M .gitignore → .gitignore

@@ -48,3 +48,6 @@ /testTexture
 /util/fluxbox-generate_menu
 /util/startfluxbox
 /version.h
+
+# off source build directory
+build

M src/SystemTray.cc → src/SystemTray.cc

@@ -599,8 +599,10 @@ TrayWindow *i) {
     // based on the parsed order list and a given window returns an
     // ordinal used to sort the tray icons.
 
-    std::unique_ptr<XClassHint, int(*)(void*)>
-        xclasshint(XAllocClassHint(), XFree);
+    auto deleter = [](XClassHint *x){if(x) XFree(x);};
+
+    std::unique_ptr<XClassHint, decltype(deleter)>
+        xclasshint(XAllocClassHint(), deleter);
 
     if(XGetClassHint(Fluxbox::instance()->display(),
                 i->window(), xclasshint.get()))