Fix some errors uncovered via compiler warnings (SoftFever#7954)

* fix: tray_exist_bits != tray_exist_bits comparison

* fix: title == GetTitle() == title comparison

* fix: possibly dangling reference to a temporary
```
OrcaSlicer/src/libslic3r/calib.cpp:456:17: warning: possibly dangling reference to a temporary [-Wdangling-reference]
  456 |     const auto &w         = bed_ext.size().x();
OrcaSlicer/src/libslic3r/calib.cpp:456:45: note: the temporary was destroyed at the end of the full expression ‘((Eigen::DenseCoeffsBase<Eigen::Matrix<double, 2, 1, 2>, 1>*)(& Slic3r::BoundingBoxBase<PointClass>::size() const [with PointClass = Eigen::Matrix<double, 2, 1, 2>]()))->Eigen::DenseCoeffsBase<Eigen::Matrix<double, 2, 1, 2>, 1>::x()’
  456 |     const auto &w         = bed_ext.size().x();
```

* fix: mixup of | and ||
in this case I think it actually does not change the semantics it just means that both comparison have to be evaluated.

* fix: multi-character character constants need "

OrcaSlicer/src/slic3r/GUI/MediaPlayCtrl.cpp:392: warning: multi-character character constant [-Wmultichar]
  392 |     if (auto n = tunnel.find_first_of('/_'); n != std::string::npos)
OrcaSlicer/src/slic3r/GUI/MediaPlayCtrl.cpp: In member function ‘void Slic3r::GUI::MediaPlayCtrl::Stop(const wxString&)’:
OrcaSlicer/src/slic3r/GUI/MediaPlayCtrl.cpp:392: warning: overflow in conversion from ‘int’ to ‘char’ changes value from ‘12127’ to ‘95’ [-Woverflow]

* fix: missing paranthesis - skips null check

* NFC: Remove this check it can never be false

* NFC: fix warning: statement has no effect

src/libslic3r/Support/TreeSupport.cpp

@@ -2380,7 +2380,7 @@ void TreeSupport::draw_circles(const std::vector<std::vector<Node*>>& contact_no
                 ExPolygons& base_areas = ts_layer->base_areas;
 
                 int layer_nr_lower = layer_nr - 1;
-                for (layer_nr_lower; layer_nr_lower >= 0; layer_nr_lower--) {
+                for (; layer_nr_lower >= 0; layer_nr_lower--) {
                     if (!m_object->get_support_layer(layer_nr_lower + m_raft_layers)->area_groups.empty()) break;
                 }
                 if (layer_nr_lower <= 0) continue;
@@ -2470,7 +2470,7 @@ void TreeSupport::draw_circles(const std::vector<std::vector<Node*>>& contact_no
                 if (ts_layer->area_groups.empty()) continue;
 
                 int layer_nr_lower = layer_nr - 1;
-                for (layer_nr_lower; layer_nr_lower >= 0; layer_nr_lower--) {
+                for (; layer_nr_lower >= 0; layer_nr_lower--) {
                     if (!m_object->get_support_layer(layer_nr_lower + m_raft_layers)->area_groups.empty()) break;
                 }
                 if (layer_nr_lower < 0) continue;

src/libslic3r/calib.cpp

@@ -453,8 +453,8 @@ std::string CalibPressureAdvanceLine::generate_test(double start_pa /*= 0*/, dou
     }
 
     auto        bed_sizes = mp_gcodegen->config().printable_area.values;
-    const auto &w         = bed_ext.size().x();
-    const auto &h         = bed_ext.size().y();
+    const auto  w         = bed_ext.size().x();
+    const auto  h         = bed_ext.size().y();
     count                 = std::min(count, int((h - 10) / m_space_y));
 
     m_length_long = 40 + std::min(w - 120.0, 0.0);

