Update from Gnulib by running admin/merge-gnulib

In addition to the automatic changes, also do the following, needed due to recent Gnulib changes. * admin/merge-gnulib (AVOIDED_MODULES): Add btoc32, c32_apply_type_test, c32_get_type_test, c32isalnum, c32rtomb, c32tolower, c32toupper, localeinfo, mbrtoc32-regular. Remove btowc, iswctype, mbrtowc, wcrtomb, wctype, wctype-h. Also remove iswblank, iswdigit, iswxdigit, locale-h, raise, stdarg-h, some of which perhaps could have been removed earlier. * configure.ac (_REGEX_AVOID_UCHAR_H): New macro.
2026-06-14 04:21:24 +00:00 · 2026-05-26 17:51:44 -07:00 · 2026-05-26 17:51:44 -07:00 · 834ff524f9
commit 834ff524f9
parent 6fb6a4f76d
66 changed files with 3317 additions and 1173 deletions
--- a/admin/merge-gnulib
+++ b/admin/merge-gnulib
@ -58,14 +58,18 @@ GNULIB_MODULES='
 '

 AVOIDED_MODULES='
-  access btowc chmod close crypto/af_alg dup fchdir fstat gnulib-i18n
-  iswblank iswctype iswdigit iswxdigit langinfo-h libgmp-mpq
-  localcharset locale-h localename-unsafe-limited lock
-  mbrtowc mbsinit memchr mkdir msvc-inval msvc-nothrow nl_langinfo
-  openat-die opendir pthread-h raise
-  save-cwd select setenv sigprocmask stat std-gnu11 stdarg-h strncpy
+  access btoc32
+  c32_apply_type_test c32_get_type_test
+  c32isalnum c32rtomb c32tolower c32toupper
+  chmod close crypto/af_alg dup fchdir fstat gnulib-i18n
+  langinfo-h libgmp-mpq
+  localcharset localeinfo localename-unsafe-limited lock
+  mbrtoc32-regular mbsinit memchr mkdir
+  msvc-inval msvc-nothrow nl_langinfo
+  openat-die opendir pthread-h
+  save-cwd select setenv sigprocmask stat std-gnu11 strncpy
  threadlib tzset unsetenv utime utime-h
-  wchar-h wcrtomb wctype wctype-h
+  wchar-h uchar-h
 '

 GNULIB_TOOL_FLAGS='
--- a/build-aux/config.guess
+++ b/build-aux/config.guess
@ -1,10 +1,10 @@
 #! /bin/sh
 # Attempt to guess a canonical system name.
-#   Copyright 1992-2025 Free Software Foundation, Inc.
+#   Copyright 1992-2026 Free Software Foundation, Inc.

 # shellcheck disable=SC2006,SC2268 # see below for rationale

-timestamp='2025-07-10'
+timestamp='2026-05-17'

 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@ -60,7 +60,7 @@ version="\
 GNU config.guess ($timestamp)

 Originally written by Per Bothner.
-Copyright 1992-2025 Free Software Foundation, Inc.
+Copyright 1992-2026 Free Software Foundation, Inc.

 This is free software; see the source for copying conditions.  There is NO
 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE."
@ -150,7 +150,7 @@ UNAME_SYSTEM=`(uname -s) 2>/dev/null` || UNAME_SYSTEM=unknown
 UNAME_VERSION=`(uname -v) 2>/dev/null` || UNAME_VERSION=unknown

 case $UNAME_SYSTEM in
-Linux|GNU|GNU/*)
+Ironclad|Linux|GNU|GNU/*)
 	LIBC=unknown

 	set_cc_for_build
@ -167,6 +167,8 @@ Linux|GNU|GNU/*)
 	LIBC=gnu
 	#elif defined(__LLVM_LIBC__)
 	LIBC=llvm
+	#elif defined(__mlibc__)
+	LIBC=mlibc
 	#else
 	#include <stdarg.h>
 	/* First heuristic to detect musl libc.  */
@ -1186,6 +1188,9 @@ EOF
    sparc:Linux:*:* | sparc64:Linux:*:*)
 	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
 	;;
+    sw_64:Linux:*:*)
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
    tile*:Linux:*:*)
 	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
 	;;
@ -1598,10 +1603,10 @@ EOF
 	GUESS=$UNAME_MACHINE-unknown-unleashed$UNAME_RELEASE
 	;;
    x86_64:[Ii]ronclad:*:*|i?86:[Ii]ronclad:*:*)
-	GUESS=$UNAME_MACHINE-pc-ironclad-mlibc
+	GUESS=$UNAME_MACHINE-pc-ironclad-$LIBC
 	;;
    *:[Ii]ronclad:*:*)
-	GUESS=$UNAME_MACHINE-unknown-ironclad-mlibc
+	GUESS=$UNAME_MACHINE-unknown-ironclad-$LIBC
 	;;
 esac

--- a/build-aux/config.sub
+++ b/build-aux/config.sub
@ -1,10 +1,10 @@
 #! /bin/sh
 # Configuration validation subroutine script.
-#   Copyright 1992-2025 Free Software Foundation, Inc.
+#   Copyright 1992-2026 Free Software Foundation, Inc.

 # shellcheck disable=SC2006,SC2268,SC2162 # see below for rationale

-timestamp='2025-07-10'
+timestamp='2026-05-17'

 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@ -76,7 +76,7 @@ Report bugs and patches to <config-patches@gnu.org>."
 version="\
 GNU config.sub ($timestamp)

-Copyright 1992-2025 Free Software Foundation, Inc.
+Copyright 1992-2026 Free Software Foundation, Inc.

 This is free software; see the source for copying conditions.  There is NO
 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE."
@ -1432,6 +1432,7 @@ case $cpu-$vendor in
 			| sparcv9v \
 			| spu \
 			| sv1 \
+			| sw_64 \
 			| sx* \
 			| tahoe \
 			| thumbv7* \
@ -1525,7 +1526,7 @@ EOF
 		;;
 	ironclad*)
 		kernel=ironclad
-		os=`echo "$basic_os" | sed -e 's|ironclad|mlibc|'`
+		os=`echo "$basic_os" | sed -e 's|ironclad|gnu|'`
 		;;
 	linux*)
 		kernel=linux
@ -2220,7 +2221,7 @@ case $kernel-$os-$obj in
 		;;
 	uclinux-uclibc*- | uclinux-gnu*- )
 		;;
-	ironclad-mlibc*-)
+	ironclad-gnu*- | ironclad-mlibc*- )
 		;;
 	managarm-mlibc*- | managarm-kernel*- )
 		;;
--- a/configure.ac
+++ b/configure.ac
@ -1615,6 +1615,10 @@ AC_DEFUN([gt_TYPE_WINT_T],
 AC_DEFUN([gl_TYPE_OFF64_T],
  [HAVE_OFF64_T=1
   AC_SUBST([HAVE_OFF64_T])])
+# Emacs does not want Gnulib's fixes for glibc bug 20381 or for
+# Unicode-compatible case matching, as that brings in too many Gnulib files.
+AC_DEFINE([_REGEX_AVOID_UCHAR_H], [1],
+  [Define to 1 so that the Gnulib regex module does not use Gnulib uchar-h.])

 # Initialize gnulib right after choosing the compiler.
 dnl Amongst other things, this sets AR and ARFLAGS.
--- a/doc/misc/texinfo.tex
+++ b/doc/misc/texinfo.tex
@ -3,7 +3,7 @@
 % Load plain if necessary, i.e., if running under initex.
 \expandafter\ifx\csname fmtname\endcsname\relax\input plain\fi
 %
-\def\texinfoversion{2025-12-23.13}
+\def\texinfoversion{2026-04-26.12}
 %
 % Copyright 1985, 1986, 1988, 1990-2025 Free Software Foundation, Inc.
 %
@ -348,7 +348,6 @@
    % before the \shipout runs.
    %
    \atdummies         % don't expand commands in the output.
-    \turnoffactive
    \shipout\vbox{%
      % Do this early so pdf references go to the beginning of the page.
      \ifpdfmakepagedest \pdfdest name{\the\pageno} xyz\fi
@ -5321,14 +5320,13 @@
 \def\indexisfl{fl}

 % Definition for writing index entry sort key.
-{
-\catcode`\-=13
-\gdef\indexwritesortas{%
+\def\indexwritesortas{%
  \begingroup
  \indexnonalnumreappear
-  \indexwritesortasxxx}
-\gdef\indexwritesortasxxx#1{%
-  \xdef\indexsortkey{#1}\endgroup}
+  \indexwritesortasxxx
+}
+\def\indexwritesortasxxx#1{%
+  \xdef\indexsortkey{#1}\endgroup
 }

 \def\indexwriteseealso#1{
@ -5359,6 +5357,51 @@
  \expandafter\doindexsegment#1\subentry\finish\subentry
 }

+% \checksortas\segment
+% Call \indexwritesortas if a @sortas command appears in the segment
+\def\checksortas#1{
+  \let\sortas\relax
+  \expandafter\checksortasx#1\relax\sortas{}\sortas
+}
+\def\checksortasx#1\sortas#2#3\sortas{%
+  \def\tmp{#3}%
+  \ifx\tmp\empty\else
+    \indexwritesortas{#2}%
+  \fi
+}
+
+% \checkseealso\segment
+% Call \indexwriteseealso if a @seealso command appears in the segment
+\def\checkseealso#1{
+  \let\seealso\relax
+  \expandafter\checkseealsox#1\relax\seealso{}\seealso
+}
+\def\checkseealsox#1\seealso#2#3\seealso{%
+  \def\tmp{#3}%
+  \ifx\tmp\empty\else
+    \indexwriteseealso{#2}%
+  \fi
+}
+
+% \checkseeentry\segment
+% Call \indexwriteseeentry if a @seeentry command appears in the segment
+\def\checkseeentry#1{
+  \let\seeentry\relax
+  \expandafter\checkseeentryx#1\relax\seeentry{}\seeentry
+}
+\def\checkseeentryx#1\seeentry#2#3\seeentry{%
+  \def\tmp{#3}%
+  \ifx\tmp\empty\else
+    \indexwriteseeentry{#2}%
+  \fi
+}
+
+\def\extractindexcommands#1{%
+  \checksortas#1%
+  \checkseealso#1%
+  \checkseeentry#1%
+}
+
 % append the results from the next segment
 \def\doindexsegment#1\subentry{%
  \def\segment{#1}%
@ -5378,9 +5421,6 @@
    % Get the string to sort by.  Process the segment with all
    % font commands turned off.
    \bgroup
-      \let\sortas\indexwritesortas
-      \let\seealso\indexwriteseealso
-      \let\seeentry\indexwriteseeentry
      \indexnofonts
      % The braces around the commands are recognized by texindex.
      \def\lbracechar{{\string\indexlbrace}}%
@ -5394,11 +5434,10 @@
      %
      \let\indexsortkey\empty
      \global\let\pagenumbertext\empty
-      % Execute the segment and throw away the typeset output.  This executes
-      % any @sortas or @seealso commands in this segment.
-      \setbox\dummybox = \hbox{\segment}%
+      \extractindexcommands\segment
      \ifx\indexsortkey\empty{%
        \indexnonalnumdisappear
+        \inindexsortkeytrue
        \xdef\trimmed{\segment}%
        \xdef\trimmed{\expandafter\eatspaces\expandafter{\trimmed}}%
        \xdef\indexsortkey{\trimmed}%
@ -5419,7 +5458,6 @@
  \fi
 }
 \def\isfinish{\finish}%
-\newbox\dummybox % used above

 \let\subentry\relax

@ -7007,6 +7045,7 @@
 \newdimen\curchapmax
 \newdimen\cursecmax
 \newdimen\curssecmax
+\newbox\dummybox % used above


 % set #1 to the maximum section width for #2
@ -10231,6 +10270,15 @@
  \global\righthyphenmin = #3\relax
 }

+% @documentlanguagevariant - do nothing
+\parseargdef\documentlanguagevariant{}
+
+% @documentscript - do nothing
+% This command would only become relevant if we had translations in
+% multiple "scripts", e.g. Sebian in both Latin and Cyrillic alphabets.
+% However, we do not even support loading Cyrillic fonts.
+\parseargdef\documentscript{}
+
 % XeTeX and LuaTeX can handle Unicode natively.
 % Their default I/O uses UTF-8 sequences instead of a byte-wise operation.
 % Other TeX engines' I/O (pdfTeX, etc.) is byte-wise.
@ -10673,6 +10721,38 @@
 \newif\ifutfviiidefinedwarning
 \utfviiidefinedwarningtrue

+% Macros to output a string to sort a multibyte UTF-8 sequence by.
+% Check if there is a special definition to be used in the index
+% sort key for a character.
+% Output the sequence as-is, surrounded by curly braces.  The braces are
+% to help texindex find the first character regardless of locale character
+% encoding or version of awk used to run texindex.
+\gdef\UTFviiiSortkeyTwo#1#2{%
+  \expandafter\ifx\csname sort:#1#2\endcsname\relax
+    {\string #1\string #2}%
+  \else
+    \csname sort:#1#2\endcsname
+  \fi
+}
+\gdef\UTFviiiSortkeyThree#1#2#3{%
+  \expandafter\ifx\csname sort:#1#2#3\endcsname\relax
+    {\string #1\string #2\string #3}%
+  \else
+    \csname sort:#1#2#3\endcsname
+  \fi
+}
+\gdef\UTFviiiSortkeyFour#1#2#3#4{%
+  \expandafter\ifx\csname sort:#1#2#3#4\endcsname\relax
+    {\string #1\string #2\string #3\string #4}%
+  \else
+    \csname sort:#1#2#3#4\endcsname
+  \fi
+}
+
+% We use this with the \ifindexsortkey condition to expand and discard
+% an \else block in the containing conditional.
+\def\swapnestedfi#1\fi{\fi\expandafter#1\expandafter}
+
 % Give non-ASCII bytes the active definitions for processing UTF-8 sequences
 \begingroup
  \catcode`\~13
@ -10691,8 +10771,8 @@
      \expandafter\UTFviiiLoop
    \fi}
  %
-  % For bytes other than the first in a UTF-8 sequence.  Not expected to
-  % be expanded except when writing to auxiliary files.
+  % UTF-8 continuation bytes (10XX XXXX) or unused (hex C1, C2).
+  % Not expected to be expanded except when writing to auxiliary files.
  \countUTFx = "80
  \countUTFy = "C2
  \def\UTFviiiTmp{%
@ -10704,7 +10784,9 @@
  \countUTFy = "E0
  \def\UTFviiiTmp{%
    \gdef~{%
-        \ifpassthroughchars $%
+        \ifpassthroughchars
+          \ifinindexsortkey\swapnestedfi\UTFviiiSortkeyTwo\fi
+          $%
        \else\expandafter\UTFviiiTwoOctets\expandafter$\fi}}%
  \UTFviiiLoop

@ -10712,7 +10794,9 @@
  \countUTFy = "F0
  \def\UTFviiiTmp{%
    \gdef~{%
-        \ifpassthroughchars $%
+        \ifpassthroughchars
+          \ifinindexsortkey\swapnestedfi\UTFviiiSortkeyThree\fi
+          $%
        \else\expandafter\UTFviiiThreeOctets\expandafter$\fi}}%
  \UTFviiiLoop

@ -10720,7 +10804,9 @@
  \countUTFy = "F4
  \def\UTFviiiTmp{%
    \gdef~{%
-        \ifpassthroughchars $%
+        \ifpassthroughchars
+          \ifinindexsortkey\swapnestedfi\UTFviiiSortkeyFour\fi
+          $%
        \else\expandafter\UTFviiiFourOctets\expandafter$\fi
        }}%
  \UTFviiiLoop
@ -10814,7 +10900,7 @@
      \parseXMLCharref
      %
      % Completely expand \UTFviiiTmp, which looks like:
-      % 1.  \UTFviiTwoOctetsName B1 B2
+      % 1.  \UTFviiiTwoOctetsName B1 B2
      % 2.  \csname u8:B1 \string B2 \endcsname
      % 3.  \u8: B1 B2  (a single control sequence token)
      \xdef\UTFviiiTmp{\UTFviiiTmp}%
@ -10891,6 +10977,55 @@
    \uppercase{\gdef\UTFviiiTmp{#2#3#4}}}
 \endgroup

+% Used in \DefineSortKey as temporary definitions of \UTFviiiTwoOctetsName etc.
+% Use \expandafter\noexpand to prevent excessive expansion if \DefineSortKey is
+% called more than once for the same codepoint.
+\def\UTFviiiSortTwoOctetsName#1#2{%
+  \expandafter\noexpand\csname sort:#1\string #2\endcsname}%
+\def\UTFviiiSortThreeOctetsName#1#2#3{%
+  \expandafter\noexpand\csname sort:#1\string #2\string #3\endcsname}%
+\def\UTFviiiSortFourOctetsName#1#2#3#4{%
+  \expandafter\noexpand\csname sort:#1\string #2\string #3\string #4\endcsname}%
+
+% To be used in translation files to provide strings to be output
+% in the index sort key where a character occurs.
+\def\DefineSortKey#1#2{%
+  \countUTFz = "#1\relax
+  \parseXMLCharref
+  \def\tmp{#2}%
+  \expandafter\let\csname usort:#1\endcsname\tmp
+  \bgroup
+    \let\UTFviiiTwoOctetsName\UTFviiiSortTwoOctetsName
+    \let\UTFviiiThreeOctetsName\UTFviiiSortThreeOctetsName
+    \let\UTFviiiFourOctetsName\UTFviiiSortFourOctetsName
+    %
+    % Expand \UTFviiiTmp fully, which looks like:
+    % 1.  \UTFviiiTwoOctetsName B1 B2
+    % 2.  \expandafter\noexpand\csname sort:B1 \string B2 \endcsname
+    % 3.  \noexpand\sort: B1 B2
+    % 4.  \sort: B1 B2 (a single control sequence token)
+    %
+    \xdef\UTFviiiTmp{\UTFviiiTmp}%
+  \egroup
+  \expandafter\gdef\UTFviiiTmp{#2}%
+}
+
+% this could be used as follows
+%\DefineSortKey{00F1}{nzzz} % n tilde - sort between n and o
+%\DefineSortKey{00D1}{Nzzz} % N tilde - sort between n and o
+
+% Can be used in place of \DeclareUnicodeCharacter where the value for
+% the character is completely expandable when writing to indices:
+% Good: \DeclareUnicodeCharacterSK{00C9}{\'E}
+%         (\' expands to empty string)
+% Bad:  \DeclareUnicodeCharacterSK{03BB}{\ensuremath\lambda}%
+%         (\ensuremath expands to junk)
+\def\DeclareUnicodeCharacterSK#1#2{%
+  \DeclareUnicodeCharacter{#1}{#2}%
+  \DefineSortKey{#1}{#2}%
+}
+
+
 % For native Unicode handling (XeTeX and LuaTeX),
 % provide a definition macro that sets a catcode to `other' non-globally
 %
@ -11054,73 +11189,73 @@
  \DeclareUnicodeCharacter{00BE}{$3\over4$}%
  \DeclareUnicodeCharacter{00BF}{\questiondown}%
  %
-  \DeclareUnicodeCharacter{00C0}{\`A}%
-  \DeclareUnicodeCharacter{00C1}{\'A}%
-  \DeclareUnicodeCharacter{00C2}{\^A}%
-  \DeclareUnicodeCharacter{00C3}{\~A}%
-  \DeclareUnicodeCharacter{00C4}{\"A}%
-  \DeclareUnicodeCharacter{00C5}{\AA}%
-  \DeclareUnicodeCharacter{00C6}{\AE}%
-  \DeclareUnicodeCharacter{00C7}{\cedilla{C}}%
-  \DeclareUnicodeCharacter{00C8}{\`E}%
-  \DeclareUnicodeCharacter{00C9}{\'E}%
-  \DeclareUnicodeCharacter{00CA}{\^E}%
-  \DeclareUnicodeCharacter{00CB}{\"E}%
-  \DeclareUnicodeCharacter{00CC}{\`I}%
-  \DeclareUnicodeCharacter{00CD}{\'I}%
-  \DeclareUnicodeCharacter{00CE}{\^I}%
-  \DeclareUnicodeCharacter{00CF}{\"I}%
+  \DeclareUnicodeCharacterSK{00C0}{\`A}%
+  \DeclareUnicodeCharacterSK{00C1}{\'A}%
+  \DeclareUnicodeCharacterSK{00C2}{\^A}%
+  \DeclareUnicodeCharacterSK{00C3}{\~A}%
+  \DeclareUnicodeCharacterSK{00C4}{\"A}%
+  \DeclareUnicodeCharacterSK{00C5}{\AA}%
+  \DeclareUnicodeCharacterSK{00C6}{\AE}%
+  \DeclareUnicodeCharacterSK{00C7}{\cedilla{C}}%
+  \DeclareUnicodeCharacterSK{00C8}{\`E}%
+  \DeclareUnicodeCharacterSK{00C9}{\'E}%
+  \DeclareUnicodeCharacterSK{00CA}{\^E}%
+  \DeclareUnicodeCharacterSK{00CB}{\"E}%
+  \DeclareUnicodeCharacterSK{00CC}{\`I}%
+  \DeclareUnicodeCharacterSK{00CD}{\'I}%
+  \DeclareUnicodeCharacterSK{00CE}{\^I}%
+  \DeclareUnicodeCharacterSK{00CF}{\"I}%
  %
-  \DeclareUnicodeCharacter{00D0}{\DH}%
-  \DeclareUnicodeCharacter{00D1}{\~N}%
-  \DeclareUnicodeCharacter{00D2}{\`O}%
-  \DeclareUnicodeCharacter{00D3}{\'O}%
-  \DeclareUnicodeCharacter{00D4}{\^O}%
-  \DeclareUnicodeCharacter{00D5}{\~O}%
-  \DeclareUnicodeCharacter{00D6}{\"O}%
+  \DeclareUnicodeCharacterSK{00D0}{\DH}%
+  \DeclareUnicodeCharacterSK{00D1}{\~N}%
+  \DeclareUnicodeCharacterSK{00D2}{\`O}%
+  \DeclareUnicodeCharacterSK{00D3}{\'O}%
+  \DeclareUnicodeCharacterSK{00D4}{\^O}%
+  \DeclareUnicodeCharacterSK{00D5}{\~O}%
+  \DeclareUnicodeCharacterSK{00D6}{\"O}%
  \DeclareUnicodeCharacter{00D7}{\ensuremath\times}%
-  \DeclareUnicodeCharacter{00D8}{\O}%
-  \DeclareUnicodeCharacter{00D9}{\`U}%
-  \DeclareUnicodeCharacter{00DA}{\'U}%
-  \DeclareUnicodeCharacter{00DB}{\^U}%
-  \DeclareUnicodeCharacter{00DC}{\"U}%
-  \DeclareUnicodeCharacter{00DD}{\'Y}%
+  \DeclareUnicodeCharacterSK{00D8}{\O}%
+  \DeclareUnicodeCharacterSK{00D9}{\`U}%
+  \DeclareUnicodeCharacterSK{00DA}{\'U}%
+  \DeclareUnicodeCharacterSK{00DB}{\^U}%
+  \DeclareUnicodeCharacterSK{00DC}{\"U}%
+  \DeclareUnicodeCharacterSK{00DD}{\'Y}%
  \DeclareUnicodeCharacter{00DE}{\TH}%
-  \DeclareUnicodeCharacter{00DF}{\ss}%
+  \DeclareUnicodeCharacterSK{00DF}{\ss}%
  %
-  \DeclareUnicodeCharacter{00E0}{\`a}%
-  \DeclareUnicodeCharacter{00E1}{\'a}%
-  \DeclareUnicodeCharacter{00E2}{\^a}%
-  \DeclareUnicodeCharacter{00E3}{\~a}%
-  \DeclareUnicodeCharacter{00E4}{\"a}%
-  \DeclareUnicodeCharacter{00E5}{\aa}%
-  \DeclareUnicodeCharacter{00E6}{\ae}%
-  \DeclareUnicodeCharacter{00E7}{\cedilla{c}}%
-  \DeclareUnicodeCharacter{00E8}{\`e}%
-  \DeclareUnicodeCharacter{00E9}{\'e}%
-  \DeclareUnicodeCharacter{00EA}{\^e}%
-  \DeclareUnicodeCharacter{00EB}{\"e}%
-  \DeclareUnicodeCharacter{00EC}{\`{\dotless{i}}}%
-  \DeclareUnicodeCharacter{00ED}{\'{\dotless{i}}}%
-  \DeclareUnicodeCharacter{00EE}{\^{\dotless{i}}}%
-  \DeclareUnicodeCharacter{00EF}{\"{\dotless{i}}}%
+  \DeclareUnicodeCharacterSK{00E0}{\`a}%
+  \DeclareUnicodeCharacterSK{00E1}{\'a}%
+  \DeclareUnicodeCharacterSK{00E2}{\^a}%
+  \DeclareUnicodeCharacterSK{00E3}{\~a}%
+  \DeclareUnicodeCharacterSK{00E4}{\"a}%
+  \DeclareUnicodeCharacterSK{00E5}{\aa}%
+  \DeclareUnicodeCharacterSK{00E6}{\ae}%
+  \DeclareUnicodeCharacterSK{00E7}{\cedilla{c}}%
+  \DeclareUnicodeCharacterSK{00E8}{\`e}%
+  \DeclareUnicodeCharacterSK{00E9}{\'e}%
+  \DeclareUnicodeCharacterSK{00EA}{\^e}%
+  \DeclareUnicodeCharacterSK{00EB}{\"e}%
+  \DeclareUnicodeCharacterSK{00EC}{\`{\dotless{i}}}%
+  \DeclareUnicodeCharacterSK{00ED}{\'{\dotless{i}}}%
+  \DeclareUnicodeCharacterSK{00EE}{\^{\dotless{i}}}%
+  \DeclareUnicodeCharacterSK{00EF}{\"{\dotless{i}}}%
  %
-  \DeclareUnicodeCharacter{00F0}{\dh}%
-  \DeclareUnicodeCharacter{00F1}{\~n}%
-  \DeclareUnicodeCharacter{00F2}{\`o}%
-  \DeclareUnicodeCharacter{00F3}{\'o}%
-  \DeclareUnicodeCharacter{00F4}{\^o}%
-  \DeclareUnicodeCharacter{00F5}{\~o}%
-  \DeclareUnicodeCharacter{00F6}{\"o}%
+  \DeclareUnicodeCharacterSK{00F0}{\dh}%
+  \DeclareUnicodeCharacterSK{00F1}{\~n}%
+  \DeclareUnicodeCharacterSK{00F2}{\`o}%
+  \DeclareUnicodeCharacterSK{00F3}{\'o}%
+  \DeclareUnicodeCharacterSK{00F4}{\^o}%
+  \DeclareUnicodeCharacterSK{00F5}{\~o}%
+  \DeclareUnicodeCharacterSK{00F6}{\"o}%
  \DeclareUnicodeCharacter{00F7}{\ensuremath\div}%
-  \DeclareUnicodeCharacter{00F8}{\o}%
-  \DeclareUnicodeCharacter{00F9}{\`u}%
-  \DeclareUnicodeCharacter{00FA}{\'u}%
-  \DeclareUnicodeCharacter{00FB}{\^u}%
-  \DeclareUnicodeCharacter{00FC}{\"u}%
-  \DeclareUnicodeCharacter{00FD}{\'y}%
+  \DeclareUnicodeCharacterSK{00F8}{\o}%
+  \DeclareUnicodeCharacterSK{00F9}{\`u}%
+  \DeclareUnicodeCharacterSK{00FA}{\'u}%
+  \DeclareUnicodeCharacterSK{00FB}{\^u}%
+  \DeclareUnicodeCharacterSK{00FC}{\"u}%
+  \DeclareUnicodeCharacterSK{00FD}{\'y}%
  \DeclareUnicodeCharacter{00FE}{\th}%
-  \DeclareUnicodeCharacter{00FF}{\"y}%
+  \DeclareUnicodeCharacterSK{00FF}{\"y}%
  %
  \DeclareUnicodeCharacter{0100}{\=A}%
  \DeclareUnicodeCharacter{0101}{\=a}%
@ -11719,6 +11854,9 @@
 \newif\ifpassthroughchars
 \passthroughcharsfalse

