Merging upstream version 2.12.1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 276 insertions, 220 deletions

diff --git a/gl/m4/printf.m4 b/gl/m4/printf.m4
index 8b8f010..bb67d59 100644
--- a/gl/m4/printf.m4
+++ b/gl/m4/printf.m4
@@ -1,5 +1,5 @@
-# printf.m4 serial 84
-dnl Copyright (C) 2003, 2007-2023 Free Software Foundation, Inc.
+# printf.m4 serial 89
+dnl Copyright (C) 2003, 2007-2024 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.
@@ -86,7 +86,8 @@ changequote(,)dnl
            linux*-android*)      gl_cv_func_printf_sizes_c99="guessing yes";;
 changequote([,])dnl
                                  # Guess yes on MSVC, no on mingw.
-           mingw*)               AC_EGREP_CPP([Known], [
+           windows*-msvc*)       gl_cv_func_printf_sizes_c99="guessing yes" ;;
+           mingw* | windows*)    AC_EGREP_CPP([Known], [
 #ifdef _MSC_VER
  Known
 #endif
@@ -179,7 +180,7 @@ int main ()
                                # Guess no on Android.
            linux*-android*)    gl_cv_func_printf_sizes_c23="guessing no";;
                                # Guess no on native Windows.
-           mingw*)             gl_cv_func_printf_sizes_c23="guessing no";;
+           mingw* | windows*)  gl_cv_func_printf_sizes_c23="guessing no";;
                                # If we don't know, obey --enable-cross-guesses.
            *)                  gl_cv_func_printf_sizes_c23="$gl_cross_guess_normal";;
          esac
@@ -223,20 +224,21 @@ int main ()
         [gl_cv_func_printf_long_double=yes],
         [gl_cv_func_printf_long_double=no],
         [case "$host_os" in
-                            # Guess no on BeOS.
-           beos*)           gl_cv_func_printf_long_double="guessing no";;
-                            # Guess yes on Android.
-           linux*-android*) gl_cv_func_printf_long_double="guessing yes";;
-                            # Guess yes on MSVC, no on mingw.
-           mingw*)          AC_EGREP_CPP([Known], [
+                              # Guess no on BeOS.
+           beos*)             gl_cv_func_printf_long_double="guessing no";;
+                              # Guess yes on Android.
+           linux*-android*)   gl_cv_func_printf_long_double="guessing yes";;
+                              # Guess yes on MSVC, no on mingw.
+           windows*-msvc*)    gl_cv_func_printf_long_double="guessing yes" ;;
+           mingw* | windows*) AC_EGREP_CPP([Known], [
 #ifdef _MSC_VER
  Known
 #endif
-                              ],
-                              [gl_cv_func_printf_long_double="guessing yes"],
-                              [gl_cv_func_printf_long_double="guessing no"])
-                            ;;
-           *)               gl_cv_func_printf_long_double="guessing yes";;
+                                ],
+                                [gl_cv_func_printf_long_double="guessing yes"],
+                                [gl_cv_func_printf_long_double="guessing no"])
+                              ;;
+           *)                 gl_cv_func_printf_long_double="guessing yes";;
          esac
         ])
     ])
@@ -354,7 +356,8 @@ changequote(,)dnl
            linux*-android*)      gl_cv_func_printf_infinite="guessing no";;
 changequote([,])dnl
                                  # Guess yes on MSVC, no on mingw.
-           mingw*)               AC_EGREP_CPP([Known], [
+           windows*-msvc*)       gl_cv_func_printf_infinite="guessing yes" ;;
+           mingw* | windows*)    AC_EGREP_CPP([Known], [
 #ifdef _MSC_VER
  Known
 #endif
@@ -568,7 +571,8 @@ changequote(,)dnl
                    linux*-android*)      gl_cv_func_printf_infinite_long_double="guessing no";;
 changequote([,])dnl
                                          # Guess yes on MSVC, no on mingw.
-                   mingw*)               AC_EGREP_CPP([Known], [
+                   windows*-msvc*)       gl_cv_func_printf_infinite_long_double="guessing yes" ;;
+                   mingw* | windows*)    AC_EGREP_CPP([Known], [
 #ifdef _MSC_VER
  Known
 #endif
@@ -681,7 +685,7 @@ int main ()
                                  # Guess no on Android.
            linux*-android*)      gl_cv_func_printf_directive_a="guessing no";;
                                  # Guess no on native Windows.
-           mingw*)               gl_cv_func_printf_directive_a="guessing no";;
+           mingw* | windows*)    gl_cv_func_printf_directive_a="guessing no";;
                                  # If we don't know, obey --enable-cross-guesses.
            *)                    gl_cv_func_printf_directive_a="$gl_cross_guess_normal";;
          esac
@@ -736,7 +740,7 @@ int main ()
                                # Guess no on Android.
            linux*-android*)    gl_cv_func_printf_directive_b="guessing no";;
                                # Guess no on native Windows.
-           mingw*)             gl_cv_func_printf_directive_b="guessing no";;
+           mingw* | windows*)  gl_cv_func_printf_directive_b="guessing no";;
                                # If we don't know, obey --enable-cross-guesses.
            *)                  gl_cv_func_printf_directive_b="$gl_cross_guess_normal";;
          esac
@@ -791,7 +795,7 @@ int main ()
                                # Guess no on Android.
            linux*-android*)    gl_cv_func_printf_directive_uppercase_b="guessing no";;
                                # Guess no on native Windows.
-           mingw*)             gl_cv_func_printf_directive_uppercase_b="guessing no";;
+           mingw* | windows*)  gl_cv_func_printf_directive_uppercase_b="guessing no";;
                                # If we don't know, obey --enable-cross-guesses.
            *)                  gl_cv_func_printf_directive_uppercase_b="$gl_cross_guess_normal";;
          esac
@@ -857,7 +861,8 @@ changequote(,)dnl
            linux*-android*)      gl_cv_func_printf_directive_f="guessing no";;
 changequote([,])dnl
                                  # Guess yes on MSVC, no on mingw.
-           mingw*)               AC_EGREP_CPP([Known], [
+           windows*-msvc*)       gl_cv_func_printf_directive_f="guessing yes" ;;
+           mingw* | windows*)    AC_EGREP_CPP([Known], [
 #ifdef _MSC_VER
  Known
 #endif
@@ -923,21 +928,21 @@ int main ()
         [gl_cv_func_printf_directive_n=yes],
         [gl_cv_func_printf_directive_n=no],
         [case "$host_os" in
-                            # Guess no on glibc when _FORTIFY_SOURCE >= 2.
