diff --git a/iconv/Makefile b/iconv/Makefile
index a0d90cfeac..6e926f53e3 100644
--- a/iconv/Makefile
+++ b/iconv/Makefile
@@ -25,7 +25,7 @@ include ../Makeconfig
 headers		= iconv.h gconv.h
 routines	= iconv_open iconv iconv_close \
 		  gconv_open gconv gconv_close gconv_db gconv_conf \
-		  gconv_builtin gconv_simple gconv_trans gconv_cache
+		  gconv_builtin gconv_simple gconv_posix gconv_trans gconv_cache
 routines	+= gconv_dl gconv_charset
 
 vpath %.c ../locale/programs ../intl
diff --git a/iconv/gconv_builtin.h b/iconv/gconv_builtin.h
index 68c2369b1f..cd1805b3ce 100644
--- a/iconv/gconv_builtin.h
+++ b/iconv/gconv_builtin.h
@@ -89,6 +89,14 @@ BUILTIN_TRANSFORMATION ("INTERNAL", "ANSI_X3.4-1968//", 1, "=INTERNAL->ascii",
 			__gconv_transform_internal_ascii, NULL, 4, 4, 1, 1)
 
 
+BUILTIN_TRANSFORMATION ("POSIX//", "INTERNAL", 1, "=posix->INTERNAL",
+			__gconv_transform_posix_internal, __gconv_btwoc_posix,
+			1, 1, 4, 4)
+
+BUILTIN_TRANSFORMATION ("INTERNAL", "POSIX//", 1, "=INTERNAL->posix",
+			__gconv_transform_internal_posix, NULL, 4, 4, 1, 1)
+
+
 #if BYTE_ORDER == BIG_ENDIAN
 BUILTIN_ALIAS ("UNICODEBIG//", "ISO-10646/UCS2/")
 BUILTIN_ALIAS ("UCS-2BE//", "ISO-10646/UCS2/")
diff --git a/iconv/gconv_int.h b/iconv/gconv_int.h
index 1c6745043e..45ab1edfad 100644
--- a/iconv/gconv_int.h
+++ b/iconv/gconv_int.h
@@ -281,6 +281,8 @@ extern int __gconv_compare_alias (const char *name1, const char *name2)
 
 __BUILTIN_TRANSFORM (__gconv_transform_ascii_internal);
 __BUILTIN_TRANSFORM (__gconv_transform_internal_ascii);
+__BUILTIN_TRANSFORM (__gconv_transform_posix_internal);
+__BUILTIN_TRANSFORM (__gconv_transform_internal_posix);
 __BUILTIN_TRANSFORM (__gconv_transform_utf8_internal);
 __BUILTIN_TRANSFORM (__gconv_transform_internal_utf8);
 __BUILTIN_TRANSFORM (__gconv_transform_ucs2_internal);
@@ -299,6 +301,11 @@ __BUILTIN_TRANSFORM (__gconv_transform_utf16_internal);
    only ASCII characters.  */
 extern wint_t __gconv_btwoc_ascii (struct __gconv_step *step, unsigned char c);
 
+/* Specialized conversion function for a single byte to INTERNAL,
+   identity-mapping bytes [0, 0x7F], and moving [0x80, 0xFF] into the end
+   of the Low Surrogate Area at [U+DF80, U+DFFF].  */
+extern wint_t __gconv_btwoc_posix (struct __gconv_step *step, unsigned char c);
+
 #endif
 
 __END_DECLS
diff --git a/iconv/gconv_posix.c b/iconv/gconv_posix.c
new file mode 100644
index 0000000000..dcb13fbb43
--- /dev/null
+++ b/iconv/gconv_posix.c
@@ -0,0 +1,96 @@
+/* Simple transformations functions.
