Add generic C.UTF-8 locale (Bug 17318)

We add a new C.UTF-8 locale. This locale is not builtin to glibc, but
is provided as a distinct locale. The locale provides full support for
UTF-8 and this includes full code point sorting via STRCMP-based
collation (strcmp or wcscmp).

The collation uses a new keyword 'codepoint_collation' which drops all
collation rules and generates an empty zero rules collation to enable
STRCMP usage in collation. This ensures that we get full code point
sorting for C.UTF-8 with a minimal 1406 bytes of overhead (LC_COLLATE
structure information and ASCII collating tables).

The new locale is added to SUPPORTED. Minimal test data for specific
code points (minus those not supported by collate-test) is provided in
C.UTF-8.in, and this verifies code point sorting is working reasonably
across the range. The locale was tested manually with the full set of
code points without failure.

The locale is harmonized with locales already shipping in various
downstream distributions. A new tst-iconv9 test is added which verifies
the C.UTF-8 locale is generally usable.

Testing for fnmatch, regexec, and recomp is provided by extending
bug-regex1, bugregex19, bug-regex4, bug-regex6, transbug, tst-fnmatch,
tst-regcomp-truncated, and tst-regex to use C.UTF-8.

Tested on x86_64 or i686 without regression.

Reviewed-by: Florian Weimer <fweimer@redhat.com>

16 files changed, 1131 insertions, 34 deletions

diff --git a/NEWS b/NEWS
index 79c895e..5b014fa 100644
--- a/NEWS
+++ b/NEWS
@@ -9,7 +9,15 @@ Version 2.35
 
 Major new features:
 
-  [Add new features here]
+* Support for the C.UTF-8 locale has been added to glibc.  The locale
+  supports full code-point sorting for all valid Unicode code points.  A
+  limitation in the framework for fnmatch, regexec, and regcomp requires
+  a compromise to save space and only ASCII-based range expressions are
+  supported for now (see bug 28255).  The full size of the locale is
+  only ~400KiB, with 346KiB coming from LC_CTYPE information for
+  Unicode.  This locale harmonizes downstream C.UTF-8 already shipping
+  in various downstream distributions.  The locale is not built into
+  glibc, and must be installed.
 
 Deprecated and removed features, and other changes affecting compatibility:
 
diff --git a/iconv/Makefile b/iconv/Makefile
index 07d77c9..9993f2d 100644
--- a/iconv/Makefile
+++ b/iconv/Makefile
@@ -43,8 +43,19 @@ CFLAGS-charmap.c += -DCHARMAP_PATH='"$(i18ndir)/charmaps"' \
 CFLAGS-linereader.c += -DNO_TRANSLITERATION
 CFLAGS-simple-hash.c += -I../locale
 
-tests	= tst-iconv1 tst-iconv2 tst-iconv3 tst-iconv4 tst-iconv5 tst-iconv6 \
-	  tst-iconv7 tst-iconv8 tst-iconv-mt tst-iconv-opt
+tests = \
+	tst-iconv1 \
+	tst-iconv2 \
+	tst-iconv3 \
+	tst-iconv4 \
+	tst-iconv5 \
+	tst-iconv6 \
+	tst-iconv7 \
+	tst-iconv8 \
+	tst-iconv9 \
+	tst-iconv-mt \
+	tst-iconv-opt \
+	# tests
 
 others		= iconv_prog iconvconfig
 install-others-programs	= $(inst_bindir)/iconv
@@ -83,10 +94,15 @@ endif
 include ../Rules
 
 ifeq ($(run-built-tests),yes)
-LOCALES := en_US.UTF-8
+# We have to generate locales (list sorted alphabetically)
+LOCALES := \
+	C.UTF-8 \
+	en_US.UTF-8 \
+	# LOCALES
 include ../gen-locales.mk
 
 $(objpfx)tst-iconv-opt.out: $(gen-locales)
+$(objpfx)tst-iconv9.out: $(gen-locales)
 endif
 