-           *-gnu* | gnu*)   AC_COMPILE_IFELSE(
-                              [AC_LANG_SOURCE(
-                                 [[#if _FORTIFY_SOURCE >= 2
-                                    error fail
-                                   #endif
-                                 ]])],
-                              [gl_cv_func_printf_directive_n="guessing yes"],
-                              [gl_cv_func_printf_directive_n="guessing no"])
-                            ;;
-                            # Guess no on Android.
-           linux*-android*) gl_cv_func_printf_directive_n="guessing no";;
-                            # Guess no on native Windows.
-           mingw*)          gl_cv_func_printf_directive_n="guessing no";;
-           *)               gl_cv_func_printf_directive_n="guessing yes";;
+                              # Guess no on glibc when _FORTIFY_SOURCE >= 2.
+           *-gnu* | gnu*)     AC_COMPILE_IFELSE(
+                                [AC_LANG_SOURCE(
+                                   [[#if _FORTIFY_SOURCE >= 2
+                                      error fail
+                                     #endif
+                                   ]])],
+                                [gl_cv_func_printf_directive_n="guessing yes"],
+                                [gl_cv_func_printf_directive_n="guessing no"])
+                              ;;
+                              # Guess no on Android.
+           linux*-android*)   gl_cv_func_printf_directive_n="guessing no";;
+                              # Guess no on native Windows.
+           mingw* | windows*) gl_cv_func_printf_directive_n="guessing no";;
+           *)                 gl_cv_func_printf_directive_n="guessing yes";;
          esac
         ])
     ])
@@ -1007,18 +1012,18 @@ int main ()
         [
 changequote(,)dnl
          case "$host_os" in
-                            # Guess yes on OpenBSD >= 6.0.
-           openbsd[1-5].*)  gl_cv_func_printf_directive_ls="guessing no";;
-           openbsd*)        gl_cv_func_printf_directive_ls="guessing yes";;
-           irix*)           gl_cv_func_printf_directive_ls="guessing no";;
-           solaris*)        gl_cv_func_printf_directive_ls="guessing no";;
-           cygwin*)         gl_cv_func_printf_directive_ls="guessing no";;
-           beos* | haiku*)  gl_cv_func_printf_directive_ls="guessing no";;
-                            # Guess no on Android.
-           linux*-android*) gl_cv_func_printf_directive_ls="guessing no";;
-                            # Guess yes on native Windows.
-           mingw*)          gl_cv_func_printf_directive_ls="guessing yes";;
-           *)               gl_cv_func_printf_directive_ls="guessing yes";;
+                              # Guess yes on OpenBSD >= 6.0.
+           openbsd[1-5].*)    gl_cv_func_printf_directive_ls="guessing no";;
+           openbsd*)          gl_cv_func_printf_directive_ls="guessing yes";;
+           irix*)             gl_cv_func_printf_directive_ls="guessing no";;
+           solaris*)          gl_cv_func_printf_directive_ls="guessing no";;
+           cygwin*)           gl_cv_func_printf_directive_ls="guessing no";;
+           beos* | haiku*)    gl_cv_func_printf_directive_ls="guessing no";;
+                              # Guess no on Android.
+           linux*-android*)   gl_cv_func_printf_directive_ls="guessing no";;
+                              # Guess yes on native Windows.
+           mingw* | windows*) gl_cv_func_printf_directive_ls="guessing yes";;
+           *)                 gl_cv_func_printf_directive_ls="guessing yes";;
          esac
 changequote([,])dnl
         ])
@@ -1027,7 +1032,8 @@ changequote([,])dnl
 
 dnl Test whether the *printf family of functions supports the %lc format
 dnl directive and in particular, when the argument is a null wide character,
-dnl whether the functions don't produce a NUL byte.
+dnl whether the functions produce a NUL byte, as specified in ISO C 23
+dnl after the issue GB-141 was fixed.
 dnl Result is gl_cv_func_printf_directive_lc.
 
 AC_DEFUN([gl_PRINTF_DIRECTIVE_LC],
@@ -1046,13 +1052,11 @@ int main ()
 {
   int result = 0;
   char buf[100];
-  /* This test fails on glibc 2.35, FreeBSD 13.1, NetBSD 9.0, OpenBSD 7.2,
-     macOS 12.5, AIX 7.2, Solaris 11.4.
-     glibc 2.35 bug: <https://sourceware.org/bugzilla/show_bug.cgi?id=30257>  */
+  /* This test fails on musl libc 1.2.4.  */
   {
     buf[0] = '\0';
     if (sprintf (buf, "%lc%lc%lc", (wint_t) 'a', (wint_t) 0, (wint_t) 'z') < 0
-        || strcmp (buf, "az") != 0)
+        || memcmp (buf, "a\0z", 4) != 0)
       result |= 1;
   }
   return result;
@@ -1062,10 +1066,10 @@ int main ()
         [
 changequote(,)dnl
          case "$host_os" in
-                               # Guess yes on musl libc.
-           *-musl* | midipix*) gl_cv_func_printf_directive_lc="guessing yes";;
-                               # Guess no otherwise.
-           *)                  gl_cv_func_printf_directive_lc="guessing no";;
+                               # Guess no on musl libc.
+           *-musl* | midipix*) gl_cv_func_printf_directive_lc="guessing no";;
+                               # Guess yes otherwise.
+           *)                  gl_cv_func_printf_directive_lc="guessing yes";;
          esac
 changequote([,])dnl
         ])
@@ -1102,13 +1106,17 @@ int main ()
 changequote(,)dnl
          case "$host_os" in
            netbsd[1-3]* | netbsdelf[1-3]* | netbsdaout[1-3]* | netbsdcoff[1-3]*)
-                            gl_cv_func_printf_positions="guessing no";;
-           beos*)           gl_cv_func_printf_positions="guessing no";;
-                            # Guess yes on Android.