+\newif\ifinindexsortkey
+\inindexsortkeyfalse
+
 % For native Unicode handling (XeTeX and LuaTeX),
 % provide a definition macro to replace/pass-through a Unicode character
 %
@ -11730,7 +11868,15 @@
        \uccode`\~="##2\relax
        \uppercase{\gdef~}{%
          \ifpassthroughchars
-            ##1%
+            \ifinindexsortkey
+               \expandafter\ifx\csname usort:#1\endcsname\relax
+                 {##1}%
+               \else
+                 \csname usort:#1\endcsname
+               \fi
+            \else
+              ##1%
+            \fi
          \else
            ##3%
          \fi
--- a/lib/acl-internal.h
+++ b/lib/acl-internal.h
@ -249,17 +249,19 @@ struct permission_context {

 # elif defined GETACL /* Solaris, Cygwin < 2.5 */
  int count;
-  aclent_t *entries;
+  aclent_t *entries
+    _GL_ATTRIBUTE_COUNTED_BY (count);
 #  ifdef ACE_GETACL
  int ace_count;
-  ace_t *ace_entries;
+  ace_t *ace_entries
+    _GL_ATTRIBUTE_COUNTED_BY (ace_count);
 #  endif

 # elif HAVE_GETACL /* HP-UX */
-  struct acl_entry entries[NACLENTRIES];
+  struct acl_entry entries[NACLENTRIES] /* COUNTED_BY (count) */;
  int count;
 #  if HAVE_ACLV_H
-  struct acl aclv_entries[NACLVENTRIES];
+  struct acl aclv_entries[NACLVENTRIES] /* COUNTED_BY (aclv_count) */;
  int aclv_count;
 #  endif

@ -268,7 +270,7 @@ struct permission_context {
  bool have_u;

 # elif HAVE_ACLSORT /* NonStop Kernel */
-  struct acl entries[NACLENTRIES];
+  struct acl entries[NACLENTRIES] /* COUNTED_BY (count) */;
  int count;

 # endif
--- a/lib/acl.h
+++ b/lib/acl.h
@ -48,7 +48,7 @@ struct aclinfo
 {
  /* If 'size' is nonnegative, a buffer holding the concatenation
     of extended attribute names, each terminated by NUL
-     (either u.__gl_acl_ch, or heap-allocated).  */
+     (either u._gl_acl_ch, or heap-allocated).  */
  char *buf;

  /* The number of useful bytes at the start of buf, counting trailing NULs.
@ -72,7 +72,7 @@ struct aclinfo
       trivial NFSv4 ACL (a size used by file-has-acl.c in 2023-2024
       but no longer relevant now), and a different value might be
       better once experience is gained.  For internal use only.  */
-    char __gl_acl_ch[152];
+    char _gl_acl_ch[152];
  } u;
 };

--- a/lib/attribute.h
+++ b/lib/attribute.h
@ -81,8 +81,8 @@

 /* This file uses _GL_ATTRIBUTE_ALLOC_SIZE, _GL_ATTRIBUTE_ALWAYS_INLINE,
   _GL_ATTRIBUTE_ARTIFICIAL, _GL_ATTRIBUTE_COLD, _GL_ATTRIBUTE_CONST,
-   _GL_ATTRIBUTE_DEALLOC, _GL_ATTRIBUTE_DEPRECATED, _GL_ATTRIBUTE_ERROR,
-   _GL_ATTRIBUTE_WARNING, _GL_ATTRIBUTE_EXTERNALLY_VISIBLE,
+   _GL_ATTRIBUTE_COUNTED_BY, _GL_ATTRIBUTE_DEALLOC, _GL_ATTRIBUTE_DEPRECATED,
+   _GL_ATTRIBUTE_ERROR, _GL_ATTRIBUTE_WARNING, _GL_ATTRIBUTE_EXTERNALLY_VISIBLE,
   _GL_ATTRIBUTE_FALLTHROUGH, _GL_ATTRIBUTE_FORMAT, _GL_ATTRIBUTE_LEAF,
   _GL_ATTRIBUTE_MALLOC, _GL_ATTRIBUTE_MAY_ALIAS, _GL_ATTRIBUTE_MAYBE_UNUSED,
   _GL_ATTRIBUTE_NODISCARD, _GL_ATTRIBUTE_NOINLINE, _GL_ATTRIBUTE_NONNULL,
@ -210,6 +210,19 @@
 #define FALLTHROUGH _GL_ATTRIBUTE_FALLTHROUGH


+/* =================== Attributes for runtime diagnostics =================== */
+
+/* Attributes that provide information to the undefined-behaviour sanitizer
+   (UBSAN).  */
+
+/* COUNTED_BY (C) declares that the number of elements of the field is given
+   by C, which must be another field in the same struct.
+   The programmer is responsible for guaranteeing some invariants; see
+   <https://gcc.gnu.org/onlinedocs/gcc/Common-Attributes.html> for details.  */
+/* Applies to struct fields of type array or pointer (to data).  */
+#define COUNTED_BY(c) _GL_ATTRIBUTE_COUNTED_BY (c)
+
+
 /* ================== Attributes for debugging information ================== */

 /* Attributes regarding debugging information emitted by the compiler.  */
--- a/lib/binary-io.c
+++ b/lib/binary-io.c
@ -32,7 +32,7 @@ set_binary_mode (int fd, int mode)
       with console input or console output.  */
    return O_TEXT;
  else
-    return __gl_setmode (fd, mode);
+    return _gl_set_fd_mode (fd, mode);
 }

 #endif
--- a/lib/binary-io.h
+++ b/lib/binary-io.h
@ -38,9 +38,9 @@ _GL_INLINE_HEADER_BEGIN
 #if O_BINARY
 # if defined __EMX__ || defined __DJGPP__ || defined __CYGWIN__
 #  include <io.h> /* declares setmode() */
-#  define __gl_setmode setmode
+#  define _gl_set_fd_mode setmode
 # else
-#  define __gl_setmode _setmode
+#  define _gl_set_fd_mode _setmode
 #  undef fileno
 #  define fileno _fileno
 # endif
@ -49,7 +49,7 @@ _GL_INLINE_HEADER_BEGIN
  /* Use a function rather than a macro, to avoid gcc warnings
     "warning: statement with no effect".  */
 BINARY_IO_INLINE int
-__gl_setmode (_GL_UNUSED int fd, _GL_UNUSED int mode)
+_gl_set_fd_mode (_GL_UNUSED int fd, _GL_UNUSED int mode)
 {
  return O_BINARY;
 }
@ -72,7 +72,7 @@ extern int set_binary_mode (int fd, int mode);
 BINARY_IO_INLINE int
 set_binary_mode (int fd, int mode)
 {
-  return __gl_setmode (fd, mode);
+  return _gl_set_fd_mode (fd, mode);
 }
 #endif

--- a/lib/boot-time-aux.h
+++ b/lib/boot-time-aux.h
@ -16,8 +16,6 @@

 /* Written by Bruno Haible <bruno@clisp.org>.  */

-#define SIZEOF(a) (sizeof(a)/sizeof(a[0]))
-
 #if defined __linux__ || defined __ANDROID__

 /* Store the uptime counter, as managed by the Linux kernel, in *P_UPTIME.
@ -102,7 +100,7 @@ get_linux_boot_time_fallback (struct timespec *p_boot_time)
         modified when a user logs in, i.e. long after boot.  */
      "/var/run/utmp"                 /* seen on Alpine Linux with OpenRC */
    };
-  for (idx_t i = 0; i < SIZEOF (boot_touched_files); i++)
+  for (idx_t i = 0; i < countof (boot_touched_files); i++)
    {
      const char *filename = boot_touched_files[i];
      struct stat statbuf;
@ -214,7 +212,7 @@ get_openbsd_boot_time (struct timespec *p_boot_time)
      "/var/db/host.random",
      "/var/run/utmp"
    };
-  for (idx_t i = 0; i < SIZEOF (boot_touched_files); i++)
+  for (idx_t i = 0; i < countof (boot_touched_files); i++)
    {
      const char *filename = boot_touched_files[i];
      struct stat statbuf;
@ -325,7 +323,7 @@ get_windows_boot_time (struct timespec *p_boot_time)
      "C:\\pagefile.sys"
      #endif
    };
-  for (idx_t i = 0; i < SIZEOF (boot_touched_files); i++)
+  for (idx_t i = 0; i < countof (boot_touched_files); i++)
    {
      const char *filename = boot_touched_files[i];
      struct stat statbuf;
--- a/lib/boot-time.c
+++ b/lib/boot-time.c
@ -21,6 +21,7 @@
 /* Specification.  */
 #include "boot-time.h"

+#include <stdcountof.h>
 #include <stddef.h>
 #include <stdio.h>
 #include <string.h>
@ -94,7 +95,8 @@ get_boot_time_uncached (struct timespec *p_boot_time)
     Solaris' utmpname returns 1 upon success -- which is contrary
     to what the GNU libc version does.  In addition, older GNU libc
     versions are actually void.   */
-  UTMP_NAME_FUNCTION ((char *) UTMP_FILE);
+  static char const utmp_file[] = UTMP_FILE;
+  UTMP_NAME_FUNCTION ((char *) utmp_file);

  SET_UTMP_ENT ();

--- a/lib/boot-time.h
+++ b/lib/boot-time.h
@ -34,7 +34,7 @@ extern "C" {
   The difference can matter in GNU/Linux, where times in /proc/stat
   might be relative to boot time of the host, not the container.

-   This function is not multithread-safe, since on many platforms it
+   This function is not thread-safe, since on many platforms it
   invokes the functions setutxent, getutxent, endutxent.
   These functions may lock a file like /var/log/wtmp (so that we
   don't read garbage when a concurrent process writes to that file),
--- a/lib/byteswap.in.h
+++ b/lib/byteswap.in.h
@ -23,13 +23,14 @@
 #error "Please include config.h first."
 #endif

-/* Define this now, rather than after including stdint.h, in case
-   stdint.h recursively includes us.  This is for Gnulib endian.h.  */
+/* Define this now, rather than after including stdbit.h, in case stdbit.h
+   recursively includes us via stdint.h.  This is for Gnulib endian.h.  */
 #ifndef _GL_BYTESWAP_INLINE
 # define _GL_BYTESWAP_INLINE _GL_INLINE
 #endif

-#include <stdint.h>
+#include <stdbit.h> /* for stdc_memreverse8u* */
+#include <stdint.h> /* for UINT_LEAST64_MAX */

 _GL_INLINE_HEADER_BEGIN

@ -37,38 +38,12 @@ _GL_INLINE_HEADER_BEGIN
 extern "C" {
 #endif

-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)
-# define _GL_BYTESWAP_HAS_BUILTIN_BSWAP16 true
-#elif defined __has_builtin
-# if __has_builtin (__builtin_bswap16)
-#  define _GL_BYTESWAP_HAS_BUILTIN_BSWAP16 true
-# endif
-#endif
-
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
-# define _GL_BYTESWAP_HAS_BUILTIN_BSWAP32 true
-# define _GL_BYTESWAP_HAS_BUILTIN_BSWAP64 true
-#elif defined __has_builtin
-# if __has_builtin (__builtin_bswap32)
-#  define _GL_BYTESWAP_HAS_BUILTIN_BSWAP32 true
-# endif
-# if __has_builtin (__builtin_bswap64)
-#  define _GL_BYTESWAP_HAS_BUILTIN_BSWAP64 true
-# endif
-#endif
-
 /* Given an unsigned 16-bit argument X, return the value corresponding to
   X with reversed byte order.  */
 _GL_BYTESWAP_INLINE uint_least16_t
 bswap_16 (uint_least16_t x)
 {
-#ifdef _GL_BYTESWAP_HAS_BUILTIN_BSWAP16
-  return __builtin_bswap16 (x);
-#else
-  uint_fast16_t mask = 0xff;
-  return (  (x & mask << 8 * 1) >> 8 * 1
-          | (x & mask << 8 * 0) << 8 * 1);
-#endif
+  return stdc_memreverse8u16 (x);
 }

 /* Given an unsigned 32-bit argument X, return the value corresponding to
@ -76,15 +51,7 @@ bswap_16 (uint_least16_t x)
 _GL_BYTESWAP_INLINE uint_least32_t
 bswap_32 (uint_least32_t x)
 {
-#ifdef _GL_BYTESWAP_HAS_BUILTIN_BSWAP32
-  return __builtin_bswap32 (x);
-#else
-  uint_fast32_t mask = 0xff;
-  return (  (x & mask << 8 * 3) >> 8 * 3
-          | (x & mask << 8 * 2) >> 8 * 1
-          | (x & mask << 8 * 1) << 8 * 1
-          | (x & mask << 8 * 0) << 8 * 3);
-#endif
+  return stdc_memreverse8u32 (x);
 }

 #ifdef UINT_LEAST64_MAX
@ -93,19 +60,7 @@ bswap_32 (uint_least32_t x)
 _GL_BYTESWAP_INLINE uint_least64_t
 bswap_64 (uint_least64_t x)
 {
-# ifdef _GL_BYTESWAP_HAS_BUILTIN_BSWAP64
-  return __builtin_bswap64 (x);
-# else
-  uint_fast64_t mask = 0xff;
-  return (  (x & mask << 8 * 7) >> 8 * 7
-          | (x & mask << 8 * 6) >> 8 * 5
-          | (x & mask << 8 * 5) >> 8 * 3
-          | (x & mask << 8 * 4) >> 8 * 1
-          | (x & mask << 8 * 3) << 8 * 1
-          | (x & mask << 8 * 2) << 8 * 3
-          | (x & mask << 8 * 1) << 8 * 5
-          | (x & mask << 8 * 0) << 8 * 7);
-# endif
+  return stdc_memreverse8u64 (x);
 }
 #endif

--- a/lib/careadlinkat.c
+++ b/lib/careadlinkat.c
@ -42,22 +42,17 @@ enum { STACK_BUF_SIZE = 1024 };
 /* Act like careadlinkat (see below), with an additional argument
   STACK_BUF that can be used as temporary storage.

-   If GCC_LINT is defined, do not inline this function with GCC 10.1
-   and later, to avoid creating a pointer to the stack that GCC
+   In GCC 10+, do not inline this function
+   to avoid creating a pointer to the stack that
   -Wreturn-local-addr incorrectly complains about.  See:
   https://gcc.gnu.org/PR93644
   Although the noinline attribute can hurt performance a bit, no better way
-   to pacify GCC is known; even an explicit #pragma does not pacify GCC.
-   When the GCC bug is fixed this workaround should be limited to the
+   to pacify GCC is known; even an explicit #pragma does not pacify GCC
+   10 or 11, or GCC 12+ with -flto.
+   If the GCC bug is fixed this workaround should be limited to the
   broken GCC versions.  */
 #if _GL_GNUC_PREREQ (10, 1)
-# if _GL_GNUC_PREREQ (12, 1)
-#  pragma GCC diagnostic ignored "-Wreturn-local-addr"
-# elif defined GCC_LINT || defined lint
 __attribute__ ((__noinline__))
-# elif __OPTIMIZE__ && !__NO_INLINE__
-#  define GCC_BOGUS_WRETURN_LOCAL_ADDR
-# endif
 #endif
 static char *
 readlink_stk (int fd, char const *filename,
@ -172,10 +167,6 @@ careadlinkat (int fd, char const *filename,
     common case of a symlink of small size, we get away with a
     single small malloc instead of a big malloc followed by a
     shrinking realloc.  */
-  #ifdef GCC_BOGUS_WRETURN_LOCAL_ADDR
-   #warning "GCC might issue a bogus -Wreturn-local-addr warning here."
-   #warning "See <https://gcc.gnu.org/PR93644>."
-  #endif
  char stack_buf[STACK_BUF_SIZE];
  return readlink_stk (fd, filename, buffer, buffer_size, alloc,
                       preadlinkat, stack_buf);
--- a/lib/cdefs.h
+++ b/lib/cdefs.h
@ -669,7 +669,8 @@
 # ifdef __GNUC__
 #  define __restrict_arr	/* Not supported in old GCC.  */
 # else
-#  if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
+#  if (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L \
+       && !defined _MSC_VER)
 #   define __restrict_arr	restrict
 #  else
 /* Some other non-C99 compiler.  */
--- a/lib/diffseq.h
+++ b/lib/diffseq.h
@ -82,10 +82,11 @@
 #error "Please include config.h first."
 #endif

-/* Maximum value of type OFFSET.  */
+/* Maximum value of type OFFSET.  The 1u pacifies -Wuseless-cast, and
+   unlike a compound literal can appear in an integer constant expression.  */
 #ifndef OFFSET_MAX
 # define OFFSET_MAX \
-   ((((OFFSET) 1 << (sizeof (OFFSET) * CHAR_BIT - 2)) - 1) * 2 + 1)
+   ((((OFFSET) 1u << (sizeof (OFFSET) * CHAR_BIT - 2)) - 1) * 2 + 1)
 #endif

 /* Default to no early abort.  */
--- a/lib/dynarray.h
+++ b/lib/dynarray.h
@ -249,11 +249,11 @@ static DYNARRAY_ELEMENT *
 /* The implementation is imported from glibc.  */

 /* Avoid possible conflicts with symbols exported by the GNU libc.  */
-#define __libc_dynarray_at_failure gl_dynarray_at_failure
-#define __libc_dynarray_emplace_enlarge gl_dynarray_emplace_enlarge
-#define __libc_dynarray_finalize gl_dynarray_finalize
-#define __libc_dynarray_resize_clear gl_dynarray_resize_clear
-#define __libc_dynarray_resize gl_dynarray_resize
+#define __libc_dynarray_at_failure _gl_dynarray_at_failure
+#define __libc_dynarray_emplace_enlarge _gl_dynarray_emplace_enlarge
+#define __libc_dynarray_finalize _gl_dynarray_finalize
+#define __libc_dynarray_resize_clear _gl_dynarray_resize_clear
+#define __libc_dynarray_resize _gl_dynarray_resize

 #if defined DYNARRAY_STRUCT || defined DYNARRAY_ELEMENT || defined DYNARRAY_PREFIX

--- a/lib/endian.in.h
+++ b/lib/endian.in.h
@ -109,7 +109,7 @@ _GL_INLINE_HEADER_BEGIN
 extern "C" {
 #endif

-/* These declarations are needed if Gnulib byteswap.h -> stdint.h ->
+/* These declarations are needed if Gnulib byteswap.h -> stdbit.h -> stdint.h ->
   sys/types.h -> endian.h -> Gnulib byteswap.h, the last of which is blocked
   by its include guard so the functions are not yet declared.  */
 #ifdef _GL_BYTESWAP_INLINE
@ -120,138 +120,174 @@ _GL_BYTESWAP_INLINE uint_least64_t bswap_64 (uint_least64_t);

 /* Big endian to host.  */

+#if !GNULIB_defined_be16toh
 _GL_ENDIAN_INLINE uint16_t
 be16toh (uint16_t x)
 {
-#if BYTE_ORDER == BIG_ENDIAN
-  return x;
-#else
-  return bswap_16 (x);
-#endif
-}
-
-_GL_ENDIAN_INLINE uint32_t
-be32toh (uint32_t x)
-{
-#if BYTE_ORDER == BIG_ENDIAN
-  return x;
-#else
-  return bswap_32 (x);
-#endif
-}
-
-#ifdef UINT64_MAX
-_GL_ENDIAN_INLINE uint64_t
-be64toh (uint64_t x)
-{
 # if BYTE_ORDER == BIG_ENDIAN
  return x;
 # else
-  return bswap_64 (x);
+  return bswap_16 (x);
 # endif
 }
+# define GNULIB_defined_be16toh 1
+#endif
+
+#if !GNULIB_defined_be32toh
+_GL_ENDIAN_INLINE uint32_t
+be32toh (uint32_t x)
+{
+# if BYTE_ORDER == BIG_ENDIAN
+  return x;
+# else
+  return bswap_32 (x);
+# endif
+}
+# define GNULIB_defined_be32toh 1
+#endif
+
+#ifdef UINT64_MAX
+# if !GNULIB_defined_be64toh
+_GL_ENDIAN_INLINE uint64_t
+be64toh (uint64_t x)
+{
+#  if BYTE_ORDER == BIG_ENDIAN
+  return x;
+#  else
+  return bswap_64 (x);
+#  endif
+}
+#  define GNULIB_defined_be64toh 1
+# endif
 #endif

 /* Host to big endian.  */

+#if !GNULIB_defined_htobe16
 _GL_ENDIAN_INLINE uint16_t
 htobe16 (uint16_t x)
 {
-#if BYTE_ORDER == BIG_ENDIAN
-  return x;
-#else
-  return bswap_16 (x);
-#endif
-}
-
-_GL_ENDIAN_INLINE uint32_t
-htobe32 (uint32_t x)
-{
-#if BYTE_ORDER == BIG_ENDIAN
-  return x;
-#else
-  return bswap_32 (x);
-#endif
-}
-
-#ifdef UINT64_MAX
-_GL_ENDIAN_INLINE uint64_t
-htobe64 (uint64_t x)
-{
 # if BYTE_ORDER == BIG_ENDIAN
  return x;
 # else
-  return bswap_64 (x);
+  return bswap_16 (x);
 # endif
 }
+# define GNULIB_defined_htobe16 1
+#endif
+
+#if !GNULIB_defined_htobe32
+_GL_ENDIAN_INLINE uint32_t
+htobe32 (uint32_t x)
+{
+# if BYTE_ORDER == BIG_ENDIAN
+  return x;
+# else
+  return bswap_32 (x);
+# endif
+}
+# define GNULIB_defined_htobe32 1
+#endif
+
+#ifdef UINT64_MAX
+# if !GNULIB_defined_htobe64
+_GL_ENDIAN_INLINE uint64_t
+htobe64 (uint64_t x)
+{
+#  if BYTE_ORDER == BIG_ENDIAN
+  return x;
+#  else
+  return bswap_64 (x);
+#  endif
+}
+#  define GNULIB_defined_htobe64 1
+# endif
 #endif

