diff --git a/src/fcstr.c b/src/fcstr.c
index 3a31b22..533e91d 100644
--- a/src/fcstr.c
+++ b/src/fcstr.c
@@ -72,12 +72,15 @@ FcStrCmpIgnoreCase (const FcChar8 *s1, const FcChar8 *s2)
     {
 	c1 = *s1++;
 	c2 = *s2++;
-	if (!c1 || !c2)
+	if (!c1)
 	    break;
-	c1 = FcToLower (c1);
-	c2 = FcToLower (c2);
 	if (c1 != c2)
-	    break;
+	{
+	    c1 = FcToLower (c1);
+	    c2 = FcToLower (c2);
+	    if (c1 != c2)
+		break;
+	}
     }
     return (int) c1 - (int) c2;
 }