diff --git a/include/psa/crypto_struct.h b/include/psa/crypto_struct.h
index 94242f8..f08fdc8 100644
--- a/include/psa/crypto_struct.h
+++ b/include/psa/crypto_struct.h
@@ -175,9 +175,6 @@
 {
     uint8_t *info;
     size_t info_length;
-    psa_mac_operation_t hmac;
-    uint8_t prk[PSA_HASH_MAX_SIZE];
-    uint8_t output_block[PSA_HASH_MAX_SIZE];
 #if PSA_HASH_MAX_SIZE > 0xff
 #error "PSA_HASH_MAX_SIZE does not fit in uint8_t"
 #endif
@@ -185,6 +182,9 @@
     uint8_t block_number;
     unsigned int state : 2;
     unsigned int info_set : 1;
+    uint8_t output_block[PSA_HASH_MAX_SIZE];
+    uint8_t prk[PSA_HASH_MAX_SIZE];
+    psa_mac_operation_t hmac;
 } psa_hkdf_key_derivation_t;
 #endif /* MBEDTLS_PSA_BUILTIN_ALG_HKDF */
 
diff --git a/library/psa_crypto_aead.c b/library/psa_crypto_aead.c
index 356679c..2769028 100644
--- a/library/psa_crypto_aead.c
+++ b/library/psa_crypto_aead.c
@@ -32,6 +32,8 @@
 
 typedef struct
 {
+    psa_algorithm_t core_alg;
+    uint8_t tag_length;
     union
     {
         unsigned dummy; /* Make the union non-empty even with no supported algorithms. */
@@ -45,11 +47,9 @@
         mbedtls_chachapoly_context chachapoly;
 #endif /* MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305 */
     } ctx;
-    psa_algorithm_t core_alg;
-    uint8_t tag_length;
 } aead_operation_t;
 
-#define AEAD_OPERATION_INIT {{0}, 0, 0}
+#define AEAD_OPERATION_INIT {0, 0, {0}}
 
 static void psa_aead_abort_internal( aead_operation_t *operation )
 {