[newlib-cygwin/main] Cygwin: regex: fix faulty check for valid range expression

[Corinna Vinschen]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=59241913330c15d25ea569f1309af1c746dc07fa

commit 59241913330c15d25ea569f1309af1c746dc07fa
Author:     Corinna Vinschen <corinna@vinschen.de>
AuthorDate: Thu Mar 16 21:09:53 2023 +0100
Commit:     Corinna Vinschen <corinna@vinschen.de>
CommitDate: Mon Mar 20 12:58:03 2023 +0100

    Cygwin: regex: fix faulty check for valid range expression
    
    Except for the "C" or "POSIX" locale, checking for start <= finish
    is always wrong.  Range start must be <= range finish in terms of the
    locale's collating order.  So make sure to call always wcscoll(), even
    in the "C"/"POSIX" locale, which makes wcscoll equivalent to wcscmp
    anyway.
    
    Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

Diff:
---
 winsup/cygwin/regex/regcomp.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/winsup/cygwin/regex/regcomp.c b/winsup/cygwin/regex/regcomp.c
index 418e24a90ad2..7899ae7fce3c 100644
--- a/winsup/cygwin/regex/regcomp.c
+++ b/winsup/cygwin/regex/regcomp.c
@@ -1145,7 +1145,7 @@ p_b_term(struct parse *p, cset *cs)
 #else
 			if (MB_CUR_MAX > 1) {
 #endif
-				(void)REQUIRE(start <= finish, REG_ERANGE);
+				(void)REQUIRE(p_range_cmp(start, finish) <= 0, REG_ERANGE);
 				CHaddrange(p, cs, start, finish);
 			} else {
 				(void)REQUIRE(p_range_cmp(start, finish) <= 0, REG_ERANGE);
@@ -1665,8 +1665,6 @@ CHaddrange(struct parse *p, cset *cs, wint_t min, wint_t max)
 
 	for (; min < NC && min <= max; min++)
 		CHadd(p, cs, min);
-	if (min >= max)
-		return;
 	newranges = reallocarray(cs->ranges, cs->nranges + 1,
 	    sizeof(*cs->ranges));
 	if (newranges == NULL) {