How to configure lsp-mode + clangd to show all references to a symbol without first opening the referencing files?

[bgoodr]

Hi,

I'm using clangd version 11.0 with lsp-mode version 20220405.1024 installed via the package manager (not from source). I have it configured properly as far as I can tell: I can use M-. to go to a definition in my C++ source code. However, if I use M-? (bound to xref-find-references) it only shows references to the symbol in buffers that are already open. I need lsp-mode to display a list of all references across the entire project, but that is not happening properly.

For testing/debugging purposes, I have shortened my compile_commands.json file to a subset of my source tree down to a handful of files, some of which define the symbols, and others that reference to them via #include'ing a header file that declares those symbols. Opening up the .C file that defines, say, a member function, and running M-? on that symbol currently only shows the symbol in that file that defines it. Then, if I open up a different .C file, that refers to that symbol, and use M-? on that symbol, then and only then does it show that different .C file and the .C file that defines that symbol.

I've also contacted the Discord channel for the clangd backend (see my question), explaining my situation, and they gave me some things to try, which I did, but they did not reveal anything useful (see comment1, comment2, and comment3.

Per one of the suggestions, I've added --log=verbose to the clang arguments via:

(setq lsp-clients-clangd-args '("--header-insertion-decorators=0" "-j=4" "-background-index" "-log=verbose"))

but I'm not seeing any errors or warnings that would lead me to believe that things are not configured properly.

So, Is there anything I can do in my lsp-mode configuration to enable showing all of the references across the entire project?

Thanks!