# generated automatically by aclocal 1.16.5 -*- Autoconf -*-

# Copyright (C) 1996-2021 Free Software Foundation, Inc.

# This file is free software; the Free Software Foundation
# gives unlimited permission to copy and/or distribute it,
# with or without modifications, as long as this notice is preserved.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY, to the extent permitted by law; without
# even the implied warranty of MERCHANTABILITY or FITNESS FOR A
# PARTICULAR PURPOSE.

m4_ifndef([AC_CONFIG_MACRO_DIRS], [m4_defun([_AM_CONFIG_MACRO_DIRS], [])m4_defun([AC_CONFIG_MACRO_DIRS], [_AM_CONFIG_MACRO_DIRS($@)])])
# ===========================================================================
#        https://www.gnu.org/software/autoconf-archive/ax_pthread.html
# ===========================================================================
#
# SYNOPSIS
#
#   AX_PTHREAD([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]])
#
# DESCRIPTION
#
#   This macro figures out how to build C programs using POSIX threads. It
#   sets the PTHREAD_LIBS output variable to the threads library and linker
#   flags, and the PTHREAD_CFLAGS output variable to any special C compiler
#   flags that are needed. (The user can also force certain compiler
#   flags/libs to be tested by setting these environment variables.)
#
#   Also sets PTHREAD_CC and PTHREAD_CXX to any special C compiler that is
#   needed for multi-threaded programs (defaults to the value of CC
#   respectively CXX otherwise). (This is necessary on e.g. AIX to use the
#   special cc_r/CC_r compiler alias.)
#
#   NOTE: You are assumed to not only compile your program with these flags,
#   but also to link with them as well. For example, you might link with
#   $PTHREAD_CC $CFLAGS $PTHREAD_CFLAGS $LDFLAGS ... $PTHREAD_LIBS $LIBS
#   $PTHREAD_CXX $CXXFLAGS $PTHREAD_CFLAGS $LDFLAGS ... $PTHREAD_LIBS $LIBS
#
#   If you are only building threaded programs, you may wish to use these
#   variables in your default LIBS, CFLAGS, and CC:
#
#     LIBS="$PTHREAD_LIBS $LIBS"
#     CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
#     CXXFLAGS="$CXXFLAGS $PTHREAD_CFLAGS"
#     CC="$PTHREAD_CC"
#     CXX="$PTHREAD_CXX"
#
#   In addition, if the PTHREAD_CREATE_JOINABLE thread-attribute constant
#   has a nonstandard name, this macro defines PTHREAD_CREATE_JOINABLE to
#   that name (e.g. PTHREAD_CREATE_UNDETACHED on AIX).
#
#   Also HAVE_PTHREAD_PRIO_INHERIT is defined if pthread is found and the
#   PTHREAD_PRIO_INHERIT symbol is defined when compiling with
#   PTHREAD_CFLAGS.
#
#   ACTION-IF-FOUND is a list of shell commands to run if a threads library
#   is found, and ACTION-IF-NOT-FOUND is a list of commands to run it if it
#   is not found. If ACTION-IF-FOUND is not specified, the default action
#   will define HAVE_PTHREAD.
#
#   Please let the authors know if this macro fails on any platform, or if
#   you have any other suggestions or comments. This macro was based on work
#   by SGJ on autoconf scripts for FFTW (http://www.fftw.org/) (with help
#   from M. Frigo), as well as ac_pthread and hb_pthread macros posted by
#   Alejandro Forero Cuervo to the autoconf macro repository. We are also
#   grateful for the helpful feedback of numerous users.
#
#   Updated for Autoconf 2.68 by Daniel Richard G.
#
# LICENSE
#
#   Copyright (c) 2008 Steven G. Johnson <stevenj@alum.mit.edu>
#   Copyright (c) 2011 Daniel Richard G. <skunk@iSKUNK.ORG>
#   Copyright (c) 2019 Marc Stevens <marc.stevens@cwi.nl>
#
#   This program is free software: you can redistribute it and/or modify it
#   under the terms of the GNU General Public License as published by the
#   Free Software Foundation, either version 3 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 General
#   Public License for more details.
#
#   You should have received a copy of the GNU General Public License along
#   with this program. If not, see <https://www.gnu.org/licenses/>.
#
#   As a special exception, the respective Autoconf Macro's copyright owner
#   gives unlimited permission to copy, distribute and modify the configure
#   scripts that are the output of Autoconf when processing the Macro. You
#   need not follow the terms of the GNU General Public License when using
#   or distributing such scripts, even though portions of the text of the
#   Macro appear in them. The GNU General Public License (GPL) does govern
#   all other use of the material that constitutes the Autoconf Macro.
#
#   This special exception to the GPL applies to versions of the Autoconf
#   Macro released by the Autoconf Archive. When you make and distribute a
#   modified version of the Autoconf Macro, you may extend this special
#   exception to the GPL to apply to your modified version as well.

