Update from Gnulib by running admin/merge-gnulib

7 files changed, 196 insertions, 52 deletions

diff --git a/m4/acl.m4 b/m4/acl.m4
index 7e4b0e354d9..2dd33497efd 100644
--- a/m4/acl.m4
+++ b/m4/acl.m4
@@ -1,5 +1,5 @@
 # acl.m4
-# serial 35
+# serial 37
 dnl Copyright (C) 2002, 2004-2025 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -12,7 +12,6 @@ dnl This file is offered as-is, without any warranty.
 
 AC_DEFUN([gl_FUNC_ACL_ARG],
 [
-  gl_need_lib_has_acl=
   AC_ARG_ENABLE([acl],
     AS_HELP_STRING([[--disable-acl]], [do not support ACLs]),
     , [enable_acl=auto])
@@ -22,6 +21,7 @@ AC_DEFUN([gl_FUNC_ACL_ARG],
     [], [with_libsmack=maybe])
 ])
 
+# Prerequisites of module acl-permissions.
 AC_DEFUN_ONCE([gl_FUNC_ACL],
 [
   AC_REQUIRE([gl_FUNC_ACL_ARG])
@@ -145,9 +145,6 @@ int type = ACL_TYPE_EXTENDED;]])],
       AC_MSG_WARN([AC_PACKAGE_NAME will be built without ACL support.])
     fi
   fi
-  if test -n "$gl_need_lib_has_acl"; then
-    FILE_HAS_ACL_LIB=$LIB_ACL
-  fi
   AC_SUBST([LIB_ACL])
   AC_DEFINE_UNQUOTED([USE_ACL], [$use_acl],
     [Define to nonzero if you want access control list support.])
@@ -187,6 +184,7 @@ AC_DEFUN([gl_ACL_GET_FILE],
 AC_DEFUN([gl_FILE_HAS_ACL],
 [
   AC_REQUIRE([gl_FUNC_ACL_ARG])
+  AC_REQUIRE([gl_FUNC_ACL])
   # On GNU/Linux, testing if a file has an acl can be done with the
   # listxattr and getxattr syscalls, which don't require linking
   # against additional libraries.  Assume this works if linux/attr.h
@@ -224,10 +222,7 @@ AC_DEFUN([gl_FILE_HAS_ACL],
   AS_CASE([$enable_acl,$gl_file_has_acl_uses_selinux,$gl_file_has_acl_uses_smack],
     [no,* | *,yes,* | *,yes], [],
     [*],
-      [dnl Set gl_need_lib_has_acl to a nonempty value, so that any
-       dnl later gl_FUNC_ACL call will set FILE_HAS_ACL_LIB=$LIB_ACL.
-       gl_need_lib_has_acl=1
-       FILE_HAS_ACL_LIB=$LIB_ACL])
+      [FILE_HAS_ACL_LIB=$LIB_ACL])
   AC_SUBST([FILE_HAS_ACL_LIB])
 ])
 
@@ -235,10 +230,11 @@ AC_DEFUN([gl_FILE_HAS_ACL],
 AC_DEFUN([gl_QCOPY_ACL],
 [
   AC_REQUIRE([gl_FUNC_ACL])
+  AC_REQUIRE([gl_FILE_HAS_ACL])
   AC_CHECK_HEADERS_ONCE([linux/xattr.h])
   gl_FUNC_XATTR
   if test "$use_xattr" = yes; then
-    QCOPY_ACL_LIB="$LIB_XATTR"
+    QCOPY_ACL_LIB="$LIB_XATTR $FILE_HAS_ACL_LIB"
   else
     QCOPY_ACL_LIB="$LIB_ACL"
   fi
diff --git a/m4/gnulib-common.m4 b/m4/gnulib-common.m4
index a07c7dd5a89..d525d8b1faa 100644
--- a/m4/gnulib-common.m4
+++ b/m4/gnulib-common.m4
@@ -1,5 +1,5 @@
 # gnulib-common.m4
-# serial 110
+# serial 112
 dnl Copyright (C) 2007-2025 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -57,33 +57,24 @@ AC_DEFUN([gl_COMMON_BODY], [
 #endif
 ])
   AH_VERBATIM([_Noreturn],
-[/* The _Noreturn keyword of C11.  */
+[/* The _Noreturn keyword of C11.
