C: Extend Semantic support

.emacs.d/lisp/init-cc.el

@@ -141,17 +141,24 @@ You can add your mode hook (e.g. `c-mode-hook')."
         (c++-mode . semantic-default-c-setup)))
 ;;; Make sure Semanticdb folders is set before starting semantic.
 (semantic-mode 1)
+;; (global-semantic-stickyfunc-mode)
+;; (global-semantic-decoration-mode)
+;; Eldoc does not work but there is Semantic.
+(global-semantic-idle-summary-mode)
 
-;;; Extra semantic support
-;;; Example:
-;; (when (fboundp 'semantic-add-system-include)
-;;   (semantic-add-system-include "new/header/dir" 'c++-mode)
-;;   (add-to-list 'auto-mode-alist (cons qt4-base-dir 'c++-mode))
-;;   (add-hook
-;;    'c++-mode-hook
-;;    (lambda ()
-;;      (when semantic-mode
-;;        (add-to-list 'semantic-lex-c-preprocessor-symbol-file "new/header/dir/config.h")))))
+;; Add support for some subdir-includes.
+;; TODO: This could be automated by parsing `pkg-config --list-all` or maybe
+;; `find -L .  -maxdepth 1 -type d`.
+(setq semantic-c-dependency-system-include-path
+      (append (mapcar (lambda (lib)
+                        (expand-file-name
+                         lib
+                         (or (getenv "CPATH")
+                             (if (file-directory-p (expand-file-name "~/.guix-profile/include"))
+                                 "~/.guix-profile/include"
+                               "/usr/include"))))
+                      '("glib-2.0" "gtk-3.0" "webkitgtk-4.0"))
+              '("/usr/include")))
 
 (c-add-style
  "ambrevar"