#serial 31

AU_ALIAS([ACX_PTHREAD], [AX_PTHREAD])
AC_DEFUN([AX_PTHREAD], [
AC_REQUIRE([AC_CANONICAL_HOST])
AC_REQUIRE([AC_PROG_CC])
AC_REQUIRE([AC_PROG_SED])
AC_LANG_PUSH([C])
ax_pthread_ok=no

# We used to check for pthread.h first, but this fails if pthread.h
# requires special compiler flags (e.g. on Tru64 or Sequent).
# It gets checked for in the link test anyway.

# First of all, check if the user has set any of the PTHREAD_LIBS,
# etcetera environment variables, and if threads linking works using
# them:
if test "x$PTHREAD_CFLAGS$PTHREAD_LIBS" != "x"; then
        ax_pthread_save_CC="$CC"
        ax_pthread_save_CFLAGS="$CFLAGS"
        ax_pthread_save_LIBS="$LIBS"
        AS_IF([test "x$PTHREAD_CC" != "x"], [CC="$PTHREAD_CC"])
        AS_IF([test "x$PTHREAD_CXX" != "x"], [CXX="$PTHREAD_CXX"])
        CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
        LIBS="$PTHREAD_LIBS $LIBS"
        AC_MSG_CHECKING([for pthread_join using $CC $PTHREAD_CFLAGS $PTHREAD_LIBS])
        AC_LINK_IFELSE([AC_LANG_CALL([], [pthread_join])], [ax_pthread_ok=yes])
        AC_MSG_RESULT([$ax_pthread_ok])
        if test "x$ax_pthread_ok" = "xno"; then
                PTHREAD_LIBS=""
                PTHREAD_CFLAGS=""
        fi
        CC="$ax_pthread_save_CC"
        CFLAGS="$ax_pthread_save_CFLAGS"
        LIBS="$ax_pthread_save_LIBS"
fi

# We must check for the threads library under a number of different
# names; the ordering is very important because some systems
# (e.g. DEC) have both -lpthread and -lpthreads, where one of the
# libraries is broken (non-POSIX).

# Create a list of thread flags to try. Items with a "," contain both
# C compiler flags (before ",") and linker flags (after ","). Other items
# starting with a "-" are C compiler flags, and remaining items are
# library names, except for "none" which indicates that we try without
# any flags at all, and "pthread-config" which is a program returning
# the flags for the Pth emulation library.

ax_pthread_flags="pthreads none -Kthread -pthread -pthreads -mthreads pthread --thread-safe -mt pthread-config"