src/slic3r/GUI/DeviceManager.cpp

@@ -3873,10 +3873,10 @@ int MachineObject::parse_json(std::string payload, bool key_field_only)
                                     }
                                 }
                                 if (ams_exist_bits != last_ams_exist_bits
-                                    || last_tray_exist_bits != last_tray_exist_bits
+                                    || tray_exist_bits != last_tray_exist_bits
                                     || tray_is_bbl_bits != last_is_bbl_bits
                                     || tray_read_done_bits != last_read_done_bits
-                                    || last_ams_version != ams_version) {
+                                    || ams_version != last_ams_version) {
                                     is_ams_need_update = true;
                                 }
                                 else {

src/slic3r/GUI/Gizmos/GLGizmosManager.cpp

@@ -915,7 +915,7 @@ bool GLGizmosManager::on_key(wxKeyEvent& evt)
         }
         else if (m_current == FdmSupports) {
             GLGizmoFdmSupports* fdm_support = dynamic_cast<GLGizmoFdmSupports*>(get_current());
-            if (fdm_support != nullptr && keyCode == 'F' || keyCode == 'S' || keyCode == 'C' || keyCode == 'G') {
+            if (fdm_support != nullptr && (keyCode == 'F' || keyCode == 'S' || keyCode == 'C' || keyCode == 'G')) {
                 processed = fdm_support->on_key_down_select_tool_type(keyCode);
             }
             if (processed) {
@@ -925,7 +925,7 @@ bool GLGizmosManager::on_key(wxKeyEvent& evt)
         }
         else if (m_current == Seam) {
             GLGizmoSeam* seam = dynamic_cast<GLGizmoSeam*>(get_current());
-            if (seam != nullptr && keyCode == 'S' || keyCode == 'C') {
+            if (seam != nullptr && (keyCode == 'S' || keyCode == 'C')) {
                 processed = seam->on_key_down_select_tool_type(keyCode);
             }
             if (processed) {

src/slic3r/GUI/Jobs/PrintJob.cpp

@@ -47,12 +47,10 @@ void PrintJob::prepare()
 {
     if (job_data.is_from_plater)
         m_plater->get_print_job_data(&job_data);
-    if (&job_data) {
-        std::string temp_file = Slic3r::resources_dir() + "/check_access_code.txt";
-        auto check_access_code_path = temp_file.c_str();
-        BOOST_LOG_TRIVIAL(trace) << "sned_job: check_access_code_path = " << check_access_code_path;
-        job_data._temp_path = fs::path(check_access_code_path);
-    }
+    std::string temp_file = Slic3r::resources_dir() + "/check_access_code.txt";
+    auto check_access_code_path = temp_file.c_str();
+    BOOST_LOG_TRIVIAL(trace) << "sned_job: check_access_code_path = " << check_access_code_path;
+    job_data._temp_path = fs::path(check_access_code_path);
 }
 
 void PrintJob::on_success(std::function<void()> success)

src/slic3r/GUI/Jobs/SendJob.cpp

@@ -38,12 +38,10 @@ SendJob::SendJob(std::string dev_id)
 void SendJob::prepare()
 {
     m_plater->get_print_job_data(&job_data);
-    if (&job_data) {
-        std::string temp_file = Slic3r::resources_dir() + "/check_access_code.txt";
-        auto check_access_code_path = temp_file.c_str();
-        BOOST_LOG_TRIVIAL(trace) << "sned_job: check_access_code_path = " << check_access_code_path;
-        job_data._temp_path = fs::path(check_access_code_path);
-    }
+    std::string temp_file = Slic3r::resources_dir() + "/check_access_code.txt";
+    auto check_access_code_path = temp_file.c_str();
+    BOOST_LOG_TRIVIAL(trace) << "sned_job: check_access_code_path = " << check_access_code_path;
+    job_data._temp_path = fs::path(check_access_code_path);
 }
 
 wxString SendJob::get_http_error_msg(unsigned int status, std::string body)

src/slic3r/GUI/MainFrame.cpp

@@ -916,7 +916,6 @@ void MainFrame::update_title_colour_after_set_title()
 
