diff --git a/library/common.h b/library/common.h
index c20f6b2..78d71fd 100644
--- a/library/common.h
+++ b/library/common.h
@@ -169,7 +169,9 @@
 {
     size_t i = 0;
 #if defined(MBEDTLS_EFFICIENT_UNALIGNED_ACCESS)
-#if defined(__ARM_NEON)
+#if defined(__ARM_NEON) && \
+    (defined(__GNUC__) && !defined(__clang__) && \
+    __GNUC__ >= 7 && __GNUC_MINOR__ >= 3)
     for (; (i + 16) <= n; i += 16) {
         uint8x16_t v1 = vld1q_u8(a + i);
         uint8x16_t v2 = vld1q_u8(b + i);