diff --git a/tinycrypt/ecc_dh.c b/tinycrypt/ecc_dh.c
index 54b9a8a..8199210 100644
--- a/tinycrypt/ecc_dh.c
+++ b/tinycrypt/ecc_dh.c
@@ -88,7 +88,7 @@
 	/* This function is designed for test purposes-only (such as validating NIST
 	 * test vectors) as it uses a provided value for d instead of generating
 	 * it uniformly at random. */
-	memcpy (_private, d, NUM_ECC_BYTES);
+	mbedtls_platform_memcpy (_private, d, NUM_ECC_BYTES);
 
 	/* Computing public-key from private: */
 	if (EccPoint_compute_public_key(_public, _private, curve)) {