diff --git a/src/dd.c b/src/dd.c
index 9dc824422..276ed7472 100644
--- a/src/dd.c
+++ b/src/dd.c
@@ -977,15 +977,13 @@ apply_translations (void)
   if (conversions_mask & C_UCASE)
     {
       for (i = 0; i < 256; i++)
-	if (ISLOWER (trans_table[i]))
-	  trans_table[i] = TOUPPER (trans_table[i]);
+	trans_table[i] = toupper (trans_table[i]);
       translation_needed = true;
     }
   else if (conversions_mask & C_LCASE)
     {
       for (i = 0; i < 256; i++)
-	if (ISUPPER (trans_table[i]))
-	  trans_table[i] = TOLOWER (trans_table[i]);
+	trans_table[i] = tolower (trans_table[i]);
       translation_needed = true;
     }