 $(inst_bindir)/iconv: $(objpfx)iconv_prog $(+force)
diff --git a/iconv/tst-iconv9.c b/iconv/tst-iconv9.c
new file mode 100644
index 0000000..c46b183
--- /dev/null
+++ b/iconv/tst-iconv9.c
@@ -0,0 +1,87 @@
+/* Verify that using C.UTF-8 works.
+
+   Copyright (C) 2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <iconv.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <string.h>
+#include <support/support.h>
+#include <support/check.h>
+
+/* This test does two things:
+   (1) Verify that we have likely included translit_combining in C.UTF-8.
+   (2) Verify default_missing is '?' as expected.  */
+
+/* ISO-8859-1 encoding of "für".  */
+char iso88591_in[] = { 0x66, 0xfc, 0x72, 0x0 };
+/* ASCII transliteration is "fur" with C.UTF-8 translit_combining.  */
+char ascii_exp[] = { 0x66, 0x75, 0x72, 0x0 };
+
+/* First 3-byte UTF-8 code point.  */
+char utf8_in[] = { 0xe0, 0xa0, 0x80, 0x0 };
+/* There is no ASCII transliteration for SAMARITAN LETTER ALAF
+   so we get default_missing used which is '?'.  */
+char default_missing_exp[] = { 0x3f, 0x0 };
+
+static int
+do_test (void)
+{
+  char ascii_out[5];
+  iconv_t cd;
+  char *inbuf;
+  char *outbuf;
+  size_t inbytes;
+  size_t outbytes;
+  size_t n;
+
+  /* The C.UTF-8 locale should include translit_combining, which provides
+     the transliteration for "LATIN SMALL LETTER U WITH DIAERESIS" which
+     is not provided by locale/C-translit.h.in.  */
+  xsetlocale (LC_ALL, "C.UTF-8");
+
+  /* From ISO-8859-1 to ASCII.  */
+  cd = iconv_open ("ASCII//TRANSLIT,IGNORE", "ISO-8859-1");
+  TEST_VERIFY (cd != (iconv_t) -1);
+  inbuf = iso88591_in;
+  inbytes = 3;
+  outbuf = ascii_out;
+  outbytes = 3;
+  n = iconv (cd, &inbuf, &inbytes, &outbuf, &outbytes);
+  TEST_VERIFY (n != -1);
+  *outbuf = '\0';
+  TEST_COMPARE_BLOB (ascii_out, 3, ascii_exp, 3);
+  TEST_VERIFY (iconv_close (cd) == 0);
+
+  /* From UTF-8 to ASCII.  */
+  cd = iconv_open ("ASCII//TRANSLIT,IGNORE", "UTF-8");
+  TEST_VERIFY (cd != (iconv_t) -1);
+  inbuf = utf8_in;
+  inbytes = 3;
+  outbuf = ascii_out;
+  outbytes = 3;
+  n = iconv (cd, &inbuf, &inbytes, &outbuf, &outbytes);
+  TEST_VERIFY (n != -1);
+  *outbuf = '\0';
+  TEST_COMPARE_BLOB (ascii_out, 1, default_missing_exp, 1);
+  TEST_VERIFY (iconv_close (cd) == 0);
+
+  return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/localedata/C.UTF-8.in b/localedata/C.UTF-8.in
new file mode 100644
index 0000000..c31dcc2
--- /dev/null
+++ b/localedata/C.UTF-8.in
@@ -0,0 +1,157 @@
+
 ; <U1>
+ ; <U2>
+ ; <U3>
+ ; <U4>
+ ; <U5>
+ ; <U6>
+ ; <U7>
+ ; <U8>
+ ; <UE>
+ ; <UF>
+ ; <U10>
+ ; <U11>
+ ; <U12>
+ ; <U13>
+ ; <U14>
+ ; <U15>
+ ; <U16>
+ ; <U17>
+ ; <U18>
+ ; <U19>
+ ; <U1A>
+ ; <U1B>
+ ; <U1C>
+ ; <U1D>
+ ; <U1E>
+ ; <U1F>
+! ; <U21>
+" ; <U22>
+# ; <U23>
+$ ; <U24>
+% ; <U25>
+& ; <U26>
+' ; <U27>
+) ; <U29>
+* ; <U2A>
++ ; <U2B>
+, ; <U2C>
+- ; <U2D>
+. ; <U2E>
+/ ; <U2F>
+0 ; <U30>
+1 ; <U31>
+2 ; <U32>
+3 ; <U33>
+4 ; <U34>
+5 ; <U35>
+6 ; <U36>
+7 ; <U37>
+8 ; <U38>
+9 ; <U39>
+< ; <U3C>
+= ; <U3D>
+> ; <U3E>
+? ; <U3F>
+@ ; <U40>
+A ; <U41>
+B ; <U42>
+C ; <U43>
+D ; <U44>
+E ; <U45>
+F ; <U46>
+G ; <U47>
+H ; <U48>
+I ; <U49>
+J ; <U4A>
+K ; <U4B>
+L ; <U4C>
+M ; <U4D>
+N ; <U4E>
+O ; <U4F>
+P ; <U50>
+Q ; <U51>
+R ; <U52>
+S ; <U53>
+T ; <U54>
+U ; <U55>
+V ; <U56>
+W ; <U57>
+X ; <U58>
+Y ; <U59>
+Z ; <U5A>
+[ ; <U5B>
+\ ; <U5C>
+] ; <U5D>
+^ ; <U5E>
+_ ; <U5F>
+` ; <U60>
+a ; <U61>
+b ; <U62>
+c ; <U63>
+d ; <U64>
+e ; <U65>
+f ; <U66>
+g ; <U67>
+h ; <U68>
+i ; <U69>
+j ; <U6A>
+k ; <U6B>
+l ; <U6C>
+m ; <U6D>
+n ; <U6E>
+o ; <U6F>
+p ; <U70>
+q ; <U71>
+r ; <U72>
+s ; <U73>
+t ; <U74>
+u ; <U75>
+v ; <U76>
+w ; <U77>
+x ; <U78>
+y ; <U79>
+z ; <U7A>
+{ ; <U7B>
+| ; <U7C>
+} ; <U7D>
+~ ; <U7E>
+ ; <U7F>
+€ ; <U80>
+ÿ ; <UFF>
+Ā ; <U100>
+࿿ ; <UFFF>
+က ; <U1000>
+� ; <UFFFD>
+￿ ; <UFFFF>
+𐀀 ; <U10000>
+🿿 ; <U1FFFF>
+𠀀 ; <U20000>
+𯿿 ; <U2FFFF>
+𰀀 ; <U30000>
+𿿾 ; <U3FFFE>
+񀀀 ; <U40000>
+񏿿 ; <U4FFFF>
+񐀀 ; <U50000>
+񟿿 ; <U5FFFF>
+񠀀 ; <U60000>
+񯿿 ; <U6FFFF>
+񰀀 ; <U70000>
+񿿿 ; <U7FFFF>
+򀀀 ; <U80000>
+򏿿 ; <U8FFFF>
+򐀀 ; <U90000>
+򟿿 ; <U9FFFF>
+򠀀 ; <UA0000>
+򯿿 ; <UAFFFF>
+򰀀 ; <UB0000>
+򿿿 ; <UBFFFF>
+󀀁 ; <UC0001>
+󏿌 ; <UCFFCC>
+󐀎 ; <UD000E>
+󟿿 ; <UDFFFF>
+󠀁 ; <UE0001>
+󯿿 ; <UEFFFF>
+󰀁 ; <UF0001>
+󿿿 ; <UFFFFF>
+􀀁 ; <U100001>
+􏿿 ; <U10FFFF>
diff --git a/localedata/Makefile b/localedata/Makefile
index f585e0d..66a2696 100644
--- a/localedata/Makefile
+++ b/localedata/Makefile
@@ -47,6 +47,7 @@ test-input := \
 	bg_BG.UTF-8 \
 	br_FR.UTF-8 \
 	bs_BA.UTF-8 \
+	C.UTF-8 \
 	ckb_IQ.UTF-8 \
 	cmn_TW.UTF-8 \
 	crh_UA.UTF-8 \
@@ -206,6 +207,7 @@ LOCALES := \
 	bg_BG.UTF-8 \
 	br_FR.UTF-8 \
 	bs_BA.UTF-8 \
+	C.UTF-8 \
 	ckb_IQ.UTF-8 \
 	cmn_TW.UTF-8 \
 	crh_UA.UTF-8 \
diff --git a/localedata/SUPPORTED b/localedata/SUPPORTED
index 1ee5b5e..d768aa4 100644
--- a/localedata/SUPPORTED
+++ b/localedata/SUPPORTED
@@ -79,6 +79,7 @@ brx_IN/UTF-8 \
 bs_BA.UTF-8/UTF-8 \
 bs_BA/ISO-8859-2 \
 byn_ER/UTF-8 \
+C.UTF-8/UTF-8 \
 ca_AD.UTF-8/UTF-8 \
 ca_AD/ISO-8859-15 \
 ca_ES.UTF-8/UTF-8 \
diff --git a/localedata/locales/C b/localedata/locales/C
new file mode 100644
index 0000000..ca801c7
--- /dev/null
+++ b/localedata/locales/C
@@ -0,0 +1,194 @@
+escape_char /
+comment_char %
+% Locale for C locale in UTF-8
+
+LC_IDENTIFICATION
+title      "C locale"
+source     ""
+address    ""
+contact    ""
+email      "bug-glibc-locales@gnu.org"
+tel        ""
+fax        ""
+language   ""
+territory  ""
+revision   "2.0"
+date       "2020-06-28"
+category  "i18n:2012";LC_IDENTIFICATION
+category  "i18n:2012";LC_CTYPE
+category  "i18n:2012";LC_COLLATE
+category  "i18n:2012";LC_TIME
+category  "i18n:2012";LC_NUMERIC
+category  "i18n:2012";LC_MONETARY
+category  "i18n:2012";LC_MESSAGES
+category  "i18n:2012";LC_PAPER
+category  "i18n:2012";LC_NAME
+category  "i18n:2012";LC_ADDRESS
+category  "i18n:2012";LC_TELEPHONE
+category  "i18n:2012";LC_MEASUREMENT
+END LC_IDENTIFICATION
+
+LC_CTYPE
+% Include only the i18n character type classes without any of the
+% transliteration that i18n uses by default.
+copy "i18n_ctype"
+
+% Include the neutral transliterations.  The builtin C and
+% POSIX locales have +1600 transliterations that are built into
+% the locales, and these are a superset of those.
+translit_start
+include "translit_neutral";""
+% We must use '?' for default_missing because the transliteration
+% framework includes it directly into the output and so it must
+% be compatible with ASCII if that is the target character set.
+default_missing <U003F>
+translit_end
+
+% Include the transliterations that can convert combined characters.
+% These are generally expected by users.
+translit_start
+include "translit_combining";""
+translit_end
+
+END LC_CTYPE
+
+LC_COLLATE
+% The keyword 'codepoint_collation' in any part of any LC_COLLATE
+% immediately discards all collation information and causes the
+% locale to use strcmp/wcscmp for collation comparison.  This is
+% exactly what is needed for C (ASCII) or C.UTF-8.
+codepoint_collation
+END LC_COLLATE
+
+LC_MONETARY
+
+% This is the 14652 i18n fdcc-set definition for the LC_MONETARY
+% category (except for the int_curr_symbol and currency_symbol, they are
+% empty in the 14652 i18n fdcc-set definition and also empty in
+% glibc/locale/C-monetary.c.).
+int_curr_symbol     ""
+currency_symbol     ""
+mon_decimal_point   "."
+mon_thousands_sep   ""
+mon_grouping        -1
+positive_sign       ""
+negative_sign       "-"
+int_frac_digits     -1
+frac_digits         -1
+p_cs_precedes       -1
+int_p_sep_by_space  -1
+p_sep_by_space      -1
+n_cs_precedes       -1
+int_n_sep_by_space  -1
+n_sep_by_space      -1
+p_sign_posn         -1
+n_sign_posn         -1
+%
+END LC_MONETARY
+
+LC_NUMERIC
+% This is the POSIX Locale definition for
+% the LC_NUMERIC category.
+%
+decimal_point   "."
+thousands_sep   ""
+grouping        -1
+END LC_NUMERIC
+
+LC_TIME
+% This is the POSIX Locale definition for the LC_TIME category with the
+% exception that time is per ISO 8601 and 24-hour.
+%
+% Abbreviated weekday names (%a)
+abday       "Sun";"Mon";"Tue";"Wed";"Thu";"Fri";"Sat"
+
+% Full weekday names (%A)
+day         "Sunday";"Monday";"Tuesday";"Wednesday";"Thursday";/
+            "Friday";"Saturday"
+
+% Abbreviated month names (%b)
+abmon       "Jan";"Feb";"Mar";"Apr";"May";"Jun";"Jul";"Aug";"Sep";/
+            "Oct";"Nov";"Dec"
+
+% Full month names (%B)
+mon         "January";"February";"March";"April";"May";"June";"July";/
+            "August";"September";"October";"November";"December"
+
+% Week description, consists of three fields:
+% 1. Number of days in a week.
+% 2. Gregorian date that is a first weekday (19971130 for Sunday, 19971201 for Monday).
+% 3. The weekday number to be contained in the first week of the year.
+%
+% ISO 8601 conforming applications should use the values 7, 19971201 (a
+% Monday), and 4 (Thursday), respectively.
+week    7;19971201;4
+first_weekday	1
+first_workday	2
+
+% Appropriate date and time representation (%c)
+d_t_fmt "%a %b %e %H:%M:%S %Y"
+
+% Appropriate date representation (%x)
+d_fmt   "%m/%d/%y"
+
+% Appropriate time representation (%X)
+t_fmt   "%H:%M:%S"
+
+% Appropriate AM/PM time representation (%r)
+t_fmt_ampm "%I:%M:%S %p"
+
+% Equivalent of AM/PM (%p)
+am_pm	"AM";"PM"
+
+% Appropriate date representation (date(1))
+date_fmt	"%a %b %e %H:%M:%S %Z %Y"
+END LC_TIME
+
+LC_MESSAGES
+% This is the POSIX Locale definition for
+% the LC_NUMERIC category.
+%
+yesexpr "^[yY]"
+noexpr  "^[nN]"
+yesstr  "Yes"
+nostr   "No"
+END LC_MESSAGES
+
+LC_PAPER
+% This is the ISO/IEC 14652 "i18n" definition for
+% the LC_PAPER category.
+% (A4 paper, this is also used in the built in C/POSIX
+% locale in glibc/locale/C-paper.c)
+height   297
+width    210
+END LC_PAPER
+
+LC_NAME
+% This is the ISO/IEC 14652 "i18n" definition for
+% the LC_NAME category.
+% (also used in the built in C/POSIX locale in glibc/locale/C-name.c)
+name_fmt    "%p%t%g%t%m%t%f"
+END LC_NAME
+
+LC_ADDRESS
+% This is the ISO/IEC 14652 "i18n" definition for
+% the LC_ADDRESS category.
+% (also used in the built in C/POSIX locale in glibc/locale/C-address.c)
+postal_fmt    "%a%N%f%N%d%N%b%N%s %h %e %r%N%C-%z %T%N%c%N"
+END LC_ADDRESS
+
+LC_TELEPHONE
+% This is the ISO/IEC 14652 "i18n" definition for
+% the LC_TELEPHONE category.
+% "+%c %a %l"
+tel_int_fmt    "+%c %a %l"
+% (also used in the built in C/POSIX locale in glibc/locale/C-telephone.c)
+END LC_TELEPHONE
+
+LC_MEASUREMENT
+% This is the ISO/IEC 14652 "i18n" definition for
+% the LC_MEASUREMENT category.
+% (same as in the built in C/POSIX locale in glibc/locale/C-measurement.c)
+%metric
+measurement    1
+END LC_MEASUREMENT
diff --git a/posix/Makefile b/posix/Makefile
index 059efb3..a522977 100644
--- a/posix/Makefile
+++ b/posix/Makefile
@@ -190,9 +190,19 @@ $(objpfx)wordexp-tst.out: wordexp-tst.sh $(objpfx)wordexp-test
 	$(evaluate-test)
 endif
 
