How to set clangd for c17

[stokhos]

Hi,

How can I set clangd standards for helix, I tried args = [--std=gnu17] but this doesn't work.

[the-mikedavis]

This should be similar to setting it up for coc-clangd: clangd/coc-clangd#20. It looks like you can specify the standard in the build instructions in compile_flags.txt / compile_commands.json or you should be able to set it globally through the LSP configuration:

# ~/.config/helix/languages.toml
[[language]]
name = "cpp"
config = { "clangd.fallbackFlags" = [ "-std=c++17" ] }
# ^ I haven't tried this. It might instead be
# config = { clangd.fallbackFlags = [ "-std=c++17" ] }
# or
# config = { fallbackFlags = [ "-std=c++17" ] }

[DrunkenRandomWalker]

config = { "clangd.fallbackFlags" = [ "-std=c++17" ] } this works

[Zapeth]

Should this still be working? It seems the entire config value setting is being ignored for me for c and cpp, I can write anything in it and there are no errors reported in log-open (it seems its not even being passed to clangd?)

Setting flags in a compile_flags.txt file works, but I'd prefer having a centralized config.

[norquisd]

@Zapeth this didn't work for me either, so my solution was just to create a static compile_flags.txt location and reference that from languages.toml:

[[language]]
name = "cpp"
language-server = { command = "clangd", args=["--compile-commands-dir=C:\\compile_commands_directory"]}

of course feel free to put compile_commands_directory wherever you want and populate it with compile_flags.txt

[jpsecher]

This works for me with hx 23.10 when I need to pass an argument to clangd:

# .helix/languages.toml
[[language]]
name = "c"

[language-server.clangd.config]
fallbackFlags = ["-DUNIT_TESTING"]

[blakat360]

Imo the following is nicer:

[language-server.clangd]
command = "clangd"
args = ["--enable-config"]

[[language]]
name = "cpp"
language-servers = ["clangd"]
roots = [".git", "CMakeLists.txt"]

This lets you use the following for global options:

  xdg.configFile."clangd/config.yaml".text = ''
    CompileFlags:
      Add: [-std=c++20]
  '';

And you can put a similar file at the root of your project for projecct specific overrides