diff --git a/src/main.c b/src/main.c
index 4c41c0f..1c53da2 100644
--- a/src/main.c
+++ b/src/main.c
@@ -104,7 +104,7 @@ void handle_event_property_notify(XEvent *e)
         // Change name of desktops
         else if (at == server.atom._NET_DESKTOP_NAMES) {
             if (debug)
-                fprintf(stderr, "tint2: %s %d: win = root, atom = _NET_DESKTOP_NAMES\n", __FUNCTION__, __LINE__);
+                fprintf(stderr, "tint2: %s %d: win = root, atom = _NET_DESKTOP_NAMES\n", __func__, __LINE__);
             update_desktop_names();
         }
         // Change desktops
@@ -112,7 +112,7 @@ void handle_event_property_notify(XEvent *e)
                  at == server.atom._NET_DESKTOP_VIEWPORT || at == server.atom._NET_WORKAREA ||
                  at == server.atom._NET_CURRENT_DESKTOP) {
             if (debug)
-                fprintf(stderr, "tint2: %s %d: win = root, atom = ?? desktops changed\n", __FUNCTION__, __LINE__);
+                fprintf(stderr, "tint2: %s %d: win = root, atom = ?? desktops changed\n", __func__, __LINE__);
             if (!taskbar_enabled)
                 return;
             int old_num_desktops = server.num_desktops;
@@ -202,7 +202,7 @@ void handle_event_property_notify(XEvent *e)
         // Window list
         else if (at == server.atom._NET_CLIENT_LIST) {
             if (debug)
-                fprintf(stderr, "tint2: %s %d: win = root, atom = _NET_CLIENT_LIST\n", __FUNCTION__, __LINE__);
+                fprintf(stderr, "tint2: %s %d: win = root, atom = _NET_CLIENT_LIST\n", __func__, __LINE__);
             taskbar_refresh_tasklist();
             update_all_taskbars_visibility();
             schedule_panel_redraw();
@@ -210,12 +210,12 @@ void handle_event_property_notify(XEvent *e)
         // Change active
         else if (at == server.atom._NET_ACTIVE_WINDOW) {
             if (debug)
-                fprintf(stderr, "tint2: %s %d: win = root, atom = _NET_ACTIVE_WINDOW\n", __FUNCTION__, __LINE__);
+                fprintf(stderr, "tint2: %s %d: win = root, atom = _NET_ACTIVE_WINDOW\n", __func__, __LINE__);
             reset_active_task();
             schedule_panel_redraw();
         } else if (at == server.atom._XROOTPMAP_ID || at == server.atom._XROOTMAP_ID) {
             if (debug)
-                fprintf(stderr, "tint2: %s %d: win = root, atom = _XROOTPMAP_ID\n", __FUNCTION__, __LINE__);
+                fprintf(stderr, "tint2: %s %d: win = root, atom = _XROOTPMAP_ID\n", __func__, __LINE__);
             // change Wallpaper
             for (int i = 0; i < num_panels; i++) {
                 set_panel_background(&panels[i]);
@@ -234,7 +234,7 @@ void handle_event_property_notify(XEvent *e)
             char *atom_name = XGetAtomName(server.display, at);
             fprintf(stderr,
                     "%s %d: win = %ld, task = %s, atom = %s\n",
-                    __FUNCTION__,
+                    __func__,
                     __LINE__,
                     win,
                     task ? (task->title ? task->title : "??") : "null",
@@ -243,7 +243,7 @@ void handle_event_property_notify(XEvent *e)
         }
         if (!task) {
             if (debug)
-                fprintf(stderr, "tint2: %s %d\n", __FUNCTION__, __LINE__);
+                fprintf(stderr, "tint2: %s %d\n", __func__, __LINE__);
             if (at == server.atom._NET_WM_STATE) {
                 // xfce4 sends _NET_WM_STATE after minimized to tray, so we need to check if window is mapped
                 // if it is mapped and not set as skip_taskbar, we must add it to our task list
@@ -277,7 +277,7 @@ void handle_event_property_notify(XEvent *e)
                 Atom *atom_state = server_get_property(win, server.atom._NET_WM_STATE, XA_ATOM, &count);
                 for (int j = 0; j < count; j++) {
                     char *atom_state_name = XGetAtomName(server.display, atom_state[j]);
-                    fprintf(stderr, "tint2: %s %d: _NET_WM_STATE = %s\n", __FUNCTION__, __LINE__, atom_state_name);
+                    fprintf(stderr, "tint2: %s %d: _NET_WM_STATE = %s\n", __func__, __LINE__, atom_state_name);
                     XFree(atom_state_name);
                 }
                 XFree(atom_state);
diff --git a/src/panel.h b/src/panel.h
index 2d440e3..9409539 100644
--- a/src/panel.h
+++ b/src/panel.h
@@ -165,7 +165,7 @@ gboolean resize_panel(void *obj);
 void render_panel(Panel *panel);
 void shrink_panel(Panel *panel);
 void _schedule_panel_redraw(const char *file, const char *function, const int line);
-#define schedule_panel_redraw() _schedule_panel_redraw(__FILE__, __FUNCTION__, __LINE__)
+#define schedule_panel_redraw() _schedule_panel_redraw(__FILE__, __func__, __LINE__)
 
