(setq etags-regen-program "C:/green/emacs/emacs-29.3/bin/etags.exe")

(require 'etags-regen)

```

2. Open test.c with the following code

```

#define APPLICATION_WINDOW_WIDTH 320

```

3. M-x etags-regen-mode

4. Move the cursor to APPLICATION_WINDOW_WIDTH and M-x xref-find-definitions. Then the TAGS file is created and the APPLICATION_WINDOW_WIDTH line is highlighted (good).

5. M-x kill-buffer TAGS

6. Add `#define APPLICATION_WINDOW_HEIGHT 320` to test.c and M-x save-buffer

7. Move the cursor to APPLICATION_WINDOW_HEIGHT and M-x xref-find-definitions.

The expected behavior: The TAGS file is updated and the APPLICATION_WINDOW_HEIGHT line is highlighted.

The actual behavior: The echo area reports: "No definition found for: APPLICATION_WINDOW_HEIGHT"

Note that if I don't do step-5 then everything is OK.

Emacs 29.3 has no this feature, I make it available via copy & paste etags-regen.el to load-path. I think this issue has nothing to do with the Emacs version though.

Thanks.

Best regards,

Siyuan Chen