diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index c98d78e..4f63bdb 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -30,6 +30,9 @@ jobs:
         - default
         - all
 
+    env:
+      RUSTFLAGS: "-D warnings"
+
     runs-on: ubuntu-latest
 
     steps:
diff --git a/src/backend/renderer/gles2/mod.rs b/src/backend/renderer/gles2/mod.rs
index 2c8342d..66af65d 100644
--- a/src/backend/renderer/gles2/mod.rs
+++ b/src/backend/renderer/gles2/mod.rs
@@ -26,7 +26,7 @@ use crate::backend::egl::{
     EGLContext, EGLSurface, MakeCurrentError,
 };
 use crate::backend::SwapBuffersError;
-use crate::utils::{Physical, Size};
+use crate::utils::{Buffer, Physical, Size};
 
 #[cfg(all(feature = "wayland_frontend", feature = "use_system_lib"))]
 use super::ImportEgl;
@@ -34,7 +34,8 @@ use super::ImportEgl;
 use super::{ImportDma, ImportShm};
 #[cfg(all(feature = "wayland_frontend", feature = "use_system_lib"))]
 use crate::backend::egl::{display::EGLBufferReader, Format as EGLFormat};
-use crate::utils::{Buffer, Rectangle};
+#[cfg(feature = "wayland_frontend")]
+use crate::utils::Rectangle;
 #[cfg(feature = "wayland_frontend")]
 use wayland_server::protocol::{wl_buffer, wl_shm};