+   Copyright (C) 2022 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 <gconv_int.h>
+
+
+/* Specialized conversion function for a single byte to INTERNAL,
+   identity-mapping bytes [0, 0x7F], and moving [0x80, 0xFF] into the end
+   of the Low Surrogate Area at [U+DF80, U+DFFF].  */
+wint_t
+__gconv_btwoc_posix (struct __gconv_step *step, unsigned char c)
+{
+  if (c < 0x80)
+    return c;
+  else
+    return 0xdf00 + c;
+}
+
+
+/* Convert from {[0, 0x7F] => ISO 646-IRV; [0x80, 0xFF] => [U+DF80, U+DFFF]}
+   to the internal (UCS4-like) format.  */
+#define DEFINE_INIT		0
+#define DEFINE_FINI		0
+#define MIN_NEEDED_FROM		1
+#define MIN_NEEDED_TO		4
+#define FROM_DIRECTION		1
+#define FROM_LOOP		posix_internal_loop
+#define TO_LOOP			posix_internal_loop /* This is not used.  */
+#define FUNCTION_NAME		__gconv_transform_posix_internal
+#define ONE_DIRECTION		1
+
+#define MIN_NEEDED_INPUT	MIN_NEEDED_FROM
+#define MIN_NEEDED_OUTPUT	MIN_NEEDED_TO
+#define LOOPFCT			FROM_LOOP
+#define BODY \
+  {									      \
+    if (__glibc_unlikely (*inptr > '\x7f'))				      \
+      *((uint32_t *) outptr) = 0xdf00 + *inptr++;			      \
+    else								      \
+      *((uint32_t *) outptr) = *inptr++;				      \
+    outptr += sizeof (uint32_t);					      \
+  }
+#include <iconv/loop.c>
+#include <iconv/skeleton.c>
+
+
+/* Convert from the internal (UCS4-like) format to
+   {ISO 646-IRV => [0, 0x7F]; [U+DF80, U+DFFF] => [0x80, 0xFF]}.  */
+#define DEFINE_INIT		0
+#define DEFINE_FINI		0
+#define MIN_NEEDED_FROM		4
+#define MIN_NEEDED_TO		1
+#define FROM_DIRECTION		1
+#define FROM_LOOP		internal_posix_loop
+#define TO_LOOP			internal_posix_loop /* This is not used.  */
+#define FUNCTION_NAME		__gconv_transform_internal_posix
+#define ONE_DIRECTION		1
+
+#define MIN_NEEDED_INPUT	MIN_NEEDED_FROM
+#define MIN_NEEDED_OUTPUT	MIN_NEEDED_TO
+#define LOOPFCT			FROM_LOOP
+#define BODY \
+  {									      \
+    uint32_t val = *((const uint32_t *) inptr);				      \
+    if (__glibc_unlikely ((val > 0x7f && val < 0xdf80) || val > 0xdfff))      \
+      {									      \
+	UNICODE_TAG_HANDLER (val, 4);					      \
+	STANDARD_TO_LOOP_ERR_HANDLER (4);				      \
+      }									      \
+    else								      \
+      {									      \
+	if (__glibc_unlikely (val > 0x7f))				      \
+	  val -= 0xdf00;						      \
+	*outptr++ = val;						      \
+	inptr += sizeof (uint32_t);					      \
+      }									      \
+  }
+#define LOOP_NEED_FLAGS
+#include <iconv/loop.c>
+#include <iconv/skeleton.c>
diff --git a/iconv/tst-iconv_prog.sh b/iconv/tst-iconv_prog.sh
index b3d8bf5110..a24d8d2207 100644
--- a/iconv/tst-iconv_prog.sh
+++ b/iconv/tst-iconv_prog.sh
@@ -285,3 +285,46 @@ for errorcommand in "${errorarray[@]}"; do
   execute_test
   check_errtest_result
 done
+
+allbytes ()
+{
+  for (( i = 0; i <= 255; i++ )); do
+    printf '\'"$(printf "%o" "$i")"
+  done
+}
+
+allucs4be ()
+{
+  for (( i = 0; i <= 127; i++ )); do
+    printf '\0\0\0\'"$(printf "%o" "$i")"
+  done
+  for (( i = 128; i <= 255; i++ )); do
+    printf '\0\0\xdf\'"$(printf "%o" "$i")"
+  done
+}
+
+check_posix_result ()
+{
+  if [ $? -eq 0 ]; then
+    result=PASS
+  else
+    result=FAIL
+  fi
+
+  echo "$result: from \"$1\", to: \"$2\""
+
+  if [ "$result" != "PASS" ]; then
+    exit 1
+  fi
+}
+
+check_posix_encoding ()
+{
+  eval PROG=\"$ICONV\"
+  allbytes  | $PROG -f POSIX -t UCS-4BE | cmp -s - <(allucs4be)
+  check_posix_result POSIX UCS-4BE
+  allucs4be | $PROG -f UCS-4BE -t POSIX | cmp -s - <(allbytes)