-LOCALES := cs_CZ.UTF-8 da_DK.ISO-8859-1 de_DE.ISO-8859-1 de_DE.UTF-8 \
-	   en_US.UTF-8 es_US.ISO-8859-1 es_US.UTF-8 ja_JP.EUC-JP tr_TR.UTF-8 \
-	   cs_CZ.ISO-8859-2
+LOCALES := \
+	cs_CZ.ISO-8859-2 \
+	cs_CZ.UTF-8 \
+	C.UTF-8 \
+	da_DK.ISO-8859-1 \
+	de_DE.ISO-8859-1 \
+	de_DE.UTF-8 \
+	en_US.UTF-8 \
+	es_US.ISO-8859-1 \
+	es_US.UTF-8 \
+	ja_JP.EUC-JP \
+	tr_TR.UTF-8 \
+	# LOCALES
 include ../gen-locales.mk
 
 $(objpfx)bug-regex1.out: $(gen-locales)
diff --git a/posix/bug-regex1.c b/posix/bug-regex1.c
index b8cf97c..99357e3 100644
--- a/posix/bug-regex1.c
+++ b/posix/bug-regex1.c
@@ -40,6 +40,26 @@ main (void)
 	puts (" -> OK");
     }
 
+  puts ("in C.UTF-8 locale");
+  setlocale (LC_ALL, "C.UTF-8");
+  s = re_compile_pattern ("[an\371]*n", 7, &regex);
+  if (s != NULL)
+    {
+      puts ("re_compile_pattern return non-NULL value");
+      result = 1;
+    }
+  else
+    {
+      match = re_match (&regex, "an", 2, 0, &regs);
+      if (match != 2)
+	{
+	  printf ("re_match returned %d, expected 2\n", match);
+	  result = 1;
+	}
+      else
+	puts (" -> OK");
+    }
+
   puts ("in de_DE.ISO-8859-1 locale");
   setlocale (LC_ALL, "de_DE.ISO-8859-1");
   s = re_compile_pattern ("[an\371]*n", 7, &regex);
diff --git a/posix/bug-regex19.c b/posix/bug-regex19.c
index 001827c..44f6ab6 100644
--- a/posix/bug-regex19.c
+++ b/posix/bug-regex19.c
@@ -24,6 +24,7 @@
 #include <string.h>
 #include <locale.h>
 #include <libc-diag.h>
+#include <support/support.h>
 
 #define BRE RE_SYNTAX_POSIX_BASIC
 #define ERE RE_SYNTAX_POSIX_EXTENDED
@@ -406,8 +407,8 @@ do_mb_tests (const struct test_s *test)
   return 0;
 }
 
-int
-main (void)
+static int
+do_test (void)
 {
   size_t i;
   int ret = 0;
@@ -416,20 +417,17 @@ main (void)
 
   for (i = 0; i < sizeof (tests) / sizeof (tests[0]); ++i)
     {
-      if (setlocale (LC_ALL, "de_DE.ISO-8859-1") == NULL)
-	{
-	  puts ("setlocale de_DE.ISO-8859-1 failed");
-	  ret = 1;
-	}
+      xsetlocale (LC_ALL, "de_DE.ISO-8859-1");
       ret |= do_one_test (&tests[i], "");
-      if (setlocale (LC_ALL, "de_DE.UTF-8") == NULL)
-	{
-	  puts ("setlocale de_DE.UTF-8 failed");
-	  ret = 1;
-	}
+      xsetlocale (LC_ALL, "de_DE.UTF-8");
+      ret |= do_one_test (&tests[i], "UTF-8 ");
+      ret |= do_mb_tests (&tests[i]);
+      xsetlocale (LC_ALL, "C.UTF-8");
       ret |= do_one_test (&tests[i], "UTF-8 ");
       ret |= do_mb_tests (&tests[i]);
     }
 
   return ret;
 }
+
+#include <support/test-driver.c>
diff --git a/posix/bug-regex4.c b/posix/bug-regex4.c
index 86901ec..3b63d7d 100644
--- a/posix/bug-regex4.c
+++ b/posix/bug-regex4.c
@@ -31,6 +31,7 @@ main (void)
 
   memset (&regex, '\0', sizeof (regex));
 
+  printf ("INFO: Checking C.\n");
   setlocale (LC_ALL, "C");
 
   s = re_compile_pattern ("ab[cde]", 7, &regex);
@@ -54,5 +55,29 @@ main (void)
 	puts (" -> OK");
     }
 
+  printf ("INFO: Checking C.UTF-8.\n");
+  setlocale (LC_ALL, "C.UTF-8");
+
+  s = re_compile_pattern ("ab[cde]", 7, &regex);
+  if (s != NULL)
+    {
+      puts ("re_compile_pattern returned non-NULL value");
+      result = 1;
+    }
+  else
+    {
+      match[0] = re_search_2 (&regex, "xyabez", 6, "", 0, 1, 5, NULL, 6);
+      match[1] = re_search_2 (&regex, NULL, 0, "abc", 3, 0, 3, NULL, 3);
+      match[2] = re_search_2 (&regex, "xya", 3, "bd", 2, 2, 3, NULL, 5);
+      if (match[0] != 2 || match[1] != 0 || match[2] != 2)
+	{
+	  printf ("re_search_2 returned %d,%d,%d, expected 2,0,2\n",
+		  match[0], match[1], match[2]);
+	  result = 1;
+	}
+      else
+	puts (" -> OK");
+    }
+
   return result;
 }
diff --git a/posix/bug-regex6.c b/posix/bug-regex6.c
index 324bd51..145f007 100644
--- a/posix/bug-regex6.c
+++ b/posix/bug-regex6.c
@@ -29,7 +29,7 @@ main (int argc, char *argv[])
   regex_t re;
   regmatch_t mat[10];
   int i, j, ret = 0;
-  const char *locales[] = { "C", "de_DE.UTF-8" };
+  const char *locales[] = { "C", "C.UTF-8", "de_DE.UTF-8" };
   const char *string = "http://www.regex.com/pattern/matching.html#intro";
   regmatch_t expect[10] = {
     { 0, 48 }, { 0, 5 }, { 0, 4 }, { 5, 20 }, { 7, 20 }, { 20, 42 },
diff --git a/posix/transbug.c b/posix/transbug.c
index d0983b4..b240177 100644
--- a/posix/transbug.c
+++ b/posix/transbug.c
@@ -116,16 +116,32 @@ do_test (void)
   static const char lower[] = "[[:lower:]]+";
   static const char upper[] = "[[:upper:]]+";
   struct re_registers regs[4];
+  int result = 0;
 
+#define CHECK(exp) \
+  if (exp) { puts (#exp); result = 1; }
+
+  printf ("INFO: Checking C.\n");
   setlocale (LC_ALL, "C");
 
   (void) re_set_syntax (RE_SYNTAX_GNU_AWK);
 
-  int result;
-#define CHECK(exp) \
-  if (exp) { puts (#exp); result = 1; }
+  result |= run_test (lower, regs);
+  result |= run_test (upper, &regs[2]);
+  if (! result)
+    {
+      CHECK (regs[0].start[0] != regs[2].start[0]);
+      CHECK (regs[0].end[0] != regs[2].end[0]);
+      CHECK (regs[1].start[0] != regs[3].start[0]);
+      CHECK (regs[1].end[0] != regs[3].end[0]);
+    }
+
+  printf ("INFO: Checking C.UTF-8.\n");
+  setlocale (LC_ALL, "C.UTF-8");
+
+  (void) re_set_syntax (RE_SYNTAX_GNU_AWK);
 
