivePointerAlignment: false
89PointerAlignment: Left
90---
91```
92
93See [Clang-Format Style Options](https://clang.llvm.org/docs/ClangFormatStyleOptions.html) for a complete list of options.
94
95You can trigger formatting via {#kb editor::Format} or the `editor: format` action from the command palette or by adding `format_on_save` to your Zed settings:
96
97```json [settings]
98 "languages": {
99 "C++": {
100 "format_on_save": "on",
101 "tab_size": 2
102 }
103 }
104```
105
106## More server configuration
107
108In the root of your project, it is generally common to create a `.clangd` file to set extra configuration.
109
110```yaml
111# yaml-language-server: $schema=https://json.schemastore.org/clangd.json
112CompileFlags:
113 Add:
114 - "--include-directory=/path/to/include"
115Diagnostics:
116 MissingIncludes: Strict
117 UnusedIncludes: Strict
118```
119
120For more advanced usage of clangd configuration file, take a look into their [official page](https://clangd.llvm.org/config.html).
121
122## Compile Commands
123
124For some projects Clangd requires a `compile_commands.json` file to properly analyze your project. This file contains the compilation database that tells clangd how your project should be built.
125
126### CMake Compile Commands
127
128With CMake, you can generate `compile_commands.json` automatically by adding the following line to your `CMakeLists.txt`:
129
130```cmake
131set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
132```
133
134After building your project, CMake will generate the `compile_commands.json` file in the build directory and clangd will automatically pick it up.
135
136## Debugging
137
138You can use CodeLLDB or GDB to debug native binaries. (Make sure that your build process passes `-g` to the C++ compiler, so that debug information is included in the resulting binary.) See below for examples of debug configurations that you can add to `.zed/debug.json`.
139
140- [CodeLLDB configuration documentation](https://github.com/vadimcn/codelldb/blob/master/MANUAL.md#starting-a-new-debug-session)
141- [GDB configuration documentation](https://sourceware.org/gdb/current/onlinedocs/gdb.html/Debugger-Adapter-Protocol.html)
142 - GDB needs to be at least v14.1
143
144### Build and Debug Binary
145
146```json [debug]
147[
148 {
149 "label": "Debug native binary",
150 "build": {
151 "command": "make",
152 "args": ["-j8"],
153 "cwd": "$ZED_WORKTREE_ROOT"
154 },
155 "program": "$ZED_WORKTREE_ROOT/build/prog",
156 "request": "launch",
157 "adapter": "CodeLLDB"
158 }
159]
160```