 /* Little endian to host.  */

+#if !GNULIB_defined_le16toh
 _GL_ENDIAN_INLINE uint16_t
 le16toh (uint16_t x)
 {
-#if BYTE_ORDER == BIG_ENDIAN
-  return bswap_16 (x);
-#else
-  return x;
-#endif
-}
-
-_GL_ENDIAN_INLINE uint32_t
-le32toh (uint32_t x)
-{
-#if BYTE_ORDER == BIG_ENDIAN
-  return bswap_32 (x);
-#else
-  return x;
-#endif
-}
-
-#ifdef UINT64_MAX
-_GL_ENDIAN_INLINE uint64_t
-le64toh (uint64_t x)
-{
 # if BYTE_ORDER == BIG_ENDIAN
-  return bswap_64 (x);
+  return bswap_16 (x);
 # else
  return x;
 # endif
 }
+# define GNULIB_defined_le16toh 1
+#endif
+
+#if !GNULIB_defined_le32toh
+_GL_ENDIAN_INLINE uint32_t
+le32toh (uint32_t x)
+{
+# if BYTE_ORDER == BIG_ENDIAN
+  return bswap_32 (x);
+# else
+  return x;
+# endif
+}
+# define GNULIB_defined_le32toh 1
+#endif
+
+#ifdef UINT64_MAX
+# if !GNULIB_defined_le64toh
+_GL_ENDIAN_INLINE uint64_t
+le64toh (uint64_t x)
+{
+#  if BYTE_ORDER == BIG_ENDIAN
+  return bswap_64 (x);
+#  else
+  return x;
+#  endif
+}
+#  define GNULIB_defined_le64toh 1
+# endif
 #endif

 /* Host to little endian.  */

+#if !GNULIB_defined_htole16
 _GL_ENDIAN_INLINE uint16_t
 htole16 (uint16_t x)
 {
-#if BYTE_ORDER == BIG_ENDIAN
-  return bswap_16 (x);
-#else
-  return x;
-#endif
-}
-
-_GL_ENDIAN_INLINE uint32_t
-htole32 (uint32_t x)
-{
-#if BYTE_ORDER == BIG_ENDIAN
-  return bswap_32 (x);
-#else
-  return x;
-#endif
-}
-
-#ifdef UINT64_MAX
-_GL_ENDIAN_INLINE uint64_t
-htole64 (uint64_t x)
-{
 # if BYTE_ORDER == BIG_ENDIAN
-  return bswap_64 (x);
+  return bswap_16 (x);
 # else
  return x;
 # endif
 }
+# define GNULIB_defined_htole16 1
+#endif
+
+#if !GNULIB_defined_htole32
+_GL_ENDIAN_INLINE uint32_t
+htole32 (uint32_t x)
+{
+# if BYTE_ORDER == BIG_ENDIAN
+  return bswap_32 (x);
+# else
+  return x;
+# endif
+}
+# define GNULIB_defined_htole32 1
+#endif
+
+#ifdef UINT64_MAX
+# if !GNULIB_defined_htole64
+_GL_ENDIAN_INLINE uint64_t
+htole64 (uint64_t x)
+{
+#  if BYTE_ORDER == BIG_ENDIAN
+  return bswap_64 (x);
+#  else
+  return x;
+#  endif
+}
+#  define GNULIB_defined_htole64 1
+# endif
 #endif

 #ifdef __cplusplus
--- a/lib/file-has-acl.c
+++ b/lib/file-has-acl.c
@ -160,8 +160,8 @@ aclinfo_has_xattr (struct aclinfo const *ai, char const *xattr)
 static void
 get_aclinfo (int fd, char const *name, struct aclinfo *ai, int flags)
 {
-  ai->buf = ai->u.__gl_acl_ch;
-  ssize_t acl_alloc = sizeof ai->u.__gl_acl_ch;
+  ai->buf = ai->u._gl_acl_ch;
+  ssize_t acl_alloc = sizeof ai->u._gl_acl_ch;

  if (! (USE_ACL || flags & ACL_GET_SCONTEXT))
    ai->size = 0;
@ -194,10 +194,10 @@ get_aclinfo (int fd, char const *name, struct aclinfo *ai, int flags)
          /* Grow allocation to at least 'size'.  Grow it by a nontrivial
             amount, to defend against denial of service by an adversary
             that fiddles with ACLs.  */
-          if (ai->buf != ai->u.__gl_acl_ch)
+          if (ai->buf != ai->u._gl_acl_ch)
            {
              free (ai->buf);
-              ai->buf = ai->u.__gl_acl_ch;
+              ai->buf = ai->u._gl_acl_ch;
            }
          if (ckd_add (&acl_alloc, acl_alloc, acl_alloc >> 1))
            acl_alloc = SSIZE_MAX;
@ -297,7 +297,7 @@ aclinfo_scontext_free (char *scontext)
 void
 aclinfo_free (struct aclinfo *ai)
 {
-  if (ai->buf != ai->u.__gl_acl_ch)
+  if (ai->buf != ai->u._gl_acl_ch)
    free (ai->buf);
  aclinfo_scontext_free (ai->scontext);
 }
@ -510,7 +510,7 @@ fdfile_has_aclinfo (MAYBE_UNUSED int fd,

 #else /* !USE_LINUX_XATTR */

-  ai->buf = ai->u.__gl_acl_ch;
+  ai->buf = ai->u._gl_acl_ch;
  ai->size = -1;
  ai->u.err = ENOTSUP;
  ai->scontext = (char *) UNKNOWN_SECURITY_CONTEXT;
--- a/lib/fsusage.c
+++ b/lib/fsusage.c
@ -57,7 +57,7 @@
    && (~ (x) == (sizeof (x) < sizeof (int) \
                  ? - (1 << (sizeof (x) * CHAR_BIT)) \
                  : 0))) \
-   ? UINTMAX_MAX : (uintmax_t) (x))
+   ? UINTMAX_MAX : (uintmax_t) {(x)})

 /* Extract the top bit of X as an uintmax_t value.  */
 #define EXTRACT_TOP_BIT(x) ((x) \
--- a/lib/gettext.h
+++ b/lib/gettext.h
@ -60,10 +60,40 @@
 # endif

 /* Disabled NLS.  */
+/* When gcc is used with option -Wformat=2, we need to silence
+   "warning: format not a string literal, argument types not checked [-Wformat-nonliteral]"
+   warnings that would occur at every invocation of a *gettext function
+   in a *printf format string position.
+   Do this with inline functions when possible, namely for gettext, dgettext,
+   dcgettext, which are known to gcc as "external built-ins".
+   It is not ideal to ignore the possible side effects done in the
+   Domainname and Category arguments, but it's better than to have a
+   warning at every invocation in a format string position.  */
+/* When clang is used with option -Wformat=2, we need to silence
+   "warning: format string is not a string literal [-Wformat-nonliteral]"
+   warnings that would occur at every invocation of a *gettext function
+   in a *printf format string position.
+   It is not ideal to ignore the possible side effects done in the
+   Domainname and Category arguments, but it's better than to have a
+   warning at every invocation in a format string position.  */
+/* These warnings would not occur with enabled NLS.  */
+/* A test case:
+   ================================ foo.c ================================
+   #include <stdio.h>
+   #include "gettext.h"
+   void foo (int n)
+   {
+     printf (gettext ("foo %d"), n);
+     printf (dgettext ("toto", "foo %d"), n);
+     printf (dcgettext ("toto", "foo %d", LC_MESSAGES), n);
+     printf (ngettext ("foo %d", "bar %d", n), n);
+     printf (dngettext ("toto", "foo %d", "bar %d", n), n);
+     printf (dcngettext ("toto", "foo %d", "bar %d", n, LC_MESSAGES), n);
+   }
+   =======================================================================
+   $CC -Wformat=2 -S foo.c
+ */
 # if defined __GNUC__ && !defined __clang__ && !defined __cplusplus
-/* Use inline functions, to avoid warnings
-     warning: format not a string literal and no format arguments
-   that don't occur with enabled NLS.  */
 /* The return type 'const char *' serves the purpose of producing warnings
   for invalid uses of the value returned from these functions.  */
 #  if __GNUC__ >= 9
@ -118,36 +148,80 @@ dcgettext (const char *domain, const char *msgid, int category)
 #  if __GNUC__ >= 9
 #   pragma GCC diagnostic pop
 #  endif
-# else
-/* The casts to 'const char *' serve the purpose of producing warnings
-   for invalid uses of the value returned from these functions.  */
+# elif defined __clang__
 #  undef gettext
 #  define gettext(Msgid) ((const char *) (Msgid))
 #  undef dgettext
-#  define dgettext(Domainname, Msgid) ((void) (Domainname), gettext (Msgid))
+#  define dgettext(Domainname, Msgid) gettext (Msgid)
+#  undef dcgettext
+#  define dcgettext(Domainname, Msgid, Category) dgettext (Domainname, Msgid)
+# else
+/* The conversions to 'const char *' via compound literals serve the purpose
+   of producing warnings for invalid uses of the value returned from these
+   functions and for invalid-typed Msgid arguments.  */
+#  undef gettext
+#  define gettext(Msgid) ((const char *) {(Msgid)})
+/* The conversions via compound literals serve the purpose of producing warnings
+   for invalid-typed arguments.  */
+#  undef dgettext
+#  define dgettext(Domainname, Msgid) \
+     ((void) (const char *) {(Domainname)}, gettext (Msgid))
 #  undef dcgettext
 #  define dcgettext(Domainname, Msgid, Category) \
-     ((void) (Category), dgettext (Domainname, Msgid))
+     ((void) (int) {(Category)}, dgettext (Domainname, Msgid))
 # endif
-# undef ngettext
-# define ngettext(Msgid1, Msgid2, N) \
-    ((N) == 1 \
-     ? ((void) (Msgid2), (const char *) (Msgid1)) \
-     : ((void) (Msgid1), (const char *) (Msgid2)))
-# undef dngettext
-# define dngettext(Domainname, Msgid1, Msgid2, N) \
-    ((void) (Domainname), ngettext (Msgid1, Msgid2, N))
-# undef dcngettext
-# define dcngettext(Domainname, Msgid1, Msgid2, N, Category) \
-    ((void) (Category), dngettext (Domainname, Msgid1, Msgid2, N))
+
+# if (defined __GNUC__ && defined __cplusplus) || defined __clang__
+#  undef ngettext
+#  define ngettext(Msgid1, Msgid2, N) \
+     ((N) == 1 ? (const char *) (Msgid1) : (const char *) (Msgid2))
+#  undef dngettext
+#  define dngettext(Domainname, Msgid1, Msgid2, N) \
+     ngettext (Msgid1, Msgid2, N)
+#  undef dcngettext
+#  define dcngettext(Domainname, Msgid1, Msgid2, N, Category) \
+     dngettext (Domainname, Msgid1, Msgid2, N)
+# elif defined __GNUC__ && !defined __cplusplus
+/* Silence -Wuseless-cast warnings.  */
+#  if __GNUC__ >= 14
+#   pragma GCC diagnostic ignored "-Wuseless-cast"
+#  endif
+#  undef ngettext
+#  define ngettext(Msgid1, Msgid2, N) \
+     ((N) == 1 ? (const char *) (Msgid1) : (const char *) (Msgid2))
+#  undef dngettext
+#  define dngettext(Domainname, Msgid1, Msgid2, N) \
+     ((void) (const char *) (Domainname), ngettext (Msgid1, Msgid2, N))
+#  undef dcngettext
+#  define dcngettext(Domainname, Msgid1, Msgid2, N, Category) \
+     ((void) (int) (Category), dngettext (Domainname, Msgid1, Msgid2, N))
+# else
+/* The conversions to 'const char *' via compound literals serve the purpose
+   of producing warnings for invalid uses of the value returned from these
+   functions and for invalid-typed Msgid1 and Msgid2 arguments.  */
+#  undef ngettext
+#  define ngettext(Msgid1, Msgid2, N) \
+     ((N) == 1 \
+      ? ((void) (Msgid2), (const char *) {(Msgid1)}) \
+      : ((void) (Msgid1), (const char *) {(Msgid2)}))
+/* The conversions via compound literals serve the purpose of producing warnings
+   for invalid-typed arguments.  */
+#  undef dngettext
+#  define dngettext(Domainname, Msgid1, Msgid2, N) \
+     ((void) (const char *) {(Domainname)}, ngettext (Msgid1, Msgid2, N))
+#  undef dcngettext
+#  define dcngettext(Domainname, Msgid1, Msgid2, N, Category) \
+     ((void) (int) {(Category)}, dngettext (Domainname, Msgid1, Msgid2, N))
+# endif
+
 # undef textdomain
-# define textdomain(Domainname) ((const char *) (Domainname))
+# define textdomain(Domainname) ((const char *) {(Domainname)})
 # undef bindtextdomain
 # define bindtextdomain(Domainname, Dirname) \
-    ((void) (Domainname), (const char *) (Dirname))
+    ((void) (const char *) {(Domainname)}, (const char *) {(Dirname)})
 # undef bind_textdomain_codeset
 # define bind_textdomain_codeset(Domainname, Codeset) \
-    ((void) (Domainname), (const char *) (Codeset))
+    ((void) (const char *) {(Domainname)}, (const char *) {(Codeset)})

 #endif

@ -178,6 +252,11 @@ dcgettext (const char *domain, const char *msgid, int category)
   The letter 'p' stands for 'particular' or 'special'.  */

 #include <locale.h> /* for LC_MESSAGES */
+/* The LC_MESSAGES locale category is specified in POSIX, but not in ISO C.
+   On systems that don't define it, use the same value as GNU libintl.  */
+#if !defined LC_MESSAGES
+# define LC_MESSAGES 1729
+#endif

 #ifdef DEFAULT_TEXT_DOMAIN
 # define pgettext(Msgctxt, Msgid) \
@ -204,11 +283,9 @@ dcgettext (const char *domain, const char *msgid, int category)

 #if defined __GNUC__ || defined __clang__
 __inline
-#else
-#ifdef __cplusplus
+#elif defined __cplusplus
 inline
 #endif
-#endif
 static const char *
 pgettext_aux (const char *domain,
              const char *msg_ctxt_id, const char *msgid,
@ -223,11 +300,9 @@ pgettext_aux (const char *domain,

 #if defined __GNUC__ || defined __clang__
 __inline
-#else
-#ifdef __cplusplus
+#elif defined __cplusplus
 inline
 #endif
-#endif
 static const char *
 npgettext_aux (const char *domain,
               const char *msg_ctxt_id, const char *msgid,
@ -274,11 +349,9 @@ npgettext_aux (const char *domain,

 #if defined __GNUC__ || defined __clang__
 __inline
-#else
-#ifdef __cplusplus
+#elif defined __cplusplus
 inline
 #endif
-#endif
 static const char *
 dcpgettext_expr (const char *domain,
                 const char *msgctxt, const char *msgid,
@ -320,11 +393,9 @@ dcpgettext_expr (const char *domain,

