fix the [...] bug also for relatively unusual uni-byte encodings

* src/dfa.c (setbit_case_fold): Also handle uni-byte locales
like the one mentioned in the original report: see 2011-05-07
commit d98338eb.  Re-reported by Santiago Ruano Rincón.
Note that most uni-byte locales are not affected.
* NEWS (Bug fixes): Mention it.

1 files changed, 7 insertions, 3 deletions

diff --git a/src/dfa.c b/src/dfa.c
index b41cbb6b..83386aae 100644
--- a/src/dfa.c
+++ b/src/dfa.c
@@ -573,10 +573,14 @@ setbit_case_fold (
   else
     {
 #if MBS_SUPPORT
-      int b2 = wctob ((unsigned char) b);
-      if (b2 == EOF || b2 == b)
+      /* Below, note how when b2 != b and we have a uni-byte locale
+         (MB_CUR_MAX == 1), we set b = b2.  I.e., in a uni-byte locale,
+         we can safely call setbit with a non-EOF value returned by wctob.  */
+      int b2 = wctob (b);
+      if (b2 == EOF || b2 == b || (MB_CUR_MAX == 1 ? (b=b2), 1 : 0))
 #endif
-        setbit (b, c);
+        if (b < NOTCHAR)
+          setbit (b, c);
     }
 }