-# else
- if (dfa->mb_cur_max > 1)
- for (i = 0; i < SBC_MAX; ++i)
- if (__btowc (i) == WEOF)
- re_set_fastmap (fastmap, icase, i);
-# endif /* not _LIBC */
+# endif /* _LIBC */
+
+ /* See if we have to start the match at all multibyte characters,
+ i.e. where we would not find an invalid sequence. This only
+ applies to multibyte character sets; for single byte character
+ sets, the SIMPLE_BRACKET again suffices. */
+ if (dfa->mb_cur_max > 1
+ && (cset->nchar_classes || cset->non_match
+# ifdef _LIBC
+ || cset->nequiv_classes
+# endif /* _LIBC */
+ ))
+ {
+ unsigned char c = 0;
+ do
+ {
+ mbstate_t mbs;
+ memset (&mbs, 0, sizeof (mbs));
+ if (__mbrtowc (NULL, (char *) &c, 1, &mbs) == (size_t) -2)
+ re_set_fastmap (fastmap, false, (int) c);
+ }
+ while (++c != 0);