diff --git a/gstreamer-video/src/video_info.rs b/gstreamer-video/src/video_info.rs
index 9101c68e0..dc6d889f8 100644
--- a/gstreamer-video/src/video_info.rs
+++ b/gstreamer-video/src/video_info.rs
@@ -1396,8 +1396,8 @@ mod tests {
     fn test_display() {
         gst::init().unwrap();
 
-        format!("{}", "sRGB".parse::<crate::VideoColorimetry>().unwrap());
-        format!("{}", crate::VideoFieldOrder::TopFieldFirst);
-        format!("{}", crate::VideoInterlaceMode::Progressive);
+        let _ = format!("{}", "sRGB".parse::<crate::VideoColorimetry>().unwrap());
+        let _ = format!("{}", crate::VideoFieldOrder::TopFieldFirst);
+        let _ = format!("{}", crate::VideoInterlaceMode::Progressive);
     }
 }
diff --git a/gstreamer/src/caps.rs b/gstreamer/src/caps.rs
index 70856c890..cd01816a4 100644
--- a/gstreamer/src/caps.rs
+++ b/gstreamer/src/caps.rs
@@ -1317,7 +1317,7 @@ mod tests {
         crate::init().unwrap();
 
         let caps = Caps::builder("foo/bar").build();
-        format!("{caps}");
+        let _ = format!("{caps}");
     }
 
     #[test]
diff --git a/gstreamer/src/tags.rs b/gstreamer/src/tags.rs
index 6a46c63b3..7805712be 100644
--- a/gstreamer/src/tags.rs
+++ b/gstreamer/src/tags.rs
@@ -1355,7 +1355,7 @@ mod tests {
     fn test_display() {
         crate::init().unwrap();
 
-        format!("{}", TagList::new());
+        let _ = format!("{}", TagList::new());
     }
 
     #[test]
diff --git a/gstreamer/src/utils.rs b/gstreamer/src/utils.rs
index bd77358b1..f929c25c2 100644
--- a/gstreamer/src/utils.rs
+++ b/gstreamer/src/utils.rs
@@ -18,7 +18,7 @@ pub struct ObjectLockGuard<'a, T: ?Sized> {
 
 impl<'a, T> ObjectLockGuard<'a, T>
 where
-    T: IsA<crate::Object> + ?Sized,
+    T: IsA<crate::Object>,
 {
     #[inline]
     pub fn acquire(obj: &'a T) -> ObjectLockGuard<'a, T> {