diff --git a/src/core/wee-utf8.c b/src/core/wee-utf8.c
index 950c603..b0d58a0 100644
--- a/src/core/wee-utf8.c
+++ b/src/core/wee-utf8.c
@@ -501,11 +501,11 @@ utf8_charcasecmp_range (const char *string1, const char *string2, int range)
         return (string1) ? 1 : ((string2) ? -1 : 0);
 
     wchar1 = utf8_wide_char (string1);
-    if ((wchar1 >= 'A') && (wchar1 < 'A' + (unsigned int)range))
+    if ((wchar1 >= (wint_t)'A') && (wchar1 < (wint_t)('A' + range)))
         wchar1 += ('a' - 'A');
 
     wchar2 = utf8_wide_char (string2);
-    if ((wchar2 >= 'A') && (wchar2 < 'A' + (unsigned int)range))
+    if ((wchar2 >= (wint_t)'A') && (wchar2 < (wint_t)('A' + range)))
         wchar2 += ('a' - 'A');
 
     return (wchar1 < wchar2) ? -1 : ((wchar1 == wchar2) ? 0 : 1);