How to solve coc-clangd error “clang pp_file_not_found”

[Sipym]

When I was writing a project about C language, I found that coc-clangd always reported an error "",and the project directory structure is as follows,

This is the error message:

I don't know how to get clangd to get the header file information of my project. Is there any solution?
Thank you for your reply.

[fannheyward]

You need to setup compile_commands.json for clangd.

[Sipym]

Thank you,i have solved this problem.