+   Do not use [[noreturn]], because with it the syntax
+     extern _Noreturn void func (...);
+   would not be valid; such a declaration would be valid only with 'extern'
+   and '_Noreturn' swapped, or without the 'extern' keyword.  However, some
+   AIX system header files and several gnulib header files use precisely
+   this syntax with 'extern'.  So even though C23 deprecates _Noreturn,
+   it is currently more portable to prefer it to [[noreturn]].
+
+   Also, do not try to work around LLVM bug 59792 (clang 15 or earlier).
+   This rare bug can be worked around by compiling with 'clang -D_Noreturn=',
+   though the workaround may generate many false-alarm warnings.  */
 #ifndef _Noreturn
-# if (defined __cplusplus \
-      && ((201103 <= __cplusplus && !(__GNUC__ == 4 && __GNUC_MINOR__ == 7)) \
-          || (defined _MSC_VER && 1900 <= _MSC_VER)) \
-      && 0)
-    /* [[noreturn]] is not practically usable, because with it the syntax
-         extern _Noreturn void func (...);
-       would not be valid; such a declaration would only be valid with 'extern'
-       and '_Noreturn' swapped, or without the 'extern' keyword.  However, some
-       AIX system header files and several gnulib header files use precisely
-       this syntax with 'extern'.  */
-#  define _Noreturn [[noreturn]]
-# elif (defined __clang__ && __clang_major__ < 16 \
-        && defined _GL_WORK_AROUND_LLVM_BUG_59792)
-   /* Compile with -D_GL_WORK_AROUND_LLVM_BUG_59792 to work around
-      that rare LLVM bug, though you may get many false-alarm warnings.  */
-#  define _Noreturn
-# elif ((!defined __cplusplus || defined __clang__) \
-        && (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) \
-            || (!defined __STRICT_ANSI__ \
-                && (_GL_GNUC_PREREQ (4, 7) \
-                    || (defined __apple_build_version__ \
-                        ? 6000000 <= __apple_build_version__ \
-                        : 3 < __clang_major__ + (5 <= __clang_minor__))))))
+# if 201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0)
    /* _Noreturn works as-is.  */
 # elif _GL_GNUC_PREREQ (2, 8) || defined __clang__ || 0x5110 <= __SUNPRO_C
+   /* Prefer __attribute__ ((__noreturn__)) to plain _Noreturn even if the
+      latter works, as 'gcc -std=gnu99 -Wpedantic' warns about _Noreturn.  */
 #  define _Noreturn __attribute__ ((__noreturn__))
 # elif 1200 <= (defined _MSC_VER ? _MSC_VER : 0)
 #  define _Noreturn __declspec (noreturn)
@@ -955,8 +946,8 @@ AC_DEFUN([gl_COMMON_BODY], [
      -1 if n1 < n2
    The naïve code   (n1 > n2 ? 1 : n1 < n2 ? -1 : 0)  produces a conditional
    jump with nearly all GCC versions up to GCC 10.
-   This variant     (n1 < n2 ? -1 : n1 > n2)  produces a conditional with many
-   GCC versions up to GCC 9.
+   This variant     (n1 < n2 ? -1 : n1 > n2)  produces a conditional jump with
+   many GCC versions up to GCC 9.
    The better code  (n1 > n2) - (n1 < n2)  from Hacker's Delight § 2-9
    avoids conditional jumps in all GCC versions >= 3.4.  */
 #define _GL_CMP(n1, n2) (((n1) > (n2)) - ((n1) < (n2)))
@@ -1571,13 +1562,25 @@ AC_DEFUN([gl_CHECK_FUNCS_CASE_FOR_MACOS],
              if test $[ac_cv_func_][$1] = yes; then
                [gl_cv_onwards_func_][$1]=yes
              else
+               dnl This is a bit complicated, because here we need the behaviour
+               dnl of AC_CHECK_DECL before the
+               dnl commit e1bbc9b93cdff61d70719c224b37970e065008bb (2025-05-26).