+  check_posix_result UCS-4BE POSIX
+}
+
+check_posix_encoding
diff --git a/iconvdata/tst-tables.sh b/iconvdata/tst-tables.sh
index 4207b44175..33a02158ac 100755
--- a/iconvdata/tst-tables.sh
+++ b/iconvdata/tst-tables.sh
@@ -31,6 +31,7 @@ cat <<EOF |
   # Keep this list in the same order as gconv-modules.
   #
   # charset name    table name          comment
+  POSIX
   ASCII             ANSI_X3.4-1968
   ISO646-GB         BS_4730
   ISO646-CA         CSA_Z243.4-1985-1
diff --git a/inet/tst-idna_name_classify.c b/inet/tst-idna_name_classify.c
index bfd34eee31..b379481844 100644
--- a/inet/tst-idna_name_classify.c
+++ b/inet/tst-idna_name_classify.c
@@ -37,11 +37,11 @@ do_test (void)
   puts ("info: C locale tests");
   locale_insensitive_tests ();
   TEST_COMPARE (__idna_name_classify ("abc\200def"),
-                idna_name_encoding_error);
+                idna_name_nonascii);
   TEST_COMPARE (__idna_name_classify ("abc\200\\def"),
-                idna_name_encoding_error);
+                idna_name_nonascii_backslash);
   TEST_COMPARE (__idna_name_classify ("abc\377def"),
-                idna_name_encoding_error);
+                idna_name_nonascii);
 
   puts ("info: en_US.ISO-8859-1 locale tests");
   if (setlocale (LC_CTYPE, "en_US.ISO-8859-1") == 0)
diff --git a/locale/tst-C-locale.c b/locale/tst-C-locale.c
index 6bd0367069..f30396ae12 100644
--- a/locale/tst-C-locale.c
+++ b/locale/tst-C-locale.c
@@ -229,6 +229,75 @@ run_test (const char *locname)
   STRTEST (YESSTR, "");
   STRTEST (NOSTR, "");
 
+#define CONVTEST(b, v) \
+  {									      \
+    unsigned char bs[] = {b, 0};					      \
+    mbstate_t ctx = {};							      \
+    wchar_t wc = -1;							      \
+    size_t sz = mbrtowc(&wc, (char *) bs, 1, &ctx);			      \
+    if (sz != !!b)							      \
+      {									      \
+	printf ("mbrtowc(%02hhx) width in locale %s wrong "		      \
+		"(is %zd, should be %d)\n", *bs, locname, sz, !!b);	      \
+	result = 1;							      \
+      }									      \
+    if (wc != v)							      \
+      {									      \
+	printf ("mbrtowc(%02hhx) value in locale %s wrong "		      \
+		"(is %x, should be %x)\n", *bs, locname, wc, v);	      \
+	result = 1;							      \
+      }									      \
+  }
+  for(int i = 0; i <= 0x7f; ++i)
+    CONVTEST(i, i);
+  for(int i = 0x80; i <= 0xff; ++i)
+    CONVTEST(i, 0xdf00 + i);
+
+#define DECONVTEST(v, b) \
+  {									      \
+    unsigned char ob = -1;						      \
+    mbstate_t ctx = {};							      \
+    size_t sz = wcrtomb((char *) &ob, v, &ctx);				      \
+    if (sz != 1)							      \
+      {									      \
+	printf ("wcrtomb(%x) width in locale %s wrong "			      \
+		"(is %zd, should be 1)\n", v, locname, sz);		      \
+	result = 1;							      \
+      }									      \
+    if (ob != b)							      \
+      {									      \