 #if defined __GNUC__ || defined __clang__
 __inline
-#else
-#ifdef __cplusplus
+#elif defined __cplusplus
 inline
 #endif
-#endif
 static const char *
 dcnpgettext_expr (const char *domain,
                  const char *msgctxt, const char *msgid,
--- a/lib/gnulib.mk.in
+++ b/lib/gnulib.mk.in
@ -35,7 +35,13 @@
 #  --macro-prefix=gl \
 #  --no-vc-files \
 #  --avoid=access \
-#  --avoid=btowc \
+#  --avoid=btoc32 \
+#  --avoid=c32_apply_type_test \
+#  --avoid=c32_get_type_test \
+#  --avoid=c32isalnum \
+#  --avoid=c32rtomb \
+#  --avoid=c32tolower \
+#  --avoid=c32toupper \
 #  --avoid=chmod \
 #  --avoid=close \
 #  --avoid=crypto/af_alg \
@ -43,17 +49,13 @@
 #  --avoid=fchdir \
 #  --avoid=fstat \
 #  --avoid=gnulib-i18n \
-#  --avoid=iswblank \
-#  --avoid=iswctype \
-#  --avoid=iswdigit \
-#  --avoid=iswxdigit \
 #  --avoid=langinfo-h \
 #  --avoid=libgmp-mpq \
 #  --avoid=localcharset \
-#  --avoid=locale-h \
+#  --avoid=localeinfo \
 #  --avoid=localename-unsafe-limited \
 #  --avoid=lock \
-#  --avoid=mbrtowc \
+#  --avoid=mbrtoc32-regular \
 #  --avoid=mbsinit \
 #  --avoid=memchr \
 #  --avoid=mkdir \
@ -63,14 +65,12 @@
 #  --avoid=openat-die \
 #  --avoid=opendir \
 #  --avoid=pthread-h \
-#  --avoid=raise \
 #  --avoid=save-cwd \
 #  --avoid=select \
 #  --avoid=setenv \
 #  --avoid=sigprocmask \
 #  --avoid=stat \
 #  --avoid=std-gnu11 \
-#  --avoid=stdarg-h \
 #  --avoid=strncpy \
 #  --avoid=threadlib \
 #  --avoid=tzset \
@ -78,9 +78,7 @@
 #  --avoid=utime \
 #  --avoid=utime-h \
 #  --avoid=wchar-h \
-#  --avoid=wcrtomb \
-#  --avoid=wctype \
-#  --avoid=wctype-h \
+#  --avoid=uchar-h \
 #  alignasof \
 #  alloca-opt \
 #  attribute \
@ -254,6 +252,7 @@ CPPFLAGS = @CPPFLAGS@
 CRYPTOLIB = @CRYPTOLIB@
 CXX = @CXX@
 CXXFLAGS = @CXXFLAGS@
+CXX_HAVE_STDCOUNTOF_H = @CXX_HAVE_STDCOUNTOF_H@
 CYGWIN_OBJ = @CYGWIN_OBJ@
 C_SWITCH_MACHINE = @C_SWITCH_MACHINE@
 C_SWITCH_SYSTEM = @C_SWITCH_SYSTEM@
@ -372,6 +371,7 @@ GL_GENERATE_LIMITS_H_CONDITION = @GL_GENERATE_LIMITS_H_CONDITION@
 GL_GENERATE_MINI_GMP_H_CONDITION = @GL_GENERATE_MINI_GMP_H_CONDITION@
 GL_GENERATE_STDBIT_H_CONDITION = @GL_GENERATE_STDBIT_H_CONDITION@
 GL_GENERATE_STDCKDINT_H_CONDITION = @GL_GENERATE_STDCKDINT_H_CONDITION@
+GL_GENERATE_STDCOUNTOF_H_CONDITION = @GL_GENERATE_STDCOUNTOF_H_CONDITION@
 GL_GENERATE_STDDEF_H_CONDITION = @GL_GENERATE_STDDEF_H_CONDITION@
 GL_GENERATE_STDINT_H_CONDITION = @GL_GENERATE_STDINT_H_CONDITION@
 GL_GNULIB_ABORT_DEBUG = @GL_GNULIB_ABORT_DEBUG@
@ -621,6 +621,28 @@ GL_GNULIB_SNZPRINTF = @GL_GNULIB_SNZPRINTF@
 GL_GNULIB_SPRINTF_POSIX = @GL_GNULIB_SPRINTF_POSIX@
 GL_GNULIB_STACK_TRACE = @GL_GNULIB_STACK_TRACE@
 GL_GNULIB_STAT = @GL_GNULIB_STAT@
+GL_GNULIB_STDC_BIT_CEIL = @GL_GNULIB_STDC_BIT_CEIL@
+GL_GNULIB_STDC_BIT_FLOOR = @GL_GNULIB_STDC_BIT_FLOOR@
+GL_GNULIB_STDC_BIT_WIDTH = @GL_GNULIB_STDC_BIT_WIDTH@
+GL_GNULIB_STDC_COUNT_ONES = @GL_GNULIB_STDC_COUNT_ONES@
+GL_GNULIB_STDC_COUNT_ZEROS = @GL_GNULIB_STDC_COUNT_ZEROS@
+GL_GNULIB_STDC_FIRST_LEADING_ONE = @GL_GNULIB_STDC_FIRST_LEADING_ONE@
+GL_GNULIB_STDC_FIRST_LEADING_ZERO = @GL_GNULIB_STDC_FIRST_LEADING_ZERO@
+GL_GNULIB_STDC_FIRST_TRAILING_ONE = @GL_GNULIB_STDC_FIRST_TRAILING_ONE@
+GL_GNULIB_STDC_FIRST_TRAILING_ZERO = @GL_GNULIB_STDC_FIRST_TRAILING_ZERO@
+GL_GNULIB_STDC_HAS_SINGLE_BIT = @GL_GNULIB_STDC_HAS_SINGLE_BIT@
+GL_GNULIB_STDC_LEADING_ONES = @GL_GNULIB_STDC_LEADING_ONES@
+GL_GNULIB_STDC_LEADING_ZEROS = @GL_GNULIB_STDC_LEADING_ZEROS@
+GL_GNULIB_STDC_LOAD8 = @GL_GNULIB_STDC_LOAD8@
+GL_GNULIB_STDC_LOAD8_ALIGNED = @GL_GNULIB_STDC_LOAD8_ALIGNED@
+GL_GNULIB_STDC_MEMREVERSE8 = @GL_GNULIB_STDC_MEMREVERSE8@
+GL_GNULIB_STDC_MEMREVERSE8U = @GL_GNULIB_STDC_MEMREVERSE8U@
+GL_GNULIB_STDC_ROTATE_LEFT = @GL_GNULIB_STDC_ROTATE_LEFT@
+GL_GNULIB_STDC_ROTATE_RIGHT = @GL_GNULIB_STDC_ROTATE_RIGHT@
+GL_GNULIB_STDC_STORE8 = @GL_GNULIB_STDC_STORE8@
+GL_GNULIB_STDC_STORE8_ALIGNED = @GL_GNULIB_STDC_STORE8_ALIGNED@
+GL_GNULIB_STDC_TRAILING_ONES = @GL_GNULIB_STDC_TRAILING_ONES@
+GL_GNULIB_STDC_TRAILING_ZEROS = @GL_GNULIB_STDC_TRAILING_ZEROS@
 GL_GNULIB_STDIO_H_NONBLOCKING = @GL_GNULIB_STDIO_H_NONBLOCKING@
 GL_GNULIB_STDIO_H_SIGPIPE = @GL_GNULIB_STDIO_H_SIGPIPE@
 GL_GNULIB_STPCPY = @GL_GNULIB_STPCPY@
@ -681,6 +703,7 @@ GL_GNULIB_UNLOCKPT = @GL_GNULIB_UNLOCKPT@
 GL_GNULIB_UNSETENV = @GL_GNULIB_UNSETENV@
 GL_GNULIB_USLEEP = @GL_GNULIB_USLEEP@
 GL_GNULIB_UTIMENSAT = @GL_GNULIB_UTIMENSAT@
+GL_GNULIB_VAPRINTF = @GL_GNULIB_VAPRINTF@
 GL_GNULIB_VASPRINTF = @GL_GNULIB_VASPRINTF@
 GL_GNULIB_VASZPRINTF = @GL_GNULIB_VASZPRINTF@
 GL_GNULIB_VDPRINTF = @GL_GNULIB_VDPRINTF@
@ -701,20 +724,7 @@ GL_GNULIB_WCTOMB = @GL_GNULIB_WCTOMB@
 GL_GNULIB_WRITE = @GL_GNULIB_WRITE@
 GL_GNULIB_ZPRINTF = @GL_GNULIB_ZPRINTF@
 GL_GNULIB__EXIT = @GL_GNULIB__EXIT@
-GL_STDC_BIT_CEIL = @GL_STDC_BIT_CEIL@
-GL_STDC_BIT_FLOOR = @GL_STDC_BIT_FLOOR@
-GL_STDC_BIT_WIDTH = @GL_STDC_BIT_WIDTH@
-GL_STDC_COUNT_ONES = @GL_STDC_COUNT_ONES@
-GL_STDC_COUNT_ZEROS = @GL_STDC_COUNT_ZEROS@
-GL_STDC_FIRST_LEADING_ONE = @GL_STDC_FIRST_LEADING_ONE@
-GL_STDC_FIRST_LEADING_ZERO = @GL_STDC_FIRST_LEADING_ZERO@
-GL_STDC_FIRST_TRAILING_ONE = @GL_STDC_FIRST_TRAILING_ONE@
-GL_STDC_FIRST_TRAILING_ZERO = @GL_STDC_FIRST_TRAILING_ZERO@
-GL_STDC_HAS_SINGLE_BIT = @GL_STDC_HAS_SINGLE_BIT@
-GL_STDC_LEADING_ONES = @GL_STDC_LEADING_ONES@
-GL_STDC_LEADING_ZEROS = @GL_STDC_LEADING_ZEROS@
-GL_STDC_TRAILING_ONES = @GL_STDC_TRAILING_ONES@
-GL_STDC_TRAILING_ZEROS = @GL_STDC_TRAILING_ZEROS@
+GL_HAVE_STDBIT_H_CONDITION = @GL_HAVE_STDBIT_H_CONDITION@
 GMALLOC_OBJ = @GMALLOC_OBJ@
 GMP_H = @GMP_H@
 GNULIBHEADERS_OVERRIDE_WINT_T = @GNULIBHEADERS_OVERRIDE_WINT_T@
@ -924,7 +934,9 @@ HAVE_SIGNED_WINT_T = @HAVE_SIGNED_WINT_T@
 HAVE_SIGSET_T = @HAVE_SIGSET_T@
 HAVE_SLEEP = @HAVE_SLEEP@
 HAVE_SPAWN_H = @HAVE_SPAWN_H@
+HAVE_STDBIT_H = @HAVE_STDBIT_H@
 HAVE_STDCKDINT_H = @HAVE_STDCKDINT_H@
+HAVE_STDCOUNTOF_H = @HAVE_STDCOUNTOF_H@
 HAVE_STDINT_H = @HAVE_STDINT_H@
 HAVE_STPCPY = @HAVE_STPCPY@
 HAVE_STPNCPY = @HAVE_STPNCPY@
@ -1104,7 +1116,9 @@ NEXT_AS_FIRST_DIRECTIVE_GETOPT_H = @NEXT_AS_FIRST_DIRECTIVE_GETOPT_H@
 NEXT_AS_FIRST_DIRECTIVE_INTTYPES_H = @NEXT_AS_FIRST_DIRECTIVE_INTTYPES_H@
 NEXT_AS_FIRST_DIRECTIVE_LIMITS_H = @NEXT_AS_FIRST_DIRECTIVE_LIMITS_H@
 NEXT_AS_FIRST_DIRECTIVE_SIGNAL_H = @NEXT_AS_FIRST_DIRECTIVE_SIGNAL_H@
+NEXT_AS_FIRST_DIRECTIVE_STDBIT_H = @NEXT_AS_FIRST_DIRECTIVE_STDBIT_H@
 NEXT_AS_FIRST_DIRECTIVE_STDCKDINT_H = @NEXT_AS_FIRST_DIRECTIVE_STDCKDINT_H@
+NEXT_AS_FIRST_DIRECTIVE_STDCOUNTOF_H = @NEXT_AS_FIRST_DIRECTIVE_STDCOUNTOF_H@
 NEXT_AS_FIRST_DIRECTIVE_STDDEF_H = @NEXT_AS_FIRST_DIRECTIVE_STDDEF_H@
 NEXT_AS_FIRST_DIRECTIVE_STDINT_H = @NEXT_AS_FIRST_DIRECTIVE_STDINT_H@
 NEXT_AS_FIRST_DIRECTIVE_STDIO_H = @NEXT_AS_FIRST_DIRECTIVE_STDIO_H@
@ -1125,7 +1139,9 @@ NEXT_GETOPT_H = @NEXT_GETOPT_H@
 NEXT_INTTYPES_H = @NEXT_INTTYPES_H@
 NEXT_LIMITS_H = @NEXT_LIMITS_H@
 NEXT_SIGNAL_H = @NEXT_SIGNAL_H@
+NEXT_STDBIT_H = @NEXT_STDBIT_H@
 NEXT_STDCKDINT_H = @NEXT_STDCKDINT_H@
+NEXT_STDCOUNTOF_H = @NEXT_STDCOUNTOF_H@
 NEXT_STDDEF_H = @NEXT_STDDEF_H@
 NEXT_STDINT_H = @NEXT_STDINT_H@
 NEXT_STDIO_H = @NEXT_STDIO_H@
@ -1391,6 +1407,7 @@ SQLITE3_CFLAGS = @SQLITE3_CFLAGS@
 SQLITE3_LIBS = @SQLITE3_LIBS@
 STDBIT_H = @STDBIT_H@
 STDCKDINT_H = @STDCKDINT_H@
+STDCOUNTOF_H = @STDCOUNTOF_H@
 STDDEF_H = @STDDEF_H@
 STDDEF_NOT_IDEMPOTENT = @STDDEF_NOT_IDEMPOTENT@
 STDINT_H = @STDINT_H@
@ -1516,6 +1533,7 @@ gl_GNULIB_ENABLED_issymlinkat_CONDITION = @gl_GNULIB_ENABLED_issymlinkat_CONDITI
 gl_GNULIB_ENABLED_lchmod_CONDITION = @gl_GNULIB_ENABLED_lchmod_CONDITION@
 gl_GNULIB_ENABLED_open_CONDITION = @gl_GNULIB_ENABLED_open_CONDITION@
 gl_GNULIB_ENABLED_rawmemchr_CONDITION = @gl_GNULIB_ENABLED_rawmemchr_CONDITION@
+gl_GNULIB_ENABLED_stdc_memreverse8u_CONDITION = @gl_GNULIB_ENABLED_stdc_memreverse8u_CONDITION@
 gl_GNULIB_ENABLED_strtoll_CONDITION = @gl_GNULIB_ENABLED_strtoll_CONDITION@
 gl_GNULIB_ENABLED_utimens_CONDITION = @gl_GNULIB_ENABLED_utimens_CONDITION@
 gl_GNULIB_ENABLED_verify_CONDITION = @gl_GNULIB_ENABLED_verify_CONDITION@
@ -3199,23 +3217,36 @@ BUILT_SOURCES += $(STDBIT_H)
 ifneq (,$(GL_GENERATE_STDBIT_H_CONDITION))
 stdbit.h: stdbit.in.h $(top_builddir)/config.status
 	$(gl_V_at)$(SED_HEADER_STDOUT) \
-	  -e 's/@''GL_STDC_LEADING_ZEROS''@/$(GL_STDC_LEADING_ZEROS)/g' \
-	  -e 's/@''GL_STDC_LEADING_ONES''@/$(GL_STDC_LEADING_ONES)/g' \
-	  -e 's/@''GL_STDC_TRAILING_ZEROS''@/$(GL_STDC_TRAILING_ZEROS)/g' \
-	  -e 's/@''GL_STDC_TRAILING_ONES''@/$(GL_STDC_TRAILING_ONES)/g' \
-	  -e 's/@''GL_STDC_FIRST_LEADING_ZERO''@/$(GL_STDC_FIRST_LEADING_ZERO)/g' \
-	  -e 's/@''GL_STDC_FIRST_LEADING_ONE''@/$(GL_STDC_FIRST_LEADING_ONE)/g' \
-	  -e 's/@''GL_STDC_FIRST_TRAILING_ZERO''@/$(GL_STDC_FIRST_TRAILING_ZERO)/g' \
-	  -e 's/@''GL_STDC_FIRST_TRAILING_ONE''@/$(GL_STDC_FIRST_TRAILING_ONE)/g' \
-	  -e 's/@''GL_STDC_COUNT_ZEROS''@/$(GL_STDC_COUNT_ZEROS)/g' \
-	  -e 's/@''GL_STDC_COUNT_ONES''@/$(GL_STDC_COUNT_ONES)/g' \
-	  -e 's/@''GL_STDC_HAS_SINGLE_BIT''@/$(GL_STDC_HAS_SINGLE_BIT)/g' \
-	  -e 's/@''GL_STDC_BIT_WIDTH''@/$(GL_STDC_BIT_WIDTH)/g' \
-	  -e 's/@''GL_STDC_BIT_FLOOR''@/$(GL_STDC_BIT_FLOOR)/g' \
-	  -e 's/@''GL_STDC_BIT_CEIL''@/$(GL_STDC_BIT_CEIL)/g' \
+	  -e 's/@''HAVE_STDBIT_H''@/$(HAVE_STDBIT_H)/g' \
+	  -e 's/@''GUARD_PREFIX''@/$(GUARD_PREFIX)/g' \
+	  -e 's/@''PRAGMA_SYSTEM_HEADER''@/$(PRAGMA_SYSTEM_HEADER)/g' \
+	  -e 's/@''PRAGMA_COLUMNS''@/$(PRAGMA_COLUMNS)/g' \
+	  -e 's/@''INCLUDE_NEXT''@/$(INCLUDE_NEXT)/g' \
+	  -e 's/@''NEXT_STDBIT_H''@/$(NEXT_STDBIT_H)/g' \
+	  -e 's/@''GNULIB_STDC_LEADING_ZEROS''@/$(GL_GNULIB_STDC_LEADING_ZEROS)/g' \
+	  -e 's/@''GNULIB_STDC_LEADING_ONES''@/$(GL_GNULIB_STDC_LEADING_ONES)/g' \
+	  -e 's/@''GNULIB_STDC_TRAILING_ZEROS''@/$(GL_GNULIB_STDC_TRAILING_ZEROS)/g' \
+	  -e 's/@''GNULIB_STDC_TRAILING_ONES''@/$(GL_GNULIB_STDC_TRAILING_ONES)/g' \
+	  -e 's/@''GNULIB_STDC_FIRST_LEADING_ZERO''@/$(GL_GNULIB_STDC_FIRST_LEADING_ZERO)/g' \
+	  -e 's/@''GNULIB_STDC_FIRST_LEADING_ONE''@/$(GL_GNULIB_STDC_FIRST_LEADING_ONE)/g' \
+	  -e 's/@''GNULIB_STDC_FIRST_TRAILING_ZERO''@/$(GL_GNULIB_STDC_FIRST_TRAILING_ZERO)/g' \
+	  -e 's/@''GNULIB_STDC_FIRST_TRAILING_ONE''@/$(GL_GNULIB_STDC_FIRST_TRAILING_ONE)/g' \
+	  -e 's/@''GNULIB_STDC_COUNT_ZEROS''@/$(GL_GNULIB_STDC_COUNT_ZEROS)/g' \
+	  -e 's/@''GNULIB_STDC_COUNT_ONES''@/$(GL_GNULIB_STDC_COUNT_ONES)/g' \
+	  -e 's/@''GNULIB_STDC_HAS_SINGLE_BIT''@/$(GL_GNULIB_STDC_HAS_SINGLE_BIT)/g' \
+	  -e 's/@''GNULIB_STDC_BIT_WIDTH''@/$(GL_GNULIB_STDC_BIT_WIDTH)/g' \
+	  -e 's/@''GNULIB_STDC_BIT_FLOOR''@/$(GL_GNULIB_STDC_BIT_FLOOR)/g' \
+	  -e 's/@''GNULIB_STDC_BIT_CEIL''@/$(GL_GNULIB_STDC_BIT_CEIL)/g' \
+	  -e 's/@''GNULIB_STDC_ROTATE_LEFT''@/$(GL_GNULIB_STDC_ROTATE_LEFT)/g' \
+	  -e 's/@''GNULIB_STDC_ROTATE_RIGHT''@/$(GL_GNULIB_STDC_ROTATE_RIGHT)/g' \
+	  -e 's/@''GNULIB_STDC_MEMREVERSE8''@/$(GL_GNULIB_STDC_MEMREVERSE8)/g' \
+	  -e 's/@''GNULIB_STDC_MEMREVERSE8U''@/$(GL_GNULIB_STDC_MEMREVERSE8U)/g' \
+	  -e 's/@''GNULIB_STDC_LOAD8_ALIGNED''@/$(GL_GNULIB_STDC_LOAD8_ALIGNED)/g' \
+	  -e 's/@''GNULIB_STDC_LOAD8''@/$(GL_GNULIB_STDC_LOAD8)/g' \
+	  -e 's/@''GNULIB_STDC_STORE8_ALIGNED''@/$(GL_GNULIB_STDC_STORE8_ALIGNED)/g' \
+	  -e 's/@''GNULIB_STDC_STORE8''@/$(GL_GNULIB_STDC_STORE8)/g' \
 	  $(srcdir)/stdbit.in.h > $@-t
 	$(AM_V_at)mv $@-t $@
-libgnu_a_SOURCES += stdbit.c
 else
 stdbit.h: $(top_builddir)/config.status
 	rm -f $@
@ -3230,7 +3261,8 @@ endif
 ## begin gnulib module stdc_bit_width
 ifeq (,$(OMIT_GNULIB_MODULE_stdc_bit_width))

-ifneq (,$(GL_GENERATE_STDBIT_H_CONDITION))
+ifneq (,$(GL_HAVE_STDBIT_H_CONDITION))
+else
 libgnu_a_SOURCES += stdc_bit_width.c
 endif

@ -3240,7 +3272,8 @@ endif
 ## begin gnulib module stdc_count_ones
 ifeq (,$(OMIT_GNULIB_MODULE_stdc_count_ones))

-ifneq (,$(GL_GENERATE_STDBIT_H_CONDITION))
+ifneq (,$(GL_HAVE_STDBIT_H_CONDITION))
+else
 libgnu_a_SOURCES += stdc_count_ones.c
 endif

@ -3250,17 +3283,31 @@ endif
 ## begin gnulib module stdc_leading_zeros
 ifeq (,$(OMIT_GNULIB_MODULE_stdc_leading_zeros))

-ifneq (,$(GL_GENERATE_STDBIT_H_CONDITION))
+ifneq (,$(GL_HAVE_STDBIT_H_CONDITION))
+else
 libgnu_a_SOURCES += stdc_leading_zeros.c
 endif

 endif
 ## end   gnulib module stdc_leading_zeros

+## begin gnulib module stdc_memreverse8u
+ifeq (,$(OMIT_GNULIB_MODULE_stdc_memreverse8u))
+
+ifneq (,$(gl_GNULIB_ENABLED_stdc_memreverse8u_CONDITION))
+ifneq (,$(GL_GENERATE_STDBIT_H_CONDITION))
+libgnu_a_SOURCES += stdc_memreverse8u.c
+endif
+
+endif
+endif
+## end   gnulib module stdc_memreverse8u
+
 ## begin gnulib module stdc_trailing_zeros
 ifeq (,$(OMIT_GNULIB_MODULE_stdc_trailing_zeros))

-ifneq (,$(GL_GENERATE_STDBIT_H_CONDITION))
+ifneq (,$(GL_HAVE_STDBIT_H_CONDITION))
+else
 libgnu_a_SOURCES += stdc_trailing_zeros.c
 endif

@ -3299,6 +3346,36 @@ EXTRA_DIST += intprops-internal.h stdckdint.in.h
 endif
 ## end   gnulib module stdckdint-h

+## begin gnulib module stdcountof-h
+ifeq (,$(OMIT_GNULIB_MODULE_stdcountof-h))
+
+BUILT_SOURCES += $(STDCOUNTOF_H)
+
+# We need the following in order to create <stdcountof.h> when the system
+# doesn't have one that works with the given compiler.
+ifneq (,$(GL_GENERATE_STDCOUNTOF_H_CONDITION))
+stdcountof.h: stdcountof.in.h $(top_builddir)/config.status
+	$(gl_V_at)$(SED_HEADER_STDOUT) \
+	      -e 's|@''GUARD_PREFIX''@|GL|g' \
+	      -e 's/@''HAVE_STDCOUNTOF_H''@/$(HAVE_STDCOUNTOF_H)/g' \
+	      -e 's/@''CXX_HAVE_STDCOUNTOF_H''@/$(CXX_HAVE_STDCOUNTOF_H)/g' \
+	      -e 's|@''INCLUDE_NEXT''@|$(INCLUDE_NEXT)|g' \
+	      -e 's|@''PRAGMA_SYSTEM_HEADER''@|@PRAGMA_SYSTEM_HEADER@|g' \
+	      -e 's|@''PRAGMA_COLUMNS''@|@PRAGMA_COLUMNS@|g' \
+	      -e 's|@''NEXT_STDCOUNTOF_H''@|$(NEXT_STDCOUNTOF_H)|g' \
+	      $(srcdir)/stdcountof.in.h > $@-t
+	$(AM_V_at)mv $@-t $@
+else
+stdcountof.h: $(top_builddir)/config.status
+	rm -f $@
+endif
+MOSTLYCLEANFILES += stdcountof.h stdcountof.h-t
+
+EXTRA_DIST += stdcountof.in.h
+
+endif
+## end   gnulib module stdcountof-h
+
 ## begin gnulib module stddef-h
 ifeq (,$(OMIT_GNULIB_MODULE_stddef-h))

@ -3445,6 +3522,7 @@ stdio.h: stdio.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H)
 	      -e 's/@''GNULIB_STDIO_H_SIGPIPE''@/$(GL_GNULIB_STDIO_H_SIGPIPE)/g' \
 	      -e 's/@''GNULIB_SZPRINTF''@/$(GL_GNULIB_SZPRINTF)/g' \
 	      -e 's/@''GNULIB_TMPFILE''@/$(GL_GNULIB_TMPFILE)/g' \
+	      -e 's/@''GNULIB_VAPRINTF''@/$(GL_GNULIB_VAPRINTF)/g' \
 	      -e 's/@''GNULIB_VASPRINTF''@/$(GL_GNULIB_VASPRINTF)/g' \
 	      -e 's/@''GNULIB_VASZPRINTF''@/$(GL_GNULIB_VASZPRINTF)/g' \
 	      -e 's/@''GNULIB_VDPRINTF''@/$(GL_GNULIB_VDPRINTF)/g' \
@ -3468,6 +3546,7 @@ stdio.h: stdio.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H)
 	      -e 's/@''GNULIB_MDA_GETW''@/$(GL_GNULIB_MDA_GETW)/g' \
 	      -e 's/@''GNULIB_MDA_PUTW''@/$(GL_GNULIB_MDA_PUTW)/g' \
 	      -e 's/@''GNULIB_MDA_TEMPNAM''@/$(GL_GNULIB_MDA_TEMPNAM)/g' \
+	      -e 's/@''GNULIB_FREE_POSIX''@/$(GL_GNULIB_FREE_POSIX)/g' \
 	      < $(srcdir)/stdio.in.h > $@-t1
 	$(AM_V_at)sed \
 	      -e 's|@''HAVE_DECL_FCLOSEALL''@|$(HAVE_DECL_FCLOSEALL)|g' \
@ -3499,6 +3578,7 @@ stdio.h: stdio.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H)
 	      -e 's|@''REPLACE_FOPEN_FOR_FOPEN_GNU''@|$(REPLACE_FOPEN_FOR_FOPEN_GNU)|g' \
 	      -e 's|@''REPLACE_FPRINTF''@|$(REPLACE_FPRINTF)|g' \
 	      -e 's|@''REPLACE_FPURGE''@|$(REPLACE_FPURGE)|g' \
+	      -e 's|@''REPLACE_FREE''@|$(REPLACE_FREE)|g' \
 	      -e 's|@''REPLACE_FREOPEN''@|$(REPLACE_FREOPEN)|g' \
 	      -e 's|@''REPLACE_FSEEK''@|$(REPLACE_FSEEK)|g' \
 	      -e 's|@''REPLACE_FSEEKO''@|$(REPLACE_FSEEKO)|g' \
--- a/lib/idx.h
+++ b/lib/idx.h
@ -19,11 +19,17 @@
 #ifndef _IDX_H
 #define _IDX_H

-/* Get ptrdiff_t.  */
-#include <stddef.h>
+#ifndef __PTRDIFF_TYPE__
+# include <stddef.h>
+#endif

-/* Get PTRDIFF_MAX.  */
-#include <stdint.h>
+/* IDX_MAX is the maximum value of an idx_t.  */
+#ifdef __PTRDIFF_MAX__
+# define IDX_MAX __PTRDIFF_MAX__
+#else
+# include <stdint.h>
+# define IDX_MAX PTRDIFF_MAX
+#endif

 /* The type 'idx_t' holds an (array) index or an (object) size.
   Its implementation promotes to a signed integer type,
@ -127,10 +133,12 @@ extern "C" {
 /* Use the signed type 'ptrdiff_t'.  */
 /* Note: ISO C does not mandate that 'size_t' and 'ptrdiff_t' have the same
   size, but it is so on all platforms we have seen since 1990.  */
+#ifdef __PTRDIFF_TYPE__
+typedef __PTRDIFF_TYPE__ idx_t;
+#else
+/* <stddef.h> already included above.  */
 typedef ptrdiff_t idx_t;
-
-/* IDX_MAX is the maximum value of an idx_t.  */
-#define IDX_MAX PTRDIFF_MAX
+#endif

 /* So far no need has been found for an IDX_WIDTH macro.
   Perhaps there should be another macro IDX_VALUE_BITS that does not
--- a/lib/intprops-internal.h
+++ b/lib/intprops-internal.h
@ -25,6 +25,23 @@
 # pragma GCC diagnostic ignored "-Wtype-limits"
 #endif

+/* Nonzero if this compiler has GCC bug 68193 or Clang bug 25764.  See:
+   https://gcc.gnu.org/PR68193
+   https://github.com/llvm/llvm-project/issues/25764
+   For now, assume GCC < 14 and all Clang versions generate bogus
+   warnings for _Generic.  This matters only for compilers that
+   lack relevant builtins.  */
+#if (__GNUC__ && __GNUC__ < 14) || defined __clang__
+# define _GL__GENERIC_BOGUS 1
+#else
+# define _GL__GENERIC_BOGUS 0
+#endif
+
+/* Suppress -Wuseless-cast for, e.g., gcc-14 -std=gnu99.  */
+#if __STDC_VERSION__ < 201112 && 14 <= __GNUC__
+# pragma GCC diagnostic ignored "-Wuseless-cast"
+#endif
+
 /* Return a value with the common real type of E and V and the value of V.
   Do not evaluate E.  */
 #define _GL_INT_CONVERT(e, v) ((1 ? 0 : (e)) + (v))
@ -32,8 +49,20 @@
 /* The extra casts in the following macros work around compiler bugs,
   e.g., in Cray C 5.0.3.0.  */

-/* True if the real type T is signed.  */
-#define _GL_TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
+/* True if the standard integer or standard real type T is signed.  */
+#if (__STDC_VERSION__ < 201112 || (defined _MSC_VER && _MSC_VER < 1944) \
+     || _GL__GENERIC_BOGUS)
+# define _GL_TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
+#else
+/* Pacify -Wuseless-cast, but do not default to the simpler expression;
+   see <https://gcc.gnu.org/PR125261>.  */
+# define _GL_TYPE_SIGNED(t) \
+   (_Generic ((t) {0}, \
+              bool: 0, char: CHAR_MIN < 0, signed char: 1, unsigned char: 0, \
+              short int: 1, unsigned short int: 0, int: 1, unsigned int: 0, \
+              long int: 1, unsigned long int: 0, long long int: 1, unsigned long long int: 0, \
+              float: 1, double: 1, long double: 1))
+#endif

 /* Return 1 if the real expression E, after promotion, has a
   signed or floating type.  Do not evaluate E.  */
@ -179,18 +208,6 @@
   _GL_INT_OP_WRAPV (a, b, r, *, _GL_INT_MULTIPLY_RANGE_OVERFLOW)
 #endif

-/* Nonzero if this compiler has GCC bug 68193 or Clang bug 25764.  See:
-   https://gcc.gnu.org/PR68193
-   https://github.com/llvm/llvm-project/issues/25764
-   For now, assume GCC < 14 and all Clang versions generate bogus
-   warnings for _Generic.  This matters only for compilers that
-   lack relevant builtins.  */
-#if (__GNUC__ && __GNUC__ < 14) || defined __clang__
-# define _GL__GENERIC_BOGUS 1
-#else
-# define _GL__GENERIC_BOGUS 0
-#endif
-
 /* Store the low-order bits of A <op> B into *R, where OP specifies
   the operation and OVERFLOW the overflow predicate.  Return 1 if the
   result overflows.  Arguments should not have side effects,
@ -304,15 +321,15 @@
   ? (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a, b, op, ut, t), 1) \
   : (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a, b, op, ut, t), 0))

-/* Return 1 if the integer expressions A - B and -A would overflow,
-   respectively.  Arguments should not have side effects,
+/* Return 1 if the integer expression -A would overflow.
+   Arguments should not have side effects,
   and can be any signed integer type other than char, bool, a
   bit-precise integer type, or an enumeration type.
   These macros are tuned for their last input argument being a constant.  */

 #if _GL_HAS_BUILTIN_OVERFLOW_P
 # define _GL_INT_NEGATE_OVERFLOW(a) \
-   __builtin_sub_overflow_p (0, a, (__typeof__ (- (a))) 0)
+   __builtin_sub_overflow_p (0, a, _GL_INT_CONVERT (- (a), 0))
 #else
 # define _GL_INT_NEGATE_OVERFLOW(a) \
   _GL_INT_NEGATE_RANGE_OVERFLOW (a, _GL_INT_MINIMUM (a), _GL_INT_MAXIMUM (a))
--- a/lib/intprops.h
+++ b/lib/intprops.h
@ -25,9 +25,21 @@