+               [ac_cv_have_decl_][$1][_saved]="$[ac_cv_have_decl_][$1]"
                unset [ac_cv_have_decl_][$1]
+               ac_c_future_darwin_options_saved="$ac_c_future_darwin_options"
+               ac_cxx_future_darwin_options_saved="$ac_cxx_future_darwin_options"
+               ac_c_future_darwin_options=
+               ac_cxx_future_darwin_options=
                AC_CHECK_DECL([$1], , , [$2])
+               ac_c_future_darwin_options="$ac_c_future_darwin_options_saved"
+               ac_cxx_future_darwin_options="$ac_cxx_future_darwin_options_saved"
                if test $[ac_cv_have_decl_][$1] = yes; then
                  [gl_cv_onwards_func_][$1]='future OS version'
                else
                  [gl_cv_onwards_func_][$1]=no
                fi
+               [ac_cv_have_decl_][$1]="$[ac_cv_have_decl_][$1][_saved]"
+               unset [ac_cv_have_decl_][$1][_saved]
              fi
            else
              AC_CHECK_FUNC([$1])
diff --git a/m4/gnulib-comp.m4 b/m4/gnulib-comp.m4
index 97db7d32a66..7e6a8a5494f 100644
--- a/m4/gnulib-comp.m4
+++ b/m4/gnulib-comp.m4
@@ -547,12 +547,7 @@ AC_DEFUN([gl_INIT],
   GL_STDC_LEADING_ZEROS=1
   AC_REQUIRE([gl_STDBIT_H])
   GL_STDC_TRAILING_ZEROS=1
-  AC_CHECK_HEADERS_ONCE([stdckdint.h])
-  if test $ac_cv_header_stdckdint_h = yes; then
-    GL_GENERATE_STDCKDINT_H=false
-  else
-    GL_GENERATE_STDCKDINT_H=true
-  fi
+  gl_STDCKDINT_H
   gl_CONDITIONAL_HEADER([stdckdint.h])
   AC_PROG_MKDIR_P
   gl_STDDEF_H
@@ -1558,6 +1553,7 @@ AC_DEFUN([gl_FILE_LIST], [
   m4/std-gnu11.m4
   m4/stdalign.m4
   m4/stdbit_h.m4
+  m4/stdckdint_h.m4
   m4/stddef_h.m4
   m4/stdint.m4
   m4/stdio_h.m4
diff --git a/m4/libgmp.m4 b/m4/libgmp.m4
index baed8ab1a0a..abf677949dd 100644
--- a/m4/libgmp.m4
+++ b/m4/libgmp.m4
@@ -1,5 +1,5 @@
 # libgmp.m4
-# serial 8
+# serial 9
 # Configure the GMP library or a replacement.
 dnl Copyright 2020-2025 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
@@ -34,7 +34,11 @@ AC_DEFUN([gl_LIBGMP],
               # include <gmp.h>
               #else
               # include <gmp/gmp.h>
-              #endif],
+              #endif
+              #if ! (6 < __GNU_MP_VERSION + (2 <= __GNU_MP_VERSION_MINOR))
+              # error "GMP < 6.2.0, so mpz_probab_prime_p lacks Baillie-PSW"
+              #endif
+              ],
              [static const mp_limb_t x[2] = { 0x73, 0x55 };
               mpz_t tmp;
               mpz_roinit_n (tmp, x, 2);
diff --git a/m4/open.m4 b/m4/open.m4
index 2bceddbdbe3..dd3a805f5e9 100644
--- a/m4/open.m4
+++ b/m4/open.m4
@@ -1,5 +1,5 @@
 # open.m4
-# serial 16
+# serial 17
 dnl Copyright (C) 2007-2025 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -10,6 +10,9 @@ AC_DEFUN([gl_FUNC_OPEN],
 [
   AC_REQUIRE([AC_CANONICAL_HOST])
   AC_REQUIRE([gl_PREPROC_O_CLOEXEC])
+  AC_REQUIRE([gl_FCNTL_O_FLAGS])
+  AS_CASE([$gl_cv_header_working_fcntl_h],
+    [*O_DIRECTORY* | *no], [REPLACE_OPEN=1])
   case "$host_os" in
     mingw* | windows* | pw*)
       REPLACE_OPEN=1
diff --git a/m4/stdckdint_h.m4 b/m4/stdckdint_h.m4
new file mode 100644
index 00000000000..d269faa5c92
--- /dev/null
+++ b/m4/stdckdint_h.m4
@@ -0,0 +1,136 @@
+# stdckdint_h.m4
+# serial 1
+dnl Copyright 2025 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.