-           linux*-android*) gl_cv_func_printf_positions="guessing yes";;
-                            # Guess no on native Windows.
-           mingw* | pw*)    gl_cv_func_printf_positions="guessing no";;
-           *)               gl_cv_func_printf_positions="guessing yes";;
+             gl_cv_func_printf_positions="guessing no";;
+           beos*)
+             gl_cv_func_printf_positions="guessing no";;
+             # Guess yes on Android.
+           linux*-android*)
+             gl_cv_func_printf_positions="guessing yes";;
+             # Guess no on native Windows.
+           mingw* | windows* | pw*)
+             gl_cv_func_printf_positions="guessing no";;
+           *)
+             gl_cv_func_printf_positions="guessing yes";;
          esac
 changequote([,])dnl
         ])
@@ -1143,13 +1151,13 @@ int main ()
         [
 changequote(,)dnl
          case "$host_os" in
-           cygwin*)         gl_cv_func_printf_flag_grouping="guessing no";;
-           netbsd*)         gl_cv_func_printf_flag_grouping="guessing no";;
-                            # Guess no on Android.
-           linux*-android*) gl_cv_func_printf_flag_grouping="guessing no";;
-                            # Guess no on native Windows.
-           mingw* | pw*)    gl_cv_func_printf_flag_grouping="guessing no";;
-           *)               gl_cv_func_printf_flag_grouping="guessing yes";;
+           cygwin*)                 gl_cv_func_printf_flag_grouping="guessing no";;
+           netbsd*)                 gl_cv_func_printf_flag_grouping="guessing no";;
+                                    # Guess no on Android.
+           linux*-android*)         gl_cv_func_printf_flag_grouping="guessing no";;
+                                    # Guess no on native Windows.
+           mingw* | windows* | pw*) gl_cv_func_printf_flag_grouping="guessing no";;
+           *)                       gl_cv_func_printf_flag_grouping="guessing yes";;
          esac
 changequote([,])dnl
         ])
@@ -1186,16 +1194,16 @@ int main ()
         [
 changequote(,)dnl
          case "$host_os" in
-                            # Guess yes on HP-UX 11.
-           hpux11*)         gl_cv_func_printf_flag_leftadjust="guessing yes";;
-                            # Guess no on HP-UX 10 and older.
-           hpux*)           gl_cv_func_printf_flag_leftadjust="guessing no";;
-                            # Guess yes on Android.
-           linux*-android*) gl_cv_func_printf_flag_leftadjust="guessing yes";;
-                            # Guess yes on native Windows.
-           mingw*)          gl_cv_func_printf_flag_leftadjust="guessing yes";;
-                            # Guess yes otherwise.
-           *)               gl_cv_func_printf_flag_leftadjust="guessing yes";;
+                              # Guess yes on HP-UX 11.
+           hpux11*)           gl_cv_func_printf_flag_leftadjust="guessing yes";;
+                              # Guess no on HP-UX 10 and older.
+           hpux*)             gl_cv_func_printf_flag_leftadjust="guessing no";;
+                              # Guess yes on Android.
+           linux*-android*)   gl_cv_func_printf_flag_leftadjust="guessing yes";;
+                              # Guess yes on native Windows.
+           mingw* | windows*) gl_cv_func_printf_flag_leftadjust="guessing yes";;
+                              # Guess yes otherwise.
+           *)                 gl_cv_func_printf_flag_leftadjust="guessing yes";;
          esac
 changequote([,])dnl
         ])
@@ -1242,7 +1250,7 @@ changequote(,)dnl
                                # Guess no on Android.
            linux*-android*)    gl_cv_func_printf_flag_zero="guessing no";;
                                # Guess no on native Windows.
-           mingw*)             gl_cv_func_printf_flag_zero="guessing no";;
+           mingw* | windows*)  gl_cv_func_printf_flag_zero="guessing no";;
                                # If we don't know, obey --enable-cross-guesses.
            *)                  gl_cv_func_printf_flag_zero="$gl_cross_guess_normal";;
          esac
@@ -1251,6 +1259,50 @@ changequote([,])dnl
     ])
 ])
 
+dnl Test whether the *printf family of functions supports the # flag with a
+dnl zero precision and a zero value in the 'x' and 'X' directives correctly.
+dnl ISO C and POSIX specify that for the 'd', 'i', 'b', 'o', 'u', 'x', 'X'
+dnl directives: "The result of converting a zero value with a precision of
+dnl zero is no characters."  But on Mac OS X 10.5, for the 'x', 'X' directives,
+dnl when a # flag is present, the output is "0" instead of "".
+dnl Result is gl_cv_func_printf_flag_alt_precision_zero.
+
+AC_DEFUN([gl_PRINTF_FLAG_ALT_PRECISION_ZERO],
+[
+  AC_REQUIRE([AC_PROG_CC])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+  AC_CACHE_CHECK([whether printf supports the alternative flag with a zero precision],
+    [gl_cv_func_printf_flag_alt_precision_zero],
+    [
+      AC_RUN_IFELSE(
+        [AC_LANG_SOURCE([[
+#include <stdio.h>
+static char buf[10];
+int main ()
+{
+  int result = 0;
+  if (sprintf (buf, "%#.0x %d", 0, 33, 44) > 0 + 3)
+    result |= 1;
+  return result;
+}]])],
+        [gl_cv_func_printf_flag_alt_precision_zero=yes],
+        [gl_cv_func_printf_flag_alt_precision_zero=no],
+        [
+changequote(,)dnl
+         case "$host_os" in
+           # Guess no only on macOS 10..12 systems.
+           darwin[0-9] | darwin[0-9].* | \
+           darwin1[0-9] | darwin1[0-9].* | \
+           darwin2[0-1] | darwin2[0-1].*)
+                    gl_cv_func_printf_flag_alt_precision_zero="guessing no" ;;
+           darwin*) gl_cv_func_printf_flag_alt_precision_zero="guessing yes" ;;
+           *)       gl_cv_func_printf_flag_alt_precision_zero="guessing yes" ;;
+         esac
+changequote([,])dnl
+        ])
+    ])
+])
+
 dnl Test whether the *printf family of functions supports large precisions.
 dnl On mingw, precisions larger than 512 are treated like 512, in integer,
 dnl floating-point or pointer output. On Solaris 10/x86, precisions larger
@@ -1297,12 +1349,12 @@ int main ()
 changequote(,)dnl
          case "$host_os" in
            # Guess no only on Solaris, native Windows, and BeOS systems.
-           solaris*)        gl_cv_func_printf_precision="guessing no" ;;
-           mingw* | pw*)    gl_cv_func_printf_precision="guessing no" ;;
-           beos*)           gl_cv_func_printf_precision="guessing no" ;;
-                            # Guess yes on Android.