 /* True if the arithmetic type T is an integer type.  bool counts as
   an integer.  */
-#define TYPE_IS_INTEGER(t) ((t) 1.5 == 1)
+#if (__STDC_VERSION__ < 201112 || (defined _MSC_VER && _MSC_VER < 1944) \
+     || _GL__GENERIC_BOGUS)
+# define TYPE_IS_INTEGER(t) ((t) 1.5 == 1)
+#else
+/* Pacify -Wuseless-cast and do not default to the simpler expression;
+   see <https://gcc.gnu.org/PR125261>.  */
+# define TYPE_IS_INTEGER(t) \
+    (_Generic ((t) {0}, \
+               bool: 1, char: 1, signed char: 1, unsigned char: 1, \
+               short int: 1, unsigned short int: 1, int: 1, unsigned int: 1, \
+               long int: 1, unsigned long int: 1, long long int: 1, unsigned long long int: 1, \
+               float: 0, double: 0, long double: 0))
+#endif

-/* True if the real type T is signed.  */
+/* True if the standard integer or standard real type T is signed.  */
 #define TYPE_SIGNED(t) _GL_TYPE_SIGNED (t)

 /* Return 1 if the real expression E, after promotion, has a
@ -50,12 +62,34 @@
   Padding bits are not supported; this is checked at compile-time below.  */
 #define TYPE_WIDTH(t) _GL_TYPE_WIDTH (t)

-/* The maximum and minimum values for the integer type T.  */
-#define TYPE_MINIMUM(t) ((t) ~ TYPE_MAXIMUM (t))
-#define TYPE_MAXIMUM(t)                                                 \
-  ((t) (! TYPE_SIGNED (t)                                               \
-        ? (t) -1                                                        \
-        : ((((t) 1 << (TYPE_WIDTH (t) - 2)) - 1) * 2 + 1)))
+/* The maximum and minimum values for the standard integer type T.  */
+#if (__STDC_VERSION__ < 201112 || (defined _MSC_VER && _MSC_VER < 1944) \
+     || _GL__GENERIC_BOGUS)
+# define TYPE_MINIMUM(t) ((t) ~ TYPE_MAXIMUM (t))
+# define TYPE_MAXIMUM(t)                                                \
+   ((t) (! TYPE_SIGNED (t)                                              \
+         ? (t) -1                                                       \
+         : ((((t) 1 << (TYPE_WIDTH (t) - 2)) - 1) * 2 + 1)))
+#else
+/* Pacify -Wuseless-cast and do not default to the simpler expressions;
+   see <https://gcc.gnu.org/PR125261>.  */
+# define TYPE_MINIMUM(t) \
+   (_Generic ((t) {0}, \
+              bool: (bool) 0, char: (char) CHAR_MIN, \
+              signed char: (signed char) SCHAR_MIN, unsigned char: (unsigned char) 0, \
+              short int: (short int) SHRT_MIN, unsigned short int: (unsigned short int) 0, \
+              int: INT_MIN, unsigned int: 0u, \
+              long int: LONG_MIN, unsigned long int: 0ul, \
+              long long int: LLONG_MIN, unsigned long long int: 0ull))
+# define TYPE_MAXIMUM(t) \
+   (_Generic ((t) {0}, \
+              bool: (bool) 1, char: (char) CHAR_MAX, \
+              signed char: (signed char) SCHAR_MAX, unsigned char: (unsigned char) -1, \
+              short int: (short int) SHRT_MAX, unsigned short int: (unsigned short int) -1, \
+              int: INT_MAX, unsigned int: -1u, \
+              long int: LONG_MAX, unsigned long int: -1ul, \
+              long long int: LLONG_MAX, unsigned long long int: -1ull))
+#endif

 /* Bound on length of the string representing an unsigned integer
   value representable in B bits.  log10 (2.0) < 146/485.  The
@ -184,11 +218,11 @@
   that the result (e.g., A + B) has that type.  */
 #if _GL_HAS_BUILTIN_OVERFLOW_P
 # define _GL_ADD_OVERFLOW(a, b, min, max)                               \
-   __builtin_add_overflow_p (a, b, (__typeof__ ((a) + (b))) 0)
+   __builtin_add_overflow_p (a, b, _GL_INT_CONVERT ((a) + (b), 0))
 # define _GL_SUBTRACT_OVERFLOW(a, b, min, max)                          \
-   __builtin_sub_overflow_p (a, b, (__typeof__ ((a) - (b))) 0)
+   __builtin_sub_overflow_p (a, b, _GL_INT_CONVERT ((a) - (b), 0))
 # define _GL_MULTIPLY_OVERFLOW(a, b, min, max)                          \
-   __builtin_mul_overflow_p (a, b, (__typeof__ ((a) * (b))) 0)
+   __builtin_mul_overflow_p (a, b, _GL_INT_CONVERT ((a) * (b), 0))
 #else
 # define _GL_ADD_OVERFLOW(a, b, min, max)                                \
   ((min) < 0 ? INT_ADD_RANGE_OVERFLOW (a, b, min, max)                  \
--- a/lib/nproc.c
+++ b/lib/nproc.c
@ -25,6 +25,7 @@
 #if HAVE_SETMNTENT
 # include <mntent.h>
 #endif
+#include <stdcountof.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
@ -61,8 +62,6 @@

 #include "minmax.h"

-#define ARRAY_SIZE(a) (sizeof (a) / sizeof ((a)[0]))
-
 #define NPROC_MINIMUM 1

 /* Return the number of processors available to the current process, based
@ -335,9 +334,9 @@ num_processors_available (enum nproc_query query)
 # endif
      { CTL_HW, HW_NCPU }
    };
-    for (int i = 0; i < ARRAY_SIZE (mib); i++)
+    for (int i = 0; i < countof (mib); i++)
      {
-        if (sysctl (mib[i], ARRAY_SIZE (mib[i]), &nprocs, &len, NULL, 0) == 0
+        if (sysctl (mib[i], countof (mib[i]), &nprocs, &len, NULL, 0) == 0
            && len == sizeof (nprocs)
            && 0 < nprocs)
          return nprocs;
--- a/lib/pthread_sigmask.c
+++ b/lib/pthread_sigmask.c
@ -19,19 +19,22 @@
 /* Specification.  */
 #include <signal.h>

-#include <errno.h>
-#include <stddef.h>
+/* The native Windows implementation is defined in sigprocmask.c.  */
+#if !(defined _WIN32 && !defined __CYGWIN__)

-#if PTHREAD_SIGMASK_INEFFECTIVE
-# include <string.h>
-#endif
+# include <errno.h>
+# include <stddef.h>
+
+# if PTHREAD_SIGMASK_INEFFECTIVE
+#  include <string.h>
+# endif

 int
 pthread_sigmask (int how, const sigset_t *new_mask, sigset_t *old_mask)
-#undef pthread_sigmask
+# undef pthread_sigmask
 {
-#if HAVE_PTHREAD_SIGMASK
-# if PTHREAD_SIGMASK_INEFFECTIVE
+# if HAVE_PTHREAD_SIGMASK && !PTHREAD_SIGMASK_NOT_IN_LIBC
+#  if PTHREAD_SIGMASK_INEFFECTIVE
  sigset_t omask;
  sigset_t *old_mask_ptr = &omask;
  sigemptyset (&omask);
@ -40,13 +43,13 @@ pthread_sigmask (int how, const sigset_t *new_mask, sigset_t *old_mask)
  sigaddset (&omask, SIGILL);
  sigset_t omask_copy;
  memcpy (&omask_copy, &omask, sizeof omask);
-# else
+#  else
  sigset_t *old_mask_ptr = old_mask;
-# endif
+#  endif

  int ret = pthread_sigmask (how, new_mask, old_mask_ptr);

-# if PTHREAD_SIGMASK_INEFFECTIVE
+#  if PTHREAD_SIGMASK_INEFFECTIVE
  if (ret == 0)
    {
      /* Detect whether pthread_sigmask is currently ineffective.
@ -64,14 +67,18 @@ pthread_sigmask (int how, const sigset_t *new_mask, sigset_t *old_mask)
      if (old_mask)
        memcpy (old_mask, &omask, sizeof omask);
    }
-# endif
-# if PTHREAD_SIGMASK_FAILS_WITH_ERRNO
+#  endif
+#  if PTHREAD_SIGMASK_FAILS_WITH_ERRNO
  if (ret == -1)
    return errno;
-# endif
+#  endif
  return ret;
-#else
+# else
  int ret = sigprocmask (how, new_mask, old_mask);
-  return (ret < 0 ? errno : 0);
-#endif
+  /* Test for ret != 0, not ret < 0, as a workaround against NetBSD bug
+     <https://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=57213>.  */
+  return (ret != 0 ? errno : 0);
+# endif
 }
+
+#endif
--- a/lib/readutmp.h
+++ b/lib/readutmp.h
@ -330,7 +330,7 @@ char *extract_trimmed_name (const STRUCT_UTMP *ut)
   If OPTIONS & READ_UTMP_NO_BOOT_TIME is nonzero, omit the boot time
   entries.

-   This function is not multithread-safe, since on many platforms it
+   This function is not thread-safe, since on many platforms it
   invokes the functions setutxent, getutxent, endutxent.  These
   functions are needed because they may lock FILE (so that we don't
   read garbage when a concurrent process writes to FILE), but their
--- a/lib/regcomp.c
+++ b/lib/regcomp.c
@ -21,6 +21,12 @@
 # include <locale/weight.h>
 #endif

+/* The localeinfo-related code fixes glibc bug 20381.
+   Someday this fix should be merged into glibc.  */
+#if !defined _LIBC && !defined _REGEX_AVOID_UCHAR_H
+# include "localeinfo.h"
+#endif
+
 static reg_errcode_t re_compile_internal (regex_t *preg, const char * pattern,
 					  size_t length, reg_syntax_t syntax);
 static void re_compile_fastmap_iter (regex_t *bufp,
@ -267,11 +273,31 @@ re_compile_fastmap (struct re_pattern_buffer *bufp)
 weak_alias (__re_compile_fastmap, re_compile_fastmap)

 static __always_inline void
-re_set_fastmap (char *fastmap, bool icase, int ch)
+re_set_fastmap (char *fastmap, unsigned char ch)
 {
  fastmap[ch] = 1;
-  if (icase)
-    fastmap[tolower (ch)] = 1;
+}
+
+/* Record in FASTMAP the initial byte of the representations of all
+   characters that match WC ignoring case, other than WC itself.
+   Use MBS as a scratch state.  */
+
+static void
+re_set_fastmap_icase (char *fastmap, wchar_t wc, mbstate_t *mbs)
+{
+#if defined _LIBC || defined _REGEX_AVOID_UCHAR_H
+  wchar_t folded[1] = {__towlower (wc)};
+  int nfolded = folded[0] != wc;
+#else
+  wchar_t folded[CASE_FOLDED_BUFSIZE];
+  int nfolded = case_folded_counterparts (wc, folded);
+#endif
+  for (int i = 0; i < nfolded; i++)
+    {
+      char buf[MB_LEN_MAX];
+      if (__wcrtomb (buf, folded[i], mbs) != (size_t) -1)
+	re_set_fastmap (fastmap, buf[0]);
+    }
 }

 /* Helper function for re_compile_fastmap.
@ -283,7 +309,6 @@ re_compile_fastmap_iter (regex_t *bufp, const re_dfastate_t *init_state,
 {
  re_dfa_t *dfa = bufp->buffer;
  Idx node_cnt;
-  bool icase = (dfa->mb_cur_max == 1 && (bufp->syntax & RE_ICASE));
  for (node_cnt = 0; node_cnt < init_state->nodes.nelem; ++node_cnt)
    {
      Idx node = init_state->nodes.elems[node_cnt];
@ -291,8 +316,8 @@ re_compile_fastmap_iter (regex_t *bufp, const re_dfastate_t *init_state,

      if (type == CHARACTER)
 	{
-	  re_set_fastmap (fastmap, icase, dfa->nodes[node].opr.c);
-	  if ((bufp->syntax & RE_ICASE) && dfa->mb_cur_max > 1)
+	  re_set_fastmap (fastmap, dfa->nodes[node].opr.c);
+	  if (bufp->syntax & RE_ICASE)
 	    {
 	      unsigned char buf[MB_LEN_MAX];
 	      unsigned char *p;
@ -307,10 +332,8 @@ re_compile_fastmap_iter (regex_t *bufp, const re_dfastate_t *init_state,
 		*p++ = dfa->nodes[node].opr.c;
 	      memset (&state, '\0', sizeof (state));
 	      if (__mbrtowc (&wc, (const char *) buf, p - buf,
-			     &state) == p - buf
-		  && (__wcrtomb ((char *) buf, __towlower (wc), &state)
-		      != (size_t) -1))
-		re_set_fastmap (fastmap, false, buf[0]);
+			     &state) == p - buf)
+		re_set_fastmap_icase (fastmap, wc, &state);
 	    }
 	}
      else if (type == SIMPLE_BRACKET)
@ -322,7 +345,7 @@ re_compile_fastmap_iter (regex_t *bufp, const re_dfastate_t *init_state,
 	      bitset_word_t w = dfa->nodes[node].opr.sbcset[i];
 	      for (j = 0; j < BITSET_WORD_BITS; ++j, ++ch)
 		if (w & ((bitset_word_t) 1 << j))
-		  re_set_fastmap (fastmap, icase, ch);
+		  re_set_fastmap (fastmap, ch);
 	    }
 	}
      else if (type == COMPLEX_BRACKET)
@ -344,7 +367,7 @@ re_compile_fastmap_iter (regex_t *bufp, const re_dfastate_t *init_state,
 		    _NL_CURRENT (LC_COLLATE, _NL_COLLATE_TABLEMB);
 		  for (i = 0; i < SBC_MAX; ++i)
 		    if (table[i] < 0)
-		      re_set_fastmap (fastmap, icase, i);
+		      re_set_fastmap (fastmap, i);
 		}
 #endif /* _LIBC */

@ -365,7 +388,7 @@ re_compile_fastmap_iter (regex_t *bufp, const re_dfastate_t *init_state,
 		  mbstate_t mbs;
 		  memset (&mbs, 0, sizeof (mbs));
 		  if (__mbrtowc (NULL, (char *) &c, 1, &mbs) == (size_t) -2)
-		    re_set_fastmap (fastmap, false, (int) c);
+		    re_set_fastmap (fastmap, c);
 		}
 	      while (++c != 0);
 	    }
@ -375,17 +398,13 @@ re_compile_fastmap_iter (regex_t *bufp, const re_dfastate_t *init_state,
 	      /* ... Else catch all bytes which can start the mbchars.  */
 	      for (i = 0; i < cset->nmbchars; ++i)
 		{
-		  char buf[256];
+		  char buf[MB_LEN_MAX];
 		  mbstate_t state;
 		  memset (&state, '\0', sizeof (state));
 		  if (__wcrtomb (buf, cset->mbchars[i], &state) != (size_t) -1)
-		    re_set_fastmap (fastmap, icase, *(unsigned char *) buf);
-		  if ((bufp->syntax & RE_ICASE) && dfa->mb_cur_max > 1)
-		    {
-		      if (__wcrtomb (buf, __towlower (cset->mbchars[i]), &state)
-			  != (size_t) -1)
-			re_set_fastmap (fastmap, false, *(unsigned char *) buf);
-		    }
+		    re_set_fastmap (fastmap, buf[0]);
+		  if (bufp->syntax & RE_ICASE)
+		    re_set_fastmap_icase (fastmap, cset->mbchars[i], &state);
 		}
 	    }
 	}
@ -499,7 +518,7 @@ regerror (int errcode, const regex_t *__restrict preg, char *__restrict errbuf,
 {
  const char *msg;
  size_t msg_size;
-  int nerrcodes = sizeof __re_error_msgid_idx / sizeof __re_error_msgid_idx[0];
+  int nerrcodes = countof (__re_error_msgid_idx);

  if (__glibc_unlikely (errcode < 0 || errcode >= nerrcodes))
    /* Only error codes returned by the rest of the code should be passed
--- a/lib/regex.c
+++ b/lib/regex.c
@ -20,6 +20,7 @@
 #define __STDC_WANT_IEC_60559_BFP_EXT__

 #ifndef _LIBC
+# define _GL_USE_STDLIB_ALLOC 1
 # include <libc-config.h>

 # if __GNUC_PREREQ (4, 6)
--- a/lib/regex.h
+++ b/lib/regex.h
@ -645,15 +645,15 @@ extern int re_exec (const char *);
     array_name[restrict]
   use glibc's __restrict_arr if available.
   Otherwise, GCC 3.1 and clang support this syntax (but not in C++ mode).
-   Other ISO C99 compilers support it as well.  */
+   Other ISO C99 compilers support it as well, except for MSVC.  */
 #ifndef _Restrict_arr_
 # ifdef __restrict_arr
 #  define _Restrict_arr_ __restrict_arr
 # else
-#  if ((199901L <= __STDC_VERSION__ \
-         || 3 < __GNUC__ + (1 <= __GNUC_MINOR__) \
-         || __clang_major__ >= 3) \
-        && !defined __cplusplus)
+#  if (((199901L <= __STDC_VERSION__ && !defined _MSC_VER) \
+        || 3 < __GNUC__ + (1 <= __GNUC_MINOR__) \
+        || __clang_major__ >= 3) \
+       && !defined __cplusplus)
 #   define _Restrict_arr_ _Restrict_
 #  else
 #   define _Restrict_arr_
--- a/lib/regex_internal.c
+++ b/lib/regex_internal.c
@ -387,7 +387,7 @@ build_wcs_upper_buffer (re_string_t *pstr)
 	      {
 		size_t mbcdlen;

-		mbcdlen = __wcrtomb ((char *) buf, wcu, &prev_st);
+		mbcdlen = __wcrtomb (buf, wcu, &prev_st);
 		if (__glibc_likely (mbclen == mbcdlen))
 		  memcpy (pstr->mbs + byte_idx, buf, mbclen);
 		else if (mbcdlen != (size_t) -1)
@ -1241,8 +1241,8 @@ re_node_set_merge (re_node_set *dest, const re_node_set *src)
 }

 /* Insert the new element ELEM to the re_node_set* SET.
-   SET should not already have ELEM.
-   Return true if successful.  */
+   SET is not expected to already contain ELEM, but tolerate
+   duplicates as a no-op.  Return true if successful.  */

 static bool
 __attribute_warn_unused_result__
@ -1285,8 +1285,16 @@ re_node_set_insert (re_node_set *set, Idx elem)
  else
    {
      for (idx = set->nelem; set->elems[idx - 1] > elem; idx--)
-	set->elems[idx] = set->elems[idx - 1];
-      DEBUG_ASSERT (set->elems[idx - 1] < elem);
+        {
+          set->elems[idx] = set->elems[idx - 1];
+          /* Although we already guaranteed that idx is at least 2 here,
+             add an assertion to pacify GCC 16.1.1 -Wanalyzer-out-of-bounds
+             when _REGEX_AVOID_UCHAR_H is defined.  */
+          DEBUG_ASSERT (1 < idx);
+        }
+      /* Already in set.  Return early.  */
+      if (__glibc_unlikely (set->elems[idx - 1] == elem))
+	return true;
    }

  /* Insert the new element.  */
--- a/lib/regex_internal.h
+++ b/lib/regex_internal.h
@ -27,9 +27,8 @@

 #include <langinfo.h>
 #include <locale.h>
-#include <wchar.h>
-#include <wctype.h>
 #include <stdckdint.h>
+#include <stdcountof.h>
 #include <stdint.h>

 #ifndef _LIBC
@ -120,22 +119,47 @@
 #define NEWLINE_CHAR '\n'
 #define WIDE_NEWLINE_CHAR L'\n'

-/* Rename to standard API for using out of glibc.  */
+/* Use Gnulib <uchar.h> if outside glibc and not avoided by the app.  */
+#if defined _LIBC || defined _REGEX_AVOID_UCHAR_H
+# include <wchar.h>
+# include <wctype.h>
+#else
+# include <uchar.h>
+# undef wctype_t
+# define wchar_t char32_t
+# define wctype_t c32_type_test_t
+#endif
+
 #ifndef _LIBC
 # undef __wctype
 # undef __iswalnum
 # undef __iswctype
 # undef __towlower
 # undef __towupper
-# define __wctype wctype
-# define __iswalnum iswalnum
-# define __iswctype iswctype
-# define __towlower towlower
-# define __towupper towupper
-# define __btowc btowc
-# define __mbrtowc mbrtowc
-# define __wcrtomb wcrtomb
+# undef __btowc
+# undef __mbrtowc
+# undef __wcrtomb
+# undef __regfree
 # define __regfree regfree
+# ifdef _REGEX_AVOID_UCHAR_H
+#  define __wctype wctype
+#  define __iswalnum iswalnum
+#  define __iswctype iswctype
+#  define __towlower towlower
+#  define __towupper towupper
+#  define __btowc btowc
+#  define __mbrtowc mbrtowc
+#  define __wcrtomb wcrtomb
+# else
+#  define __wctype c32_get_type_test
+#  define __iswalnum c32isalnum
+#  define __iswctype c32_apply_type_test
+#  define __towlower c32tolower
+#  define __towupper c32toupper
+#  define __btowc btoc32
+#  define __mbrtowc mbrtoc32
+#  define __wcrtomb c32rtomb
+# endif
 #endif /* not _LIBC */

 /* Types related to integers.  Unless protected by #ifdef _LIBC, the
@ -171,7 +195,11 @@
   reindenting a lot of regex code that formerly used 'int'.  */
 typedef regoff_t Idx;
 #ifdef _REGEX_LARGE_OFFSETS
-# define IDX_MAX SSIZE_MAX
+# ifdef SSIZE_MAX
+#  define IDX_MAX SSIZE_MAX
+# else
+#  define IDX_MAX ((Idx) ((size_t) -1 / 2))
+# endif
 #else
 # define IDX_MAX INT_MAX
 #endif
@ -435,7 +463,11 @@ typedef struct re_dfa_t re_dfa_t;
 # define MIN(a,b) ((a) < (b) ? (a) : (b))
 #endif

-#define re_malloc(t,n) ((t *) malloc ((n) * sizeof (t)))
+#if defined _LIBC || HAVE_MALLOC_0_NONNULL
+# define re_malloc(t,n) ((t *) malloc ((n) * sizeof (t)))
+#else
+# define re_malloc(t,n) ((t *) malloc ((n) * sizeof (t) + ((n) == 0)))
+#endif
 #define re_realloc(p,t,n) ((t *) realloc (p, (n) * sizeof (t)))
 #define re_free(p) free (p)

@ -772,8 +804,8 @@ __attribute__ ((pure, unused))
 re_string_wchar_at (const re_string_t *pstr, Idx idx)
 {
  if (pstr->mb_cur_max == 1)
-    return (wint_t) pstr->mbs[idx];
-  return (wint_t) pstr->wcs[idx];
+    return pstr->mbs[idx];
+  return pstr->wcs[idx];
 }

 #ifdef _LIBC
--- a/lib/regexec.c
+++ b/lib/regexec.c
@ -627,6 +627,8 @@ re_search_internal (const regex_t *preg, const char *string, Idx length,
  /* We must check the longest matching, if nmatch > 0.  */
  fl_longest_match = (nmatch != 0 || dfa->nbackref);

+  re_dfastate_t **save_state_log = NULL;
+
  err = re_string_allocate (&mctx.input, string, length, dfa->nodes_len + 1,
 			    preg->translate, (preg->syntax & RE_ICASE) != 0,
 			    dfa);
@ -802,11 +804,32 @@ re_search_internal (const regex_t *preg, const char *string, Idx length,
 	      if ((!preg->no_sub && nmatch > 1 && dfa->has_plural_match)
 		  || dfa->nbackref)
 		{
+		  /* Save state_log before pruning, in case set_regs
+		     later fails and we need to retry with a shorter
+		     match.  */
+		  re_free (save_state_log);
+		  save_state_log = NULL;
+		  if (!preg->no_sub && nmatch > 1 && dfa->nbackref)
+		    {
+		      save_state_log
+			= re_malloc (re_dfastate_t *,
+				     mctx.match_last + 1);
+		      if (__glibc_unlikely (save_state_log == NULL))
+			{
+			  err = REG_ESPACE;
+			  goto free_return;
+			}
+		      memcpy (save_state_log, mctx.state_log,
+			      sizeof (re_dfastate_t *)
+			      * (mctx.match_last + 1));
+		    }
 		  err = prune_impossible_nodes (&mctx);
 		  if (err == REG_NOERROR)
 		    break;
 		  if (__glibc_unlikely (err != REG_NOMATCH))
 		    goto free_return;
+		  re_free (save_state_log);
+		  save_state_log = NULL;
 		  match_last = -1;
 		}
 	      else
@ -825,24 +848,79 @@ re_search_internal (const regex_t *preg, const char *string, Idx length,
    {
      Idx reg_idx;

