Index: uspace/lib/libc/include/ctype.h
===================================================================
--- uspace/lib/libc/include/ctype.h	(revision a5da44692fdd60126ee6a59330558b0460f54775)
+++ uspace/lib/libc/include/ctype.h	(revision b9e7944055fbefcc560af681ef9fafaffaeaba03)
@@ -80,5 +80,5 @@
 {
 	if (isupper(c))
-		return (c + ('a' - 'A' > 0 ? 'a' - 'A' : 'A' - 'a'));
+		return (c + ('a' - 'A'));
 	else
 		return c;
@@ -88,5 +88,5 @@
 {
 	if (islower(c))
-		return (c - ('a' - 'A' > 0 ? 'a' - 'A' : 'A' - 'a'));
+		return (c + ('A' - 'a'));
 	else
 		return c;