-           linux*-android*) gl_cv_func_printf_precision="guessing yes" ;;
-           *)               gl_cv_func_printf_precision="guessing yes" ;;
+           solaris*)                gl_cv_func_printf_precision="guessing no" ;;
+           mingw* | windows* | pw*) gl_cv_func_printf_precision="guessing no" ;;
+           beos*)                   gl_cv_func_printf_precision="guessing no" ;;
+                                    # Guess yes on Android.
+           linux*-android*)         gl_cv_func_printf_precision="guessing yes" ;;
+           *)                       gl_cv_func_printf_precision="guessing yes" ;;
          esac
 changequote([,])dnl
         ])
@@ -1518,7 +1570,7 @@ changequote(,)dnl
                                  # Guess yes on Android.
            linux*-android*)      gl_cv_func_snprintf_truncation_c99="guessing yes";;
                                  # Guess no on native Windows.
-           mingw*)               gl_cv_func_snprintf_truncation_c99="guessing no";;
+           mingw* | windows*)    gl_cv_func_snprintf_truncation_c99="guessing no";;
                                  # If we don't know, obey --enable-cross-guesses.
            *)                    gl_cv_func_snprintf_truncation_c99="$gl_cross_guess_normal";;
          esac
@@ -1615,7 +1667,8 @@ changequote(,)dnl
            linux*-android*)      gl_cv_func_snprintf_retval_c99="guessing yes";;
 changequote([,])dnl
                                  # Guess yes on MSVC, no on mingw.
-           mingw*)               AC_EGREP_CPP([Known], [
+           windows*-msvc*)       gl_cv_func_snprintf_retval_c99="guessing yes" ;;
+           mingw* | windows*)    AC_EGREP_CPP([Known], [
 #ifdef _MSC_VER
  Known
 #endif
@@ -1719,7 +1772,7 @@ changequote(,)dnl
                                  # Guess no on Android.
            linux*-android*)      gl_cv_func_snprintf_directive_n="guessing no";;
                                  # Guess no on native Windows.
-           mingw*)               gl_cv_func_snprintf_directive_n="guessing no";;
+           mingw* | windows*)    gl_cv_func_snprintf_directive_n="guessing no";;
                                  # If we don't know, obey --enable-cross-guesses.
            *)                    gl_cv_func_snprintf_directive_n="$gl_cross_guess_normal";;
 changequote([,])dnl
@@ -1767,11 +1820,11 @@ int main()
         [gl_cv_func_snprintf_size1=yes],
         [gl_cv_func_snprintf_size1=no],
         [case "$host_os" in
-                            # Guess yes on Android.
-           linux*-android*) gl_cv_func_snprintf_size1="guessing yes" ;;
-                            # Guess yes on native Windows.
-           mingw*)          gl_cv_func_snprintf_size1="guessing yes" ;;
-           *)               gl_cv_func_snprintf_size1="guessing yes" ;;
+                              # Guess yes on Android.
+           linux*-android*)   gl_cv_func_snprintf_size1="guessing yes" ;;
+                              # Guess yes on native Windows.
+           mingw* | windows*) gl_cv_func_snprintf_size1="guessing yes" ;;
+           *)                 gl_cv_func_snprintf_size1="guessing yes" ;;
          esac
         ])
     ])
@@ -1844,40 +1897,40 @@ int main()
         [
 changequote(,)dnl
          case "$host_os" in
-                                 # Guess yes on glibc systems.
-           *-gnu* | gnu*)        gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
-                                 # Guess yes on musl systems.
-           *-musl* | midipix*)   gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
-                                 # Guess yes on FreeBSD >= 5.
-           freebsd[1-4].*)       gl_cv_func_vsnprintf_zerosize_c99="guessing no";;
-           freebsd* | kfreebsd*) gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
-           midnightbsd*)         gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
-                                 # Guess yes on Mac OS X >= 10.3.
-           darwin[1-6].*)        gl_cv_func_vsnprintf_zerosize_c99="guessing no";;
-           darwin*)              gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
-                                 # Guess yes on Cygwin.
-           cygwin*)              gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
-                                 # Guess yes on Solaris >= 2.6.
+                                    # Guess yes on glibc systems.
+           *-gnu* | gnu*)           gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
+                                    # Guess yes on musl systems.
+           *-musl* | midipix*)      gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
+                                    # Guess yes on FreeBSD >= 5.
+           freebsd[1-4].*)          gl_cv_func_vsnprintf_zerosize_c99="guessing no";;
+           freebsd* | kfreebsd*)    gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
+           midnightbsd*)            gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
+                                    # Guess yes on Mac OS X >= 10.3.
+           darwin[1-6].*)           gl_cv_func_vsnprintf_zerosize_c99="guessing no";;
+           darwin*)                 gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
+                                    # Guess yes on Cygwin.
+           cygwin*)                 gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
+                                    # Guess yes on Solaris >= 2.6.
            solaris2.[0-5] | solaris2.[0-5].*)
-                                 gl_cv_func_vsnprintf_zerosize_c99="guessing no";;
-           solaris*)             gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
-                                 # Guess yes on AIX >= 4.
-           aix[1-3]*)            gl_cv_func_vsnprintf_zerosize_c99="guessing no";;
-           aix*)                 gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
-                                 # Guess yes on IRIX >= 6.5.
-           irix6.5)              gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
-                                 # Guess yes on NetBSD >= 3.
+                                    gl_cv_func_vsnprintf_zerosize_c99="guessing no";;
+           solaris*)                gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
+                                    # Guess yes on AIX >= 4.
+           aix[1-3]*)               gl_cv_func_vsnprintf_zerosize_c99="guessing no";;
+           aix*)                    gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
+                                    # Guess yes on IRIX >= 6.5.
