diff --git a/library/bignum.c b/library/bignum.c
index d28d3be..eb32640 100644
--- a/library/bignum.c
+++ b/library/bignum.c
@@ -838,6 +838,11 @@
 
 cleanup:
 
+    /*
+     * This function is also used to import keys. However, wiping the buffers
+     * upon failure is not necessary because failure only can happen before any
+     * input is copied.
+     */
     return( ret );
 }
 
@@ -875,6 +880,11 @@
 
 cleanup:
 
+    /*
+     * This function is also used to import keys. However, wiping the buffers
+     * upon failure is not necessary because failure only can happen before any
+     * input is copied.
+     */
     return( ret );
 }