--- /dev/null
+--- a/src/idn.c
++++ b/src/idn.c
+@@ -171,7 +171,7 @@ main (int argc, char *argv[])
+ (args_info.idna_to_unicode_given ? 1 : 0) +
+ (args_info.nfkc_given ? 1 : 0) != 1)
+ {
+- error (0, 0, _("only one of -s, -e, -d, -a, -u or -n can be specified"));
++ error (0, 0, "%s", _("only one of -s, -e, -d, -a, -u or -n can be specified"));
+ usage (EXIT_FAILURE);
+ }
+
+@@ -182,7 +182,7 @@ main (int argc, char *argv[])
+ fprintf (stderr, _("Charset `%s'.\n"), stringprep_locale_charset ());
+
+ if (!args_info.quiet_given && args_info.inputs_num == 0)
+- fprintf (stderr, _("Type each input string on a line by itself, "
++ fprintf (stderr, "%s", _("Type each input string on a line by itself, "
+ "terminated by a newline character.\n"));
+
+ do
+@@ -197,7 +197,7 @@ main (int argc, char *argv[])
+ if (feof (stdin))
+ break;
+
+- error (EXIT_FAILURE, errno, _("input error"));
++ error (EXIT_FAILURE, errno, "%s", _("input error"));
+ }
+
+ if (readbuf[strlen (readbuf) - 1] == '\n')
+@@ -214,7 +214,7 @@ main (int argc, char *argv[])
+ if (!q)
+ {
+ free (p);
+- error (EXIT_FAILURE, 0,
++ error (EXIT_FAILURE, 0, "%s",
+ _("could not convert from UTF-8 to UCS-4"));
+ }
+
+@@ -239,7 +239,7 @@ main (int argc, char *argv[])
+ if (!q)
+ {
+ free (r);
+- error (EXIT_FAILURE, 0,
++ error (EXIT_FAILURE, 0, "%s",
+ _("could not convert from UTF-8 to UCS-4"));
+ }
+
+@@ -275,7 +275,7 @@ main (int argc, char *argv[])
+ q = stringprep_utf8_to_ucs4 (p, -1, &len);
+ free (p);
+ if (!q)
+- error (EXIT_FAILURE, 0,
++ error (EXIT_FAILURE, 0, "%s",
+ _("could not convert from UTF-8 to UCS-4"));
+
+ if (args_info.debug_given)
+@@ -334,7 +334,7 @@ main (int argc, char *argv[])
+ r = stringprep_ucs4_to_utf8 (q, -1, NULL, NULL);
+ free (q);
+ if (!r)
+- error (EXIT_FAILURE, 0,
++ error (EXIT_FAILURE, 0, "%s",
+ _("could not convert from UCS-4 to UTF-8"));
+
+ p = stringprep_utf8_to_locale (r);
+@@ -358,7 +358,7 @@ main (int argc, char *argv[])
+ q = stringprep_utf8_to_ucs4 (p, -1, NULL);
+ free (p);
+ if (!q)
+- error (EXIT_FAILURE, 0,
++ error (EXIT_FAILURE, 0, "%s",
+ _("could not convert from UCS-4 to UTF-8"));
+
+ if (args_info.debug_given)
+@@ -436,7 +436,7 @@ main (int argc, char *argv[])
+ if (!q)
+ {
+ free (p);
+- error (EXIT_FAILURE, 0,
++ error (EXIT_FAILURE, 0, "%s",
+ _("could not convert from UCS-4 to UTF-8"));
+ }
+
+@@ -492,7 +492,7 @@ main (int argc, char *argv[])
+ r = stringprep_ucs4_to_utf8 (q, -1, NULL, NULL);
+ free (q);
+ if (!r)
+- error (EXIT_FAILURE, 0,
++ error (EXIT_FAILURE, 0, "%s",
+ _("could not convert from UTF-8 to UCS-4"));
+
+ p = stringprep_utf8_to_locale (r);
+@@ -521,7 +521,7 @@ main (int argc, char *argv[])
+ if (!q)
+ {
+ free (p);
+- error (EXIT_FAILURE, 0,
++ error (EXIT_FAILURE, 0, "%s",
+ _("could not convert from UTF-8 to UCS-4"));
+ }
+
+@@ -535,7 +535,7 @@ main (int argc, char *argv[])
+ r = stringprep_utf8_nfkc_normalize (p, -1);
+ free (p);
+ if (!r)
+- error (EXIT_FAILURE, 0, _("could not do NFKC normalization"));
++ error (EXIT_FAILURE, 0, "%s", _("could not do NFKC normalization"));
+
+ if (args_info.debug_given)
+ {
+@@ -545,7 +545,7 @@ main (int argc, char *argv[])
+ if (!q)
+ {
+ free (r);
+- error (EXIT_FAILURE, 0,
++ error (EXIT_FAILURE, 0, "%s",
+ _("could not convert from UTF-8 to UCS-4"));
+ }
+