# The ordering *is* (sometimes) important.  Some notes on the
# individual items follow:

# pthreads: AIX (must check this before -lpthread)
# none: in case threads are in libc; should be tried before -Kthread and
#       other compiler flags to prevent continual compiler warnings
# -Kthread: Sequent (threads in libc, but -Kthread needed for pthread.h)
# -pthread: Linux/gcc (kernel threads), BSD/gcc (userland threads), Tru64
#           (Note: HP C rejects this with "bad form for `-t' option")
# -pthreads: Solaris/gcc (Note: HP C also rejects)
# -mt: Sun Workshop C (may only link SunOS threads [-lthread], but it
#      doesn't hurt to check since this sometimes defines pthreads and
#      -D_REENTRANT too), HP C (must be checked before -lpthread, which
#      is present but should not be used directly; and before -mthreads,
#      because the compiler interprets this as "-mt" + "-hreads")
# -mthreads: Mingw32/gcc, Lynx/gcc
# pthread: Linux, etcetera
# --thread-safe: KAI C++
# pthread-config: use pthread-config program (for GNU Pth library)

case $host_os in

        freebsd*)

        # -kthread: FreeBSD kernel threads (preferred to -pthread since SMP-able)
        # lthread: LinuxThreads port on FreeBSD (also preferred to -pthread)

        ax_pthread_flags="-kthread lthread $ax_pthread_flags"
        ;;

        hpux*)

        # From the cc(1) man page: "[-mt] Sets various -D flags to enable
        # multi-threading and also sets -lpthread."

        ax_pthread_flags="-mt -pthread pthread $ax_pthread_flags"
        ;;

        openedition*)

        # IBM z/OS requires a feature-test macro to be defined in order to
        # enable POSIX threads at all, so give the user a hint if this is
        # not set. (We don't define these ourselves, as they can affect
        # other portions of the system API in unpredictable ways.)

        AC_EGREP_CPP([AX_PTHREAD_ZOS_MISSING],
            [
#            if !defined(_OPEN_THREADS) && !defined(_UNIX03_THREADS)
             AX_PTHREAD_ZOS_MISSING
#            endif
            ],
            [AC_MSG_WARN([IBM z/OS requires -D_OPEN_THREADS or -D_UNIX03_THREADS to enable pthreads support.])])
        ;;

        solaris*)

        # On Solaris (at least, for some versions), libc contains stubbed
        # (non-functional) versions of the pthreads routines, so link-based
        # tests will erroneously succeed. (N.B.: The stubs are missing
        # pthread_cleanup_push, or rather a function called by this macro,
        # so we could check for that, but who knows whether they'll stub
        # that too in a future libc.)  So we'll check first for the
        # standard Solaris way of linking pthreads (-mt -lpthread).

        ax_pthread_flags="-mt,-lpthread pthread $ax_pthread_flags"
        ;;
esac

# Are we compiling with Clang?

AC_CACHE_CHECK([whether $CC is Clang],
    [ax_cv_PTHREAD_CLANG],
    [ax_cv_PTHREAD_CLANG=no
     # Note that Autoconf sets GCC=yes for Clang as well as GCC
     if test "x$GCC" = "xyes"; then
        AC_EGREP_CPP([AX_PTHREAD_CC_IS_CLANG],
            [/* Note: Clang 2.7 lacks __clang_[a-z]+__ */
#            if defined(__clang__) && defined(__llvm__)
             AX_PTHREAD_CC_IS_CLANG
#            endif
            ],
            [ax_cv_PTHREAD_CLANG=yes])
     fi
    ])
ax_pthread_clang="$ax_cv_PTHREAD_CLANG"


# GCC generally uses -pthread, or -pthreads on some platforms (e.g. SPARC)

# Note that for GCC and Clang -pthread generally implies -lpthread,
# except when -nostdlib is passed.
# This is problematic using libtool to build C++ shared libraries with pthread:
# [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=25460
# [2] https://bugzilla.redhat.com/show_bug.cgi?id=661333
# [3] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=468555
# To solve this, first try -pthread together with -lpthread for GCC

AS_IF([test "x$GCC" = "xyes"],
      [ax_pthread_flags="-pthread,-lpthread -pthread -pthreads $ax_pthread_flags"])