+	printf ("wcrtomb(%x) value in locale %s wrong "			      \
+		"(is %hhx, should be %hhx)\n", v, locname, ob, b);	      \
+	result = 1;							      \
+      }									      \
+  }
+#define DECONVERR(v) \
+  {									      \
+    unsigned char ob = -1;						      \
+    mbstate_t ctx = {};							      \
+    size_t sz = wcrtomb((char *) &ob, v, &ctx);				      \
+    if (sz != (size_t) -1)						      \
+      {									      \
+	printf ("wcrtomb(%x) width in locale %s wrong "			      \
+		"(is %zd, should be (size_t )-1)\n", v, locname, sz);	      \
+	result = 1;							      \
+      }									      \
+    if (ob != (unsigned char) -1)					      \
+      {									      \
+	printf ("wcrtomb(%x) value in locale %s wrong "			      \
+		"(is %hhx, should be unchanged)\n", v, locname, ob);	      \
+	result = 1;							      \
+      }									      \
+  }
+  for(int i = 0; i <= 0x7f; ++i)
+    DECONVTEST(i, i);
+  for(int i = 0x80; i < 0xdf00; ++i)
+    DECONVERR(i);
+  for(int i = 0x80; i <= 0xff; ++i)
+    DECONVTEST(0xdf00 + i, i);
+  for(int i = 0xe000; i <= 0xffff; ++i)
+    DECONVERR(i);
+
   /* Test the new locale mechanisms.  */
   loc = newlocale (LC_ALL_MASK, locname, NULL);
   if (loc == NULL)
diff --git a/localedata/charmaps/POSIX b/localedata/charmaps/POSIX
new file mode 100644
index 0000000000..c44007ff49
--- /dev/null
+++ b/localedata/charmaps/POSIX
@@ -0,0 +1,136 @@
+<code_set_name> POSIX
+<comment_char> %
+<escape_char> /
+% source: cf. localedata/locales/POSIX, LC_COLLATE
+
+CHARMAP
+<U0000>     /x00         NULL (NUL)
+<U0001>     /x01         START OF HEADING (SOH)
+<U0002>     /x02         START OF TEXT (STX)
+<U0003>     /x03         END OF TEXT (ETX)
+<U0004>     /x04         END OF TRANSMISSION (EOT)
+<U0005>     /x05         ENQUIRY (ENQ)
+<U0006>     /x06         ACKNOWLEDGE (ACK)
+<U0007>     /x07         BELL (BEL)
+<U0008>     /x08         BACKSPACE (BS)
+<U0009>     /x09         CHARACTER TABULATION (HT)
+<U000A>     /x0a         LINE FEED (LF)
+<U000B>     /x0b         LINE TABULATION (VT)
+<U000C>     /x0c         FORM FEED (FF)
+<U000D>     /x0d         CARRIAGE RETURN (CR)
+<U000E>     /x0e         SHIFT OUT (SO)
+<U000F>     /x0f         SHIFT IN (SI)
+<U0010>     /x10         DATALINK ESCAPE (DLE)
+<U0011>     /x11         DEVICE CONTROL ONE (DC1)
+<U0012>     /x12         DEVICE CONTROL TWO (DC2)
+<U0013>     /x13         DEVICE CONTROL THREE (DC3)
+<U0014>     /x14         DEVICE CONTROL FOUR (DC4)
+<U0015>     /x15         NEGATIVE ACKNOWLEDGE (NAK)
+<U0016>     /x16         SYNCHRONOUS IDLE (SYN)
+<U0017>     /x17         END OF TRANSMISSION BLOCK (ETB)
+<U0018>     /x18         CANCEL (CAN)
+<U0019>     /x19         END OF MEDIUM (EM)
+<U001A>     /x1a         SUBSTITUTE (SUB)
+<U001B>     /x1b         ESCAPE (ESC)
+<U001C>     /x1c         FILE SEPARATOR (IS4)
+<U001D>     /x1d         GROUP SEPARATOR (IS3)
