As an addendum, I tried downloading the latest provided Emacs Windows build from https://gnu.mirror.constant.com/emacs/windows/ , which reads as:

```

In GNU Emacs 30.1 (build 2, x86_64-w64-mingw32) of 2025-02-23 built on

 AVALON

Windowing system distributor 'Microsoft Corp.', version 10.0.19045

System Description: Microsoft Windows 10 Enterprise (v10.0.2009.19045.5737)

Configured using:

 'configure --with-modules --without-dbus

 --with-native-compilation=aot --without-compress-install

 --with-tree-sitter CFLAGS=-O2 prefix=/g/rel/install/emacs-30.1'

```

And with no other configuration changes and with the same clangd, things work fine (opened the same test2.cpp and attempted to navigate to definition.) So this is most likely a regression, but I haven't been able to pin it down to a specific commit yet.