diff --git a/library/common.h b/library/common.h
index e502b5de13..3925a79ce5 100644
--- a/library/common.h
+++ b/library/common.h
@@ -73,11 +73,12 @@ extern void (*mbedtls_test_hook_test_fail)( const char * test, int line, const c
  *
  * This list is incomplete.
  */
-#if defined(__i386__) || defined(__amd64__) || defined( __x86_64__) \
+#if (defined(__i386__) || defined(__amd64__) || defined( __x86_64__) \
     || defined(__ARM_FEATURE_UNALIGNED) \
     || defined(__aarch64__) \
     || defined(__ARM_ARCH_8__) || defined(__ARM_ARCH_8A__) || defined(__ARM_ARCH_8M__) \
-    || defined(__ARM_ARCH_7A__)
+    || defined(__ARM_ARCH_7A__)) \
+    && (!(defined(__has_feature) && __has_feature(undefined_behavior_sanitizer)))
 #define MBEDTLS_ALLOW_UNALIGNED_ACCESS
 #endif