+
+dnl Written by Collin Funk.
+
+AC_DEFUN_ONCE([gl_STDCKDINT_H],
+[
+  gl_CHECK_NEXT_HEADERS([stdckdint.h])
+  if test $ac_cv_header_stdckdint_h = yes; then
+    HAVE_STDCKDINT_H=1
+  else
+    HAVE_STDCKDINT_H=0
+  fi
+  AC_SUBST([HAVE_STDCKDINT_H])
+
+  if test $HAVE_STDCKDINT_H = 1; then
+    AC_CACHE_CHECK([whether stdckdint.h can be included in C],
+      [gl_cv_header_c_stdckdint_h],
+      [AC_COMPILE_IFELSE(
+         [AC_LANG_PROGRAM(
+            [[#include <stdckdint.h>
+            ]])],
+         [gl_cv_header_c_stdckdint_h=yes],
+         [gl_cv_header_c_stdckdint_h=no])])
+    if test $gl_cv_header_c_stdckdint_h = yes; then
+      HAVE_C_STDCKDINT_H=1
+      AC_CACHE_CHECK([checking for an ISO C23 compliant stdckdint.h in C],
+        [gl_cv_header_c_stdckdint_h_works],
+        [AC_COMPILE_IFELSE(
+           [AC_LANG_PROGRAM(
+              [[#include <stdckdint.h>
+              ]],
+              [[int r;
+                int a = 1;
+                int b = 1;
+                return !!(ckd_add (&r, a, b) || ckd_sub (&r, a, b)
+                          || ckd_mul (&r, a, b));
+              ]])],
+           [gl_cv_header_c_stdckdint_h_works=yes],
+           [gl_cv_header_c_stdckdint_h_works=no])])
+      if test $gl_cv_header_c_stdckdint_h_works = yes; then
+        HAVE_WORKING_C_STDCKDINT_H=1
+      else
+        HAVE_WORKING_C_STDCKDINT_H=0
+      fi
+    else
+      HAVE_C_STDCKDINT_H=0
+      HAVE_WORKING_C_STDCKDINT_H=0
+    fi
+    if test "$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
+         dnl an autoconf bug <https://savannah.gnu.org/support/?110294>.
+         cat > conftest.cpp <<\EOF
+#include <stdckdint.h>
+EOF
+         gl_command="$CXX $CXXFLAGS $CPPFLAGS -c conftest.cpp"
+         if AC_TRY_EVAL([gl_command]); then
+           gl_cv_header_cxx_stdckdint_h=yes
+         else
+           gl_cv_header_cxx_stdckdint_h=no
+         fi
+         rm -fr conftest*
+        ])
+      if test $gl_cv_header_cxx_stdckdint_h = yes; then
+        HAVE_CXX_STDCKDINT_H=1
+        AC_CACHE_CHECK([checking for an ISO C++26 compliant stdckdint.h in C++],
+          [gl_cv_header_cxx_stdckdint_h_works],
+          [dnl We can't use AC_LANG_PUSH([C++]) and AC_LANG_POP([C++]) here, due to
+           dnl an autoconf bug <https://savannah.gnu.org/support/?110294>.