-  result = run_test (lower, regs);
+  result |= run_test (lower, regs);
   result |= run_test (upper, &regs[2]);
   if (! result)
     {
diff --git a/posix/tst-fnmatch.input b/posix/tst-fnmatch.input
index 9d07168..837fa2c 100644
--- a/posix/tst-fnmatch.input
+++ b/posix/tst-fnmatch.input
@@ -472,6 +472,397 @@ C		"\\"			"[Z-\\]]"	       0
 C		"]"			"[Z-\\]]"	       0
 C		"-"			"[Z-\\]]"	       NOMATCH
 
+# B.6 004(C)
+C.UTF-8		 "!#%+,-./01234567889"	"!#%+,-./01234567889"  0
+C.UTF-8		 ":;=@ABCDEFGHIJKLMNO"	":;=@ABCDEFGHIJKLMNO"  0
+C.UTF-8		 "PQRSTUVWXYZ]abcdefg"	"PQRSTUVWXYZ]abcdefg"  0
+C.UTF-8		 "hijklmnopqrstuvwxyz"	"hijklmnopqrstuvwxyz"  0
+C.UTF-8		 "^_{}~"		"^_{}~"		       0
+
+# B.6 005(C)
+C.UTF-8		 "\"$&'()"		"\\\"\\$\\&\\'\\(\\)"  0
+C.UTF-8		 "*?[\\`|"		"\\*\\?\\[\\\\\\`\\|"  0
+C.UTF-8		 "<>"			"\\<\\>"	       0
+
+# B.6 006(C)
+C.UTF-8		 "?*["			"[?*[][?*[][?*[]"      0
+C.UTF-8		 "a/b"			"?/b"		       0
+
+# B.6 007(C)
+C.UTF-8		 "a/b"			"a?b"		       0
+C.UTF-8		 "a/b"			"a/?"		       0
+C.UTF-8		 "aa/b"			"?/b"		       NOMATCH
+C.UTF-8		 "aa/b"			"a?b"		       NOMATCH
+C.UTF-8		 "a/bb"			"a/?"		       NOMATCH
+
+# B.6 009(C)
+C.UTF-8		 "abc"			"[abc]"		       NOMATCH
+C.UTF-8		 "x"			"[abc]"		       NOMATCH
+C.UTF-8		 "a"			"[abc]"		       0
+C.UTF-8		 "["			"[[abc]"	       0
+C.UTF-8		 "a"			"[][abc]"	       0
+C.UTF-8		 "a]"			"[]a]]"		       0
+
+# B.6 010(C)
+C.UTF-8		 "xyz"			"[!abc]"	       NOMATCH
+C.UTF-8		 "x"			"[!abc]"	       0
+C.UTF-8		 "a"			"[!abc]"	       NOMATCH
+
+# B.6 011(C)
+C.UTF-8		 "]"			"[][abc]"	       0
+C.UTF-8		 "abc]"			"[][abc]"	       NOMATCH
+C.UTF-8		 "[]abc"		"[][]abc"	       NOMATCH
+C.UTF-8		 "]"			"[!]]"		       NOMATCH
+C.UTF-8		 "aa]"			"[!]a]"		       NOMATCH
+C.UTF-8		 "]"			"[!a]"		       0
+C.UTF-8		 "]]"			"[!a]]"		       0
+
+# B.6 012(C)
+C.UTF-8		 "a"			"[[.a.]]"	       0
+C.UTF-8		 "-"			"[[.-.]]"	       0
+C.UTF-8		 "-"			"[[.-.][.].]]"	       0
+C.UTF-8		 "-"			"[[.].][.-.]]"	       0
+C.UTF-8		 "-"			"[[.-.][=u=]]"	       0
+C.UTF-8		 "-"			"[[.-.][:alpha:]]"     0
+C.UTF-8		 "a"			"[![.a.]]"	       NOMATCH
+
+# B.6 013(C)
+C.UTF-8		 "a"			"[[.b.]]"	       NOMATCH
+C.UTF-8		 "a"			"[[.b.][.c.]]"	       NOMATCH
+C.UTF-8		 "a"			"[[.b.][=b=]]"	       NOMATCH
+
+
+# B.6 015(C)
+C.UTF-8		 "a"			"[[=a=]]"	       0
+C.UTF-8		 "b"			"[[=a=]b]"	       0
+C.UTF-8		 "b"			"[[=a=][=b=]]"	       0
+C.UTF-8		 "a"			"[[=a=][=b=]]"	       0
+C.UTF-8		 "a"			"[[=a=][.b.]]"	       0
+C.UTF-8		 "a"			"[[=a=][:digit:]]"     0
+
+# B.6 016(C)
+C.UTF-8		 "="			"[[=a=]b]"	       NOMATCH
+C.UTF-8		 "]"			"[[=a=]b]"	       NOMATCH
+C.UTF-8		 "a"			"[[=b=][=c=]]"	       NOMATCH
+C.UTF-8		 "a"			"[[=b=][.].]]"	       NOMATCH
+C.UTF-8		 "a"			"[[=b=][:digit:]]"     NOMATCH
+
+# B.6 017(C)
+C.UTF-8		 "a"			"[[:alnum:]]"	       0
+C.UTF-8		 "a"			"[![:alnum:]]"	       NOMATCH
+C.UTF-8		 "-"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "a]a"			"[[:alnum:]]a"	       NOMATCH
+C.UTF-8		 "-"			"[[:alnum:]-]"	       0
+C.UTF-8		 "aa"			"[[:alnum:]]a"	       0
+C.UTF-8		 "-"			"[![:alnum:]]"	       0
+C.UTF-8		 "]"			"[!][:alnum:]]"	       NOMATCH
+C.UTF-8		 "["			"[![:alnum:][]"	       NOMATCH
+C.UTF-8		 "a"			"[[:alnum:]]"	       0
+C.UTF-8		 "b"			"[[:alnum:]]"	       0
+C.UTF-8		 "c"			"[[:alnum:]]"	       0
+C.UTF-8		 "d"			"[[:alnum:]]"	       0
+C.UTF-8		 "e"			"[[:alnum:]]"	       0
+C.UTF-8		 "f"			"[[:alnum:]]"	       0
+C.UTF-8		 "g"			"[[:alnum:]]"	       0
+C.UTF-8		 "h"			"[[:alnum:]]"	       0
+C.UTF-8		 "i"			"[[:alnum:]]"	       0
+C.UTF-8		 "j"			"[[:alnum:]]"	       0
+C.UTF-8		 "k"			"[[:alnum:]]"	       0
+C.UTF-8		 "l"			"[[:alnum:]]"	       0
+C.UTF-8		 "m"			"[[:alnum:]]"	       0
+C.UTF-8		 "n"			"[[:alnum:]]"	       0
+C.UTF-8		 "o"			"[[:alnum:]]"	       0
+C.UTF-8		 "p"			"[[:alnum:]]"	       0
+C.UTF-8		 "q"			"[[:alnum:]]"	       0
+C.UTF-8		 "r"			"[[:alnum:]]"	       0
+C.UTF-8		 "s"			"[[:alnum:]]"	       0
+C.UTF-8		 "t"			"[[:alnum:]]"	       0
+C.UTF-8		 "u"			"[[:alnum:]]"	       0
+C.UTF-8		 "v"			"[[:alnum:]]"	       0
+C.UTF-8		 "w"			"[[:alnum:]]"	       0
+C.UTF-8		 "x"			"[[:alnum:]]"	       0
+C.UTF-8		 "y"			"[[:alnum:]]"	       0
+C.UTF-8		 "z"			"[[:alnum:]]"	       0
+C.UTF-8		 "A"			"[[:alnum:]]"	       0
+C.UTF-8		 "B"			"[[:alnum:]]"	       0
+C.UTF-8		 "C"			"[[:alnum:]]"	       0
+C.UTF-8		 "D"			"[[:alnum:]]"	       0
+C.UTF-8		 "E"			"[[:alnum:]]"	       0
+C.UTF-8		 "F"			"[[:alnum:]]"	       0
+C.UTF-8		 "G"			"[[:alnum:]]"	       0
+C.UTF-8		 "H"			"[[:alnum:]]"	       0
+C.UTF-8		 "I"			"[[:alnum:]]"	       0
+C.UTF-8		 "J"			"[[:alnum:]]"	       0
+C.UTF-8		 "K"			"[[:alnum:]]"	       0
+C.UTF-8		 "L"			"[[:alnum:]]"	       0
+C.UTF-8		 "M"			"[[:alnum:]]"	       0
+C.UTF-8		 "N"			"[[:alnum:]]"	       0
+C.UTF-8		 "O"			"[[:alnum:]]"	       0
+C.UTF-8		 "P"			"[[:alnum:]]"	       0
+C.UTF-8		 "Q"			"[[:alnum:]]"	       0
+C.UTF-8		 "R"			"[[:alnum:]]"	       0
+C.UTF-8		 "S"			"[[:alnum:]]"	       0
+C.UTF-8		 "T"			"[[:alnum:]]"	       0
+C.UTF-8		 "U"			"[[:alnum:]]"	       0
+C.UTF-8		 "V"			"[[:alnum:]]"	       0
+C.UTF-8		 "W"			"[[:alnum:]]"	       0
+C.UTF-8		 "X"			"[[:alnum:]]"	       0
+C.UTF-8		 "Y"			"[[:alnum:]]"	       0
+C.UTF-8		 "Z"			"[[:alnum:]]"	       0
+C.UTF-8		 "0"			"[[:alnum:]]"	       0
+C.UTF-8		 "1"			"[[:alnum:]]"	       0
+C.UTF-8		 "2"			"[[:alnum:]]"	       0
+C.UTF-8		 "3"			"[[:alnum:]]"	       0
+C.UTF-8		 "4"			"[[:alnum:]]"	       0
+C.UTF-8		 "5"			"[[:alnum:]]"	       0
+C.UTF-8		 "6"			"[[:alnum:]]"	       0
+C.UTF-8		 "7"			"[[:alnum:]]"	       0
+C.UTF-8		 "8"			"[[:alnum:]]"	       0
+C.UTF-8		 "9"			"[[:alnum:]]"	       0
+C.UTF-8		 "!"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "#"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "%"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "+"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 ","			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "-"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "."			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "/"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 ":"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 ";"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "="			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "@"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "["			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "\\"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "]"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "^"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "_"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "{"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "}"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "~"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "\""			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "$"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "&"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "'"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "("			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 ")"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "*"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "?"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "`"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "|"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "<"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 ">"			"[[:alnum:]]"	       NOMATCH
+C.UTF-8		 "\t"			"[[:cntrl:]]"	       0
+C.UTF-8		 "t"			"[[:cntrl:]]"	       NOMATCH
+C.UTF-8		 "t"			"[[:lower:]]"	       0
+C.UTF-8		 "\t"			"[[:lower:]]"	       NOMATCH
+C.UTF-8		 "T"			"[[:lower:]]"	       NOMATCH
+C.UTF-8		 "\t"			"[[:space:]]"	       0
+C.UTF-8		 "t"			"[[:space:]]"	       NOMATCH
+C.UTF-8		 "t"			"[[:alpha:]]"	       0