# Clang takes -pthread (never supported any other flag), but we'll try with -lpthread first

AS_IF([test "x$ax_pthread_clang" = "xyes"],
      [ax_pthread_flags="-pthread,-lpthread -pthread"])


# The presence of a feature test macro requesting re-entrant function
# definitions is, on some systems, a strong hint that pthreads support is
# correctly enabled

case $host_os in
        darwin* | hpux* | linux* | osf* | solaris*)
        ax_pthread_check_macro="_REENTRANT"
        ;;

        aix*)
        ax_pthread_check_macro="_THREAD_SAFE"
        ;;

        *)
        ax_pthread_check_macro="--"
        ;;
esac
AS_IF([test "x$ax_pthread_check_macro" = "x--"],
      [ax_pthread_check_cond=0],
      [ax_pthread_check_cond="!defined($ax_pthread_check_macro)"])


if test "x$ax_pthread_ok" = "xno"; then
for ax_pthread_try_flag in $ax_pthread_flags; do

        case $ax_pthread_try_flag in
                none)
                AC_MSG_CHECKING([whether pthreads work without any flags])
                ;;

                *,*)
                PTHREAD_CFLAGS=`echo $ax_pthread_try_flag | sed "s/^\(.*\),\(.*\)$/\1/"`
                PTHREAD_LIBS=`echo $ax_pthread_try_flag | sed "s/^\(.*\),\(.*\)$/\2/"`
                AC_MSG_CHECKING([whether pthreads work with "$PTHREAD_CFLAGS" and "$PTHREAD_LIBS"])
                ;;

                -*)
                AC_MSG_CHECKING([whether pthreads work with $ax_pthread_try_flag])
                PTHREAD_CFLAGS="$ax_pthread_try_flag"
                ;;

                pthread-config)
                AC_CHECK_PROG([ax_pthread_config], [pthread-config], [yes], [no])
                AS_IF([test "x$ax_pthread_config" = "xno"], [continue])
                PTHREAD_CFLAGS="`pthread-config --cflags`"
                PTHREAD_LIBS="`pthread-config --ldflags` `pthread-config --libs`"
                ;;

                *)
                AC_MSG_CHECKING([for the pthreads library -l$ax_pthread_try_flag])
                PTHREAD_LIBS="-l$ax_pthread_try_flag"
                ;;
        esac

        ax_pthread_save_CFLAGS="$CFLAGS"
        ax_pthread_save_LIBS="$LIBS"
        CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
        LIBS="$PTHREAD_LIBS $LIBS"

        # Check for various functions.  We must include pthread.h,
        # since some functions may be macros.  (On the Sequent, we
        # need a special flag -Kthread to make this header compile.)
        # We check for pthread_join because it is in -lpthread on IRIX
        # while pthread_create is in libc.  We check for pthread_attr_init
        # due to DEC craziness with -lpthreads.  We check for
        # pthread_cleanup_push because it is one of the few pthread
        # functions on Solaris that doesn't have a non-functional libc stub.
        # We try pthread_create on general principles.

        AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <pthread.h>
#                       if $ax_pthread_check_cond
#                        error "$ax_pthread_check_macro must be defined"
#                       endif
                        static void *some_global = NULL;
                        static void routine(void *a)
                          {
                             /* To avoid any unused-parameter or
                                unused-but-set-parameter warning.  */
                             some_global = a;
                          }
                        static void *start_routine(void *a) { return a; }],
                       [pthread_t th; pthread_attr_t attr;
                        pthread_create(&th, 0, start_routine, 0);
                        pthread_join(th, 0);
                        pthread_attr_init(&attr);
                        pthread_cleanup_push(routine, 0);
                        pthread_cleanup_pop(0) /* ; */])],
            [ax_pthread_ok=yes],
            [])

        CFLAGS="$ax_pthread_save_CFLAGS"
        LIBS="$ax_pthread_save_LIBS"

        AC_MSG_RESULT([$ax_pthread_ok])
        AS_IF([test "x$ax_pthread_ok" = "xyes"], [break])

        PTHREAD_LIBS=""
        PTHREAD_CFLAGS=""
done
fi


# Clang needs special handling, because older versions handle the -pthread
# option in a rather... idiosyncratic way

if test "x$ax_pthread_clang" = "xyes"; then

        # Clang takes -pthread; it has never supported any other flag

        # (Note 1: This will need to be revisited if a system that Clang
        # supports has POSIX threads in a separate library.  This tends not
        # to be the way of modern systems, but it's conceivable.)