-      /* Initialize registers.  */
-      for (reg_idx = 1; reg_idx < nmatch; ++reg_idx)
-	pmatch[reg_idx].rm_so = pmatch[reg_idx].rm_eo = -1;
-
-      /* Set the points where matching start/end.  */
-      pmatch[0].rm_so = 0;
-      pmatch[0].rm_eo = mctx.match_last;
-      /* FIXME: This function should fail if mctx.match_last exceeds
-	 the maximum possible regoff_t value.  We need a new error
-	 code REG_OVERFLOW.  */
-
-      if (!preg->no_sub && nmatch > 1)
+      /* When set_regs fails for a backref pattern, the structural
+	 match at match_last has no valid register assignment.  Try
+	 shorter match lengths, since a valid shorter match may
+	 exist (e.g., all groups matching empty).  */
+      for (;;)
 	{
+	  /* Initialize registers.  */
+	  for (reg_idx = 1; reg_idx < nmatch; ++reg_idx)
+	    pmatch[reg_idx].rm_so = pmatch[reg_idx].rm_eo = -1;
+	  pmatch[0].rm_so = 0;
+	  pmatch[0].rm_eo = mctx.match_last;
+
+	  if (preg->no_sub || nmatch <= 1)
+	    break;
+
 	  err = set_regs (preg, &mctx, nmatch, pmatch,
 			  dfa->has_plural_match && dfa->nbackref > 0);
+	  if (__glibc_likely (err == REG_NOERROR)
+	      || save_state_log == NULL
+	      || err != REG_NOMATCH)
+	    break;
+
+	  /* set_regs failed; try a shorter match_last.  */
+	  Idx ml = mctx.match_last;
+	  re_free (mctx.state_log);
+	  do
+	    {
+	      --ml;
+	      if (ml < 0)
+		break;
+	    }
+	  while (save_state_log[ml] == NULL
+		 || !save_state_log[ml]->halt
+		 || !check_halt_state_context
+		      (&mctx, save_state_log[ml], ml));
+	  if (ml < 0)
+	    {
+	      err = REG_NOMATCH;
+	      mctx.state_log = save_state_log;
+	      save_state_log = NULL;
+	      break;
+	    }
+	  mctx.state_log
+	    = re_malloc (re_dfastate_t *, ml + 1);
+	  if (__glibc_unlikely (mctx.state_log == NULL))
+	    {
+	      mctx.state_log = save_state_log;
+	      save_state_log = NULL;
+	      err = REG_ESPACE;
+	      break;
+	    }
+	  memcpy (mctx.state_log, save_state_log,
+		  sizeof (re_dfastate_t *) * (ml + 1));
+	  mctx.match_last = ml;
+	  mctx.last_node
+	    = check_halt_state_context
+		(&mctx, save_state_log[ml], ml);
+	  err = prune_impossible_nodes (&mctx);
 	  if (__glibc_unlikely (err != REG_NOERROR))
-	    goto free_return;
+	    {
+	      if (err == REG_NOMATCH)
+		{
+		  re_free (mctx.state_log);
+		  mctx.state_log = save_state_log;
+		  save_state_log = NULL;
+		}
+	      break;
+	    }
 	}
+      re_free (save_state_log);
+      save_state_log = NULL;
+      if (__glibc_unlikely (err != REG_NOERROR))
+	goto free_return;

      /* At last, add the offset to each register, since we slid
 	 the buffers so that we could assume that the matching starts
@ -882,6 +960,7 @@ re_search_internal (const regex_t *preg, const char *string, Idx length,
    }

 free_return:
+  re_free (save_state_log);
  re_free (mctx.state_log);
  if (dfa->nbackref)
    match_ctx_free (&mctx);
@ -934,7 +1013,7 @@ prune_impossible_nodes (re_match_context_t *mctx)
 	      goto free_return;
 	  if (sifted_states[0] != NULL || lim_states[0] != NULL)
 	    break;
-	  do
+	  for (;;)
 	    {
 	      --match_last;
 	      if (match_last < 0)
@ -942,11 +1021,17 @@ prune_impossible_nodes (re_match_context_t *mctx)
 		  ret = REG_NOMATCH;
 		  goto free_return;
 		}
-	    } while (mctx->state_log[match_last] == NULL
-		     || !mctx->state_log[match_last]->halt);
-	  halt_node = check_halt_state_context (mctx,
-						mctx->state_log[match_last],
-						match_last);
+              if (mctx->state_log[match_last] != NULL
+                  && mctx->state_log[match_last]->halt)
+                {
+                  halt_node
+                    = check_halt_state_context (mctx,
+                                                mctx->state_log[match_last],
+                                                match_last);
+                  if (halt_node)
+                    break;
+                }
+	    }
 	}
      ret = merge_state_array (dfa, sifted_states, lim_states,
 			       match_last + 1);
@ -2256,7 +2341,7 @@ merge_state_with_log (reg_errcode_t *err, re_match_context_t *mctx,
      mctx->state_log[cur_idx] = next_state;
      mctx->state_log_top = cur_idx;
    }
-  else if (mctx->state_log[cur_idx] == 0)
+  else if (mctx->state_log[cur_idx] == NULL)
    {
      mctx->state_log[cur_idx] = next_state;
    }
--- a/lib/scratch_buffer.h
+++ b/lib/scratch_buffer.h
@ -102,9 +102,9 @@ extern bool scratch_buffer_set_array_size (struct scratch_buffer *buffer,
 /* The implementation is imported from glibc.  */

 /* Avoid possible conflicts with symbols exported by the GNU libc.  */
-#define __libc_scratch_buffer_grow gl_scratch_buffer_grow
-#define __libc_scratch_buffer_grow_preserve gl_scratch_buffer_grow_preserve
-#define __libc_scratch_buffer_set_array_size gl_scratch_buffer_set_array_size
+#define __libc_scratch_buffer_grow _gl_scratch_buffer_grow
+#define __libc_scratch_buffer_grow_preserve _gl_scratch_buffer_grow_preserve
+#define __libc_scratch_buffer_set_array_size _gl_scratch_buffer_set_array_size

 #ifndef _GL_LIKELY
 /* Rely on __builtin_expect, as provided by the module 'builtin-expect'.  */
--- a/lib/set-permissions.c
+++ b/lib/set-permissions.c
@ -21,6 +21,8 @@

 #include "acl.h"

+#include <stdcountof.h>
+
 #include "acl-internal.h"
 #include "minmax.h"

@ -251,11 +253,9 @@ set_acls_from_mode (const char *name, int desc, mode_t mode, bool *must_chmod)

    int ret;
    if (desc != -1)
-      ret = facl (desc, SETACL,
-                  sizeof (entries) / sizeof (aclent_t), entries);
+      ret = facl (desc, SETACL, countof (entries), entries);
    else
-      ret = acl (name, SETACL,
-                 sizeof (entries) / sizeof (aclent_t), entries);
+      ret = acl (name, SETACL, countof (entries), entries);
    if (ret < 0)
      {
        if (errno == ENOSYS || errno == EOPNOTSUPP)
--- a/lib/sha1.c
+++ b/lib/sha1.c
@ -240,7 +240,7 @@ sha1_process_block (void const *restrict buffer, size_t len,
  ctx->total[0] += lolen;
  ctx->total[1] += (len >> 31 >> 1) + (ctx->total[0] < lolen);

-#define rol(x, n) (((x) << (n)) | ((uint32_t) (x) >> (32 - (n))))
+#define rol(x, n) (((x) << (n)) | ((uint32_t) {(x)} >> (32 - (n))))

 #define M(I) ( tm =   x[I&0x0f] ^ x[(I-14)&0x0f] \
                    ^ x[(I-8)&0x0f] ^ x[(I-3)&0x0f] \
--- a/lib/sig2str.c
+++ b/lib/sig2str.c
@ -23,6 +23,7 @@
 #include <signal.h>

 #include <limits.h>
+#include <stdcountof.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
@ -260,8 +261,6 @@ static struct numname { int num; char const name[8]; } numname_table[] =
    { 0, "EXIT" }
  };

-#define NUMNAME_ENTRIES (sizeof numname_table / sizeof numname_table[0])
-
 /* ISDIGIT differs from isdigit, as follows:
   - Its arg may be any int or unsigned int; it need not be an unsigned char
     or EOF.
@ -286,7 +285,7 @@ str2signum (char const *signame)
    }
  else
    {
-      for (unsigned int i = 0; i < NUMNAME_ENTRIES; i++)
+      for (int i = 0; i < countof (numname_table); i++)
        if (streq (numname_table[i].name, signame))
          return numname_table[i].num;

@ -331,7 +330,7 @@ str2sig (char const *signame, int *signum)
 int
 sig2str (int signum, char *signame)
 {
-  for (unsigned int i = 0; i < NUMNAME_ENTRIES; i++)
+  for (int i = 0; i < countof (numname_table); i++)
    if (numname_table[i].num == signum)
      {
        strcpy (signame, numname_table[i].name);
--- a/lib/signal.in.h
+++ b/lib/signal.in.h
@ -20,6 +20,12 @@
 #endif
@PRAGMA_COLUMNS@

+/* Deactivate the mingw <pthread_signal.h>, that provides an unusable definition
+   of pthread_sigmask().  We need to do this before including <signal.h>.  */
+#ifndef WIN_PTHREADS_SIGNAL_H
+#define WIN_PTHREADS_SIGNAL_H
+#endif
+
 #if defined __need_sig_atomic_t || defined __need_sigset_t || defined _@GUARD_PREFIX@_ALREADY_INCLUDING_SIGNAL_H || (defined _SIGNAL_H && !defined __SIZEOF_PTHREAD_MUTEX_T)
 /* Special invocation convention:
   - Inside glibc header files.
@ -68,12 +74,13 @@

 /* Mac OS X 10.3, FreeBSD < 8.0, OpenBSD < 5.1, Solaris 2.6, Android,
   OS/2 kLIBC declare pthread_sigmask in <pthread.h>, not in <signal.h>.
-   But avoid namespace pollution on glibc systems.*/
+   But avoid namespace pollution on glibc systems.  */
 #if (@GNULIB_PTHREAD_SIGMASK@ || defined GNULIB_POSIXCHECK) \
    && ((defined __APPLE__ && defined __MACH__) \
        || (defined __FreeBSD__ && __FreeBSD__ < 8) \
        || (defined __OpenBSD__ && OpenBSD < 201205) \
-        || defined __sun || defined __ANDROID__ \
+        || (defined __sun && !defined __cplusplus) \
+        || defined __ANDROID__ \
        || defined __KLIBC__) \
    && ! defined __GLIBC__
 # include <pthread.h>
--- a/lib/stat-time.h
+++ b/lib/stat-time.h
@ -28,6 +28,7 @@

 #include <errno.h>
 #include <stdckdint.h>
+#include <stdcountof.h>
 #include <stddef.h>
 #include <sys/stat.h>
 #include <time.h>
@ -232,7 +233,7 @@ stat_time_normalize (int result, _GL_UNUSED struct stat *st)
      short int const ts_off[] = { STAT_TIMESPEC_OFFSETOF (st_atim),
                                   STAT_TIMESPEC_OFFSETOF (st_mtim),
                                   STAT_TIMESPEC_OFFSETOF (st_ctim) };
-      for (int i = 0; i < sizeof ts_off / sizeof *ts_off; i++)
+      for (int i = 0; i < countof (ts_off); i++)
        {
          struct timespec *ts = (struct timespec *) ((char *) st + ts_off[i]);
          long int q = ts->tv_nsec / timespec_hz;
--- a/lib/stdbit.in.h
+++ b/lib/stdbit.in.h
--- a/lib/stdc_count_ones.c
+++ b/lib/stdc_count_ones.c
@ -19,5 +19,5 @@
 #include <stdbit.h>

 #if 1500 <= _MSC_VER && (defined _M_IX86 || defined _M_X64)
-signed char __gl_stdbit_popcount_support;
+signed char _gl_stdbit_popcount_support;
 #endif
--- a/lib/stdc_memreverse8u.c
+++ b/lib/stdc_memreverse8u.c
@ -0,0 +1,19 @@
+/* stdc_memreverse8u* functions.
+   Copyright (C) 2026 Free Software Foundation, Inc.
+
+   This file 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.
+
+   This file 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 this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+#define _GL_STDC_MEMREVERSE8U_INLINE _GL_EXTERN_INLINE
+#include <config.h>
+#include <stdbit.h>
--- a/lib/stdcountof.in.h
+++ b/lib/stdcountof.in.h
@ -0,0 +1,124 @@
+/* Copyright 2025-2026 Free Software Foundation, Inc.
+
+   This program 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.
+
+   This program 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 this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2025.  */
+
+#ifndef _@GUARD_PREFIX@_STDCOUNTOF_H
+
+#if __GNUC__ >= 3
+@PRAGMA_SYSTEM_HEADER@
+#endif
+@PRAGMA_COLUMNS@
+
+/* The include_next requires a split double-inclusion guard.  */
+#if (defined __cplusplus ? @CXX_HAVE_STDCOUNTOF_H@ : @HAVE_STDCOUNTOF_H@)
+# @INCLUDE_NEXT@ @NEXT_STDCOUNTOF_H@
+#else
+
+#ifndef _@GUARD_PREFIX@_STDCOUNTOF_H
+#define _@GUARD_PREFIX@_STDCOUNTOF_H
+
+/* This file uses _GL_GNUC_PREREQ.  */
+#if !_GL_CONFIG_H_INCLUDED
+ #error "Please include config.h first."
+#endif
+
+/* Get size_t.  */
+#include <stddef.h>
+
+/* Returns the number of elements of the array A, as a value of type size_t.
+
+   Example declarations of arrays:
+     extern int a[];
+     extern int a[10];
+     static int a[10][20];
+     void func () { int a[10]; ... }
+   It works for arrays that are declared outside functions and for local
+   variables of array type.  It does *not* work for function parameters
+   of array type, because they are actually parameters of pointer type.
+   In this case, i.e. if A is a pointer, e.g. in
+     void func (int a[10]) { ... }
+   this macro attempts to produce an error.
+ */
+#define countof(...) \
+  ((size_t) (sizeof (__VA_ARGS__) / sizeof (__VA_ARGS__)[0] \
+             + 0 * _gl_verify_is_array (__VA_ARGS__)))
+
+/* Attempts to verify that A is an array.  */
+#if defined __cplusplus
+/* Borrowed from verify.h.  */
+# if !GNULIB_defined_struct__gl_verify_type
+template <int w>
+  struct _gl_verify_type {
+    unsigned int _gl_verify_error_if_negative: w;
+  };
+#  define GNULIB_defined_struct__gl_verify_type 1
+# endif
+# if __cplusplus >= 201103L
+#  if 1
+  /* Use decltype.  */
+/* Default case.  */
+template <typename T>
+  struct _gl_array_type_test { static const int is_array = -1; };
+/* Unbounded arrays.  */
+template <typename T>
+  struct _gl_array_type_test<T[]> { static const int is_array = 1; };
+/* Bounded arrays.  */
+template <typename T, size_t N>
+  struct _gl_array_type_test<T[N]> { static const int is_array = 1; };
+/* String literals.  */
+template <typename T, size_t N>
+  struct _gl_array_type_test<T const (&)[N]> { static const int is_array = 1; };
+#   define _gl_verify_is_array(...) \
+     sizeof (_gl_verify_type<_gl_array_type_test<decltype(__VA_ARGS__)>::is_array>)
+#  else
+  /* Use template argument deduction.
+     Use sizeof to get a constant expression from an unknown type.
+     Note: This approach does not work for countof (((int[]) { a, b, c })).  */
+/* Default case.  */
+template <typename T>
+  struct _gl_array_type_test { double large; };
+/* Unbounded arrays.  */
+template <typename T>
+  struct _gl_array_type_test<T[]> { char small; };
+/* Bounded arrays.  */
+template <typename T, size_t N>
+  struct _gl_array_type_test<T[N]> { char small; };
+/* The T& parameter is essential here: it prevents decay (array-to-pointer
+   conversion).  */
+template <typename T> _gl_array_type_test<T> _gl_array_type_test_helper(T&);
+#   define _gl_verify_is_array(...) \
+     sizeof (_gl_verify_type<(sizeof (_gl_array_type_test_helper(__VA_ARGS__)) < sizeof (double) ? 1 : -1)>)
+#  endif
+# else
+/* The compiler does not have the necessary functionality.  */
+#  define _gl_verify_is_array(...) 0
+# endif
+#else
+/* In C, we can use typeof and __builtin_types_compatible_p.  */
+/* Work around clang bug <https://github.com/llvm/llvm-project/issues/143284>.  */
+# if (_GL_GNUC_PREREQ (3, 1) && ! defined __clang__ /* || defined __clang__ */) \
+     && !(defined __STRICT_ANSI__ && __STDC_VERSION__ < 202311L) /* but not with -std=c99 or -std=c11 */
+#  define _gl_verify_is_array(...) \
+    sizeof (struct { unsigned int _gl_verify_error_if_negative : __builtin_types_compatible_p (typeof (__VA_ARGS__), typeof (&*(__VA_ARGS__))) ? -1 : 1; })
+# else
+/* The compiler does not have the necessary built-ins.  */
+#  define _gl_verify_is_array(...) 0
+# endif
+#endif
+
+#endif /* _@GUARD_PREFIX@_STDCOUNTOF_H */
+#endif
+#endif /* _@GUARD_PREFIX@_STDCOUNTOF_H */
--- a/lib/stdio-consolesafe.c
+++ b/lib/stdio-consolesafe.c
@ -56,7 +56,7 @@ workaround_fwrite0 (char *s, size_t n, FILE *fp)
 }

 size_t
-gl_consolesafe_fwrite (const void *ptr, size_t size, size_t nmemb, FILE *fp)
+_gl_consolesafe_fwrite (const void *ptr, size_t size, size_t nmemb, FILE *fp)
 {
  size_t nbytes;
  if (ckd_mul (&nbytes, size, nmemb) || nbytes == 0)
@ -133,7 +133,7 @@ local_vasprintf (char **resultp, const char *format, va_list args)
   __mingw_*printf.  */

 int
-gl_consolesafe_fprintf (FILE *restrict fp, const char *restrict format, ...)
+_gl_consolesafe_fprintf (FILE *restrict fp, const char *restrict format, ...)
 {
  va_list args;
  va_start (args, format);
@ -151,7 +151,7 @@ gl_consolesafe_fprintf (FILE *restrict fp, const char *restrict format, ...)
 }

 int
-gl_consolesafe_printf (const char *restrict format, ...)
+_gl_consolesafe_printf (const char *restrict format, ...)
 {
  va_list args;
  va_start (args, format);
@ -169,8 +169,8 @@ gl_consolesafe_printf (const char *restrict format, ...)
 }

 int
-gl_consolesafe_vfprintf (FILE *restrict fp,
-                         const char *restrict format, va_list args)
+_gl_consolesafe_vfprintf (FILE *restrict fp,
+                          const char *restrict format, va_list args)
 {
  char *tmpstring;
  int result = vasprintf (&tmpstring, format, args);
@ -185,7 +185,7 @@ gl_consolesafe_vfprintf (FILE *restrict fp,
 }

 int
-gl_consolesafe_vprintf (const char *restrict format, va_list args)
+_gl_consolesafe_vprintf (const char *restrict format, va_list args)
 {
  char *tmpstring;
  int result = vasprintf (&tmpstring, format, args);
--- a/lib/stdio.in.h
+++ b/lib/stdio.in.h
@ -122,6 +122,20 @@
 # endif
 #endif

+/* _GL_ATTRIBUTE_DEALLOC_FREE declares that the function returns pointers that
+   can be freed via 'free'; it can be used only after declaring 'free'.  */
+/* Applies to: functions.  Cannot be used on inline functions.  */
+#ifndef _GL_ATTRIBUTE_DEALLOC_FREE
+# if defined __cplusplus && defined __GNUC__ && !defined __clang__
+/* Work around GCC bug <https://gcc.gnu.org/PR108231> */
+#  define _GL_ATTRIBUTE_DEALLOC_FREE \
+     _GL_ATTRIBUTE_DEALLOC ((void (*) (void *)) free, 1)
+# else
+#  define _GL_ATTRIBUTE_DEALLOC_FREE \
+     _GL_ATTRIBUTE_DEALLOC (free, 1)
+# endif
+#endif
+
 /* The __attribute__ feature is available in gcc versions 2.5 and later.
   The __-protected variants of the attributes 'format' and 'printf' are
   accepted by gcc versions 2.6.4 (effectively 2.7) and later.
@ -231,6 +245,50 @@

 /* The definition of _GL_WARN_ON_USE is copied here.  */

+/* Make _GL_ATTRIBUTE_DEALLOC_FREE work, even though <stdlib.h> may not have
+   been included yet.  */
+#if @GNULIB_FREE_POSIX@
+# if (@REPLACE_FREE@ && !defined free \
+      && !(defined __cplusplus && defined GNULIB_NAMESPACE))
+/* We can't do '#define free rpl_free' here.  */
+#  if defined __cplusplus && (__GLIBC__ + (__GLIBC_MINOR__ >= 14) > 2)
+_GL_EXTERN_C void rpl_free (void *) _GL_ATTRIBUTE_NOTHROW;
+#  else
+_GL_EXTERN_C void rpl_free (void *);
+#  endif
+#  undef _GL_ATTRIBUTE_DEALLOC_FREE
+#  define _GL_ATTRIBUTE_DEALLOC_FREE _GL_ATTRIBUTE_DEALLOC (rpl_free, 1)
+# else
+#  if defined _MSC_VER && !defined free
+_GL_EXTERN_C
+#   if defined _DLL
+     __declspec (dllimport)
+#   endif
+     void __cdecl free (void *);
+#  else
+#   if defined __cplusplus && (__GLIBC__ + (__GLIBC_MINOR__ >= 14) > 2)
+_GL_EXTERN_C void free (void *) _GL_ATTRIBUTE_NOTHROW;
+#   else
+_GL_EXTERN_C void free (void *);
+#   endif
+#  endif
+# endif
+#else
+# if defined _MSC_VER && !defined free
+_GL_EXTERN_C
+#   if defined _DLL
+     __declspec (dllimport)
+#   endif
+     void __cdecl free (void *);
+# else
+#  if defined __cplusplus && (__GLIBC__ + (__GLIBC_MINOR__ >= 14) > 2)
+_GL_EXTERN_C void free (void *) _GL_ATTRIBUTE_NOTHROW;
+#  else
+_GL_EXTERN_C void free (void *);
+#  endif
+# endif
+#endif
+
 /* Macros for stringification.  */
 #define _GL_STDIO_STRINGIZE(token) #token
 #define _GL_STDIO_MACROEXPAND_AND_STRINGIZE(token) _GL_STDIO_STRINGIZE(token)
@ -273,24 +331,24 @@

 #if (defined _WIN32 && !defined __CYGWIN__) && !defined _UCRT
 /* Workarounds against msvcrt bugs.  */
-_GL_FUNCDECL_SYS (gl_consolesafe_fwrite, size_t,
+_GL_FUNCDECL_SYS (_gl_consolesafe_fwrite, size_t,
                  (const void *ptr, size_t size, size_t nmemb, FILE *fp),
                  _GL_ARG_NONNULL ((1, 4)));
 # if defined __MINGW32__
-_GL_FUNCDECL_SYS (gl_consolesafe_fprintf, int,
+_GL_FUNCDECL_SYS (_gl_consolesafe_fprintf, int,
                  (FILE *restrict fp, const char *restrict format, ...),
                  _GL_ATTRIBUTE_FORMAT_PRINTF_STANDARD (2, 3)
                  _GL_ARG_NONNULL ((1, 2)));
-_GL_FUNCDECL_SYS (gl_consolesafe_printf, int,
+_GL_FUNCDECL_SYS (_gl_consolesafe_printf, int,
                  (const char *restrict format, ...),
                  _GL_ATTRIBUTE_FORMAT_PRINTF_STANDARD (1, 2)
                  _GL_ARG_NONNULL ((1)));
-_GL_FUNCDECL_SYS (gl_consolesafe_vfprintf, int,
+_GL_FUNCDECL_SYS (_gl_consolesafe_vfprintf, int,
                  (FILE *restrict fp,
                   const char *restrict format, va_list args),
                  _GL_ATTRIBUTE_FORMAT_PRINTF_STANDARD (2, 0)
                  _GL_ARG_NONNULL ((1, 2)));
-_GL_FUNCDECL_SYS (gl_consolesafe_vprintf, int,
+_GL_FUNCDECL_SYS (_gl_consolesafe_vprintf, int,
                  (const char *restrict format, va_list args),
                  _GL_ATTRIBUTE_FORMAT_PRINTF_STANDARD (1, 0)
                  _GL_ARG_NONNULL ((1)));
@ -633,7 +691,7 @@ _GL_CXXALIASWARN (fprintf);
 #elif defined __MINGW32__ && !defined _UCRT && __USE_MINGW_ANSI_STDIO
 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
 #  undef fprintf
-#  define fprintf gl_consolesafe_fprintf
+#  define fprintf _gl_consolesafe_fprintf
 # endif
 #endif
 #if !@GNULIB_FPRINTF_POSIX@ && defined GNULIB_POSIXCHECK
@ -985,7 +1043,7 @@ _GL_CXXALIASWARN (fwrite);
 #elif (defined _WIN32 && !defined __CYGWIN__) && !defined _UCRT
 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
 #  undef fwrite
-#  define fwrite gl_consolesafe_fwrite
+#  define fwrite _gl_consolesafe_fwrite
 # endif
 #endif