+           irix6.5)                 gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
+                                    # Guess yes on NetBSD >= 3.
            netbsd[1-2]* | netbsdelf[1-2]* | netbsdaout[1-2]* | netbsdcoff[1-2]*)
-                                 gl_cv_func_vsnprintf_zerosize_c99="guessing no";;
-           netbsd*)              gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
-                                 # Guess yes on BeOS.
-           beos*)                gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
-                                 # Guess yes on Android.
-           linux*-android*)      gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
-                                 # Guess yes on native Windows.
-           mingw* | pw*)         gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
-                                 # If we don't know, obey --enable-cross-guesses.
-           *)                    gl_cv_func_vsnprintf_zerosize_c99="$gl_cross_guess_normal";;
+                                    gl_cv_func_vsnprintf_zerosize_c99="guessing no";;
+           netbsd*)                 gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
+                                    # Guess yes on BeOS.
+           beos*)                   gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
+                                    # Guess yes on Android.
+           linux*-android*)         gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
+                                    # Guess yes on native Windows.
+           mingw* | windows* | pw*) gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
+                                    # If we don't know, obey --enable-cross-guesses.
+           *)                       gl_cv_func_vsnprintf_zerosize_c99="$gl_cross_guess_normal";;
          esac
 changequote([,])dnl
         ])
@@ -1934,17 +1987,17 @@ int main()
         [gl_cv_func_swprintf_works=yes],
         [gl_cv_func_swprintf_works=no],
         [case "$host_os" in
-                               # Guess yes on glibc systems.
-           *-gnu* | gnu*)      gl_cv_func_swprintf_works="guessing yes";;
-                               # Guess no on musl systems.
-           *-musl* | midipix*) gl_cv_func_swprintf_works="guessing no";;
-                               # Guess no on FreeBSD, NetBSD, OpenBSD, macOS, AIX.
+                                    # Guess yes on glibc systems.
+           *-gnu* | gnu*)           gl_cv_func_swprintf_works="guessing yes";;
+                                    # Guess no on musl systems.
+           *-musl* | midipix*)      gl_cv_func_swprintf_works="guessing no";;
+                                    # Guess no on FreeBSD, NetBSD, OpenBSD, macOS, AIX.
            freebsd* | midnightbsd* | netbsd* | openbsd* | darwin* | aix*)
-                               gl_cv_func_swprintf_works="guessing no";;
-                               # Guess no on native Windows.
-           mingw* | pw*)       gl_cv_func_swprintf_works="guessing no";;
-                               # If we don't know, obey --enable-cross-guesses.
-           *)                  gl_cv_func_swprintf_works="$gl_cross_guess_normal";;
+                                    gl_cv_func_swprintf_works="guessing no";;
+                                    # Guess no on native Windows.
+           mingw* | windows* | pw*) gl_cv_func_swprintf_works="guessing no";;
+                                    # If we don't know, obey --enable-cross-guesses.
+           *)                       gl_cv_func_swprintf_works="$gl_cross_guess_normal";;
          esac
         ])
     ])
@@ -1983,7 +2036,7 @@ int main ()
         [gl_cv_func_swprintf_directive_la=yes],
         [gl_cv_func_swprintf_directive_la=no],
         [case "$host_os" in
-                                 # Guess yes on glibc >= 2.17 systems.
+                               # Guess yes on glibc >= 2.17 systems.
            *-gnu* | gnu*)
              AC_EGREP_CPP([Unlucky], [
                #include <features.h>
@@ -1996,14 +2049,14 @@ int main ()
                [gl_cv_func_swprintf_directive_la="guessing yes"],
                [gl_cv_func_swprintf_directive_la="guessing no"])
              ;;
-                                 # Guess yes on musl systems.
-           *-musl* | midipix*)   gl_cv_func_swprintf_directive_la="guessing yes";;
-                                 # Guess yes on Android.
-           linux*-android*)      gl_cv_func_swprintf_directive_la="guessing yes";;
-                                 # Guess no on native Windows.
-           mingw*)               gl_cv_func_swprintf_directive_la="guessing no";;
-                                 # If we don't know, obey --enable-cross-guesses.
-           *)                    gl_cv_func_swprintf_directive_la="$gl_cross_guess_normal";;
+                               # Guess yes on musl systems.
+           *-musl* | midipix*) gl_cv_func_swprintf_directive_la="guessing yes";;
+                               # Guess yes on Android.
+           linux*-android*)    gl_cv_func_swprintf_directive_la="guessing yes";;
+                               # Guess no on native Windows.
+           mingw* | windows*)  gl_cv_func_swprintf_directive_la="guessing no";;
+                               # If we don't know, obey --enable-cross-guesses.
+           *)                  gl_cv_func_swprintf_directive_la="$gl_cross_guess_normal";;
          esac
         ])
     ])
@@ -2040,16 +2093,16 @@ int main ()
         [gl_cv_func_swprintf_directive_lc=yes],
         [gl_cv_func_swprintf_directive_lc=no],
         [case "$host_os" in
-                                 # Guess yes on glibc systems.
-           *-gnu* | gnu*)        gl_cv_func_swprintf_directive_lc="guessing yes";;
-                                 # Guess no on musl systems.
-           *-musl* | midipix*)   gl_cv_func_swprintf_directive_lc="guessing no";;
-                                 # Guess no on Android.
-           linux*-android*)      gl_cv_func_swprintf_directive_lc="guessing no";;
-                                 # Guess yes on native Windows.
-           mingw*)               gl_cv_func_swprintf_directive_lc="guessing yes";;
-                                 # If we don't know, obey --enable-cross-guesses.
-           *)                    gl_cv_func_swprintf_directive_lc="$gl_cross_guess_normal";;
+                               # Guess yes on glibc systems.
+           *-gnu* | gnu*)      gl_cv_func_swprintf_directive_lc="guessing yes";;
+                               # Guess no on musl systems.
+           *-musl* | midipix*) gl_cv_func_swprintf_directive_lc="guessing no";;
+                               # Guess no on Android.
+           linux*-android*)    gl_cv_func_swprintf_directive_lc="guessing no";;
+                               # Guess yes on native Windows.
+           mingw* | windows*)  gl_cv_func_swprintf_directive_lc="guessing yes";;
+                               # If we don't know, obey --enable-cross-guesses.
