diff --git a/sys/include/xtimer/implementation.h b/sys/include/xtimer/implementation.h
index 4190260efc..107ac99e91 100644
--- a/sys/include/xtimer/implementation.h
+++ b/sys/include/xtimer/implementation.h
@@ -51,6 +51,8 @@ static inline uint32_t _xtimer_lltimer_now(void)
  */
 static inline uint32_t _xtimer_lltimer_mask(uint32_t val)
 {
+    /* cppcheck-suppress shiftTooManyBits
+     * (reason: cppcheck bug. `XTIMER_MASK` is zero when `XTIMER_WIDTH` is 32) */
     return val & ~XTIMER_MASK;
 }