Fixed several warnings

src/libslic3r/Arrange.cpp

@@ -750,7 +750,7 @@ void arrange(ArrangePolygons &items,
         d += corr;
 
         for (auto &itm : items)
-            if (itm.bed_idx == bedidx)
+            if (itm.bed_idx == int(bedidx))
                 itm.translation += d;
     }
 }

src/libslic3r/GCode.cpp

@@ -2450,7 +2450,7 @@ void GCode::process_layer_single_object(
         int extruder_override_id = is_anything_overridden ? layer_tools.wiping_extrusions().get_extruder_override(eec, instance_id) : -1;
         return print_wipe_extrusions ?
             extruder_override_id == int(extruder_id) :
-            extruder_override_id < 0 && extruder_id == correct_extruder_id;
+            extruder_override_id < 0 && int(extruder_id) == correct_extruder_id;
     };
 
     ExtrusionEntitiesPtr temp_fill_extrusions;

src/libslic3r/GCode/WipeTower.cpp

@@ -581,7 +581,7 @@ void WipeTower::set_extruder(size_t idx, const PrintConfig& config)
     m_filpar.push_back(FilamentParameters());
 
     m_filpar[idx].material = config.filament_type.get_at(idx);
-    m_filpar[idx].is_soluble = config.wipe_tower_extruder == 0 ? config.filament_soluble.get_at(idx) : (idx != config.wipe_tower_extruder - 1);
+    m_filpar[idx].is_soluble = config.wipe_tower_extruder == 0 ? config.filament_soluble.get_at(idx) : (idx != size_t(config.wipe_tower_extruder - 1));
     m_filpar[idx].temperature = config.temperature.get_at(idx);
     m_filpar[idx].first_layer_temperature = config.first_layer_temperature.get_at(idx);
 
@@ -1292,7 +1292,6 @@ WipeTower::ToolChangeResult WipeTower::finish_layer()
 
     // brim (first layer only)
     if (first_layer) {
-        box_coordinates box = wt_box;
         size_t loops_num = (m_wipe_tower_brim_width + spacing/2.f) / spacing;
         
         for (size_t i = 0; i < loops_num; ++ i) {

src/slic3r/GUI/Gizmos/GLGizmosCommon.cpp

@@ -391,7 +391,7 @@ void ObjectClipper::render_cut(const std::vector<size_t>* ignore_idxs) const
         // Now update the ignore idxs. Find the first element belonging to the next clipper,
         // and remove everything before it and decrement everything by current number of contours.
         const int num_of_contours = clipper.first->get_number_of_contours();
-        ignore_idxs_local.erase(ignore_idxs_local.begin(), std::find_if(ignore_idxs_local.begin(), ignore_idxs_local.end(), [num_of_contours](size_t idx) { return idx >= num_of_contours; } ));
+        ignore_idxs_local.erase(ignore_idxs_local.begin(), std::find_if(ignore_idxs_local.begin(), ignore_idxs_local.end(), [num_of_contours](size_t idx) { return idx >= size_t(num_of_contours); } ));
         for (size_t& idx : ignore_idxs_local)
             idx -= num_of_contours;
     }

src/slic3r/GUI/Plater.cpp

@@ -6099,7 +6099,7 @@ void Plater::increase_instances(size_t num, int obj_idx, int inst_idx)
             if (const auto obj_idxs = get_selection().get_object_idxs(); !obj_idxs.empty()) {
                 // we need a copy made here because the selection changes at every call of increase_instances()
                 const Selection::ObjectIdxsToInstanceIdxsMap content = p->get_selection().get_content();
-                for (const size_t& obj_id : obj_idxs) {
+                for (const unsigned int obj_id : obj_idxs) {
                     if (auto obj_it = content.find(int(obj_id)); obj_it != content.end())
                         increase_instances(1, int(obj_id), *obj_it->second.rbegin());
                 }