+           *)                  gl_cv_func_swprintf_directive_lc="$gl_cross_guess_normal";;
          esac
         ])
     ])
@@ -2073,17 +2126,18 @@ dnl 13 = gl_PRINTF_POSITIONS
 dnl 14 = gl_PRINTF_FLAG_GROUPING
 dnl 15 = gl_PRINTF_FLAG_LEFTADJUST
 dnl 16 = gl_PRINTF_FLAG_ZERO
-dnl 17 = gl_PRINTF_PRECISION
-dnl 18 = gl_PRINTF_ENOMEM
-dnl 19 = gl_SNPRINTF_PRESENCE
-dnl 20 = gl_SNPRINTF_TRUNCATION_C99
-dnl 21 = gl_SNPRINTF_RETVAL_C99
-dnl 22 = gl_SNPRINTF_DIRECTIVE_N
-dnl 23 = gl_SNPRINTF_SIZE1
-dnl 24 = gl_VSNPRINTF_ZEROSIZE_C99
-dnl 25 = gl_SWPRINTF_WORKS
-dnl 26 = gl_SWPRINTF_DIRECTIVE_LA
-dnl 27 = gl_SWPRINTF_DIRECTIVE_LC
+dnl 17 = gl_PRINTF_FLAG_ALT_PRECISION_ZERO
+dnl 18 = gl_PRINTF_PRECISION
+dnl 19 = gl_PRINTF_ENOMEM
+dnl 20 = gl_SNPRINTF_PRESENCE
+dnl 21 = gl_SNPRINTF_TRUNCATION_C99
+dnl 22 = gl_SNPRINTF_RETVAL_C99
+dnl 23 = gl_SNPRINTF_DIRECTIVE_N
+dnl 24 = gl_SNPRINTF_SIZE1
+dnl 25 = gl_VSNPRINTF_ZEROSIZE_C99
+dnl 26 = gl_SWPRINTF_WORKS
+dnl 27 = gl_SWPRINTF_DIRECTIVE_LA
+dnl 28 = gl_SWPRINTF_DIRECTIVE_LC
 dnl
 dnl 1 = checking whether printf supports size specifiers as in C99...
 dnl 2 = checking whether printf supports size specifiers as in C23...
@@ -2101,58 +2155,60 @@ dnl 13 = checking whether printf supports POSIX/XSI format strings with position
 dnl 14 = checking whether printf supports the grouping flag...
 dnl 15 = checking whether printf supports the left-adjust flag correctly...
 dnl 16 = checking whether printf supports the zero flag correctly...
-dnl 17 = checking whether printf supports large precisions...
-dnl 18 = checking whether printf survives out-of-memory conditions...
-dnl 19 = checking for snprintf...
-dnl 20 = checking whether snprintf truncates the result as in C99...
-dnl 21 = checking whether snprintf returns a byte count as in C99...
-dnl 22 = checking whether snprintf fully supports the 'n' directive...
-dnl 23 = checking whether snprintf respects a size of 1...
-dnl 24 = checking whether vsnprintf respects a zero size as in C99...
-dnl 25 = checking whether swprintf works...
-dnl 26 = checking whether swprintf supports the 'La' and 'LA' directives...
-dnl 27 = checking whether swprintf supports the 'lc' directive...
+dnl 17 = checking whether printf supports the alternative flag with a zero precision...
+dnl 18 = checking whether printf supports large precisions...
+dnl 19 = checking whether printf survives out-of-memory conditions...
+dnl 20 = checking for snprintf...
+dnl 21 = checking whether snprintf truncates the result as in C99...
+dnl 22 = checking whether snprintf returns a byte count as in C99...
+dnl 23 = checking whether snprintf fully supports the 'n' directive...
+dnl 24 = checking whether snprintf respects a size of 1...
+dnl 25 = checking whether vsnprintf respects a zero size as in C99...
+dnl 26 = checking whether swprintf works...
+dnl 27 = checking whether swprintf supports the 'La' and 'LA' directives...
+dnl 28 = checking whether swprintf supports the 'lc' directive...
 dnl
 dnl . = yes, # = no.
 dnl
-dnl                                  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
-dnl   musl libc 1.2.3                .  #  .  .  .  .  #  #  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  #  .  #
-dnl   glibc 2.35                     .  #  .  .  .  .  .  .  .  .  .  #  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .
-dnl   glibc 2.5                      .  #  .  .  .  .  #  #  .  .  .  #  .  .  .  .  .  .  .  .  .  .  .  .  .  #  .
-dnl   glibc 2.3.6                    .  #  .  .  .  #  #  #  .  .  .  #  .  .  .  .  .  .  .  .  .  .  .  .  .  #  .
-dnl   FreeBSD 13.0                   .  #  .  .  .  #  #  #  .  .  .  #  .  .  .  .  .  #  .  .  .  .  .  .  #  .  #
-dnl   FreeBSD 5.4, 6.1               .  #  .  .  .  #  #  #  .  .  .  #  .  .  .  #  .  #  .  .  .  .  .  .  #  ?  ?
-dnl   Mac OS X 10.13.5               .  #  .  .  #  #  #  #  .  #  .  #  .  .  .  .  .  .  .  .  .  #  .  .  #  ?  ?
-dnl   Mac OS X 10.5.8                .  #  .  .  #  #  #  #  .  .  .  #  .  .  .  #  .  .  .  .  .  .  .  .  #  ?  ?
-dnl   Mac OS X 10.3.9                .  #  .  .  .  #  #  #  .  .  .  #  .  .  .  #  .  #  .  .  .  .  .  .  #  ?  ?
-dnl   OpenBSD 6.0, 6.7               .  #  .  .  .  #  #  #  .  .  .  #  .  .  .  .  .  #  .  .  .  .  .  .  #  .  #
-dnl   OpenBSD 3.9, 4.0               .  #  .  #  #  #  #  #  #  .  #  #  .  #  .  #  .  #  .  .  .  .  .  .  #  ?  ?
-dnl   Cygwin 1.7.0 (2009)            .  #  .  .  #  .  #  #  .  .  ?  ?  .  .  .  .  .  ?  .  .  .  .  .  .  ?  ?  ?