 void set_panel_items_order(Panel *p);
 void place_panel_all_desktops(Panel *p);
diff --git a/src/systray/systraybar.c b/src/systray/systraybar.c
index 8d94db5..7fe2c84 100644
--- a/src/systray/systraybar.c
+++ b/src/systray/systraybar.c
@@ -184,7 +184,7 @@ int systray_compute_desired_size(void *obj)
 gboolean resize_systray(void *obj)
 {
     if (systray_profile)
-        fprintf(stderr, "tint2: [%f] %s:%d\n", profiling_get_time(), __FUNCTION__, __LINE__);
+        fprintf(stderr, "tint2: [%f] %s:%d\n", profiling_get_time(), __func__, __LINE__);
 
     int size;
     systray_compute_geometry(&size);
@@ -227,7 +227,7 @@ gboolean resize_systray(void *obj)
 void draw_systray(void *obj, cairo_t *c)
 {
     if (systray_profile)
-        fprintf(stderr, BLUE "tint2: [%f] %s:%d" RESET "\n", profiling_get_time(), __FUNCTION__, __LINE__);
+        fprintf(stderr, BLUE "tint2: [%f] %s:%d" RESET "\n", profiling_get_time(), __func__, __LINE__);
     if (systray_composited) {
         if (render_background)
             XFreePixmap(server.display, render_background);
@@ -271,7 +271,7 @@ void systray_dump_geometry(void *obj, int indent)
 void on_change_systray(void *obj)
 {
     if (systray_profile)
-        fprintf(stderr, "tint2: [%f] %s:%d\n", profiling_get_time(), __FUNCTION__, __LINE__);
+        fprintf(stderr, "tint2: [%f] %s:%d\n", profiling_get_time(), __func__, __LINE__);
     if (systray.icons_per_column == 0 || systray.icons_per_row == 0)
         return;
 
@@ -301,7 +301,7 @@ void on_change_systray(void *obj)
         if (systray_profile)
             fprintf(stderr,
                     "%s:%d win = %lu (%s), parent = %lu, x = %d, y = %d\n",
-                    __FUNCTION__,
+                    __func__,
                     __LINE__,
                     traywin->win,
                     traywin->name,
@@ -358,7 +358,7 @@ void on_change_systray(void *obj)
 void start_net()
 {
     if (systray_profile)
-        fprintf(stderr, "tint2: [%f] %s:%d\n", profiling_get_time(), __FUNCTION__, __LINE__);
+        fprintf(stderr, "tint2: [%f] %s:%d\n", profiling_get_time(), __func__, __LINE__);
     if (net_sel_win) {
         // protocol already started
         if (!systray_enabled)
@@ -464,7 +464,7 @@ void start_net()
 
     fprintf(stderr, GREEN "tint2: systray started" RESET "\n");
     if (systray_profile)
-        fprintf(stderr, "tint2: [%f] %s:%d\n", profiling_get_time(), __FUNCTION__, __LINE__);
+        fprintf(stderr, "tint2: [%f] %s:%d\n", profiling_get_time(), __func__, __LINE__);
     XClientMessageEvent ev;
     ev.type = ClientMessage;
     ev.window = server.root_win;
@@ -481,7 +481,7 @@ void start_net()
 void handle_systray_event(XClientMessageEvent *e)
 {
     if (systray_profile)
-        fprintf(stderr, "tint2: [%f] %s:%d\n", profiling_get_time(), __FUNCTION__, __LINE__);
+        fprintf(stderr, "tint2: [%f] %s:%d\n", profiling_get_time(), __func__, __LINE__);
 
