The SIGC weirdness should now work on all platforms.

src/directories.cc

@@ -8,8 +8,8 @@
 #include <iostream> //TODO: remove
 using namespace std; //TODO: remove
 
-#ifndef _WIN32
 namespace sigc {
+#ifndef SIGC_FUNCTORS_DEDUCE_RESULT_TYPE_WITH_DECLTYPE
   template <typename Functor>
   struct functor_trait<Functor, false> {
     typedef decltype (::sigc::mem_fun(std::declval<Functor&>(),
@@ -17,8 +17,10 @@ namespace sigc {
     typedef typename _intermediate::result_type result_type;
     typedef Functor functor_type;
   };
-}
+#else
+  SIGC_FUNCTORS_DEDUCE_RESULT_TYPE_WITH_DECLTYPE
 #endif
+}
 
 Directories::Directories() : stop_update_thread(false) {
   DEBUG("adding treeview to scrolledwindow");

src/entrybox.cc

@@ -1,7 +1,7 @@
 #include "entrybox.h"
 
-#ifndef _WIN32
 namespace sigc {
+#ifndef SIGC_FUNCTORS_DEDUCE_RESULT_TYPE_WITH_DECLTYPE
   template <typename Functor>
   struct functor_trait<Functor, false> {
     typedef decltype (::sigc::mem_fun(std::declval<Functor&>(),
@@ -9,8 +9,10 @@ namespace sigc {
     typedef typename _intermediate::result_type result_type;
     typedef Functor functor_type;
   };
-}
+#else
+  SIGC_FUNCTORS_DEDUCE_RESULT_TYPE_WITH_DECLTYPE
 #endif
+}
 
 std::unordered_map<std::string, std::vector<std::string> > EntryBox::entry_histories;
 

src/notebook.cc

@@ -9,8 +9,8 @@
 #include <iostream> //TODO: remove
 using namespace std; //TODO: remove
 
-#ifndef _WIN32
 namespace sigc {
+#ifndef SIGC_FUNCTORS_DEDUCE_RESULT_TYPE_WITH_DECLTYPE
   template <typename Functor>
   struct functor_trait<Functor, false> {
     typedef decltype (::sigc::mem_fun(std::declval<Functor&>(),
@@ -18,8 +18,10 @@ namespace sigc {
     typedef typename _intermediate::result_type result_type;
     typedef Functor functor_type;
   };
-}
+#else
+  SIGC_FUNCTORS_DEDUCE_RESULT_TYPE_WITH_DECLTYPE
 #endif
+}
 
 Notebook::Notebook(Directories &directories) : Gtk::Notebook(), directories(directories) {
   Gsv::init();

src/selectiondialog.cc

@@ -1,8 +1,8 @@
 #include "selectiondialog.h"
 #include <algorithm>
 
-#ifndef _WIN32
 namespace sigc {
+#ifndef SIGC_FUNCTORS_DEDUCE_RESULT_TYPE_WITH_DECLTYPE
   template <typename Functor>
   struct functor_trait<Functor, false> {
     typedef decltype (::sigc::mem_fun(std::declval<Functor&>(),
@@ -10,8 +10,10 @@ namespace sigc {
     typedef typename _intermediate::result_type result_type;
     typedef Functor functor_type;
   };
-}
+#else
+  SIGC_FUNCTORS_DEDUCE_RESULT_TYPE_WITH_DECLTYPE
 #endif
+}
 
 SelectionDialogBase::SelectionDialogBase(Gtk::TextView& text_view, Glib::RefPtr<Gtk::TextBuffer::Mark> start_mark, bool show_search_entry): text_view(text_view), 
 start_mark(start_mark), show_search_entry(show_search_entry), list_view_text(1, false, Gtk::SelectionMode::SELECTION_BROWSE) {

src/source.cc

@@ -11,8 +11,8 @@
 
 using namespace std; //TODO: remove
 
-#ifndef _WIN32
 namespace sigc {
+#ifndef SIGC_FUNCTORS_DEDUCE_RESULT_TYPE_WITH_DECLTYPE
   template <typename Functor>
   struct functor_trait<Functor, false> {
     typedef decltype (::sigc::mem_fun(std::declval<Functor&>(),
@@ -20,8 +20,10 @@ namespace sigc {
     typedef typename _intermediate::result_type result_type;
     typedef Functor functor_type;
   };
-}
+#else
+  SIGC_FUNCTORS_DEDUCE_RESULT_TYPE_WITH_DECLTYPE
 #endif
+}
 
 Glib::RefPtr<Gsv::Language> Source::guess_language(const boost::filesystem::path &file_path) {
   auto language_manager=Gsv::LanguageManager::get_default();

src/tooltips.cc

@@ -1,8 +1,8 @@
 #include "tooltips.h"
 #include "singletons.h"
 
-#ifndef _WIN32
 namespace sigc {
+#ifndef SIGC_FUNCTORS_DEDUCE_RESULT_TYPE_WITH_DECLTYPE
   template <typename Functor>
   struct functor_trait<Functor, false> {
     typedef decltype (::sigc::mem_fun(std::declval<Functor&>(),
@@ -10,8 +10,10 @@ namespace sigc {
     typedef typename _intermediate::result_type result_type;
     typedef Functor functor_type;
   };
-}
+#else
+  SIGC_FUNCTORS_DEDUCE_RESULT_TYPE_WITH_DECLTYPE
 #endif
+}
 
 Gdk::Rectangle Tooltips::drawn_tooltips_rectangle=Gdk::Rectangle();
 

src/window.cc

@@ -9,8 +9,8 @@
 #include <iostream> //TODO: remove
 using namespace std; //TODO: remove
 
-#ifndef _WIN32
 namespace sigc {
+#ifndef SIGC_FUNCTORS_DEDUCE_RESULT_TYPE_WITH_DECLTYPE
   template <typename Functor>
   struct functor_trait<Functor, false> {
     typedef decltype (::sigc::mem_fun(std::declval<Functor&>(),
@@ -18,8 +18,10 @@ namespace sigc {
     typedef typename _intermediate::result_type result_type;
     typedef Functor functor_type;
   };
-}
+#else
+  SIGC_FUNCTORS_DEDUCE_RESULT_TYPE_WITH_DECLTYPE
 #endif
+}
 
 void Window::generate_keybindings() {
   boost::filesystem::path path(Singleton::config_dir() + "menu.xml");