        # (Note 2: On some systems, notably Darwin, -pthread is not needed
        # to get POSIX threads support; the API is always present and
        # active.  We could reasonably leave PTHREAD_CFLAGS empty.  But
        # -pthread does define _REENTRANT, and while the Darwin headers
        # ignore this macro, third-party headers might not.)

        # However, older versions of Clang make a point of warning the user
        # that, in an invocation where only linking and no compilation is
        # taking place, the -pthread option has no effect ("argument unused
        # during compilation").  They expect -pthread to be passed in only
        # when source code is being compiled.
        #
        # Problem is, this is at odds with the way Automake and most other
        # C build frameworks function, which is that the same flags used in
        # compilation (CFLAGS) are also used in linking.  Many systems
        # supported by AX_PTHREAD require exactly this for POSIX threads
        # support, and in fact it is often not straightforward to specify a
        # flag that is used only in the compilation phase and not in
        # linking.  Such a scenario is extremely rare in practice.
        #
        # Even though use of the -pthread flag in linking would only print
        # a warning, this can be a nuisance for well-run software projects
        # that build with -Werror.  So if the active version of Clang has
        # this misfeature, we search for an option to squash it.

        AC_CACHE_CHECK([whether Clang needs flag to prevent "argument unused" warning when linking with -pthread],
            [ax_cv_PTHREAD_CLANG_NO_WARN_FLAG],
            [ax_cv_PTHREAD_CLANG_NO_WARN_FLAG=unknown
             # Create an alternate version of $ac_link that compiles and
             # links in two steps (.c -> .o, .o -> exe) instead of one
             # (.c -> exe), because the warning occurs only in the second
             # step
             ax_pthread_save_ac_link="$ac_link"
             ax_pthread_sed='s/conftest\.\$ac_ext/conftest.$ac_objext/g'
             ax_pthread_link_step=`AS_ECHO(["$ac_link"]) | sed "$ax_pthread_sed"`
             ax_pthread_2step_ac_link="($ac_compile) && (echo ==== >&5) && ($ax_pthread_link_step)"
             ax_pthread_save_CFLAGS="$CFLAGS"
             for ax_pthread_try in '' -Qunused-arguments -Wno-unused-command-line-argument unknown; do
                AS_IF([test "x$ax_pthread_try" = "xunknown"], [break])
                CFLAGS="-Werror -Wunknown-warning-option $ax_pthread_try -pthread $ax_pthread_save_CFLAGS"
                ac_link="$ax_pthread_save_ac_link"
                AC_LINK_IFELSE([AC_LANG_SOURCE([[int main(void){return 0;}]])],
                    [ac_link="$ax_pthread_2step_ac_link"
                     AC_LINK_IFELSE([AC_LANG_SOURCE([[int main(void){return 0;}]])],
                         [break])
                    ])
             done
             ac_link="$ax_pthread_save_ac_link"
             CFLAGS="$ax_pthread_save_CFLAGS"
             AS_IF([test "x$ax_pthread_try" = "x"], [ax_pthread_try=no])
             ax_cv_PTHREAD_CLANG_NO_WARN_FLAG="$ax_pthread_try"
            ])

        case "$ax_cv_PTHREAD_CLANG_NO_WARN_FLAG" in
                no | unknown) ;;
                *) PTHREAD_CFLAGS="$ax_cv_PTHREAD_CLANG_NO_WARN_FLAG $PTHREAD_CFLAGS" ;;
        esac

fi # $ax_pthread_clang = yes



# Various other checks:
if test "x$ax_pthread_ok" = "xyes"; then
        ax_pthread_save_CFLAGS="$CFLAGS"
        ax_pthread_save_LIBS="$LIBS"
        CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
        LIBS="$PTHREAD_LIBS $LIBS"

