diff --git a/library/psa_crypto_aead.c b/library/psa_crypto_aead.c
index 03327f2..c181415 100644
--- a/library/psa_crypto_aead.c
+++ b/library/psa_crypto_aead.c
@@ -119,6 +119,8 @@
 #endif /* MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305 */
 
         default:
+            (void) status;
+            (void) key_buffer;
             return( PSA_ERROR_NOT_SUPPORTED );
     }
 
@@ -214,6 +216,11 @@
 #endif /* MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305 */
     {
         (void) tag;
+        (void) nonce;
+        (void) nonce_length;
+        (void) additional_data;
+        (void) additional_data_length;
+        (void) plaintext;
         return( PSA_ERROR_NOT_SUPPORTED );
     }
 
@@ -321,6 +328,11 @@
     else
 #endif /* MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305 */
     {
+        (void) nonce;
+        (void) nonce_length;
+        (void) additional_data;
+        (void) additional_data_length;
+        (void) plaintext;
         return( PSA_ERROR_NOT_SUPPORTED );
     }
 
diff --git a/library/psa_crypto_driver_wrappers.c b/library/psa_crypto_driver_wrappers.c
index 992b7a7..d6e5778 100644
--- a/library/psa_crypto_driver_wrappers.c
+++ b/library/psa_crypto_driver_wrappers.c
@@ -1059,6 +1059,7 @@
         default:
             /* Key is declared with a lifetime not known to us */
             (void)status;
+            (void)operation;
             (void)key_buffer;
             (void)key_buffer_size;
             (void)alg;
@@ -2077,6 +2078,7 @@
         default:
             /* Key is declared with a lifetime not known to us */
             (void) status;
+            (void) operation;
             (void) key_buffer;
             (void) key_buffer_size;
             (void) alg;
@@ -2148,6 +2150,7 @@
         default:
             /* Key is declared with a lifetime not known to us */
             (void) status;
+            (void) operation;
             (void) key_buffer;
             (void) key_buffer_size;
             (void) alg;
diff --git a/library/psa_crypto_mac.c b/library/psa_crypto_mac.c
index d59178e..421d12e 100644
--- a/library/psa_crypto_mac.c
+++ b/library/psa_crypto_mac.c
@@ -236,6 +236,7 @@
     else
 #endif /* BUILTIN_ALG_HMAC */
     {
+        (void) operation;
         status = PSA_ERROR_NOT_SUPPORTED;
     }