diff --git a/include/psa/crypto_builtin_composites.h b/include/psa/crypto_builtin_composites.h
index e1acf39..3b0f82a 100644
--- a/include/psa/crypto_builtin_composites.h
+++ b/include/psa/crypto_builtin_composites.h
@@ -63,12 +63,9 @@
 {
     psa_algorithm_t alg;
     unsigned int key_set : 1;
-    unsigned int iv_required : 1;
-    unsigned int iv_set : 1;
     unsigned int has_input : 1;
     unsigned int is_sign : 1;
     uint8_t mac_size;
-    unsigned int id;
     union
     {
         unsigned dummy; /* Make the union non-empty even with no supported algorithms. */
@@ -81,7 +78,7 @@
     } ctx;
 } mbedtls_psa_mac_operation_t;
 
-#define MBEDTLS_PSA_MAC_OPERATION_INIT {0, 0, 0, 0, 0, 0, 0, 0, {0}}
+#define MBEDTLS_PSA_MAC_OPERATION_INIT {0, 0, 0, 0, 0, {0}}
 
 /*
  * BEYOND THIS POINT, TEST DRIVER DECLARATIONS ONLY.
diff --git a/library/psa_crypto_mac.c b/library/psa_crypto_mac.c
index 5ea2f17..0189cde 100644
--- a/library/psa_crypto_mac.c
+++ b/library/psa_crypto_mac.c
@@ -247,15 +247,12 @@
 
     operation->alg = PSA_ALG_FULL_LENGTH_MAC( alg );
     operation->key_set = 0;
-    operation->iv_set = 0;
-    operation->iv_required = 0;
     operation->has_input = 0;
     operation->is_sign = 0;
 
 #if defined(BUILTIN_ALG_CMAC)
     if( operation->alg == PSA_ALG_CMAC )
     {
-        operation->iv_required = 0;
         mbedtls_cipher_init( &operation->ctx.cmac );
         status = PSA_SUCCESS;
     }
@@ -312,8 +309,6 @@
 
     operation->alg = 0;
     operation->key_set = 0;
-    operation->iv_set = 0;
-    operation->iv_required = 0;
     operation->has_input = 0;
     operation->is_sign = 0;
 
@@ -452,8 +447,6 @@
 {
     if( ! operation->key_set )
         return( PSA_ERROR_BAD_STATE );
-    if( operation->iv_required && ! operation->iv_set )
-        return( PSA_ERROR_BAD_STATE );
     operation->has_input = 1;
 
 #if defined(BUILTIN_ALG_CMAC)
@@ -486,8 +479,6 @@
 {
     if( ! operation->key_set )
         return( PSA_ERROR_BAD_STATE );
-    if( operation->iv_required && ! operation->iv_set )
-        return( PSA_ERROR_BAD_STATE );
 
     if( mac_size < operation->mac_size )
         return( PSA_ERROR_BUFFER_TOO_SMALL );