+C.UTF-8		 "\t"			"[[:alpha:]]"	       NOMATCH
+C.UTF-8		 "0"			"[[:digit:]]"	       0
+C.UTF-8		 "\t"			"[[:digit:]]"	       NOMATCH
+C.UTF-8		 "t"			"[[:digit:]]"	       NOMATCH
+C.UTF-8		 "\t"			"[[:print:]]"	       NOMATCH
+C.UTF-8		 "t"			"[[:print:]]"	       0
+C.UTF-8		 "T"			"[[:upper:]]"	       0
+C.UTF-8		 "\t"			"[[:upper:]]"	       NOMATCH
+C.UTF-8		 "t"			"[[:upper:]]"	       NOMATCH
+C.UTF-8		 "\t"			"[[:blank:]]"	       0
+C.UTF-8		 "t"			"[[:blank:]]"	       NOMATCH
+C.UTF-8		 "\t"			"[[:graph:]]"	       NOMATCH
+C.UTF-8		 "t"			"[[:graph:]]"	       0
+C.UTF-8		 "."			"[[:punct:]]"	       0
+C.UTF-8		 "t"			"[[:punct:]]"	       NOMATCH
+C.UTF-8		 "\t"			"[[:punct:]]"	       NOMATCH
+C.UTF-8		 "0"			"[[:xdigit:]]"	       0
+C.UTF-8		 "\t"			"[[:xdigit:]]"	       NOMATCH
+C.UTF-8		 "a"			"[[:xdigit:]]"	       0
+C.UTF-8		 "A"			"[[:xdigit:]]"	       0
+C.UTF-8		 "t"			"[[:xdigit:]]"	       NOMATCH
+C.UTF-8		 "a"			"[[alpha]]"	       NOMATCH
+C.UTF-8		 "a"			"[[alpha:]]"	       NOMATCH
+C.UTF-8		 "a]"			"[[alpha]]"	       0
+C.UTF-8		 "a]"			"[[alpha:]]"	       0
+C.UTF-8		 "a"			"[[:alpha:][.b.]]"     0
+C.UTF-8		 "a"			"[[:alpha:][=b=]]"     0
+C.UTF-8		 "a"			"[[:alpha:][:digit:]]" 0
+C.UTF-8		 "a"			"[[:digit:][:alpha:]]" 0
+
+# B.6 018(C)
+C.UTF-8		 "a"			"[a-c]"		       0
+C.UTF-8		 "b"			"[a-c]"		       0
+C.UTF-8		 "c"			"[a-c]"		       0
+C.UTF-8		 "a"			"[b-c]"		       NOMATCH
+C.UTF-8		 "d"			"[b-c]"		       NOMATCH
+C.UTF-8		 "B"			"[a-c]"		       NOMATCH
+C.UTF-8		 "b"			"[A-C]"		       NOMATCH
+C.UTF-8		 ""			"[a-c]"		       NOMATCH
+C.UTF-8		 "as"			"[a-ca-z]"	       NOMATCH
+C.UTF-8		 "a"			"[[.a.]-c]"	       0
+C.UTF-8		 "a"			"[a-[.c.]]"	       0
+C.UTF-8		 "a"			"[[.a.]-[.c.]]"	       0
+C.UTF-8		 "b"			"[[.a.]-c]"	       0
+C.UTF-8		 "b"			"[a-[.c.]]"	       0
+C.UTF-8		 "b"			"[[.a.]-[.c.]]"	       0
+C.UTF-8		 "c"			"[[.a.]-c]"	       0
+C.UTF-8		 "c"			"[a-[.c.]]"	       0
+C.UTF-8		 "c"			"[[.a.]-[.c.]]"	       0
+C.UTF-8		 "d"			"[[.a.]-c]"	       NOMATCH
+C.UTF-8		 "d"			"[a-[.c.]]"	       NOMATCH
+C.UTF-8		 "d"			"[[.a.]-[.c.]]"	       NOMATCH
+
+# B.6 019(C)
+C.UTF-8		 "a"			"[c-a]"		       NOMATCH
+C.UTF-8		 "a"			"[[.c.]-a]"	       NOMATCH
+C.UTF-8		 "a"			"[c-[.a.]]"	       NOMATCH
+C.UTF-8		 "a"			"[[.c.]-[.a.]]"	       NOMATCH
+C.UTF-8		 "c"			"[c-a]"		       NOMATCH
+C.UTF-8		 "c"			"[[.c.]-a]"	       NOMATCH
+C.UTF-8		 "c"			"[c-[.a.]]"	       NOMATCH
+C.UTF-8		 "c"			"[[.c.]-[.a.]]"	       NOMATCH
+
+# B.6 020(C)
+C.UTF-8		 "a"			"[a-c0-9]"	       0
+C.UTF-8		 "d"			"[a-c0-9]"	       NOMATCH
+C.UTF-8		 "B"			"[a-c0-9]"	       NOMATCH
+
+# B.6 021(C)
+C.UTF-8		 "-"			"[-a]"		       0
+C.UTF-8		 "a"			"[-b]"		       NOMATCH
+C.UTF-8		 "-"			"[!-a]"		       NOMATCH
+C.UTF-8		 "a"			"[!-b]"		       0
+C.UTF-8		 "-"			"[a-c-0-9]"	       0
+C.UTF-8		 "b"			"[a-c-0-9]"	       0
+C.UTF-8		 "a:"			"a[0-9-a]"	       NOMATCH
+C.UTF-8		 "a:"			"a[09-a]"	       0
+
+# B.6 024(C)
+C.UTF-8		 ""			"*"		       0
+C.UTF-8		 "asd/sdf"		"*"		       0
+
+# B.6 025(C)
+C.UTF-8		 "as"			"[a-c][a-z]"	       0
+C.UTF-8		 "as"			"??"		       0
+
+# B.6 026(C)
+C.UTF-8		 "asd/sdf"		"as*df"		       0
+C.UTF-8		 "asd/sdf"		"as*"		       0
+C.UTF-8		 "asd/sdf"		"*df"		       0
+C.UTF-8		 "asd/sdf"		"as*dg"		       NOMATCH
+C.UTF-8		 "asdf"			"as*df"		       0
+C.UTF-8		 "asdf"			"as*df?"	       NOMATCH
+C.UTF-8		 "asdf"			"as*??"		       0
+C.UTF-8		 "asdf"			"a*???"		       0
+C.UTF-8		 "asdf"			"*????"		       0
+C.UTF-8		 "asdf"			"????*"		       0
+C.UTF-8		 "asdf"			"??*?"		       0
+
+# B.6 027(C)
+C.UTF-8		 "/"			"/"		       0
+C.UTF-8		 "/"			"/*"		       0
+C.UTF-8		 "/"			"*/"		       0
+C.UTF-8		 "/"			"/?"		       NOMATCH
+C.UTF-8		 "/"			"?/"		       NOMATCH
+C.UTF-8		 "/"			"?"		       0
+C.UTF-8		 "."			"?"		       0
+C.UTF-8		 "/."			"??"		       0
+C.UTF-8		 "/"			"[!a-c]"	       0
+C.UTF-8		 "."			"[!a-c]"	       0
+
+# B.6 029(C)
+C.UTF-8		 "/"			"/"		       0       PATHNAME
+C.UTF-8		 "//"			"//"		       0       PATHNAME
+C.UTF-8		 "/.a"			"/*"		       0       PATHNAME
+C.UTF-8		 "/.a"			"/?a"		       0       PATHNAME
+C.UTF-8		 "/.a"			"/[!a-z]a"	       0       PATHNAME
+C.UTF-8		 "/.a/.b"		"/*/?b"		       0       PATHNAME
+
+# B.6 030(C)
+C.UTF-8		 "/"			"?"		       NOMATCH PATHNAME
+C.UTF-8		 "/"			"*"		       NOMATCH PATHNAME
+C.UTF-8		 "a/b"			"a?b"		       NOMATCH PATHNAME
+C.UTF-8		 "/.a/.b"		"/*b"		       NOMATCH PATHNAME
+
+# B.6 031(C)
+C.UTF-8		 "/$"			"\\/\\$"	       0
+C.UTF-8		 "/["			"\\/\\["	       0
+C.UTF-8		 "/["			"\\/["		       0
+C.UTF-8		 "/[]"			"\\/\\[]"	       0
+
+# B.6 032(C)
+C.UTF-8		 "/$"			"\\/\\$"	       NOMATCH NOESCAPE
+C.UTF-8		 "/\\$"			"\\/\\$"	       NOMATCH NOESCAPE
+C.UTF-8		 "\\/\\$"		"\\/\\$"	       0       NOESCAPE
+
+# B.6 033(C)
+C.UTF-8		 ".asd"			".*"		       0       PERIOD
+C.UTF-8		 "/.asd"		"*"		       0       PERIOD
+C.UTF-8		 "/as/.df"		"*/?*f"		       0       PERIOD
+C.UTF-8		 "..asd"		".[!a-z]*"	       0       PERIOD
+
+# B.6 034(C)
+C.UTF-8		 ".asd"			"*"		       NOMATCH PERIOD
+C.UTF-8		 ".asd"			"?asd"		       NOMATCH PERIOD
+C.UTF-8		 ".asd"			"[!a-z]*"	       NOMATCH PERIOD
+
+# B.6 035(C)
+C.UTF-8		 "/."			"/."		       0       PATHNAME|PERIOD
+C.UTF-8		 "/.a./.b."		"/.*/.*"	       0       PATHNAME|PERIOD
+C.UTF-8		 "/.a./.b."		"/.??/.??"	       0       PATHNAME|PERIOD
+
+# B.6 036(C)
+C.UTF-8		 "/."			"*"		       NOMATCH PATHNAME|PERIOD
+C.UTF-8		 "/."			"/*"		       NOMATCH PATHNAME|PERIOD
+C.UTF-8		 "/."			"/?"		       NOMATCH PATHNAME|PERIOD
+C.UTF-8		 "/."			"/[!a-z]"	       NOMATCH PATHNAME|PERIOD
+C.UTF-8		 "/a./.b."		"/*/*"		       NOMATCH PATHNAME|PERIOD
+C.UTF-8		 "/a./.b."		"/??/???"	       NOMATCH PATHNAME|PERIOD
+
+# Some home-grown tests.
+C.UTF-8		"foobar"		"foo*[abc]z"	       NOMATCH
+C.UTF-8		"foobaz"		"foo*[abc][xyz]"       0
+C.UTF-8		"foobaz"		"foo?*[abc][xyz]"      0
+C.UTF-8		"foobaz"		"foo?*[abc][x/yz]"     0
+C.UTF-8		"foobaz"		"foo?*[abc]/[xyz]"     NOMATCH PATHNAME
+C.UTF-8		"a"			"a/"                   NOMATCH PATHNAME
+C.UTF-8		"a/"			"a"		       NOMATCH PATHNAME
+C.UTF-8		"//a"			"/a"		       NOMATCH PATHNAME
+C.UTF-8		"/a"			"//a"		       NOMATCH PATHNAME
+C.UTF-8		"az"			"[a-]z"		       0
+C.UTF-8		"bz"			"[ab-]z"	       0
+C.UTF-8		"cz"			"[ab-]z"	       NOMATCH
+C.UTF-8		"-z"			"[ab-]z"	       0
+C.UTF-8		"az"			"[-a]z"		       0
+C.UTF-8		"bz"			"[-ab]z"	       0
+C.UTF-8		"cz"			"[-ab]z"	       NOMATCH
+C.UTF-8		"-z"			"[-ab]z"	       0
+C.UTF-8		"\\"			"[\\\\-a]"	       0
+C.UTF-8		"_"			"[\\\\-a]"	       0
+C.UTF-8		"a"			"[\\\\-a]"	       0
+C.UTF-8		"-"			"[\\\\-a]"	       NOMATCH
+C.UTF-8		"\\"			"[\\]-a]"	       NOMATCH
+C.UTF-8		"_"			"[\\]-a]"	       0
+C.UTF-8		"a"			"[\\]-a]"	       0
+C.UTF-8		"]"			"[\\]-a]"	       0
+C.UTF-8		"-"			"[\\]-a]"	       NOMATCH
+C.UTF-8		"\\"			"[!\\\\-a]"	       NOMATCH
+C.UTF-8		"_"			"[!\\\\-a]"	       NOMATCH
+C.UTF-8		"a"			"[!\\\\-a]"	       NOMATCH
+C.UTF-8		"-"			"[!\\\\-a]"	       0
+C.UTF-8		"!"			"[\\!-]"	       0
+C.UTF-8		"-"			"[\\!-]"	       0
+C.UTF-8		"\\"			"[\\!-]"	       NOMATCH
+C.UTF-8		"Z"			"[Z-\\\\]"	       0
+C.UTF-8		"["			"[Z-\\\\]"	       0
+C.UTF-8		"\\"			"[Z-\\\\]"	       0
+C.UTF-8		"-"			"[Z-\\\\]"	       NOMATCH
+C.UTF-8		"Z"			"[Z-\\]]"	       0
+C.UTF-8		"["			"[Z-\\]]"	       0
+C.UTF-8		"\\"			"[Z-\\]]"	       0
+C.UTF-8		"]"			"[Z-\\]]"	       0
+C.UTF-8		"-"			"[Z-\\]]"	       NOMATCH
+
 # Following are tests outside the scope of IEEE 2003.2 since they are using
 # locales other than the C locale.  The main focus of the tests is on the
 # handling of ranges and the recognition of character (vs bytes).
@@ -677,7 +1068,6 @@ C		 "x/y"			"*"		       0       PATHNAME|LEADING_DIR
 C		 "x/y/z"		"*"		       0       PATHNAME|LEADING_DIR
 C		 "x"			"*x"		       0       PATHNAME|LEADING_DIR
 