-dnl   Cygwin 1.5.25 (2008)           .  #  .  .  #  #  #  #  .  .  #  ?  .  .  .  .  .  #  .  .  .  .  .  .  ?  ?  ?
-dnl   Cygwin 1.5.19 (2006)           #  #  .  .  #  #  #  #  #  .  #  ?  .  #  .  #  #  #  .  .  .  .  .  .  ?  ?  ?
-dnl   Solaris 11.4                   .  #  .  #  #  #  #  #  .  .  #  #  .  .  .  #  .  .  .  .  .  .  .  .  .  #  .
-dnl   Solaris 11.3                   .  #  .  .  .  #  #  #  .  .  #  #  .  .  .  .  .  .  .  .  .  .  .  .  .  #  .
-dnl   Solaris 11.0                   .  #  .  #  #  #  #  #  .  .  #  #  .  .  .  #  .  .  .  .  .  .  .  .  ?  ?  ?
-dnl   Solaris 10                     .  #  .  #  #  #  #  #  .  .  #  #  .  .  .  #  #  .  .  .  .  .  .  .  .  #  .
-dnl   Solaris 2.6 ... 9              #  #  .  #  #  #  #  #  #  .  #  #  .  .  .  #  #  .  .  .  #  .  .  .  ?  ?  ?
-dnl   Solaris 2.5.1                  #  #  .  #  #  #  #  #  #  .  #  #  .  .  .  #  .  .  #  #  #  #  #  #  ?  ?  ?
-dnl   AIX 7.1                        .  #  .  #  #  #  #  #  .  .  .  #  .  .  .  #  #  .  .  .  .  .  .  .  #  .  .
-dnl   AIX 5.2                        .  #  .  #  #  #  #  #  .  .  .  #  .  .  .  #  .  .  .  .  .  .  .  .  #  ?  ?
-dnl   AIX 4.3.2, 5.1                 #  #  .  #  #  #  #  #  #  .  .  #  .  .  .  #  .  .  .  .  #  .  .  .  #  ?  ?
-dnl   HP-UX 11.31                    .  #  .  .  .  #  #  #  .  .  .  ?  .  .  .  #  .  .  .  .  #  #  .  .  ?  ?  ?
-dnl   HP-UX 11.{00,11,23}            #  #  .  .  .  #  #  #  #  .  .  ?  .  .  .  #  .  .  .  .  #  #  .  #  ?  ?  ?
-dnl   HP-UX 10.20                    #  #  .  #  .  #  #  #  #  .  ?  ?  .  .  #  #  .  .  .  .  #  #  ?  #  ?  ?  ?
-dnl   IRIX 6.5                       #  #  .  #  #  #  #  #  #  .  #  #  .  .  .  #  .  .  .  .  #  .  .  .  #  ?  ?
-dnl   OSF/1 5.1                      #  #  .  #  #  #  #  #  #  .  .  ?  .  .  .  #  .  .  .  .  #  .  .  #  ?  ?  ?
-dnl   OSF/1 4.0d                     #  #  .  #  #  #  #  #  #  .  .  ?  .  .  .  #  .  .  #  #  #  #  #  #  ?  ?  ?
-dnl   NetBSD 9.0                     .  #  .  .  .  #  #  #  .  .  .  #  .  .  .  .  .  .  .  .  .  .  .  .  #  .  #
-dnl   NetBSD 5.0                     .  #  .  .  #  #  #  #  .  .  .  #  .  .  .  #  .  #  .  .  .  .  .  .  #  ?  ?
-dnl   NetBSD 4.0                     .  #  ?  ?  ?  ?  #  #  ?  .  ?  #  .  ?  ?  ?  ?  ?  .  .  .  ?  ?  ?  #  ?  ?
-dnl   NetBSD 3.0                     .  #  .  .  .  #  #  #  #  .  ?  #  #  #  ?  #  .  #  .  .  .  .  .  .  #  ?  ?
-dnl   Haiku                          .  #  .  .  #  #  #  #  #  .  #  ?  .  .  .  .  .  ?  .  .  ?  .  .  .  .  #  .
-dnl   BeOS                           #  #  #  .  #  #  #  #  #  .  ?  ?  #  .  ?  .  #  ?  .  .  ?  .  .  .  ?  ?  ?
-dnl   Android 4.3                    .  #  .  #  #  #  #  #  #  #  #  ?  .  #  .  #  .  #  .  .  .  #  .  .  ?  ?  ?
-dnl   old mingw / msvcrt             #  #  #  #  #  #  #  #  #  .  .  ?  #  #  .  #  #  ?  .  #  #  #  .  .  #  ?  ?
-dnl   MSVC 9                         #  #  #  #  #  #  #  #  #  #  .  ?  #  #  .  #  #  ?  #  #  #  #  .  .  #  ?  ?
-dnl   mingw 2009-2011                .  #  #  .  #  .  #  #  .  .  .  ?  #  #  .  .  .  ?  .  .  .  .  .  .  #  ?  ?
-dnl   mingw-w64 2011                 #  #  #  #  #  #  #  #  #  .  .  ?  #  #  .  #  #  ?  .  #  #  #  .  .  #  ?  ?
+dnl                                  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
+dnl   musl libc 1.2.3                .  #  .  .  .  .  #  #  .  .  .  #  .  .  .  .  ?  .  .  .  .  .  .  .  .  #  .  #
+dnl   glibc 2.35                     .  #  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .
+dnl   glibc 2.5                      .  #  .  .  .  .  #  #  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  #  .
+dnl   glibc 2.3.6                    .  #  .  .  .  #  #  #  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  #  .
+dnl   FreeBSD 14.0                   .  .  .  .  .  #  .  .  .  .  .  .  .  .  .  .  .  .  #  .  .  .  .  .  .  #  .  #
+dnl   FreeBSD 13.0                   .  #  .  .  .  #  #  #  .  .  .  .  .  .  .  .  .  .  #  .  .  .  .  .  .  #  .  #
+dnl   FreeBSD 5.4, 6.1               .  #  .  .  .  #  #  #  .  .  .  .  .  .  .  #  ?  .  #  .  .  .  .  .  .  #  ?  ?
+dnl   Mac OS X 10.13.5               .  #  .  .  #  #  #  #  .  #  .  .  .  .  .  .  .  .  .  .  .  .  #  .  .  #  ?  ?
