--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,16 @@
 2010-03-19  Jim Meyering  <meyering@redhat.com>
 
+	regcomp.c: make non-_LIBC implementation of build_range_exp consistent
+	The _LIBC implementation of build_range_exp correctly honors the
+	RE_NO_EMPTY_RANGES flag when checking for reversed range endpoints.
+	However, the non-_LIBC implementation would ignore that syntax-bit
+	flag and return REG_ERANGE unconditionally.
+	This change makes it honor that flag.
+	* lib/regcomp.c (build_range_exp) [!_LIBC]: Add a parameter: "syntax".
+	Make two pointer parameters "const".
+	Use "syntax" bits in order to honor RE_NO_EMPTY_RANGES.
+	(parse_bracket_exp): Update caller.
+
 	regex.m4: correct the reversed range endpoint ([b-a]) test
 	* m4/regex.m4: When requiring that [b-a] evoke failure,
 	use RE_NO_EMPTY_RANGES.  This makes this entire configure-time

--- a/lib/regcomp.c
+++ b/lib/regcomp.c
@@ -2622,11 +2622,17 @@
 static reg_errcode_t
 internal_function
 # ifdef RE_ENABLE_I18N
-build_range_exp (bitset_t sbcset, re_charset_t *mbcset, Idx *range_alloc,
-		 bracket_elem_t *start_elem, bracket_elem_t *end_elem)
+build_range_exp (const reg_syntax_t syntax,
+                 bitset_t sbcset,
+                 re_charset_t *mbcset,
+                 Idx *range_alloc,
+                 const bracket_elem_t *start_elem,
+                 const bracket_elem_t *end_elem)
 # else /* not RE_ENABLE_I18N */
-build_range_exp (bitset_t sbcset, bracket_elem_t *start_elem,
-		 bracket_elem_t *end_elem)
+build_range_exp (const reg_syntax_t syntax,
+                 bitset_t sbcset,
+                 const bracket_elem_t *start_elem,
+                 const bracket_elem_t *end_elem)
 # endif /* not RE_ENABLE_I18N */
 {
   unsigned int start_ch, end_ch;
@@ -2665,7 +2671,9 @@
       return REG_ECOLLATE;
     cmp_buf[0] = start_wc;
     cmp_buf[4] = end_wc;
-    if (wcscoll (cmp_buf, cmp_buf + 4) > 0)
+
+    if (BE ((syntax & RE_NO_EMPTY_RANGES)
+            && wcscoll (cmp_buf, cmp_buf + 4) > 0, 0))
       return REG_ERANGE;
 
     /* Got valid collation sequence values, add them as a new entry.
@@ -3168,11 +3176,11 @@
 				  &start_elem, &end_elem);
 #else
 # ifdef RE_ENABLE_I18N
-	  *err = build_range_exp (sbcset,
+	  *err = build_range_exp (syntax, sbcset,
 				  dfa->mb_cur_max > 1 ? mbcset : NULL,
 				  &range_alloc, &start_elem, &end_elem);
 # else
-	  *err = build_range_exp (sbcset, &start_elem, &end_elem);
+	  *err = build_range_exp (syntax, sbcset, &start_elem, &end_elem);
 # endif
 #endif /* RE_ENABLE_I18N */
 	  if (BE (*err != REG_NOERROR, 0))