+<U001E>     /x1e         RECORD SEPARATOR (IS2)
+<U001F>     /x1f         UNIT SEPARATOR (IS1)
+<U0020>     /x20         SPACE
+<U0021>     /x21         EXCLAMATION MARK
+<U0022>     /x22         QUOTATION MARK
+<U0023>     /x23         NUMBER SIGN
+<U0024>     /x24         DOLLAR SIGN
+<U0025>     /x25         PERCENT SIGN
+<U0026>     /x26         AMPERSAND
+<U0027>     /x27         APOSTROPHE
+<U0028>     /x28         LEFT PARENTHESIS
+<U0029>     /x29         RIGHT PARENTHESIS
+<U002A>     /x2a         ASTERISK
+<U002B>     /x2b         PLUS SIGN
+<U002C>     /x2c         COMMA
+<U002D>     /x2d         HYPHEN-MINUS
+<U002E>     /x2e         FULL STOP
+<U002F>     /x2f         SOLIDUS
+<U0030>     /x30         DIGIT ZERO
+<U0031>     /x31         DIGIT ONE
+<U0032>     /x32         DIGIT TWO
+<U0033>     /x33         DIGIT THREE
+<U0034>     /x34         DIGIT FOUR
+<U0035>     /x35         DIGIT FIVE
+<U0036>     /x36         DIGIT SIX
+<U0037>     /x37         DIGIT SEVEN
+<U0038>     /x38         DIGIT EIGHT
+<U0039>     /x39         DIGIT NINE
+<U003A>     /x3a         COLON
+<U003B>     /x3b         SEMICOLON
+<U003C>     /x3c         LESS-THAN SIGN
+<U003D>     /x3d         EQUALS SIGN
+<U003E>     /x3e         GREATER-THAN SIGN
+<U003F>     /x3f         QUESTION MARK
+<U0040>     /x40         COMMERCIAL AT
+<U0041>     /x41         LATIN CAPITAL LETTER A
+<U0042>     /x42         LATIN CAPITAL LETTER B
+<U0043>     /x43         LATIN CAPITAL LETTER C
+<U0044>     /x44         LATIN CAPITAL LETTER D
+<U0045>     /x45         LATIN CAPITAL LETTER E
+<U0046>     /x46         LATIN CAPITAL LETTER F
+<U0047>     /x47         LATIN CAPITAL LETTER G
+<U0048>     /x48         LATIN CAPITAL LETTER H
+<U0049>     /x49         LATIN CAPITAL LETTER I
+<U004A>     /x4a         LATIN CAPITAL LETTER J
+<U004B>     /x4b         LATIN CAPITAL LETTER K
+<U004C>     /x4c         LATIN CAPITAL LETTER L
+<U004D>     /x4d         LATIN CAPITAL LETTER M
+<U004E>     /x4e         LATIN CAPITAL LETTER N
+<U004F>     /x4f         LATIN CAPITAL LETTER O
+<U0050>     /x50         LATIN CAPITAL LETTER P
+<U0051>     /x51         LATIN CAPITAL LETTER Q
+<U0052>     /x52         LATIN CAPITAL LETTER R
+<U0053>     /x53         LATIN CAPITAL LETTER S
+<U0054>     /x54         LATIN CAPITAL LETTER T
+<U0055>     /x55         LATIN CAPITAL LETTER U
+<U0056>     /x56         LATIN CAPITAL LETTER V
+<U0057>     /x57         LATIN CAPITAL LETTER W
+<U0058>     /x58         LATIN CAPITAL LETTER X
+<U0059>     /x59         LATIN CAPITAL LETTER Y
+<U005A>     /x5a         LATIN CAPITAL LETTER Z
+<U005B>     /x5b         LEFT SQUARE BRACKET
+<U005C>     /x5c         REVERSE SOLIDUS
+<U005D>     /x5d         RIGHT SQUARE BRACKET
+<U005E>     /x5e         CIRCUMFLEX ACCENT
+<U005F>     /x5f         LOW LINE
+<U0060>     /x60         GRAVE ACCENT
