Cross-thread lambda functions fail on win32

src/canvas.cpp

@@ -41,6 +41,12 @@ void Canvas::set_status(const QString &s)
     update();
 }
 
+void Canvas::clear_status()
+{
+    status = "";
+    update();
+}
+
 void Canvas::initializeGL()
 {
     mesh_shader.addShaderFromSourceFile(QGLShader::Vertex, ":/gl/mesh.vert");

src/canvas.h

@@ -23,6 +23,7 @@ public:
 
 public slots:
     void set_status(const QString& s);
+    void clear_status();
     void load_mesh(Mesh* m);
 
 

src/window.cpp

@@ -69,6 +69,16 @@ void Window::on_about()
         "   style=\"color: #93a1a1;\">matt.j.keeter@gmail.com</a></p>");
 }
 
+void Window::enable_open()
+{
+    open_action->setEnabled(true);
+}
+
+void Window::disable_open()
+{
+    open_action->setEnabled(false);
+}
+
 bool Window::load_stl(const QString& filename)
 {
     if (!open_action->isEnabled())  return false;
@@ -77,7 +87,7 @@ bool Window::load_stl(const QString& filename)
 
     Loader* loader = new Loader(this, filename);
     connect(loader, &Loader::started,
-            [=](){ open_action->setEnabled(false); });
+              this, &Window::disable_open);
 
     connect(loader, &Loader::got_mesh,
             canvas, &Canvas::load_mesh);
@@ -85,9 +95,9 @@ bool Window::load_stl(const QString& filename)
     connect(loader, &Loader::finished,
             loader, &Loader::deleteLater);
     connect(loader, &Loader::finished,
-            [=](){ open_action->setEnabled(true); });
+              this, &Window::enable_open);
     connect(loader, &Loader::finished,
-            [=](){ canvas->set_status(""); });
+            canvas, &Canvas::clear_status);
 
     if (filename[0] != ':')
     {

src/window.h

@@ -16,6 +16,9 @@ public slots:
     void on_open();
     void on_about();
 
+    void enable_open();
+    void disable_open();
+
 private:
     QAction* const open_action;
     QAction* const about_action;