+#if defined HAVE_STRERROR_R || _LIBC
+ char errbuf[1024];
+# if STRERROR_R_CHAR_P || _LIBC
+ s = __strerror_r (errnum, errbuf, sizeof errbuf);
+# else
+ if (__strerror_r (errnum, errbuf, sizeof errbuf) == 0)
+ s = errbuf;
+ else
+ s = 0;
+# endif
+#else
+ s = strerror (errnum);
+#endif
+
+#if !_LIBC
+ if (! s)
+ s = _("Unknown system error");
+#endif
+
+#if _LIBC
+ __fxprintf (NULL, ": %s", s);
+#else
+ fprintf (stderr, ": %s", s);
+#endif
+}
+
+static void _GL_ATTRIBUTE_FORMAT_PRINTF (3, 0) _GL_ARG_NONNULL ((3))
+error_tail (int status, int errnum, const char *message, va_list args)
+{
+#if _LIBC
+ if (_IO_fwide (stderr, 0) > 0)
+ {
+# define ALLOCA_LIMIT 2000
+ size_t len = strlen (message) + 1;
+ wchar_t *wmessage = NULL;
+ mbstate_t st;
+ size_t res;
+ const char *tmp;
+ bool use_malloc = false;
+
+ while (1)
+ {
+ if (__libc_use_alloca (len * sizeof (wchar_t)))
+ wmessage = (wchar_t *) alloca (len * sizeof (wchar_t));
+ else
+ {
+ if (!use_malloc)
+ wmessage = NULL;
+
+ wchar_t *p = (wchar_t *) realloc (wmessage,
+ len * sizeof (wchar_t));
+ if (p == NULL)
+ {
+ free (wmessage);
+ fputws_unlocked (L"out of memory\n", stderr);
+ return;
+ }
+ wmessage = p;
+ use_malloc = true;
+ }
+
+ memset (&st, '\0', sizeof (st));
+ tmp = message;
+
+ res = mbsrtowcs (wmessage, &tmp, len, &st);
+ if (res != len)
+ break;
+
+ if (__builtin_expect (len >= SIZE_MAX / 2, 0))
+ {
+ /* This really should not happen if everything is fine. */
+ res = (size_t) -1;
+ break;
+ }
+
+ len *= 2;
+ }
+
+ if (res == (size_t) -1)
+ {
+ /* The string cannot be converted. */
+ if (use_malloc)
+ {
+ free (wmessage);
+ use_malloc = false;
+ }
+ wmessage = (wchar_t *) L"???";
+ }
+
+ __vfwprintf (stderr, wmessage, args);
+
+ if (use_malloc)
+ free (wmessage);
+ }
+ else
+#endif
+ vfprintf (stderr, message, args);
+ va_end (args);
+
+ ++error_message_count;
+ if (errnum)
+ print_errno_message (errnum);
+#if _LIBC
+ __fxprintf (NULL, "\n");
+#else
+ putc ('\n', stderr);
+#endif
+ fflush (stderr);
+ if (status)
+ exit (status);