@ -1371,7 +1429,7 @@ _GL_CXXALIASWARN (printf);
 #elif defined __MINGW32__ && !defined _UCRT && __USE_MINGW_ANSI_STDIO
 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
 #  undef printf
-#  define printf gl_consolesafe_printf
+#  define printf _gl_consolesafe_printf
 # endif
 #endif
 #if !@GNULIB_PRINTF_POSIX@ && defined GNULIB_POSIXCHECK
@ -1808,6 +1866,26 @@ _GL_CXXALIAS_SYS (vasprintf, int,
 _GL_CXXALIASWARN (vasprintf);
 #endif

+#if @GNULIB_VAPRINTF@
+/* Write formatted output to a string dynamically allocated with malloc().
+   Return the resulting string.  Upon memory allocation error, or some
+   other error, return NULL, with errno set.  */
+_GL_FUNCDECL_SYS (aprintf, char *,
+                  (const char *format, ...),
+                  _GL_ATTRIBUTE_FORMAT_PRINTF_STANDARD (1, 2)
+                  _GL_ARG_NONNULL ((1))
+                  _GL_ATTRIBUTE_MALLOC _GL_ATTRIBUTE_DEALLOC_FREE);
+_GL_CXXALIAS_SYS (aprintf, char *,
+                  (const char *format, ...));
+_GL_FUNCDECL_SYS (vaprintf, char *,
+                  (const char *format, va_list args),
+                  _GL_ATTRIBUTE_FORMAT_PRINTF_STANDARD (1, 0)
+                  _GL_ARG_NONNULL ((1))
+                  _GL_ATTRIBUTE_MALLOC _GL_ATTRIBUTE_DEALLOC_FREE);
+_GL_CXXALIAS_SYS (vaprintf, char *,
+                  (const char *format, va_list args));
+#endif
+
 #if @GNULIB_VDZPRINTF@
 /* Prints formatted output to file descriptor FD.
   Returns the number of bytes written to the file descriptor.  Upon
@ -1918,7 +1996,7 @@ _GL_CXXALIASWARN (vfprintf);
 #elif defined __MINGW32__ && !defined _UCRT && __USE_MINGW_ANSI_STDIO
 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
 #  undef vfprintf
-#  define vfprintf gl_consolesafe_vfprintf
+#  define vfprintf _gl_consolesafe_vfprintf
 # endif
 #endif
 #if !@GNULIB_VFPRINTF_POSIX@ && defined GNULIB_POSIXCHECK
@ -2001,7 +2079,7 @@ _GL_CXXALIASWARN (vprintf);
 #elif defined __MINGW32__ && !defined _UCRT && __USE_MINGW_ANSI_STDIO
 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
 #  undef vprintf
-#  define vprintf gl_consolesafe_vprintf
+#  define vprintf _gl_consolesafe_vprintf
 # endif
 #endif
 #if !@GNULIB_VPRINTF_POSIX@ && defined GNULIB_POSIXCHECK
--- a/lib/stdlib.in.h
+++ b/lib/stdlib.in.h
@ -757,7 +757,7 @@ _GL_WARN_ON_USE (malloc, "malloc is not POSIX compliant everywhere - "
 #if @REPLACE_MB_CUR_MAX@
 # if !GNULIB_defined_MB_CUR_MAX
 _GL_STDLIB_INLINE size_t
-gl_MB_CUR_MAX (void)
+_gl_MB_CUR_MAX (void)
 {
 #  if 0 < @REPLACE_MB_CUR_MAX@
  return @REPLACE_MB_CUR_MAX@;
@ -768,7 +768,7 @@ gl_MB_CUR_MAX (void)
 #  endif
 }
 #  undef MB_CUR_MAX
-#  define MB_CUR_MAX gl_MB_CUR_MAX ()
+#  define MB_CUR_MAX _gl_MB_CUR_MAX ()
 #  define GNULIB_defined_MB_CUR_MAX 1
 # endif
 #endif
@ -1458,7 +1458,7 @@ _GL_WARN_ON_USE (setstate_r, "setstate_r is unportable - "

 #if @GNULIB_REALLOC_POSIX@
 # if @REPLACE_REALLOC_FOR_REALLOC_POSIX@
-#  if @REPLACE_REALLOC_FOR_REALLOC_POSIX@ == 2
+#  if @REPLACE_REALLOC_FOR_REALLOC_POSIX@ == 2 && !_GL_INLINE_RPL_REALLOC
 #   define _GL_INLINE_RPL_REALLOC 1
 #   ifdef __cplusplus
 extern "C" {
--- a/lib/strftime.c
+++ b/lib/strftime.c
@ -109,6 +109,7 @@
 #include <limits.h>
 #include <locale.h>
 #include <stdckdint.h>
+#include <stdcountof.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <stdlib.h>
@ -1882,7 +1883,7 @@ __strftime_internal (STREAM_OR_CHAR_T *s, STRFTIME_ARG (size_t maxsize)
 #endif
            }

-          bufp = buf + sizeof (buf) / sizeof (buf[0]);
+          bufp = buf + countof (buf);

          if (negative_number)
            u_number_value = - u_number_value;
@ -1913,7 +1914,7 @@ __strftime_internal (STREAM_OR_CHAR_T *s, STRFTIME_ARG (size_t maxsize)
            CHAR_T sign_char = (negative_number ? L_('-')
                                : always_output_a_sign ? L_('+')
                                : 0);
-            int number_bytes = buf + sizeof buf / sizeof buf[0] - bufp;
+            int number_bytes = buf + countof (buf) - bufp;
            int number_digits = number_bytes;
 #if SUPPORT_NON_GREG_CALENDARS_IN_STRFTIME
            if (digits_base >= 0x100)
@ -2098,7 +2099,7 @@ __strftime_internal (STREAM_OR_CHAR_T *s, STRFTIME_ARG (size_t maxsize)
            /* Generate string value for T using time_t arithmetic;
               this works even if sizeof (long) < sizeof (time_t).  */

-            bufp = buf + sizeof (buf) / sizeof (buf[0]);
+            bufp = buf + countof (buf);
            negative_number = t < 0;

            do
--- a/lib/string.in.h
+++ b/lib/string.in.h
@ -420,16 +420,19 @@ _GL_WARN_ON_USE_CXX (memchr,

 /* Are S1 and S2, of size N, bytewise equal?  */
 #if @GNULIB_MEMEQ@ && !@HAVE_DECL_MEMEQ@
-# ifdef __cplusplus
+# if !GNULIB_defined_memeq
+#  ifdef __cplusplus
 extern "C" {
-# endif
+#  endif
 _GL_MEMEQ_INLINE bool
 memeq (void const *__s1, void const *__s2, size_t __n)
 {
  return !memcmp (__s1, __s2, __n);
 }
-# ifdef __cplusplus
+#  ifdef __cplusplus
 }
+#  endif
+#  define GNULIB_defined_memeq 1
 # endif
 #endif

@ -805,16 +808,19 @@ _GL_CXXALIASWARN (strdup);

 /* Are strings S1 and S2 equal?  */
 #if @GNULIB_STREQ@ && !@HAVE_DECL_STREQ@
-# ifdef __cplusplus
+# if !GNULIB_defined_streq
+#  ifdef __cplusplus
 extern "C" {
-# endif
+#  endif
 _GL_STREQ_INLINE bool
 streq (char const *__s1, char const *__s2)
 {
  return !strcmp (__s1, __s2);
 }
-# ifdef __cplusplus
+#  ifdef __cplusplus
 }
+#  endif
+#  define GNULIB_defined_streq 1
 # endif
 #endif

@ -1041,7 +1047,7 @@ _GL_WARN_ON_USE_CXX (strrchr,
   If *STRINGP was already NULL, nothing happens.
   Return the old value of *STRINGP.

-   This is a variant of strtok() that is multithread-safe and supports
+   This is a variant of strtok() that is thread-safe and supports
   empty fields.

   Caveat: It modifies the original string.
@ -1179,7 +1185,7 @@ _GL_WARN_ON_USE (strcasestr, "strcasestr does work correctly on character "
        x = strtok_r(NULL, "=", &sp);   // x = NULL
                // s = "abc\0-def\0"

-   This is a variant of strtok() that is multithread-safe.
+   This is a variant of strtok() that is thread-safe.

   For the POSIX documentation for this function, see:
   https://pubs.opengroup.org/onlinepubs/9699919799/functions/strtok.html
@ -1245,13 +1251,14 @@ _GL_WARN_ON_USE (strtok_r, "strtok_r is unportable - "
     string + strlen (string)
   or to
     strchr (string, '\0').  */
-# ifdef __cplusplus
+# if !GNULIB_defined_strnul
+#  ifdef __cplusplus
 extern "C" {
-# endif
-_GL_STRNUL_INLINE const char *gl_strnul (const char *string)
+#  endif
+_GL_STRNUL_INLINE const char *_gl_strnul (const char *string)
     _GL_ATTRIBUTE_PURE
     _GL_ARG_NONNULL ((1));
-_GL_STRNUL_INLINE const char *gl_strnul (const char *string)
+_GL_STRNUL_INLINE const char *_gl_strnul (const char *string)
 {
  /* In gcc >= 7 or clang >= 4, we could use the expression
       strchr (string, '\0')
@ -1261,22 +1268,24 @@ _GL_STRNUL_INLINE const char *gl_strnul (const char *string)
     option '-fno-builtin' is in use.  */
  return string + strlen (string);
 }
-# ifdef __cplusplus
+#  ifdef __cplusplus
 }
-# endif
-# ifdef __cplusplus
+#  endif
+#  ifdef __cplusplus
+extern "C++" { /* needed for AIX and Solaris 10 */
 _GL_BEGIN_NAMESPACE
 template <typename T> T strnul (T);
 template <> inline const char *strnul<const char *> (const char *s)
-{ return gl_strnul (s); }
+{ return _gl_strnul (s); }
 template <> inline       char *strnul<      char *> (      char *s)
-{ return const_cast<char *>(gl_strnul (s)); }
+{ return const_cast<char *>(_gl_strnul (s)); }
 _GL_END_NAMESPACE
-# else
-#  if (defined __GNUC__ && __GNUC__ + (__GNUC_MINOR__ >= 9) > 4 && !defined __cplusplus) \
-      || (defined __clang__ && __clang_major__ >= 3) \
-      || (defined __SUNPRO_C && __SUNPRO_C >= 0x5150) \
-      || (__STDC_VERSION__ >= 201112L && !defined __GNUC__)
+}
+#  else
+#   if (defined __GNUC__ && __GNUC__ + (__GNUC_MINOR__ >= 9) > 4 && !defined __cplusplus) \
+       || (defined __clang__ && __clang_major__ >= 3) \
+       || (defined __SUNPRO_C && __SUNPRO_C >= 0x5150) \
+       || (__STDC_VERSION__ >= 201112L && !defined __GNUC__)
 /* The compiler supports _Generic from ISO C11.  */
 /* Since in C (but not in C++!), any function that accepts a '[const] char *'
   also accepts a '[const] void *' as argument, we make sure that the function-
@ -1284,14 +1293,16 @@ _GL_END_NAMESPACE
     char *, void *             -> void *
     const char *, const void * -> const void *
   This mapping is done through the conditional expression.  */
-#   define strnul(s) \
-      _Generic (1 ? (s) : (void *) 99, \
-                void *       : (char *) gl_strnul (s), \
-                const void * : gl_strnul (s))
-#  else
-#   define strnul(s) \
-      ((char *) gl_strnul (s))
+#    define strnul(s) \
+       _Generic (1 ? (s) : (void *) 99, \
+                 void *       : (char *) _gl_strnul (s), \
+                 const void * : _gl_strnul (s))
+#   else
+#    define strnul(s) \
+       ((char *) _gl_strnul (s))
+#   endif
 #  endif
+#  define GNULIB_defined_strnul 1
 # endif
 #endif

@ -1400,7 +1411,7 @@ _GL_EXTERN_C char * mbsstr (const char *haystack, const char *needle)
 /* Don't silently convert a 'const char *' to a 'char *'.  Programmers want
   compiler warnings for 'const' related mistakes.  */
 #  ifdef __cplusplus
-extern "C++" { /* needed for AIX */
+extern "C++" { /* needed for AIX and Solaris 10 */
 template <typename T>
  T * mbsstr_template (T* haystack, const char *needle);
 template <>
@ -1468,7 +1479,7 @@ _GL_EXTERN_C char * mbspcasecmp (const char *string, const char *prefix)
 /* Don't silently convert a 'const char *' to a 'char *'.  Programmers want
   compiler warnings for 'const' related mistakes.  */
 #  ifdef __cplusplus
-extern "C++" { /* needed for AIX */
+extern "C++" { /* needed for AIX and Solaris 10 */
 template <typename T>
  T * mbspcasecmp_template (T* string, const char *prefix);
 template <>
@ -1506,7 +1517,7 @@ _GL_EXTERN_C char * mbscasestr (const char *haystack, const char *needle)
 /* Don't silently convert a 'const char *' to a 'char *'.  Programmers want
   compiler warnings for 'const' related mistakes.  */
 #  ifdef __cplusplus
-extern "C++" { /* needed for AIX */
+extern "C++" { /* needed for AIX and Solaris 10 */
 template <typename T>
  T * mbscasestr_template (T* haystack, const char *needle);
 template <>
@ -1655,7 +1666,7 @@ _GL_WARN_ON_USE (strerror, "strerror is unportable - "
                 "use gnulib module strerror to guarantee non-NULL result");
 #endif

-/* Map any int, typically from errno, into an error message.  Multithread-safe.
+/* Map any int, typically from errno, into an error message.  Thread-safe.
   Uses the POSIX declaration, not the glibc declaration.  */
 #if @GNULIB_STRERROR_R@
 # if @REPLACE_STRERROR_R@
@ -1711,7 +1722,7 @@ _GL_WARN_ON_USE (strerror_l, "strerror_l is unportable - "
 # endif
 #endif

-/* Map any int, typically from errno, into an error message.  Multithread-safe,
+/* Map any int, typically from errno, into an error message.  Thread-safe,
   with locale_t argument.
   Not portable! Only provided by gnulib.  */
 #if @GNULIB_STRERROR_L@
--- a/lib/strnul.c
+++ b/lib/strnul.c
@ -1,4 +1,4 @@
-/* gl_strnul function.
+/* _gl_strnul function.
   Copyright (C) 2025-2026 Free Software Foundation, Inc.

   This file is free software: you can redistribute it and/or modify
--- a/lib/tempname.c
+++ b/lib/tempname.c
@ -111,9 +111,11 @@ random_bits (random_value *r, random_value s)
  __clock_gettime64 (CLOCK_REALTIME, &tv);
  v = mix_random_values (v, tv.tv_sec);
  v = mix_random_values (v, tv.tv_nsec);
+#else
+  v = mix_random_values (v, clock ());
 #endif

-  *r = mix_random_values (v, clock ());
+  *r = v;
  return false;
 }

--- a/lib/time_r.c
+++ b/lib/time_r.c
@ -22,7 +22,7 @@
 #include <time.h>

 /* The replacement functions in this file are only used on native Windows.
-   They are multithread-safe, because the gmtime() and localtime() functions
+   They are thread-safe, because the gmtime() and localtime() functions
   on native Windows — both in the ucrt and in the older MSVCRT — return a
   pointer to a 'struct tm' in thread-local memory.  */

--- a/lib/time_rz.c
+++ b/lib/time_rz.c
@ -18,7 +18,7 @@
 /* Written by Paul Eggert.  */

 /* Although this module is not thread-safe, any races should be fairly
-   rare and reasonably benign.  For complete thread-safety, use a C
+   rare and reasonably benign.  For complete thread safety, use a C
   library with a working timezone_t type, so that this module is not
   needed.  */

@ -118,7 +118,8 @@ save_abbr (timezone_t tz, struct tm *tm)
 {
 # if HAVE_STRUCT_TM_TM_ZONE
  char const *zone = tm->tm_zone;
-  char *zone_copy = (char *) "";
+  static char const mt[] = "";
+  char *zone_copy = (char *) mt;

  /* No need to replace null zones, or zones within the struct tm.  */
  if (!zone || ((char *) tm <= zone && zone < (char *) (tm + 1)))
--- a/lib/u64.h
+++ b/lib/u64.h
@ -46,10 +46,10 @@ extern "C" {
 /* Native implementations are trivial.  See below for comments on what
   these operations do.  */
 typedef uint64_t u64;
-# define u64hilo(hi, lo) ((u64) (((u64) (hi) << 32) + (lo)))
-# define u64init(hi, lo) u64hilo (hi, lo)
-# define u64lo(x) ((u64) (x))
-# define u64getlo(x) ((uint32_t) ((x) & UINT32_MAX))
+# define u64hilo(hi, lo) ((u64) {((u64) {(hi)} << 32) + (lo)})
+# define u64init(hi, lo) (((u64) (hi) << 32) + (lo))
+# define u64lo(x) ((u64) {(x)})
+# define u64getlo(x) ((uint32_t) {(x) & UINT32_MAX})
 # define u64size(x) u64lo (x)
 # define u64not(x) (~(x))
 # define u64lt(x, y) ((x) < (y))
--- a/m4/free.m4
+++ b/m4/free.m4
@ -1,5 +1,5 @@
 # free.m4
-# serial 6
+# serial 7
 dnl Copyright (C) 2003-2005, 2009-2026 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@ -18,6 +18,9 @@ AC_DEFUN([gl_FUNC_FREE],
  dnl So far, we know of three platforms that do this:
  dnl * glibc >= 2.33, thanks to the fix for this bug:
  dnl   <https://sourceware.org/PR17924>
+  dnl * musl >= 1.2.3, thanks to these commits:
+  dnl   <https://git.musl-libc.org/cgit/musl/commit/?id=9b77aaca86b53c367f23505c24dd3c02e240efad>
+  dnl   <https://git.musl-libc.org/cgit/musl/commit/?id=2010df0d64570db4ce29cc7df0e31f81aa26ae4a>
  dnl * OpenBSD >= 4.5, thanks to this commit:
  dnl   <https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/lib/libc/stdlib/malloc.c.diff?r1=1.100&r2=1.101&f=h>
  dnl * Solaris, because its malloc() implementation is based on brk(),
@ -26,11 +29,14 @@ AC_DEFUN([gl_FUNC_FREE],
  dnl documentation, or by code inspection of the free() implementation in libc.
  AC_CACHE_CHECK([whether free is known to preserve errno],
    [gl_cv_func_free_preserves_errno],
-    [AC_COMPILE_IFELSE(
+    [AC_REQUIRE([gl_MUSL_LIBC])
+     AC_COMPILE_IFELSE(
       [AC_LANG_PROGRAM(
          [[#include <stdlib.h>
+            #include <unistd.h>
          ]],
          [[#if 2 < __GLIBC__ + (33 <= __GLIBC_MINOR__)
+            #elif defined MUSL_LIBC && defined SEEK_DATA /* musl >= 1.2.3 */
            #elif defined __OpenBSD__
            #elif defined __sun
            #else
--- a/m4/gettext_h.m4
+++ b/m4/gettext_h.m4
@ -1,5 +1,5 @@
 # gettext_h.m4
-# serial 1
+# serial 3
 dnl Copyright (C) 2025-2026 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
--- a/m4/gnulib-common.m4
+++ b/m4/gnulib-common.m4
@ -1,5 +1,5 @@
 # gnulib-common.m4
-# serial 115
+# serial 122
 dnl Copyright (C) 2007-2026 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@ -436,6 +436,23 @@ AC_DEFUN([gl_COMMON_BODY], [
 # endif
 #endif

+/* _GL_ATTRIBUTE_COUNTED_BY (C) declares that the number of elements of
+   the field is given by C, which must be another field in the same struct.
+   The programmer is responsible for guaranteeing some invariants; see
+   <https://gcc.gnu.org/onlinedocs/gcc/Common-Attributes.html> for details.  */
+/* Applies to struct fields of type array or pointer (to data).  */
+#ifndef _GL_ATTRIBUTE_COUNTED_BY
+/* This attributes is supported
+     - for fields of array type: by gcc >= 16, clang >= 18,
+     - for fields of pointer type: by gcc when <https://gcc.gnu.org/PR125072>
+       will be fixed, clang >= 19.  */
+# if defined __clang__ && __clang_major__ >= 19
+#  define _GL_ATTRIBUTE_COUNTED_BY(c) __attribute__ ((__counted_by__ (c)))
+# else
+#  define _GL_ATTRIBUTE_COUNTED_BY(c)
+# endif
+#endif
+
 /* _GL_ATTRIBUTE_DEALLOC (F, I) declares that the function returns pointers
   that can be freed by passing them as the Ith argument to the
   function F.
@ -892,7 +909,7 @@ AC_DEFUN([gl_COMMON_BODY], [
 # endif
 #endif

-/* The following attributes enable detection of multithread-safety problems
+/* The following attributes enable detection of thread safety problems
   and resource leaks at compile-time, by clang ≥ 15, when the warning option
   -Wthread-safety is enabled.  For usage, see
   <https://clang.llvm.org/docs/ThreadSafetyAnalysis.html>.  */
@ -1234,9 +1251,9 @@ Amsterdam
 ])

