diff --git a/lib/atca_iface.c b/lib/atca_iface.c
index 84f75960f..051fcc10a 100644
--- a/lib/atca_iface.c
+++ b/lib/atca_iface.c
@@ -441,6 +441,7 @@ uint8_t ifacecfg_get_address(ATCAIfaceCfg * cfg)
         {
 #ifdef ATCA_HAL_I2C
         case ATCA_I2C_IFACE:
+            UNUSED(kitiface);
 #ifdef ATCA_ENABLE_DEPRECATED
             addr = ATCA_IFACECFG_VALUE(cfg, atcai2c.slave_address);
 #else
diff --git a/lib/cryptoauthlib.h b/lib/cryptoauthlib.h
index aaca7a6ae..bab8eadf8 100644
--- a/lib/cryptoauthlib.h
+++ b/lib/cryptoauthlib.h
@@ -49,6 +49,10 @@
 #include "atca_helpers.h"
 #include "hal/atca_hal.h"
 
+#ifndef UNUSED
+#define UNUSED(X) (void)X /* To avoid gcc/g++ "unused-parameter" warnings */
+#endif
+
 /* Common Cryptographic Definitions */
 #define ATCA_SHA256_BLOCK_SIZE              (64u)
 #define ATCA_SHA256_DIGEST_SIZE             (32u)
diff --git a/lib/mbedtls/atca_mbedtls_ecdh.c b/lib/mbedtls/atca_mbedtls_ecdh.c
index 952da581f..a37a82e0e 100644
--- a/lib/mbedtls/atca_mbedtls_ecdh.c
+++ b/lib/mbedtls/atca_mbedtls_ecdh.c
@@ -50,6 +50,9 @@ int mbedtls_ecdh_gen_public(mbedtls_ecp_group *grp, mbedtls_mpi *d, mbedtls_ecp_
                             int (*f_rng)(void *, unsigned char *, size_t),
                             void *p_rng)
 {
+    UNUSED(f_rng);
+    UNUSED(p_rng);
+
     int ret = 0;
     uint8_t public_key[ATCA_PUB_KEY_SIZE];
     uint8_t temp = 1;
@@ -103,6 +106,8 @@ int mbedtls_ecdh_compute_shared(mbedtls_ecp_group *grp, mbedtls_mpi *z,
                                 int (*f_rng)(void *, unsigned char *, size_t),
                                 void *p_rng)
 {
+    UNUSED(f_rng);
+    UNUSED(p_rng);
 
     int ret = 0;
     uint8_t public_key[ATCA_PUB_KEY_SIZE];
diff --git a/lib/pkcs11/pkcs11_key.c b/lib/pkcs11/pkcs11_key.c
index 383c6db77..e7e027a6a 100644
--- a/lib/pkcs11/pkcs11_key.c
+++ b/lib/pkcs11/pkcs11_key.c
@@ -2234,7 +2234,7 @@ static uint8_t pkcs11_key_used(uint8_t * key, size_t keylen)
 {
     if (key)
     {
-        for (int i = 0; i < keylen; i++)
+        for (uint8_t i = 0; i < keylen; i++)
         {
             if (key[i])
             {
diff --git a/lib/pkcs11/pkcs11_slot.c b/lib/pkcs11/pkcs11_slot.c
index 85dc324a0..fdc11f72b 100644
--- a/lib/pkcs11/pkcs11_slot.c
+++ b/lib/pkcs11/pkcs11_slot.c
@@ -103,6 +103,7 @@ pkcs11_slot_ctx_ptr pkcs11_slot_get_new_context(pkcs11_lib_ctx_ptr lib_ctx)
 CK_VOID_PTR pkcs11_slot_initslots(CK_ULONG pulCount)
 {
 #ifdef ATCA_NO_HEAP
+	UNUSED(pulCount);
     int i;
     for (i = 0; i < PKCS11_MAX_SLOTS_ALLOWED; i++)
     {