Incoming calls not working

Using clangd with the following MWE:

main.c

#include <stdio.h>

void foo() {
    printf("Hello world\n");
}

int main() {
    foo();
}

compile_commands.json

[
    {
        "directory": "<ABSOLUTE PATH TO DIRECTORY CONTAINING main.c>",
        "arguments": ["clang", "main.c"],
        "file": "main.c"
    }
]

If I place the cursor over the symbol foo on line 3 and execute the command :IncomingCalls then I see an error message Incoming calls not found, whereas if I run :lua vim.lsp.buf.incoming_calls() then a quickfix window appears with a single entry main.c|8 col 5| main, corresponding with the position at which foo is called from main.

gfanto / fzf-lsp.nvim

Incoming calls not working #39