+<U0061>     /x61         LATIN SMALL LETTER A
+<U0062>     /x62         LATIN SMALL LETTER B
+<U0063>     /x63         LATIN SMALL LETTER C
+<U0064>     /x64         LATIN SMALL LETTER D
+<U0065>     /x65         LATIN SMALL LETTER E
+<U0066>     /x66         LATIN SMALL LETTER F
+<U0067>     /x67         LATIN SMALL LETTER G
+<U0068>     /x68         LATIN SMALL LETTER H
+<U0069>     /x69         LATIN SMALL LETTER I
+<U006A>     /x6a         LATIN SMALL LETTER J
+<U006B>     /x6b         LATIN SMALL LETTER K
+<U006C>     /x6c         LATIN SMALL LETTER L
+<U006D>     /x6d         LATIN SMALL LETTER M
+<U006E>     /x6e         LATIN SMALL LETTER N
+<U006F>     /x6f         LATIN SMALL LETTER O
+<U0070>     /x70         LATIN SMALL LETTER P
+<U0071>     /x71         LATIN SMALL LETTER Q
+<U0072>     /x72         LATIN SMALL LETTER R
+<U0073>     /x73         LATIN SMALL LETTER S
+<U0074>     /x74         LATIN SMALL LETTER T
+<U0075>     /x75         LATIN SMALL LETTER U
+<U0076>     /x76         LATIN SMALL LETTER V
+<U0077>     /x77         LATIN SMALL LETTER W
+<U0078>     /x78         LATIN SMALL LETTER X
+<U0079>     /x79         LATIN SMALL LETTER Y
+<U007A>     /x7a         LATIN SMALL LETTER Z
+<U007B>     /x7b         LEFT CURLY BRACKET
+<U007C>     /x7c         VERTICAL LINE
+<U007D>     /x7d         RIGHT CURLY BRACKET
+<U007E>     /x7e         TILDE
+<U007F>     /x7f         DELETE (DEL)
+<UDF80>..<UDFFF> /x80
+END CHARMAP
diff --git a/localedata/locales/POSIX b/localedata/locales/POSIX
index 7ec7f1c577..fc34a6abc1 100644
--- a/localedata/locales/POSIX
+++ b/localedata/locales/POSIX
@@ -97,6 +97,20 @@ END LC_CTYPE
 LC_COLLATE
 % This is the POSIX Locale definition for the LC_COLLATE category.
 % The order is the same as in the ASCII code set.
+% Values above <DEL> (<U007F>) inserted in order, per Issue 7 TC2,
+% XBD, 7.3.2, LC_COLLATE Category in the POSIX Locale:
+% > All characters not explicitly listed here shall be inserted
+% > in the character collation order after the listed characters
+% > and shall be assigned unique primary weights. If the listed
+% > characters have ASCII encoding, the other characters shall
+% > be in ascending order according to their coded character set values
+% Since Issue 7 TC2 (XBD, 6.2 Character Encoding):
+% > The POSIX locale shall contain 256 single-byte characters [...]
+% (cf. bug 663, 674).
+% this is in contrast to previous issues, which limited the POSIX
+% locale to the Portable Character Set (7-bit ASCII).
+% We use the end of the Low Surrogate Area to contain these,
+% yielding [<UDF80>, <UDFFF>]
 order_start forward
 <U0000>
 <U0001>
@@ -226,7 +240,134 @@ order_start forward
 <U007D>
 <U007E>
 <U007F>
-UNDEFINED
+<UDF80>
+<UDF81>
+<UDF82>
+<UDF83>
+<UDF84>
+<UDF85>
+<UDF86>
+<UDF87>
+<UDF88>
+<UDF89>
+<UDF8A>
+<UDF8B>
+<UDF8C>
+<UDF8D>