     Window win;
     unsigned long opcode = e->data.l[1];
@@ -509,7 +509,7 @@ void handle_systray_event(XClientMessageEvent *e)
 void stop_net()
 {
     if (systray_profile)
-        fprintf(stderr, "tint2: [%f] %s:%d\n", profiling_get_time(), __FUNCTION__, __LINE__);
+        fprintf(stderr, "tint2: [%f] %s:%d\n", profiling_get_time(), __func__, __LINE__);
     if (systray.list_icons) {
         // remove_icon change systray.list_icons
         while (systray.list_icons)
@@ -529,7 +529,7 @@ gboolean error;
 int window_error_handler(Display *d, XErrorEvent *e)
 {
     if (systray_profile)
-        fprintf(stderr, RED "tint2: [%f] %s:%d" RESET "\n", profiling_get_time(), __FUNCTION__, __LINE__);
+        fprintf(stderr, RED "tint2: [%f] %s:%d" RESET "\n", profiling_get_time(), __func__, __LINE__);
     error = TRUE;
     if (e->error_code != BadWindow) {
         fprintf(stderr, RED "tint2: systray: error code %d" RESET "\n", e->error_code);
@@ -623,7 +623,7 @@ gboolean add_icon(Window win)
 
     char *name = get_window_name(win);
     if (systray_profile)
-        fprintf(stderr, "tint2: [%f] %s:%d win = %lu (%s)\n", profiling_get_time(), __FUNCTION__, __LINE__, win, name);
+        fprintf(stderr, "tint2: [%f] %s:%d win = %lu (%s)\n", profiling_get_time(), __func__, __LINE__, win, name);
     Panel *panel = systray.area.panel;
 
     // Get the process ID of the application that created the window
@@ -748,14 +748,14 @@ gboolean add_icon(Window win)
     }
 
     if (systray_profile)
-        fprintf(stderr, "tint2: [%f] %s:%d\n", profiling_get_time(), __FUNCTION__, __LINE__);
+        fprintf(stderr, "tint2: [%f] %s:%d\n", profiling_get_time(), __func__, __LINE__);
 
