Re: Project out of sources compilation

[Konstantin Kharlamov <Hi-Angel@yandex.ru>]

On Sat, 2024-03-16 at 14:12 +0100, Ergus wrote:
> 2. Eglot compilations database place.
> 
> When compilation is out of sources the cmake generated
> compile_commands.json also goes in that directory by default.
> 
> This issue can be managed with a line in dir-locals, or just manually
> coping the database.
> 
> ((eglot-workspace-configuration
> 	  . (:clangd (:initializationOptions
> (:compilationDatabasePath
> 	  "build")))))

Just wanted to clarify two things:

1. You can't just copy clangd database (i.e. `compile_commands.json`)
because the field "directory" has absolute path and clangd doesn't
support relative one. So you'll also have to regexp-replace the paths
after it's been copied.
2. If your out-of-source dir is called `build/`, then you don't need to
configure clangd to support it, because it handles that special case.

> Probably some simple slight integration of Eglot with Project may
> help.
> 
>    2.1 This mixes with the previous one because if we change the
>    compilation directory the line with initializationOptions is not
>    updated and requires manual intervention

Some generic support for pointing out the compilation dir sounds indeed
useful if it's possible.