diff --git a/library/x509_crt.c b/library/x509_crt.c
index 5f2af7fcb..0676e6481 100644
--- a/library/x509_crt.c
+++ b/library/x509_crt.c
@@ -3263,7 +3263,7 @@ static unsigned x509_crt_verify_chain_len(
     return( chain->len );
 }
 
-#else
+#else /* !MBEDTLS_X509_REMOVE_VERIFY_CALLBACK */
 
 /*
  * Reset (init or clear) a verify_chain