Changes to header not registering in cpp file

[lane-s]

If I have a header file and a cpp file open at the same time and add a function prototype to the header, I would expect to be able to write the function implementation in the cpp buffer without any errors.

However, usually I get the message that the function I'm implementing is not defined. Sometimes saving both files seems to trigger everything to refresh, but otherwise the only way I know how to fix it is by restarting the lsp workspace.

Any idea what's causing this? I'm not sure if it's a problem with emacs-ccls or lsp-mode in general, but I figured I'd ask here first. Thanks

[MaskRay]

// a.cc
#include "a.h"
int main() { foo(); }
// a.h
// empty

There is "use of undeclared identifier 'foo'" error message published by textDocument/publishDiagnostics. Then, if you put void foo(); into a.h and make an edit in a.cc, the edit causes the client (lsp-mode) to send a textDocument/didChange notification to the ccls server. ccls will thereby send an empty textDocument/publishDiagnostics to indicate the error has been fixed.

Sometimes there may be lingering diagnostics, but that is probably lsp-ui-flycheck (or flycheck) or flymake's problem.

[lane-s]

Thank you. Now that I know what to look for in the logs, it seems the empty publishDiagnostics message is being sent, so the problem is with lsp-ui.

[MaskRay]

If you use lsp-ui-flycheck, see emacs-lsp/lsp-ui#214