diff --git a/src/slic3r/GUI/GLCanvas3D.cpp b/src/slic3r/GUI/GLCanvas3D.cpp
index de912a1344..088451b79f 100644
--- a/src/slic3r/GUI/GLCanvas3D.cpp
+++ b/src/slic3r/GUI/GLCanvas3D.cpp
@@ -3471,10 +3471,10 @@ void GLCanvas3D::on_mouse(wxMouseEvent& evt)
         for (int hover_volume_id : m_hover_volume_idxs) { 
             const GLVolume &hover_gl_volume = *m_volumes.volumes[hover_volume_id];
             int object_idx = hover_gl_volume.object_idx();
-            if (object_idx < 0 || object_idx >= m_model->objects.size()) continue;
+            if (object_idx < 0 || static_cast<size_t>(object_idx) >= m_model->objects.size()) continue;
             const ModelObject* hover_object = m_model->objects[object_idx];
             int hover_volume_idx = hover_gl_volume.volume_idx();
-            if (hover_volume_idx < 0 || hover_volume_idx >= hover_object->volumes.size()) continue;
+            if (hover_volume_idx < 0 || static_cast<size_t>(hover_volume_idx) >= hover_object->volumes.size()) continue;
             const ModelVolume* hover_volume = hover_object->volumes[hover_volume_idx];
             if (!hover_volume->text_configuration.has_value()) continue;
             m_selection.add_volumes(Selection::EMode::Volume, {(unsigned) hover_volume_id});
diff --git a/src/slic3r/GUI/Gizmos/GLGizmoEmboss.cpp b/src/slic3r/GUI/Gizmos/GLGizmoEmboss.cpp
index 4e4ab5035d..ecbfd5a8c0 100644
--- a/src/slic3r/GUI/Gizmos/GLGizmoEmboss.cpp
+++ b/src/slic3r/GUI/Gizmos/GLGizmoEmboss.cpp
@@ -246,7 +246,7 @@ void GLGizmoEmboss::create_volume(ModelVolumeType volume_type)
     DataBase emboss_data = priv::create_emboss_data_base(m_text, m_style_manager);
     const ModelObjectPtrs &objects = selection.get_model()->objects;
     // No selected object so create new object
-    if (selection.is_empty() || object_idx < 0 || object_idx >= objects.size()) {
+    if (selection.is_empty() || object_idx < 0 || static_cast<size_t>(object_idx) >= objects.size()) {
         // create Object on center of screen
         // when ray throw center of screen not hit bed it create object on center of bed
         priv::start_create_object_job(emboss_data, screen_center);
@@ -3600,7 +3600,7 @@ bool priv::start_create_volume_on_surface_job(
     const ModelObjectPtrs &objects = plater->model().objects;
 
     int object_idx = gl_volume->object_idx();
-    if (object_idx < 0 ||  object_idx >= objects.size()) return false;
+    if (object_idx < 0 || static_cast<size_t>(object_idx) >= objects.size()) return false;
     ModelObject *obj = objects[object_idx];
     size_t vol_id = obj->volumes[gl_volume->volume_idx()]->id().id;
     auto cond = RaycastManager::AllowVolumes({vol_id});