 # AC_C_RESTRICT
-# This definition is copied from post-2.70 Autoconf and overrides the
-# AC_C_RESTRICT macro from autoconf 2.60..2.70.
-m4_version_prereq([2.70.1], [], [
+# This definition is copied from post-2.73 Autoconf and overrides the
+# AC_C_RESTRICT macro from autoconf 2.60..2.73.
+m4_version_prereq([2.73.1], [], [
 AC_DEFUN([AC_C_RESTRICT],
 [AC_CACHE_CHECK([for C/C++ restrict keyword], [ac_cv_c_restrict],
  [ac_cv_c_restrict=no
@ -1262,9 +1279,14 @@ AC_DEFUN([AC_C_RESTRICT],
  ])
 AH_VERBATIM([restrict],
 [/* Define to the equivalent of the C99 'restrict' keyword, or to
-   nothing if this is not supported.  Do not define if restrict is
-   supported only directly.  */
+   nothing if this is not supported.  In particular it is not supported
+   in MSVC 14.44 and in g++ 7 on Solaris 11, although these compilers
+   define __STDC_VERSION__ to 199901L.
+   Do not define if restrict is supported directly.  */
+#if ! (defined __STDC_VERSION__ && 199901L <= __STDC_VERSION__ \
+       && !defined _MSC_VER && !defined __cplusplus)
 #undef restrict
+#endif
 /* Work around a bug in older versions of Sun C++, which did not
   #define __restrict__ or support _Restrict or __restrict__
   even though the corresponding Sun C compiler ended up with
@ -1425,6 +1447,7 @@ AC_DEFUN([gl_CC_GNULIB_WARNINGS],
    dnl -Wno-pedantic                         >= 4.8          >= 3.9
    dnl -Wno-sign-compare                     >= 3            >= 3.9
    dnl -Wno-sign-conversion                  >= 4.3          >= 3.9
+    dnl -Wno-string-plus-int                  -               >= 3.9
    dnl -Wno-tautological-out-of-range-compare  -             >= 3.9
    dnl -Wno-type-limits                      >= 4.3          >= 3.9
    dnl -Wno-undef                            >= 3            >= 3.9
@ -1453,6 +1476,7 @@ AC_DEFUN([gl_CC_GNULIB_WARNINGS],
      -Wno-pedantic
      #endif
      #if 3 < __clang_major__ + (9 <= __clang_minor__)
+      -Wno-string-plus-int
      -Wno-tautological-constant-out-of-range-compare
      #endif
      #if (__GNUC__ + (__GNUC_MINOR__ >= 3) > 4 && !defined __clang__) || (__clang_major__ + (__clang_minor__ >= 9) > 3)
--- a/m4/gnulib-comp.m4
+++ b/m4/gnulib-comp.m4
@ -188,8 +188,10 @@ AC_DEFUN([gl_EARLY],
  # Code from module stdc_bit_width:
  # Code from module stdc_count_ones:
  # Code from module stdc_leading_zeros:
+  # Code from module stdc_memreverse8u:
  # Code from module stdc_trailing_zeros:
  # Code from module stdckdint-h:
+  # Code from module stdcountof-h:
  # Code from module stddef-h:
  # Code from module stdint-h:
  # Code from module stdio-h:
@ -554,16 +556,19 @@ AC_DEFUN([gl_INIT],
  gl_CONDITIONAL_HEADER([stdbit.h])
  AC_PROG_MKDIR_P
  AC_REQUIRE([gl_STDBIT_H])
-  GL_STDC_BIT_WIDTH=1
+  gl_STDBIT_MODULE_INDICATOR([stdc_bit_width])
  AC_REQUIRE([gl_STDBIT_H])
-  GL_STDC_COUNT_ONES=1
+  gl_STDBIT_MODULE_INDICATOR([stdc_count_ones])
  AC_REQUIRE([gl_STDBIT_H])
-  GL_STDC_LEADING_ZEROS=1
+  gl_STDBIT_MODULE_INDICATOR([stdc_leading_zeros])
  AC_REQUIRE([gl_STDBIT_H])
-  GL_STDC_TRAILING_ZEROS=1
+  gl_STDBIT_MODULE_INDICATOR([stdc_trailing_zeros])
  gl_STDCKDINT_H
  gl_CONDITIONAL_HEADER([stdckdint.h])
  AC_PROG_MKDIR_P
+  gl_STDCOUNTOF_H
+  gl_CONDITIONAL_HEADER([stdcountof.h])
+  AC_PROG_MKDIR_P
  gl_STDDEF_H
  gl_STDDEF_H_REQUIRE_DEFAULTS
  gl_CONDITIONAL_HEADER([stddef.h])
@ -614,7 +619,7 @@ AC_DEFUN([gl_INIT],
      ;;
  esac
  gl_CONDITIONAL([GL_COND_OBJ_STDIO_CONSOLESAFE], [test $USES_MSVCRT = 1])
-  AC_CHECK_FUNCS([vasprintf])
+  AC_CHECK_FUNCS_ONCE([vasprintf])
  gl_STDLIB_H
  gl_STDLIB_H_REQUIRE_DEFAULTS
  AC_PROG_MKDIR_P
@ -694,10 +699,8 @@ AC_DEFUN([gl_INIT],
    [Define to 1 if you want the FILE stream functions getc, putc, etc.
     to use unlocked I/O if available, throughout the package.
     Unlocked I/O can improve performance, sometimes dramatically.
-     But unlocked I/O is safe only in single-threaded programs,
-     as well as in multithreaded programs for which you can guarantee that
-     every FILE stream, including stdin, stdout, stderr, is used only
-     in a single thread.])
+     But unlocked I/O is safe only in processes in which two threads
+     never simultaneously access the same FILE stream.])
  AC_DEFINE([USE_UNLOCKED_IO], [GNULIB_STDIO_SINGLE_THREAD],
    [An alias of GNULIB_STDIO_SINGLE_THREAD.])
  gl_FUNC_GLIBC_UNLOCKED_IO
@ -727,6 +730,7 @@ AC_DEFUN([gl_INIT],
  gl_gnulib_enabled_03e0aaad4cb89ca757653bd367a6ccb7=false
  gl_gnulib_enabled_rawmemchr=false
  gl_gnulib_enabled_6099e9737f757db36c47fa9d9f02e88c=false
+  gl_gnulib_enabled_stdc_memreverse8u=false
  gl_gnulib_enabled_strtoll=false
  gl_gnulib_enabled_utimens=false
  gl_gnulib_enabled_verify=false
@ -945,6 +949,14 @@ AC_DEFUN([gl_INIT],
      gl_gnulib_enabled_6099e9737f757db36c47fa9d9f02e88c=true
    fi
  }
+  func_gl_gnulib_m4code_stdc_memreverse8u ()
+  {
+    if $gl_gnulib_enabled_stdc_memreverse8u; then :; else
+      AC_REQUIRE([gl_STDBIT_H])
+      gl_STDBIT_MODULE_INDICATOR([stdc_memreverse8u])
+      gl_gnulib_enabled_stdc_memreverse8u=true
+    fi
+  }
  func_gl_gnulib_m4code_strtoll ()
  {
    if $gl_gnulib_enabled_strtoll; then :; else
@ -972,6 +984,9 @@ AC_DEFUN([gl_INIT],
      gl_gnulib_enabled_verify=true
    fi
  }
+  if $GL_GENERATE_BYTESWAP_H; then
+    func_gl_gnulib_m4code_stdc_memreverse8u
+  fi
  if test $HAVE_CANONICALIZE_FILE_NAME = 0 || test $REPLACE_CANONICALIZE_FILE_NAME = 1; then
    func_gl_gnulib_m4code_925677f0343de64b89a9f0c790b4104c
  fi
@ -1087,6 +1102,7 @@ AC_DEFUN([gl_INIT],
  AM_CONDITIONAL([gl_GNULIB_ENABLED_03e0aaad4cb89ca757653bd367a6ccb7], [$gl_gnulib_enabled_03e0aaad4cb89ca757653bd367a6ccb7])
  AM_CONDITIONAL([gl_GNULIB_ENABLED_rawmemchr], [$gl_gnulib_enabled_rawmemchr])
  AM_CONDITIONAL([gl_GNULIB_ENABLED_6099e9737f757db36c47fa9d9f02e88c], [$gl_gnulib_enabled_6099e9737f757db36c47fa9d9f02e88c])
+  AM_CONDITIONAL([gl_GNULIB_ENABLED_stdc_memreverse8u], [$gl_gnulib_enabled_stdc_memreverse8u])
  AM_CONDITIONAL([gl_GNULIB_ENABLED_strtoll], [$gl_gnulib_enabled_strtoll])
  AM_CONDITIONAL([gl_GNULIB_ENABLED_utimens], [$gl_gnulib_enabled_utimens])
  AM_CONDITIONAL([gl_GNULIB_ENABLED_verify], [$gl_gnulib_enabled_verify])
@ -1463,13 +1479,14 @@ AC_DEFUN([gl_FILE_LIST], [
  lib/signal.in.h
  lib/stat-time.c
  lib/stat-time.h
-  lib/stdbit.c
  lib/stdbit.in.h
  lib/stdc_bit_width.c
  lib/stdc_count_ones.c
  lib/stdc_leading_zeros.c
+  lib/stdc_memreverse8u.c
  lib/stdc_trailing_zeros.c
  lib/stdckdint.in.h
+  lib/stdcountof.in.h
  lib/stddef.in.h
  lib/stdint.in.h
  lib/stdio-consolesafe.c
@ -1633,6 +1650,7 @@ AC_DEFUN([gl_FILE_LIST], [
  m4/stdalign.m4
  m4/stdbit_h.m4
  m4/stdckdint_h.m4
+  m4/stdcountof_h.m4
  m4/stddef_h.m4
  m4/stdint.m4
  m4/stdio_h.m4
--- a/m4/manywarnings.m4
+++ b/m4/manywarnings.m4
@ -1,5 +1,5 @@
 # manywarnings.m4
-# serial 32
+# serial 35
 dnl Copyright (C) 2008-2026 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@ -97,7 +97,8 @@ AC_DEFUN([gl_MANYWARN_ALL_GCC(C)],
  # export LC_ALL=C && comm -3 \
  #  <((sed -n 's/^  *\(-[^ 0-9][^ ]*\).*/\1/p' manywarnings.m4; \
  #     awk '/^[^#]/ {print $1}' ../build-aux/gcc-warning.spec) | sort) \
-  #  <(gcc --help=warnings | sed -n 's/^  \(-[^ ]*\) .*/\1/p' | sort)
+  #  <((gcc --help=c,warnings && gcc --help=common,warnings) \
+  #    | sed -n 's/^  \(-[^ ]*\) .*/\1/p' | sort)

  $1=
  for gl_manywarn_item in -fanalyzer -fstrict-flex-arrays \
@ -112,9 +113,11 @@ AC_DEFUN([gl_MANYWARN_ALL_GCC(C)],
    -Wextra \
    -Wflex-array-member-not-at-end \
    -Wformat-signedness \
+    -Wfree-labels \
    -Winit-self \
    -Winline \
    -Winvalid-pch \
+    -Wkeyword-macro \
    -Wlogical-op \
    -Wmissing-declarations \
    -Wmissing-include-dirs \
@ -162,6 +165,7 @@ AC_DEFUN([gl_MANYWARN_ALL_GCC(C)],
  AS_VAR_APPEND([$1], [' -Wformat-truncation=2'])
  AS_VAR_APPEND([$1], [' -Wimplicit-fallthrough=5'])
  AS_VAR_APPEND([$1], [' -Wshift-overflow=2'])
+  AS_VAR_APPEND([$1], [' -Wstringop-overflow=4'])
  AS_VAR_APPEND([$1], [' -Wuse-after-free=3'])
  AS_VAR_APPEND([$1], [' -Wunused-const-variable=2'])
  AS_VAR_APPEND([$1], [' -Wvla-larger-than=4031'])
@ -180,6 +184,15 @@ AC_DEFUN([gl_MANYWARN_ALL_GCC(C)],
        AS_VAR_APPEND([$1], [' -fno-common'])
          ;;
    esac
+    case $gl_gcc_version in
+      gcc*' ('*') '?.* | gcc*' ('*') '1[[0-3]].*)
+          # In GCC < 14 the option either does not exist,
+          # or is accepted but always warns.
+          ;;
+      *)
+          AS_VAR_APPEND([$1], [' -Wuseless-cast'])
+          ;;
+    esac
    case $gl_gcc_version in
      gcc*' ('*') '?.* | gcc*' ('*') '1[[0-4]].*)
          # In GCC < 15 the option either does not exist,
@ -194,6 +207,20 @@ AC_DEFUN([gl_MANYWARN_ALL_GCC(C)],
  # These options are not supported by gcc, but are useful with clang.
  AS_VAR_APPEND([$1], [' -Wthread-safety'])

+  # These options are not supported by gcc, only by clang.  clang enables
+  # them by default, but they are never useful.  So, disable them.
+  # Note! This applies *only* to options that are really never useful.
+  #       When in doubt, let the package maintainer decide.  The principle
+  #       of this module is to enable *all* possible warnings and then allow
+  #       the package maintainer to disable warnings they find not useful
+  #       in the context of their package.
+  # Gnulib uses #include_next in many .h files.
+  AS_VAR_APPEND([$1], [' -Wno-gnu-include-next'])
+  # C programmers know what '+' does. These warning options are targeted
+  # at fresh C programmers that are used to JavaScript, Java, or C#.
+  AS_VAR_APPEND([$1], [' -Wno-string-plus-int'])
+  AS_VAR_APPEND([$1], [' -Wno-string-plus-char'])
+
  # Disable specific options as needed.
  if test "$gl_cv_cc_nomfi_needed" = yes; then
    AS_VAR_APPEND([$1], [' -Wno-missing-field-initializers'])
--- a/m4/pthread_sigmask.m4
+++ b/m4/pthread_sigmask.m4
@ -1,5 +1,5 @@
 # pthread_sigmask.m4
-# serial 24
+# serial 26
 dnl Copyright (C) 2011-2026 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@ -19,7 +19,7 @@ AC_DEFUN([gl_FUNC_PTHREAD_SIGMASK],
    [AC_EGREP_CPP([headers_define_pthread_sigmask], [
 #include <pthread.h>
 #include <signal.h>
-#ifdef pthread_sigmask
+#if defined _WIN32 && defined pthread_sigmask
 headers_define_pthread_sigmask
 #endif],
       [gl_cv_func_pthread_sigmask_macro=yes],
@ -103,6 +103,27 @@ AC_DEFUN([gl_FUNC_PTHREAD_SIGMASK],
    ])
  fi

+  dnl We want to be able to use pthread_sigmask as a thread-safe
+  dnl replacement of sigprocmask, in both single-threaded and multithreaded
+  dnl processes. Therefore enforce PTHREAD_SIGMASK_LIB to be empty, whenever
+  dnl possible.
+  if test -n "$PTHREAD_SIGMASK_LIB"; then
+    dnl We get here on glibc ≤ 2.31, NetBSD, OpenBSD ≤ 5.8, AIX.
+    dnl Except on AIX, pthread_sigmask and sigprocmask are equivalent.
+    dnl Whereas on AIX, sigprocmask is not allowed in multithreaded processes
+    dnl <https://www.ibm.com/docs/en/aix/7.2.0?topic=s-sigprocmask-sigsetmask-sigblock-subroutine>.
+    AC_REQUIRE([AC_CANONICAL_HOST])
+    case "$host_os" in
+      aix*) ;;
+      *)
+        REPLACE_PTHREAD_SIGMASK=1
+        AC_DEFINE([PTHREAD_SIGMASK_NOT_IN_LIBC], [1],
+          [Define to 1 if pthread_sigmask requires linking with some library.])
+        PTHREAD_SIGMASK_LIB=
+        ;;
+    esac
+  fi
+
  AC_SUBST([PTHREAD_SIGMASK_LIB])
  dnl For backward compatibility.
  LIB_PTHREAD_SIGMASK="$PTHREAD_SIGMASK_LIB"
@ -163,6 +184,8 @@ AC_DEFUN([gl_FUNC_PTHREAD_SIGMASK],

    dnl On Cygwin 1.7.5, the pthread_sigmask() has a wrong return value
    dnl convention: Upon failure, it returns -1 and sets errno.
+    dnl Likewise on NetBSD 9.3, when libpthread is not in use; see
+    dnl https://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=57214 .
    AC_CACHE_CHECK([whether pthread_sigmask returns error numbers],
      [gl_cv_func_pthread_sigmask_return_works],
      [
--- a/m4/regex.m4
+++ b/m4/regex.m4
@ -1,5 +1,5 @@
 # regex.m4
-# serial 81
+# serial 82
 dnl Copyright (C) 1996-2001, 2003-2026 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@ -318,6 +318,39 @@ AC_DEFUN([gl_REGEX],
                free (regs.end);
              }

+            /* These tests are derived from bug#68725, reported by
+               Ed Morton.  The regex uses backrefs with optional groups
+               to detect palindromes.  */
+            {
+              regex_t re68725;
+              i = regcomp (&re68725,
+                           "^(.?)(.?).?\\\\2\\\\1$",
+                           REG_EXTENDED);
+              if (i)
+                result |= 64;
+              else
+                {
+                  regmatch_t pm[3];
+                  /* "ab" is not a palindrome, so must not match
+                     with $.  */
+                  if (regexec (&re68725, "ab", 1, pm, 0) == 0)
+                    result |= 64;
+                  /* Without $, a shorter match (e.g., empty or "a")
+                     is valid at position 0.  Ensure set_regs retries
+                     with a shorter match_last when the longest
+                     structural match fails content validation.  */
+                  regfree (&re68725);
+                  i = regcomp (&re68725,
+                               "^(.?)(.?).?\\\\2\\\\1",
+                               REG_EXTENDED);
+                  if (i)
+                    result |= 64;
+                  else if (regexec (&re68725, "ab", 3, pm, 0) != 0)
+                    result |= 64;
+                  regfree (&re68725);
+                }
+            }
+
 #if 0
            /* It would be nice to reject hosts whose regoff_t values are too
               narrow (including glibc on hosts with 64-bit ptrdiff_t and
--- a/m4/stdbit_h.m4
+++ b/m4/stdbit_h.m4
@ -1,5 +1,5 @@
 # stdbit_h.m4
-# serial 2
+# serial 14
 dnl Copyright 2024-2026 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@ -12,27 +12,74 @@ AC_DEFUN_ONCE([gl_STDBIT_H],
 [
  AC_REQUIRE([gl_BIGENDIAN])

-  AC_CHECK_HEADERS_ONCE([stdbit.h])
-  if test $ac_cv_header_stdbit_h = yes; then
-    GL_GENERATE_STDBIT_H=false
+  gl_CHECK_NEXT_HEADERS([stdbit.h])
+  if test "$ac_cv_header_stdbit_h" = yes; then
+    HAVE_STDBIT_H=1
+  else
+    HAVE_STDBIT_H=0
+  fi
+  AC_SUBST([HAVE_STDBIT_H])
+  AM_CONDITIONAL([GL_HAVE_STDBIT_H], [test "$ac_cv_header_stdbit_h" = yes])
+
+  if test "$ac_cv_header_stdbit_h" = yes; then
+    dnl We may have a stdbit.h without C2y features.
+    AC_CHECK_DECLS([stdc_rotate_left_uc], , , [[#include <stdbit.h>]])
+    if test "$ac_cv_have_decl_stdc_rotate_left_uc" = no; then
+      GL_GENERATE_STDBIT_H=true
+    else
+      GL_GENERATE_STDBIT_H=false
+    fi
  else
    GL_GENERATE_STDBIT_H=true
  fi
-
-  dnl We don't use gl_MODULE_INDICATOR_INIT_VARIABLE here, because stdbit.in.h
-  dnl does not use #include_next.
-  GL_STDC_LEADING_ZEROS=0;       AC_SUBST([GL_STDC_LEADING_ZEROS])
-  GL_STDC_LEADING_ONES=0;        AC_SUBST([GL_STDC_LEADING_ONES])
-  GL_STDC_TRAILING_ZEROS=0;      AC_SUBST([GL_STDC_TRAILING_ZEROS])
-  GL_STDC_TRAILING_ONES=0;       AC_SUBST([GL_STDC_TRAILING_ONES])
-  GL_STDC_FIRST_LEADING_ZERO=0;  AC_SUBST([GL_STDC_FIRST_LEADING_ZERO])
-  GL_STDC_FIRST_LEADING_ONE=0;   AC_SUBST([GL_STDC_FIRST_LEADING_ONE])
-  GL_STDC_FIRST_TRAILING_ZERO=0; AC_SUBST([GL_STDC_FIRST_TRAILING_ZERO])
-  GL_STDC_FIRST_TRAILING_ONE=0;  AC_SUBST([GL_STDC_FIRST_TRAILING_ONE])
-  GL_STDC_COUNT_ZEROS=0;         AC_SUBST([GL_STDC_COUNT_ZEROS])
-  GL_STDC_COUNT_ONES=0;          AC_SUBST([GL_STDC_COUNT_ONES])
-  GL_STDC_HAS_SINGLE_BIT=0;      AC_SUBST([GL_STDC_HAS_SINGLE_BIT])
-  GL_STDC_BIT_WIDTH=0;           AC_SUBST([GL_STDC_BIT_WIDTH])
-  GL_STDC_BIT_FLOOR=0;           AC_SUBST([GL_STDC_BIT_FLOOR])
-  GL_STDC_BIT_CEIL=0;            AC_SUBST([GL_STDC_BIT_CEIL])
+])
+
+# gl_STDBIT_MODULE_INDICATOR([modulename])
+# sets the shell variable that indicates the presence of the given module
+# to a C preprocessor expression that will evaluate to 1.
+# This macro invocation must not occur in macros that are AC_REQUIREd.
+AC_DEFUN([gl_STDBIT_MODULE_INDICATOR],
+[
+  dnl Ensure to expand the default settings once only.
+  gl_STDBIT_H_REQUIRE_DEFAULTS
+  gl_MODULE_INDICATOR_SET_VARIABLE([$1])
+  dnl Define it also as a C macro, for the benefit of the unit tests.
+  gl_MODULE_INDICATOR_FOR_TESTS([$1])
+])
+
+# Initializes the default values for AC_SUBSTed shell variables.
+# This macro must not be AC_REQUIREd.  It must only be invoked, and only
+# outside of macros or in macros that are not AC_REQUIREd.
+AC_DEFUN([gl_STDBIT_H_REQUIRE_DEFAULTS],
+[
+  m4_defun(GL_MODULE_INDICATOR_PREFIX[_STDBIT_H_MODULE_INDICATOR_DEFAULTS], [
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_LEADING_ZEROS])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_LEADING_ONES])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_TRAILING_ZEROS])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_TRAILING_ONES])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_FIRST_LEADING_ZERO])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_FIRST_LEADING_ONE])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_FIRST_TRAILING_ZERO])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_FIRST_TRAILING_ONE])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_COUNT_ZEROS])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_COUNT_ONES])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_HAS_SINGLE_BIT])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_BIT_WIDTH])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_BIT_FLOOR])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_BIT_CEIL])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_ROTATE_LEFT])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_ROTATE_RIGHT])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_MEMREVERSE8])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_MEMREVERSE8U])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_LOAD8_ALIGNED])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_LOAD8])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_STORE8_ALIGNED])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDC_STORE8])
+  ])
+  m4_require(GL_MODULE_INDICATOR_PREFIX[_STDBIT_H_MODULE_INDICATOR_DEFAULTS])
+  AC_REQUIRE([gl_STDBIT_H_DEFAULTS])
+])
+
+AC_DEFUN([gl_STDBIT_H_DEFAULTS],
+[
 ])
--- a/m4/stdckdint_h.m4
+++ b/m4/stdckdint_h.m4
@ -1,5 +1,5 @@
 # stdckdint_h.m4
-# serial 1
+# serial 2
 dnl Copyright 2025-2026 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@ -52,7 +52,7 @@ AC_DEFUN_ONCE([gl_STDCKDINT_H],
      HAVE_C_STDCKDINT_H=0
      HAVE_WORKING_C_STDCKDINT_H=0
    fi
-    if test "$CXX" != no; then
+    if test -n "$CXX" && test "$CXX" != no; then
      AC_CACHE_CHECK([whether stdckdint.h can be included in C++],
        [gl_cv_header_cxx_stdckdint_h],
        [dnl We can't use AC_LANG_PUSH([C++]) and AC_LANG_POP([C++]) here, due to
@ -114,7 +114,7 @@ EOF
  AC_SUBST([HAVE_CXX_STDCKDINT_H])
  AC_SUBST([HAVE_WORKING_CXX_STDCKDINT_H])

-  if test "$CXX" != no; then
+  if test -n "$CXX" && test "$CXX" != no; then
    dnl We might need the header for C or C++.
    if test $HAVE_C_STDCKDINT_H = 1 \
       && test $HAVE_WORKING_C_STDCKDINT_H = 1 \
--- a/m4/stdcountof_h.m4
+++ b/m4/stdcountof_h.m4
@ -0,0 +1,53 @@
+# stdcountof_h.m4
+# serial 3
+dnl Copyright 2025-2026 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+dnl This file is offered as-is, without any warranty.
+
+AC_DEFUN_ONCE([gl_STDCOUNTOF_H],
+[
+  AC_CHECK_HEADERS_ONCE([stdcountof.h])
+  gl_CHECK_NEXT_HEADERS([stdcountof.h])
+  if test $ac_cv_header_stdcountof_h = yes; then
+    HAVE_STDCOUNTOF_H=1
+  else
+    HAVE_STDCOUNTOF_H=0
+  fi
+  AC_SUBST([HAVE_STDCOUNTOF_H])
+
+  dnl In clang 21, <stdcountof.h> exists but does not work in C++ mode, because
+  dnl it uses _Countof, which is not a compiler built-in in C++ mode.
+  m4_ifdef([gl_ANSI_CXX], [AC_REQUIRE([gl_ANSI_CXX])])
+  CXX_HAVE_STDCOUNTOF_H=1
+  if test -n "$CXX" && test "$CXX" != no; then
+    AC_CACHE_CHECK([whether the C++ compiler has <stdcountof.h>],
+      [gl_cv_cxx_have_stdcountof_h],
+      [dnl We can't use AC_LANG_PUSH([C++]) and AC_LANG_POP([C++]) here, due to
+       dnl an autoconf bug <https://savannah.gnu.org/support/?110294>.
+       cat > conftest.cpp <<\EOF
+#include <stdcountof.h>
+int a[] = { 86, 47 };
+unsigned int a_n = countof (a);
+EOF
+       gl_command="$CXX $CXXFLAGS $CPPFLAGS -c conftest.cpp"
+       if AC_TRY_EVAL([gl_command]); then
+         gl_cv_cxx_have_stdcountof_h=yes
+       else
+         gl_cv_cxx_have_stdcountof_h=no
+       fi
+       rm -fr conftest*
+      ])
+    if test $gl_cv_cxx_have_stdcountof_h != yes; then
+      CXX_HAVE_STDCOUNTOF_H=0
+    fi
+  fi
+  AC_SUBST([CXX_HAVE_STDCOUNTOF_H])
+
+  if test $HAVE_STDCOUNTOF_H = 1 && test $CXX_HAVE_STDCOUNTOF_H = 1; then
+    GL_GENERATE_STDCOUNTOF_H=false
+  else
+    GL_GENERATE_STDCOUNTOF_H=true
+  fi
+])
--- a/m4/stdio_h.m4
+++ b/m4/stdio_h.m4
@ -1,5 +1,5 @@
 # stdio_h.m4
-# serial 75
+# serial 76
 dnl Copyright (C) 2007-2026 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@ -182,6 +182,7 @@ AC_DEFUN([gl_STDIO_H_REQUIRE_DEFAULTS],
    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_STDIO_H_SIGPIPE])
    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_SZPRINTF])
    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_TMPFILE])
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_VAPRINTF])
    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_VASPRINTF])
    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_VASZPRINTF])
    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_VFSCANF])
@ -208,6 +209,8 @@ AC_DEFUN([gl_STDIO_H_REQUIRE_DEFAULTS],
    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_MDA_TEMPNAM], [1])
  ])
  m4_require(GL_MODULE_INDICATOR_PREFIX[_STDIO_H_MODULE_INDICATOR_DEFAULTS])
+  dnl Make sure the shell variable for GNULIB_FREE_POSIX is initialized.
+  gl_STDLIB_H_REQUIRE_DEFAULTS
  AC_REQUIRE([gl_STDIO_H_DEFAULTS])
 ])