     // Resize and redraw the systray
     if (systray_profile)
         fprintf(stderr,
                 BLUE "[%f] %s:%d trigger resize & redraw" RESET "\n",
                 profiling_get_time(),
-                __FUNCTION__,
+                __func__,
                 __LINE__);
     systray.area.resize_needed = TRUE;
     panel->area.resize_needed = TRUE;
@@ -770,7 +770,7 @@ gboolean reparent_icon(TrayWindow *traywin)
         fprintf(stderr,
                 "[%f] %s:%d win = %lu (%s)\n",
                 profiling_get_time(),
-                __FUNCTION__,
+                __func__,
                 __LINE__,
                 traywin->win,
                 traywin->name);
@@ -832,7 +832,7 @@ gboolean reparent_icon(TrayWindow *traywin)
         fprintf(stderr,
                 "[%f] %s:%d win = %lu (%s)\n",
                 profiling_get_time(),
-                __FUNCTION__,
+                __func__,
                 __LINE__,
                 traywin->win,
                 traywin->name);
@@ -846,7 +846,7 @@ gboolean embed_icon(TrayWindow *traywin)
         fprintf(stderr,
                 "[%f] %s:%d win = %lu (%s)\n",
                 profiling_get_time(),
-                __FUNCTION__,
+                __func__,
                 __LINE__,
                 traywin->win,
                 traywin->name);
@@ -903,7 +903,7 @@ gboolean embed_icon(TrayWindow *traywin)
         fprintf(stderr,
                 "[%f] %s:%d win = %lu (%s)\n",
                 profiling_get_time(),
-                __FUNCTION__,
+                __func__,
                 __LINE__,
                 traywin->win,
                 traywin->name);
@@ -917,7 +917,7 @@ void remove_icon(TrayWindow *traywin)
         fprintf(stderr,
                 "[%f] %s:%d win = %lu (%s)\n",
                 profiling_get_time(),
-                __FUNCTION__,
+                __func__,
                 __LINE__,
                 traywin->win,
                 traywin->name);
@@ -963,7 +963,7 @@ void remove_icon(TrayWindow *traywin)
         fprintf(stderr,
                 BLUE "[%f] %s:%d trigger resize & redraw" RESET "\n",
                 profiling_get_time(),
-                __FUNCTION__,
+                __func__,
                 __LINE__);
     systray.area.resize_needed = TRUE;
     panel->area.resize_needed = TRUE;
@@ -1086,7 +1086,7 @@ void systray_reconfigure_event(TrayWindow *traywin, XEvent *e)
         fprintf(stderr,
                 BLUE "[%f] %s:%d trigger resize & redraw" RESET "\n",
                 profiling_get_time(),
-                __FUNCTION__,
+                __func__,
                 __LINE__);
     schedule_panel_redraw();
     refresh_systray = TRUE;
@@ -1165,7 +1165,7 @@ void systray_resize_request_event(TrayWindow *traywin, XEvent *e)
         fprintf(stderr,
                 BLUE "[%f] %s:%d trigger resize & redraw" RESET "\n",
                 profiling_get_time(),
-                __FUNCTION__,
+                __func__,
                 __LINE__);
     schedule_panel_redraw();
     refresh_systray = TRUE;
@@ -1177,7 +1177,7 @@ void systray_destroy_event(TrayWindow *traywin)
         fprintf(stderr,
                 "[%f] %s:%d win = %lu (%s)\n",
                 profiling_get_time(),
-                __FUNCTION__,
+                __func__,
                 __LINE__,
                 traywin->win,
                 traywin->name);
@@ -1212,7 +1212,7 @@ void systray_render_icon_composited(void *t)
         fprintf(stderr,
                 "[%f] %s:%d win = %lu (%s)\n",
                 profiling_get_time(),
-                __FUNCTION__,
+                __func__,
                 __LINE__,
                 traywin->win,
                 traywin->name);
@@ -1230,7 +1230,7 @@ void systray_render_icon_composited(void *t)
                 fprintf(stderr,
                         YELLOW "[%f] %s:%d win = %lu (%s) delaying rendering" RESET "\n",
                         profiling_get_time(),
-                        __FUNCTION__,
+                        __func__,
                         __LINE__,
                         traywin->win,
                         traywin->name);
@@ -1250,7 +1250,7 @@ void systray_render_icon_composited(void *t)
             fprintf(stderr,
                     YELLOW "[%f] %s:%d win = %lu (%s) delaying rendering" RESET "\n",
                     profiling_get_time(),
-                    __FUNCTION__,
+                    __func__,
                     __LINE__,
                     traywin->win,
                     traywin->name);
@@ -1381,7 +1381,7 @@ void systray_render_icon_composited(void *t)
         fprintf(stderr,
                 "[%f] %s:%d win = %lu (%s)\n",
                 profiling_get_time(),
-                __FUNCTION__,
+                __func__,
                 __LINE__,
                 traywin->win,
                 traywin->name);
@@ -1419,7 +1419,7 @@ void systray_render_icon(void *t)
         //			fprintf(stderr,
         //			        YELLOW "[%f] %s:%d win = %lu (%s) delaying rendering" RESET "\n",
         //			        profiling_get_time(),
-        //			        __FUNCTION__,
+        //			        __func__,
         //			        __LINE__,
         //			        traywin->win,
         //			        traywin->name);
@@ -1433,7 +1433,7 @@ void systray_render_icon(void *t)
         fprintf(stderr,
                 "[%f] %s:%d win = %lu (%s)\n",
                 profiling_get_time(),
-                __FUNCTION__,
+                __func__,
                 __LINE__,
                 traywin->win,
                 traywin->name);
@@ -1466,7 +1466,7 @@ void systray_render_icon(void *t)
                     fprintf(stderr,
                             YELLOW "[%f] %s:%d win = %lu (%s) delaying rendering" RESET "\n",
                             profiling_get_time(),
-                            __FUNCTION__,
+                            __func__,
                             __LINE__,
                             traywin->win,
                             traywin->name);
@@ -1500,7 +1500,7 @@ void systray_render_icon(void *t)
 void refresh_systray_icons()
 {
     if (systray_profile)
-        fprintf(stderr, BLUE "tint2: [%f] %s:%d" RESET "\n", profiling_get_time(), __FUNCTION__, __LINE__);
+        fprintf(stderr, BLUE "tint2: [%f] %s:%d" RESET "\n", profiling_get_time(), __func__, __LINE__);
     TrayWindow *traywin;
     GSList *l;
     for (l = systray.list_icons; l; l = l->next) {
diff --git a/src/taskbar/task.c b/src/taskbar/task.c
index 75896dc..e05590c 100644
--- a/src/taskbar/task.c
+++ b/src/taskbar/task.c
@@ -93,7 +93,7 @@ Task *add_task(Window win)
              (int)win,
              task_template.title ? task_template.title : "null");
 
