diff --git a/library/common.h b/library/common.h
index de26d45..570b97e 100644
--- a/library/common.h
+++ b/library/common.h
@@ -335,24 +335,24 @@
 #endif
 
 /* Suppress compiler warnings for unused functions and variables. */
-#if !defined(MBEDTLS_MAYBE_UNUSED) && (defined(__GNUC__) || defined(__clang__))
-#define MBEDTLS_MAYBE_UNUSED __attribute__((unused))
+#if !defined(MBEDTLS_MAYBE_UNUSED) && defined(__has_attribute)
+#    if __has_attribute(unused)
+#        define MBEDTLS_MAYBE_UNUSED __attribute__((unused))
+#    endif
+#endif
+#if !defined(MBEDTLS_MAYBE_UNUSED) && defined(__GNUC__)
+#    define MBEDTLS_MAYBE_UNUSED __attribute__((unused))
 #endif
 #if !defined(MBEDTLS_MAYBE_UNUSED) && defined(__IAR_SYSTEMS_ICC__) && defined(__VER__)
-#if (__VER__ >= 8010000) // IAR 8.1 or later
-#define MBEDTLS_MAYBE_UNUSED __attribute__((unused))
-#endif
+#    if (__VER__ >= 8010000) // IAR 8.1 or later
+#        define MBEDTLS_MAYBE_UNUSED __attribute__((unused))
+#    endif
 #endif
 #if !defined(MBEDTLS_MAYBE_UNUSED) && defined(_MSC_VER)
-#define MBEDTLS_MAYBE_UNUSED __pragma(warning(suppress:4189))
-#endif
-#if !defined(MBEDTLS_MAYBE_UNUSED) && defined(__has_attribute)
-#if __has_attribute(unused)
-#define MBEDTLS_MAYBE_UNUSED __attribute__((unused))
-#endif
+#    define MBEDTLS_MAYBE_UNUSED __pragma(warning(suppress:4189))
 #endif
 #if !defined(MBEDTLS_MAYBE_UNUSED)
-#define MBEDTLS_MAYBE_UNUSED
+#    define MBEDTLS_MAYBE_UNUSED
 #endif
 
 #endif /* MBEDTLS_LIBRARY_COMMON_H */