--- libdatrie-0.2.14/tools/trietool.c.orig	2025-05-15 11:25:23.000000000 +0200
+++ libdatrie-0.2.14/tools/trietool.c	2025-12-22 01:49:37.149348030 +0100
@@ -121,7 +121,7 @@
     assert (sizeof (AlphaChar) == 4);
 
     /* convert to UCS-4LE */
-    res = iconv (env->to_alpha_conv, (char **) &in_p, &in_left,
+    res = iconv (env->to_alpha_conv, (const char **) &in_p, &in_left,
                  &out_p, &out_left);
 
     if (res == (size_t) -1)
@@ -166,7 +166,7 @@
     }
 
     /* convert UCS-4LE to locale codeset */
-    res = iconv (env->from_alpha_conv, (char **) &in, &in_left,
+    res = iconv (env->from_alpha_conv, (const char **) &in, &in_left,
                  &out, &out_size);
     *out = 0;