-    // fprintf(stderr, "tint2: %s %d: win = %ld, task = %s\n", __FUNCTION__, __LINE__, win, task_template.title ?
+    // fprintf(stderr, "tint2: %s %d: win = %ld, task = %s\n", __func__, __LINE__, win, task_template.title ?
     // task_template.title : "??");
     // fprintf(stderr, "tint2: new task %s win %u: desktop %d, monitor %d\n", new_task.title, win, new_task.desktop, monitor);
 
@@ -118,7 +118,7 @@ Task *add_task(Window win)
         task_instance->win_h = task_template.win_h;
         task_instance->current_state = TASK_UNDEFINED; // to update the current state later in set_task_state...
         if (task_instance->desktop == ALL_DESKTOPS && server.desktop != j) {
-            // fprintf(stderr, "tint2: %s %d: win = %ld hiding task: another desktop\n", __FUNCTION__, __LINE__, win);
+            // fprintf(stderr, "tint2: %s %d: win = %ld hiding task: another desktop\n", __func__, __LINE__, win);
             task_instance->area.on_screen = always_show_all_desktop_tasks;
         }
         task_instance->title = task_template.title;
@@ -186,7 +186,7 @@ void remove_task(Task *task)
     if (!task)
         return;
 
-    // fprintf(stderr, "tint2: %s %d: win = %ld, task = %s\n", __FUNCTION__, __LINE__, task->win, task->title ? task->title :
+    // fprintf(stderr, "tint2: %s %d: win = %ld, task = %s\n", __func__, __LINE__, task->win, task->title ? task->title :
     // "??");
 
     if (taskbar_mode == MULTI_DESKTOP) {
@@ -292,7 +292,7 @@ void task_update_icon(Task *task)
                     if (0 && img)
                         fprintf(stderr,
                                 "%s: Got %dx%d icon via _NET_WM_ICON for %s\n",
-                                __FUNCTION__,
+                                __func__,
                                 w,
                                 h,
                                 task->title ? task->title : "task");
@@ -318,7 +318,7 @@ void task_update_icon(Task *task)
                 if (0 && img)
                     fprintf(stderr,
                             "%s: Got %dx%d pixmap icon via WM_HINTS for %s\n",
-                            __FUNCTION__,
+                            __func__,
                             w,
                             h,
                             task->title ? task->title : "task");
@@ -783,7 +783,7 @@ void task_handle_mouse_event(Task *task, MouseAction action)
 
 void task_update_desktop(Task *task)
 {
-    // fprintf(stderr, "tint2: %s %d:\n", __FUNCTION__, __LINE__);
+    // fprintf(stderr, "tint2: %s %d:\n", __func__, __LINE__);
     Window win = task->win;
     remove_task(task);
     task = add_task(win);
diff --git a/src/taskbar/taskbar.c b/src/taskbar/taskbar.c
index 70ae6c9..3f91c45 100644
--- a/src/taskbar/taskbar.c
+++ b/src/taskbar/taskbar.c
@@ -467,7 +467,7 @@ void taskbar_refresh_tasklist()
 {
     if (!taskbar_enabled)
         return;
-    // fprintf(stderr, "tint2: %s %d:\n", __FUNCTION__, __LINE__);
+    // fprintf(stderr, "tint2: %s %d:\n", __func__, __LINE__);
 
     int num_results;
     Window *win = server_get_property(server.root_win, server.atom._NET_CLIENT_LIST, XA_WINDOW, &num_results);