diff --git a/sys/kerncore/src/lib.rs b/sys/kerncore/src/lib.rs
index f7657b22ea..1fddd5d1b9 100644
--- a/sys/kerncore/src/lib.rs
+++ b/sys/kerncore/src/lib.rs
@@ -152,6 +152,8 @@ impl<T: MemoryRegion> MemoryRegion for &T {
 /// that meet the `region_ok` condition.
 ///
 /// `false` otherwise.
+#[must_use]
+#[inline(always)]
 pub fn can_access<S, R>(
     slice: S,
     table: &[R],