 void MainFrame::show_option(bool show)
 {
-    if (!this) { return; }
     if (!show) {
         if (m_slice_btn->IsShown()) {
             m_slice_btn->Hide();

src/slic3r/GUI/MediaPlayCtrl.cpp

@@ -389,7 +389,7 @@ void MediaPlayCtrl::Stop(wxString const &msg)
     }
 
     auto tunnel = m_url.empty() ? "" : into_u8(wxURI(m_url).GetPath()).substr(1);
-    if (auto n = tunnel.find_first_of('/_'); n != std::string::npos)
+    if (auto n = tunnel.find_first_of("/_"); n != std::string::npos)
         tunnel = tunnel.substr(0, n);
     if (last_state != wxMEDIASTATE_PLAYING && m_failed_code != 0 
             && m_last_failed_codes.find(m_failed_code) == m_last_failed_codes.end()

src/slic3r/GUI/ReleaseNote.cpp

@@ -786,7 +786,7 @@ void SecondaryCheckDialog::on_hide()
 
 void SecondaryCheckDialog::update_title_style(wxString title, SecondaryCheckDialog::ButtonStyle style, wxWindow* parent)
 {
-    if (m_button_style == style && title == GetTitle() == title) return;
+    if (m_button_style == style && title == GetTitle()) return;
 
     SetTitle(title);
 

src/slic3r/GUI/SendMultiMachinePage.cpp

@@ -473,12 +473,10 @@ BBL::PrintParams SendMultiMachinePage::request_params(MachineObject* obj)
     PrintPrepareData job_data;
     m_plater->get_print_job_data(&job_data);
 
-    if (&job_data) {
-        std::string temp_file = Slic3r::resources_dir() + "/check_access_code.txt";
-        auto check_access_code_path = temp_file.c_str();
-        BOOST_LOG_TRIVIAL(trace) << "sned_job: check_access_code_path = " << check_access_code_path;
-        job_data._temp_path = fs::path(check_access_code_path);
-    }
+    std::string temp_file = Slic3r::resources_dir() + "/check_access_code.txt";
+    auto check_access_code_path = temp_file.c_str();
+    BOOST_LOG_TRIVIAL(trace) << "sned_job: check_access_code_path = " << check_access_code_path;
+    job_data._temp_path = fs::path(check_access_code_path);
 
     int curr_plate_idx;
     if (job_data.plate_idx >= 0)

src/slic3r/GUI/Tab.cpp

@@ -881,7 +881,7 @@ void TabPrinter::init_options_list()
 
     for (const std::string& opt_key : m_config->keys())
     {
-        if (opt_key == "printable_area" || opt_key == "bed_exclude_area" | opt_key == "thumbnails") {
+        if (opt_key == "printable_area" || opt_key == "bed_exclude_area" || opt_key == "thumbnails") {
             m_options_list.emplace(opt_key, m_opt_status_value);
             continue;
         }

src/slic3r/Utils/UndoRedo.cpp

@@ -1071,7 +1071,7 @@ bool StackImpl::has_redo_snapshot() const
 
 	// BBS: undo-redo until modify record
 	auto it = std::lower_bound(m_snapshots.begin(), m_snapshots.end(), Snapshot(m_active_snapshot_time));
-	for (it; it != m_snapshots.end(); ++it) {
+	for (; it != m_snapshots.end(); ++it) {
 		if (snapshot_modifies_project(*it))
 			return true;
 	}
@@ -1340,12 +1340,12 @@ bool StackImpl::has_real_change_from(size_t time) const
                                       Snapshot(m_active_snapshot_time));
     if (it_active == m_snapshots.end()) return true;
     if (it_active > it_time) {
-        for (it_time; it_time < it_active; ++it_time) {
+        for (; it_time < it_active; ++it_time) {
             if (snapshot_modifies_project(*it_time))
                 return true;
 		}
     } else {
-        for (it_active; it_active < it_time; ++it_active) {
+        for (; it_active < it_time; ++it_active) {
             if (snapshot_modifies_project(*it_active))
                 return true;
         }