-en_US.UTF-8	 "\366.csv"		"*.csv"                0
 C		 "x/y"			"*x"		       0       PATHNAME|LEADING_DIR
 C		 "x/y/z"		"*x"		       0       PATHNAME|LEADING_DIR
 C		 "x"			"x*"		       0       PATHNAME|LEADING_DIR
@@ -693,6 +1083,33 @@ C		 "x"			"x?y"		       NOMATCH PATHNAME|LEADING_DIR
 C		 "x/y"			"x?y"		       NOMATCH PATHNAME|LEADING_DIR
 C		 "x/y/z"		"x?y"		       NOMATCH PATHNAME|LEADING_DIR
 
+# Duplicate the "Test of GNU extensions." tests but for C.UTF-8.
+C.UTF-8		 "x"			"x"		       0       PATHNAME|LEADING_DIR
+C.UTF-8		 "x/y"			"x"		       0       PATHNAME|LEADING_DIR
+C.UTF-8		 "x/y/z"		"x"		       0       PATHNAME|LEADING_DIR
+C.UTF-8		 "x"			"*"		       0       PATHNAME|LEADING_DIR
+C.UTF-8		 "x/y"			"*"		       0       PATHNAME|LEADING_DIR
+C.UTF-8		 "x/y/z"		"*"		       0       PATHNAME|LEADING_DIR
+C.UTF-8		 "x"			"*x"		       0       PATHNAME|LEADING_DIR
+
+C.UTF-8		 "x/y"			"*x"		       0       PATHNAME|LEADING_DIR
+C.UTF-8		 "x/y/z"		"*x"		       0       PATHNAME|LEADING_DIR
+C.UTF-8		 "x"			"x*"		       0       PATHNAME|LEADING_DIR
+C.UTF-8		 "x/y"			"x*"		       0       PATHNAME|LEADING_DIR
+C.UTF-8		 "x/y/z"		"x*"		       0       PATHNAME|LEADING_DIR
+C.UTF-8		 "x"			"a"		       NOMATCH PATHNAME|LEADING_DIR
+C.UTF-8		 "x/y"			"a"		       NOMATCH PATHNAME|LEADING_DIR
+C.UTF-8		 "x/y/z"		"a"		       NOMATCH PATHNAME|LEADING_DIR
+C.UTF-8		 "x"			"x/y"		       NOMATCH PATHNAME|LEADING_DIR
+C.UTF-8		 "x/y"			"x/y"		       0       PATHNAME|LEADING_DIR
+C.UTF-8		 "x/y/z"		"x/y"		       0       PATHNAME|LEADING_DIR
+C.UTF-8		 "x"			"x?y"		       NOMATCH PATHNAME|LEADING_DIR
+C.UTF-8		 "x/y"			"x?y"		       NOMATCH PATHNAME|LEADING_DIR
+C.UTF-8		 "x/y/z"		"x?y"		       NOMATCH PATHNAME|LEADING_DIR
+
+# Bug 14185
+en_US.UTF-8	 "\366.csv"		"*.csv"                0
+
 # ksh style matching.
 C		"abcd"			"?@(a|b)*@(c)d"	       0       EXTMATCH
 C		"/dev/udp/129.22.8.102/45" "/dev/@(tcp|udp)/*/*" 0     PATHNAME|EXTMATCH
@@ -822,3 +1239,133 @@ C		""			""		       0
 C		""			""		       0       EXTMATCH
 C		""			"*([abc])"	       0       EXTMATCH
 C		""			"?([abc])"	       0       EXTMATCH
+
+# Duplicate the "ksh style matching." for C.UTF-8.
+C.UTF-8		"abcd"			"?@(a|b)*@(c)d"	       0       EXTMATCH
+C.UTF-8		"/dev/udp/129.22.8.102/45" "/dev/@(tcp|udp)/*/*" 0     PATHNAME|EXTMATCH
+C.UTF-8		"12"			"[1-9]*([0-9])"        0       EXTMATCH
+C.UTF-8		"12abc"			"[1-9]*([0-9])"        NOMATCH EXTMATCH
+C.UTF-8		"1"			"[1-9]*([0-9])"	       0       EXTMATCH
+C.UTF-8		"07"			"+([0-7])"	       0       EXTMATCH
+C.UTF-8		"0377"			"+([0-7])"	       0       EXTMATCH
+C.UTF-8		"09"			"+([0-7])"	       NOMATCH EXTMATCH
+C.UTF-8		"paragraph"		"para@(chute|graph)"   0       EXTMATCH
+C.UTF-8		"paramour"		"para@(chute|graph)"   NOMATCH EXTMATCH
+C.UTF-8		"para991"		"para?([345]|99)1"     0       EXTMATCH
+C.UTF-8		"para381"		"para?([345]|99)1"     NOMATCH EXTMATCH
+C.UTF-8		"paragraph"		"para*([0-9])"	       NOMATCH EXTMATCH
+C.UTF-8		"para"			"para*([0-9])"	       0       EXTMATCH
+C.UTF-8		"para13829383746592"	"para*([0-9])"	       0       EXTMATCH
+C.UTF-8		"paragraph"		"para+([0-9])"	       NOMATCH EXTMATCH
+C.UTF-8		"para"			"para+([0-9])"	       NOMATCH EXTMATCH
+C.UTF-8		"para987346523"		"para+([0-9])"	       0       EXTMATCH
+C.UTF-8		"paragraph"		"para!(*.[0-9])"       0       EXTMATCH
+C.UTF-8		"para.38"		"para!(*.[0-9])"       0       EXTMATCH
+C.UTF-8		"para.graph"		"para!(*.[0-9])"       0       EXTMATCH
+C.UTF-8		"para39"		"para!(*.[0-9])"       0       EXTMATCH
+C.UTF-8		""			"*(0|1|3|5|7|9)"       0       EXTMATCH
+C.UTF-8		"137577991"		"*(0|1|3|5|7|9)"       0       EXTMATCH
+C.UTF-8		"2468"			"*(0|1|3|5|7|9)"       NOMATCH EXTMATCH
+C.UTF-8		"1358"			"*(0|1|3|5|7|9)"       NOMATCH EXTMATCH
+C.UTF-8		"file.c"		"*.c?(c)"	       0       EXTMATCH
+C.UTF-8		"file.C"		"*.c?(c)"	       NOMATCH EXTMATCH
+C.UTF-8		"file.cc"		"*.c?(c)"	       0       EXTMATCH
+C.UTF-8		"file.ccc"		"*.c?(c)"	       NOMATCH EXTMATCH
+C.UTF-8		"parse.y"		"!(*.c|*.h|Makefile.in|config*|README)" 0 EXTMATCH
+C.UTF-8		"shell.c"		"!(*.c|*.h|Makefile.in|config*|README)" NOMATCH EXTMATCH
+C.UTF-8		"Makefile"		"!(*.c|*.h|Makefile.in|config*|README)" 0 EXTMATCH
+C.UTF-8		"VMS.FILE;1"		"*\;[1-9]*([0-9])"     0       EXTMATCH
+C.UTF-8		"VMS.FILE;0"		"*\;[1-9]*([0-9])"     NOMATCH EXTMATCH
+C.UTF-8		"VMS.FILE;"		"*\;[1-9]*([0-9])"     NOMATCH EXTMATCH
+C.UTF-8		"VMS.FILE;139"		"*\;[1-9]*([0-9])"     0       EXTMATCH
+C.UTF-8		"VMS.FILE;1N"		"*\;[1-9]*([0-9])"     NOMATCH EXTMATCH
+C.UTF-8		"abcfefg"		"ab**(e|f)"	       0       EXTMATCH
+C.UTF-8		"abcfefg"		"ab**(e|f)g"	       0       EXTMATCH
+C.UTF-8		"ab"			"ab*+(e|f)"	       NOMATCH EXTMATCH
+C.UTF-8		"abef"			"ab***ef"	       0       EXTMATCH
+C.UTF-8		"abef"			"ab**"		       0       EXTMATCH
+C.UTF-8		"fofo"			"*(f*(o))"	       0       EXTMATCH
+C.UTF-8		"ffo"			"*(f*(o))"	       0       EXTMATCH
+C.UTF-8		"foooofo"		"*(f*(o))"	       0       EXTMATCH
+C.UTF-8		"foooofof"		"*(f*(o))"	       0       EXTMATCH
+C.UTF-8		"fooofoofofooo"		"*(f*(o))"	       0       EXTMATCH