+           cat > conftest.cpp <<\EOF
+#include <stdckdint.h>
+int
+main (void)
+{
+  int r;
+  int a = 1;
+  int b = 1;
+  return !!(ckd_add (&r, a, b) || ckd_sub (&r, a, b) || ckd_mul (&r, a, b));
+}
+EOF
+           gl_command="$CXX $CXXFLAGS $CPPFLAGS -c conftest.cpp"
+           if AC_TRY_EVAL([gl_command]); then
+             gl_cv_header_cxx_stdckdint_h_works=yes
+           else
+             gl_cv_header_cxx_stdckdint_h_works=no
+           fi
+           rm -fr conftest*
+          ])
+        if test $gl_cv_header_cxx_stdckdint_h_works = yes; then
+          HAVE_WORKING_CXX_STDCKDINT_H=1
+        else
+          HAVE_WORKING_CXX_STDCKDINT_H=0
+        fi
+      else
+        HAVE_CXX_STDCKDINT_H=0
+        HAVE_WORKING_CXX_STDCKDINT_H=0
+      fi
+    fi
+  else
+    HAVE_C_STDCKDINT_H=0
+    HAVE_WORKING_C_STDCKDINT_H=0
+    HAVE_CXX_STDCKDINT_H=0
+    HAVE_WORKING_CXX_STDCKDINT_H=0
+  fi
+  AC_SUBST([HAVE_C_STDCKDINT_H])
+  AC_SUBST([HAVE_WORKING_C_STDCKDINT_H])
+  AC_SUBST([HAVE_CXX_STDCKDINT_H])
+  AC_SUBST([HAVE_WORKING_CXX_STDCKDINT_H])
+
+  if test "$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 \
+       && test $HAVE_CXX_STDCKDINT_H = 1 \
+       && test $HAVE_WORKING_CXX_STDCKDINT_H = 1; then
+      GL_GENERATE_STDCKDINT_H=false
+    else
+      GL_GENERATE_STDCKDINT_H=true
+    fi
+  else
+    dnl We don't care about C++ here.
+    if test $HAVE_C_STDCKDINT_H = 1 \
+       && test $HAVE_WORKING_C_STDCKDINT_H = 1; then
+      GL_GENERATE_STDCKDINT_H=false
+    else
+      GL_GENERATE_STDCKDINT_H=true
+    fi
+  fi
+])
diff --git a/m4/stddef_h.m4 b/m4/stddef_h.m4
index 3bc8cd85fea..127ec05b60d 100644
--- a/m4/stddef_h.m4
+++ b/m4/stddef_h.m4
@@ -1,5 +1,5 @@
 # stddef_h.m4
-# serial 21
+# serial 23
 dnl Copyright (C) 2009-2025 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -64,20 +64,26 @@ AC_DEFUN_ONCE([gl_STDDEF_H],
     GL_GENERATE_STDDEF_H=true
   fi
 
-  AC_CACHE_CHECK([for unreachable],
-    [gl_cv_func_unreachable],
+  AC_CACHE_CHECK([for unreachable in C],
+    [gl_cv_c_func_unreachable],
     [AC_LINK_IFELSE(
        [AC_LANG_PROGRAM(
           [[#include <stddef.h>
           ]],
           [[unreachable ();
           ]])],
-       [gl_cv_func_unreachable=yes],
-       [gl_cv_func_unreachable=no])
+       [gl_cv_c_func_unreachable=yes],
+       [gl_cv_c_func_unreachable=no])
     ])
-  if test $gl_cv_func_unreachable = no; then
+  if test $gl_cv_c_func_unreachable = no; then
     GL_GENERATE_STDDEF_H=true
+    HAVE_C_UNREACHABLE=0
+  else
+    HAVE_C_UNREACHABLE=1
   fi
+  AC_SUBST([HAVE_C_UNREACHABLE])
+  dnl Provide gl_unreachable() unconditionally.
+  GL_GENERATE_STDDEF_H=true
 
   dnl https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114869
   AC_CACHE_CHECK([whether nullptr_t needs <stddef.h>],