diff --git a/library/ssl_debug_helpers.h b/library/ssl_debug_helpers.h
index 2ffc5f4..29b64dc 100644
--- a/library/ssl_debug_helpers.h
+++ b/library/ssl_debug_helpers.h
@@ -39,7 +39,7 @@
 
 const char *mbedtls_ssl_key_export_type_str( mbedtls_ssl_key_export_type in );
 
-
+const char *mbedtls_ssl_sig_alg_to_str( uint16_t in );
 
 #endif /* MBEDTLS_DEBUG_C */