+C.UTF-8		"foooofof"		"*(f+(o))"	       NOMATCH EXTMATCH
+C.UTF-8		"xfoooofof"		"*(f*(o))"	       NOMATCH EXTMATCH
+C.UTF-8		"foooofofx"		"*(f*(o))"	       NOMATCH EXTMATCH
+C.UTF-8		"ofxoofxo"		"*(*(of*(o)x)o)"       0       EXTMATCH
+C.UTF-8		"ofooofoofofooo"	"*(f*(o))"	       NOMATCH EXTMATCH
+C.UTF-8		"foooxfooxfoxfooox"	"*(f*(o)x)"	       0       EXTMATCH
+C.UTF-8		"foooxfooxofoxfooox"	"*(f*(o)x)"	       NOMATCH EXTMATCH
+C.UTF-8		"foooxfooxfxfooox"	"*(f*(o)x)"	       0       EXTMATCH
+C.UTF-8		"ofxoofxo"		"*(*(of*(o)x)o)"       0       EXTMATCH
+C.UTF-8		"ofoooxoofxo"		"*(*(of*(o)x)o)"       0       EXTMATCH
+C.UTF-8		"ofoooxoofxoofoooxoofxo" "*(*(of*(o)x)o)"      0       EXTMATCH
+C.UTF-8		"ofoooxoofxoofoooxoofxoo" "*(*(of*(o)x)o)"     0       EXTMATCH
+C.UTF-8		"ofoooxoofxoofoooxoofxofo" "*(*(of*(o)x)o)"    NOMATCH EXTMATCH
+C.UTF-8		"ofoooxoofxoofoooxoofxooofxofxo" "*(*(of*(o)x)o)" 0    EXTMATCH
+C.UTF-8		"aac"			"*(@(a))a@(c)"	       0       EXTMATCH
+C.UTF-8		"ac"			"*(@(a))a@(c)"	       0       EXTMATCH
+C.UTF-8		"c"			"*(@(a))a@(c)"	       NOMATCH EXTMATCH
+C.UTF-8		"aaac"			"*(@(a))a@(c)"	       0       EXTMATCH
+C.UTF-8		"baaac"			"*(@(a))a@(c)"	       NOMATCH EXTMATCH
+C.UTF-8		"abcd"			"?@(a|b)*@(c)d"	       0       EXTMATCH
+C.UTF-8		"abcd"			"@(ab|a*@(b))*(c)d"    0       EXTMATCH
+C.UTF-8		"acd"			"@(ab|a*(b))*(c)d"     0       EXTMATCH
+C.UTF-8		"abbcd"			"@(ab|a*(b))*(c)d"     0       EXTMATCH
+C.UTF-8		"effgz"			"@(b+(c)d|e*(f)g?|?(h)i@(j|k))" 0 EXTMATCH
+C.UTF-8		"efgz"			"@(b+(c)d|e*(f)g?|?(h)i@(j|k))" 0 EXTMATCH
+C.UTF-8		"egz"			"@(b+(c)d|e*(f)g?|?(h)i@(j|k))" 0 EXTMATCH
+C.UTF-8		"egzefffgzbcdij"	"*(b+(c)d|e*(f)g?|?(h)i@(j|k))" 0 EXTMATCH
+C.UTF-8		"egz"			"@(b+(c)d|e+(f)g?|?(h)i@(j|k))" NOMATCH EXTMATCH
+C.UTF-8		"ofoofo"		"*(of+(o))"	       0       EXTMATCH
+C.UTF-8		"oxfoxoxfox"		"*(oxf+(ox))"	       0       EXTMATCH
+C.UTF-8		"oxfoxfox"		"*(oxf+(ox))"	       NOMATCH EXTMATCH
+C.UTF-8		"ofoofo"		"*(of+(o)|f)"	       0       EXTMATCH
+C.UTF-8		"foofoofo"		"@(foo|f|fo)*(f|of+(o))" 0     EXTMATCH
+C.UTF-8		"oofooofo"		"*(of|oof+(o))"	       0       EXTMATCH
+C.UTF-8		"fffooofoooooffoofffooofff" "*(*(f)*(o))"      0       EXTMATCH
+C.UTF-8		"fofoofoofofoo"		"*(fo|foo)"	       0       EXTMATCH
+C.UTF-8		"foo"			"!(x)"		       0       EXTMATCH
+C.UTF-8		"foo"			"!(x)*"		       0       EXTMATCH
+C.UTF-8		"foo"			"!(foo)"	       NOMATCH EXTMATCH
+C.UTF-8		"foo"			"!(foo)*"	       0       EXTMATCH
+C.UTF-8		"foobar"		"!(foo)"	       0       EXTMATCH
+C.UTF-8		"foobar"		"!(foo)*"	       0       EXTMATCH
+C.UTF-8		"moo.cow"		"!(*.*).!(*.*)"	       0       EXTMATCH
+C.UTF-8		"mad.moo.cow"		"!(*.*).!(*.*)"	       NOMATCH EXTMATCH
+C.UTF-8		"mucca.pazza"		"mu!(*(c))?.pa!(*(z))?" NOMATCH EXTMATCH
+C.UTF-8		"fff"			"!(f)"		       0       EXTMATCH
+C.UTF-8		"fff"			"*(!(f))"	       0       EXTMATCH
+C.UTF-8		"fff"			"+(!(f))"	       0       EXTMATCH
+C.UTF-8		"ooo"			"!(f)"		       0       EXTMATCH
+C.UTF-8		"ooo"			"*(!(f))"	       0       EXTMATCH
+C.UTF-8		"ooo"			"+(!(f))"	       0       EXTMATCH
+C.UTF-8		"foo"			"!(f)"		       0       EXTMATCH
+C.UTF-8		"foo"			"*(!(f))"	       0       EXTMATCH
+C.UTF-8		"foo"			"+(!(f))"	       0       EXTMATCH
+C.UTF-8		"f"			"!(f)"		       NOMATCH EXTMATCH
+C.UTF-8		"f"			"*(!(f))"	       NOMATCH EXTMATCH
+C.UTF-8		"f"			"+(!(f))"	       NOMATCH EXTMATCH
+C.UTF-8		"foot"			"@(!(z*)|*x)"	       0       EXTMATCH
+C.UTF-8		"zoot"			"@(!(z*)|*x)"	       NOMATCH EXTMATCH
+C.UTF-8		"foox"			"@(!(z*)|*x)"	       0       EXTMATCH
+C.UTF-8		"zoox"			"@(!(z*)|*x)"	       0       EXTMATCH
+C.UTF-8		"foo"			"*(!(foo))"	       0       EXTMATCH
+C.UTF-8		"foob"			"!(foo)b*"	       NOMATCH EXTMATCH
+C.UTF-8		"foobb"			"!(foo)b*"	       0       EXTMATCH
+C.UTF-8		"["			"*([a[])"	       0       EXTMATCH
+C.UTF-8		"]"			"*([]a[])"	       0       EXTMATCH
+C.UTF-8		"a"			"*([]a[])"	       0       EXTMATCH
+C.UTF-8		"b"			"*([!]a[])"	       0       EXTMATCH
+C.UTF-8		"["			"*([!]a[]|[[])"	       0       EXTMATCH
+C.UTF-8		"]"			"*([!]a[]|[]])"	       0       EXTMATCH
+C.UTF-8		"["			"!([!]a[])"	       0       EXTMATCH
+C.UTF-8		"]"			"!([!]a[])"	       0       EXTMATCH
+C.UTF-8		")"			"*([)])"	       0       EXTMATCH
+C.UTF-8		"*"			"*([*(])"	       0       EXTMATCH
+C.UTF-8		"abcd"			"*!(|a)cd"	       0       EXTMATCH
+C.UTF-8		"ab/.a"			"+([abc])/*"	       NOMATCH EXTMATCH|PATHNAME|PERIOD
+C.UTF-8		""			""		       0
+C.UTF-8		""			""		       0       EXTMATCH
+C.UTF-8		""			"*([abc])"	       0       EXTMATCH
+C.UTF-8		""			"?([abc])"	       0       EXTMATCH
diff --git a/posix/tst-regcomp-truncated.c b/posix/tst-regcomp-truncated.c
index 84195fc..da3f977 100644
--- a/posix/tst-regcomp-truncated.c
+++ b/posix/tst-regcomp-truncated.c
@@ -37,6 +37,7 @@
 static const char locales[][17] =
   {
     "C",
+    "C.UTF-8",
     "en_US.UTF-8",
     "de_DE.ISO-8859-1",
   };
diff --git a/posix/tst-regex.c b/posix/tst-regex.c
index e7c2b05..531128d 100644
--- a/posix/tst-regex.c
+++ b/posix/tst-regex.c
@@ -32,6 +32,7 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <regex.h>
+#include <support/support.h>
 