+<UDF8E>
+<UDF8F>
+<UDF90>
+<UDF91>
+<UDF92>
+<UDF93>
+<UDF94>
+<UDF95>
+<UDF96>
+<UDF97>
+<UDF98>
+<UDF99>
+<UDF9A>
+<UDF9B>
+<UDF9C>
+<UDF9D>
+<UDF9E>
+<UDF9F>
+<UDFA0>
+<UDFA1>
+<UDFA2>
+<UDFA3>
+<UDFA4>
+<UDFA5>
+<UDFA6>
+<UDFA7>
+<UDFA8>
+<UDFA9>
+<UDFAA>
+<UDFAB>
+<UDFAC>
+<UDFAD>
+<UDFAE>
+<UDFAF>
+<UDFB0>
+<UDFB1>
+<UDFB2>
+<UDFB3>
+<UDFB4>
+<UDFB5>
+<UDFB6>
+<UDFB7>
+<UDFB8>
+<UDFB9>
+<UDFBA>
+<UDFBB>
+<UDFBC>
+<UDFBD>
+<UDFBE>
+<UDFBF>
+<UDFC0>
+<UDFC1>
+<UDFC2>
+<UDFC3>
+<UDFC4>
+<UDFC5>
+<UDFC6>
+<UDFC7>
+<UDFC8>
+<UDFC9>
+<UDFCA>
+<UDFCB>
+<UDFCC>
+<UDFCD>
+<UDFCE>
+<UDFCF>
+<UDFD0>
+<UDFD1>
+<UDFD2>
+<UDFD3>
+<UDFD4>
+<UDFD5>
+<UDFD6>
+<UDFD7>
+<UDFD8>
+<UDFD9>
+<UDFDA>
+<UDFDB>
+<UDFDC>
+<UDFDD>
+<UDFDE>
+<UDFDF>
+<UDFE0>
+<UDFE1>
+<UDFE2>
+<UDFE3>
+<UDFE4>
+<UDFE5>
+<UDFE6>
+<UDFE7>
+<UDFE8>
+<UDFE9>
+<UDFEA>
+<UDFEB>
+<UDFEC>
+<UDFED>
+<UDFEE>
+<UDFEF>
+<UDFF0>
+<UDFF1>
+<UDFF2>
+<UDFF3>
+<UDFF4>
+<UDFF5>
+<UDFF6>
+<UDFF7>
+<UDFF8>
+<UDFF9>
+<UDFFA>
+<UDFFB>
+<UDFFC>
+<UDFFD>
+<UDFFE>
+<UDFFF>
 order_end
 %
 END LC_COLLATE
diff --git a/stdio-common/tst-printf-bz25691.c b/stdio-common/tst-printf-bz25691.c
index 44844e71c3..e66242b58f 100644
--- a/stdio-common/tst-printf-bz25691.c
+++ b/stdio-common/tst-printf-bz25691.c
@@ -30,6 +30,8 @@
 static int
 do_test (void)
 {
+  setlocale(LC_CTYPE, "C.UTF-8");
+
   mtrace ();
 
   /* For 's' conversion specifier with 'l' modifier the array must be
diff --git a/wcsmbs/wcsmbsload.c b/wcsmbs/wcsmbsload.c
index 0f0f55f9ed..97de9afd25 100644
--- a/wcsmbs/wcsmbsload.c
+++ b/wcsmbs/wcsmbsload.c
@@ -33,10 +33,10 @@ static const struct __gconv_step to_wc =
   .__shlib_handle = NULL,
   .__modname = NULL,
   .__counter = INT_MAX,
-  .__from_name = (char *) "ANSI_X3.4-1968//TRANSLIT",
+  .__from_name = (char *) "POSIX",
   .__to_name = (char *) "INTERNAL",
-  .__fct = __gconv_transform_ascii_internal,
-  .__btowc_fct = __gconv_btwoc_ascii,
+  .__fct = __gconv_transform_posix_internal,
+  .__btowc_fct = __gconv_btwoc_posix,
   .__init_fct = NULL,
   .__end_fct = NULL,
   .__min_needed_from = 1,
@@ -53,8 +53,8 @@ static const struct __gconv_step to_mb =
   .__modname = NULL,
   .__counter = INT_MAX,
   .__from_name = (char *) "INTERNAL",
-  .__to_name = (char *) "ANSI_X3.4-1968//TRANSLIT",
-  .__fct = __gconv_transform_internal_ascii,
+  .__to_name = (char *) "POSIX",
+  .__fct = __gconv_transform_internal_posix,
   .__btowc_fct = NULL,
   .__init_fct = NULL,
   .__end_fct = NULL,
@@ -67,7 +67,9 @@ static const struct __gconv_step to_mb =
 };
 
 
-/* For the default locale we only have to handle ANSI_X3.4-1968.  */
+/* The default/"POSIX"/"C" locale is an 8-bit-clean mapping
+   with ANSI_X3.4-1968 in the first 128 characters;
+   we lift the remaining bytes by <UDF00>.  */
 const struct gconv_fcts __wcsmbs_gconv_fcts_c =
 {
   .towc = (struct __gconv_step *) &to_wc,
