diff --git a/programs/ssl/ssl_client2.c b/programs/ssl/ssl_client2.c
index 54cdd7d..16bd619 100644
--- a/programs/ssl/ssl_client2.c
+++ b/programs/ssl/ssl_client2.c
@@ -1207,7 +1207,7 @@
     const char *pers = "ssl_client2";
 
 #if defined(MBEDTLS_USE_PSA_CRYPTO)
-    psa_key_handle_t slot = 0;
+    psa_key_handle_t slot = PSA_KEY_HANDLE_INIT;
     psa_algorithm_t alg = 0;
     psa_key_attributes_t key_attributes;
     psa_status_t status;
@@ -1232,7 +1232,7 @@
     mbedtls_x509_crt clicert;
     mbedtls_pk_context pkey;
 #if defined(MBEDTLS_USE_PSA_CRYPTO)
-    psa_key_handle_t key_slot = 0; /* invalid key slot */
+    psa_key_handle_t key_slot = PSA_KEY_HANDLE_INIT; /* invalid key slot */
 #endif
 #endif
     char *p, *q;