 
 #if defined _POSIX_CPUTIME && _POSIX_CPUTIME >= 0
@@ -58,7 +59,7 @@ do_test (void)
   const char *file;
   int fd;
   struct stat st;
-  int result;
+  int result = 0;
   char *inmem;
   char *outmem;
   size_t inlen;
@@ -123,7 +124,7 @@ do_test (void)
 
   /* Run the actual tests.  All tests are run in a single-byte and a
      multi-byte locale.  */
-  result = test_expr ("[äáàâéèêíìîñöóòôüúùû]", 4, 4);
+  result |= test_expr ("[äáàâéèêíìîñöóòôüúùû]", 4, 4);
   result |= test_expr ("G.ran", 2, 3);
   result |= test_expr ("G.\\{1\\}ran", 2, 3);
   result |= test_expr ("G.*ran", 3, 44);
@@ -143,19 +144,33 @@ do_test (void)
 static int
 test_expr (const char *expr, int expected, int expectedicase)
 {
-  int result;
+  int result = 0;
   char *inmem;
   char *outmem;
   size_t inlen;
   size_t outlen;
   char *uexpr;
 
-  /* First test: search with an UTF-8 locale.  */
-  if (setlocale (LC_ALL, "de_DE.UTF-8") == NULL)
-    error (EXIT_FAILURE, 0, "cannot set locale de_DE.UTF-8");
+  /* First test: search with basic C.UTF-8 locale.  */
+  printf ("INFO: Testing C.UTF-8.\n");
+  xsetlocale (LC_ALL, "C.UTF-8");
 
   printf ("\nTest \"%s\" with multi-byte locale\n", expr);
-  result = run_test (expr, mem, memlen, 0, expected);
+  result |= run_test (expr, mem, memlen, 0, expected);
+  printf ("\nTest \"%s\" with multi-byte locale, case insensitive\n", expr);
+  result |= run_test (expr, mem, memlen, 1, expectedicase);
+  printf ("\nTest \"%s\" backwards with multi-byte locale\n", expr);
+  result |= run_test_backwards (expr, mem, memlen, 0, expected);
+  printf ("\nTest \"%s\" backwards with multi-byte locale, case insensitive\n",
+	  expr);
+  result |= run_test_backwards (expr, mem, memlen, 1, expectedicase);
+
+  /* Second test: search with an UTF-8 locale.  */
+  printf ("INFO: Testing de_DE.UTF-8.\n");
+  xsetlocale (LC_ALL, "de_DE.UTF-8");
+
+  printf ("\nTest \"%s\" with multi-byte locale\n", expr);
+  result |= run_test (expr, mem, memlen, 0, expected);
   printf ("\nTest \"%s\" with multi-byte locale, case insensitive\n", expr);
   result |= run_test (expr, mem, memlen, 1, expectedicase);
   printf ("\nTest \"%s\" backwards with multi-byte locale\n", expr);
@@ -165,8 +180,8 @@ test_expr (const char *expr, int expected, int expectedicase)
   result |= run_test_backwards (expr, mem, memlen, 1, expectedicase);
 
   /* Second test: search with an ISO-8859-1 locale.  */
-  if (setlocale (LC_ALL, "de_DE.ISO-8859-1") == NULL)
-    error (EXIT_FAILURE, 0, "cannot set locale de_DE.ISO-8859-1");
+  printf ("INFO: Testing de_DE.ISO-8859-1.\n");
+  xsetlocale (LC_ALL, "de_DE.ISO-8859-1");
 
   inmem = (char *) expr;
   inlen = strlen (expr);