diff --git a/src/chars.c b/src/chars.c
index a42f53dd..3f6421a5 100644
--- a/src/chars.c
+++ b/src/chars.c
@@ -857,7 +857,7 @@ bool is_valid_mbstring(const char *s)
 
     return 
 #ifdef NANO_WIDE
-	(!ISSET(NO_UTF8)) ?
+	!ISSET(NO_UTF8) ?
 	(mbstowcs(NULL, s, (size_t)-1) != (size_t)-1) :
 #endif