+dnl   Mac OS X 10.5.8                .  #  .  .  #  #  #  #  .  .  .  .  .  .  .  #  #  .  .  .  .  .  .  .  .  #  ?  ?
+dnl   Mac OS X 10.3.9                .  #  .  .  .  #  #  #  .  .  .  .  .  .  .  #  #  .  #  .  .  .  .  .  .  #  ?  ?
+dnl   OpenBSD 6.0, 6.7               .  #  .  .  .  #  #  #  .  .  .  .  .  .  .  .  .  .  #  .  .  .  .  .  .  #  .  #
+dnl   OpenBSD 3.9, 4.0               .  #  .  #  #  #  #  #  #  .  #  .  .  #  .  #  ?  .  #  .  .  .  .  .  .  #  ?  ?
+dnl   Cygwin 1.7.0 (2009)            .  #  .  .  #  .  #  #  .  .  ?  ?  .  .  .  .  ?  .  ?  .  .  .  .  .  .  ?  ?  ?
+dnl   Cygwin 1.5.25 (2008)           .  #  .  .  #  #  #  #  .  .  #  ?  .  .  .  .  ?  .  #  .  .  .  .  .  .  ?  ?  ?
+dnl   Cygwin 1.5.19 (2006)           #  #  .  .  #  #  #  #  #  .  #  ?  .  #  .  #  ?  #  #  .  .  .  .  .  .  ?  ?  ?
+dnl   Solaris 11.4                   .  #  .  #  #  #  #  #  .  .  #  .  .  .  .  #  .  .  .  .  .  .  .  .  .  .  #  .
+dnl   Solaris 11.3                   .  #  .  .  .  #  #  #  .  .  #  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  #  .
+dnl   Solaris 11.0                   .  #  .  #  #  #  #  #  .  .  #  .  .  .  .  #  .  .  .  .  .  .  .  .  .  ?  ?  ?
+dnl   Solaris 10                     .  #  .  #  #  #  #  #  .  .  #  .  .  .  .  #  .  #  .  .  .  .  .  .  .  .  #  .
+dnl   Solaris 2.6 ... 9              #  #  .  #  #  #  #  #  #  .  #  .  .  .  .  #  ?  #  .  .  .  #  .  .  .  ?  ?  ?
+dnl   Solaris 2.5.1                  #  #  .  #  #  #  #  #  #  .  #  .  .  .  .  #  ?  .  .  #  #  #  #  #  #  ?  ?  ?
+dnl   AIX 7.1                        .  #  .  #  #  #  #  #  .  .  .  .  .  .  .  #  .  #  .  .  .  .  .  .  .  #  .  .
+dnl   AIX 5.2                        .  #  .  #  #  #  #  #  .  .  .  .  .  .  .  #  ?  .  .  .  .  .  .  .  .  #  ?  ?
+dnl   AIX 4.3.2, 5.1                 #  #  .  #  #  #  #  #  #  .  .  .  .  .  .  #  ?  .  .  .  .  #  .  .  .  #  ?  ?
+dnl   HP-UX 11.31                    .  #  .  .  .  #  #  #  .  .  .  ?  .  .  .  #  ?  .  .  .  .  #  #  .  .  ?  ?  ?
+dnl   HP-UX 11.{00,11,23}            #  #  .  .  .  #  #  #  #  .  .  ?  .  .  .  #  ?  .  .  .  .  #  #  .  #  ?  ?  ?
+dnl   HP-UX 10.20                    #  #  .  #  .  #  #  #  #  .  ?  ?  .  .  #  #  ?  .  .  .  .  #  #  ?  #  ?  ?  ?
+dnl   IRIX 6.5                       #  #  .  #  #  #  #  #  #  .  #  .  .  .  .  #  ?  .  .  .  .  #  .  .  .  #  ?  ?
+dnl   OSF/1 5.1                      #  #  .  #  #  #  #  #  #  .  .  ?  .  .  .  #  ?  .  .  .  .  #  .  .  #  ?  ?  ?
+dnl   OSF/1 4.0d                     #  #  .  #  #  #  #  #  #  .  .  ?  .  .  .  #  ?  .  .  #  #  #  #  #  #  ?  ?  ?
+dnl   NetBSD 9.0                     .  #  .  .  .  #  #  #  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  #  .  #
+dnl   NetBSD 5.0                     .  #  .  .  #  #  #  #  .  .  .  .  .  .  .  #  ?  .  #  .  .  .  .  .  .  #  ?  ?
+dnl   NetBSD 4.0                     .  #  ?  ?  ?  ?  #  #  ?  .  ?  .  .  ?  ?  ?  ?  ?  ?  .  .  .  ?  ?  ?  #  ?  ?
+dnl   NetBSD 3.0                     .  #  .  .  .  #  #  #  #  .  ?  .  #  #  ?  #  ?  .  #  .  .  .  .  .  .  #  ?  ?
+dnl   Haiku                          .  #  .  .  #  #  #  #  #  .  #  ?  .  .  .  .  ?  .  ?  .  .  ?  .  .  .  .  #  .
+dnl   BeOS                           #  #  #  .  #  #  #  #  #  .  ?  ?  #  .  ?  .  ?  #  ?  .  .  ?  .  .  .  ?  ?  ?
+dnl   Android 4.3                    .  #  .  #  #  #  #  #  #  #  #  ?  .  #  .  #  ?  .  #  .  .  .  #  .  .  ?  ?  ?
+dnl   old mingw / msvcrt             #  #  #  #  #  #  #  #  #  .  .  ?  #  #  .  #  ?  #  ?  .  #  #  #  .  .  #  ?  ?
+dnl   MSVC 9                         #  #  #  #  #  #  #  #  #  #  .  ?  #  #  .  #  ?  #  ?  #  #  #  #  .  .  #  ?  ?
+dnl   mingw 2009-2011                .  #  #  .  #  .  #  #  .  .  .  ?  #  #  .  .  ?  .  ?  .  .  .  .  .  .  #  ?  ?
+dnl   mingw-w64 2011                 #  #  #  #  #  #  #  #  #  .  .  ?  #  #  .  #  ?  #  ?  .  #  #  #  .  .  #  ?  ?