        # Detect AIX lossage: JOINABLE attribute is called UNDETACHED.
        AC_CACHE_CHECK([for joinable pthread attribute],
            [ax_cv_PTHREAD_JOINABLE_ATTR],
            [ax_cv_PTHREAD_JOINABLE_ATTR=unknown
             for ax_pthread_attr in PTHREAD_CREATE_JOINABLE PTHREAD_CREATE_UNDETACHED; do
                 AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <pthread.h>],
                                                 [int attr = $ax_pthread_attr; return attr /* ; */])],
                                [ax_cv_PTHREAD_JOINABLE_ATTR=$ax_pthread_attr; break],
                                [])
             done
            ])
        AS_IF([test "x$ax_cv_PTHREAD_JOINABLE_ATTR" != "xunknown" && \
               test "x$ax_cv_PTHREAD_JOINABLE_ATTR" != "xPTHREAD_CREATE_JOINABLE" && \
               test "x$ax_pthread_joinable_attr_defined" != "xyes"],
              [AC_DEFINE_UNQUOTED([PTHREAD_CREATE_JOINABLE],
                                  [$ax_cv_PTHREAD_JOINABLE_ATTR],
                                  [Define to necessary symbol if this constant
                                   uses a non-standard name on your system.])
               ax_pthread_joinable_attr_defined=yes
              ])

        AC_CACHE_CHECK([whether more special flags are required for pthreads],
            [ax_cv_PTHREAD_SPECIAL_FLAGS],
            [ax_cv_PTHREAD_SPECIAL_FLAGS=no
             case $host_os in
             solaris*)
             ax_cv_PTHREAD_SPECIAL_FLAGS="-D_POSIX_PTHREAD_SEMANTICS"
             ;;
             esac
            ])
        AS_IF([test "x$ax_cv_PTHREAD_SPECIAL_FLAGS" != "xno" && \
               test "x$ax_pthread_special_flags_added" != "xyes"],
              [PTHREAD_CFLAGS="$ax_cv_PTHREAD_SPECIAL_FLAGS $PTHREAD_CFLAGS"
               ax_pthread_special_flags_added=yes])

        AC_CACHE_CHECK([for PTHREAD_PRIO_INHERIT],
            [ax_cv_PTHREAD_PRIO_INHERIT],
            [AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <pthread.h>]],
                                             [[int i = PTHREAD_PRIO_INHERIT;
                                               return i;]])],
                            [ax_cv_PTHREAD_PRIO_INHERIT=yes],
                            [ax_cv_PTHREAD_PRIO_INHERIT=no])
            ])
        AS_IF([test "x$ax_cv_PTHREAD_PRIO_INHERIT" = "xyes" && \
               test "x$ax_pthread_prio_inherit_defined" != "xyes"],
              [AC_DEFINE([HAVE_PTHREAD_PRIO_INHERIT], [1], [Have PTHREAD_PRIO_INHERIT.])
               ax_pthread_prio_inherit_defined=yes
              ])

        CFLAGS="$ax_pthread_save_CFLAGS"
        LIBS="$ax_pthread_save_LIBS"

        # More AIX lossage: compile with *_r variant
        if test "x$GCC" != "xyes"; then
            case $host_os in
                aix*)
                AS_CASE(["x/$CC"],
                    [x*/c89|x*/c89_128|x*/c99|x*/c99_128|x*/cc|x*/cc128|x*/xlc|x*/xlc_v6|x*/xlc128|x*/xlc128_v6],
                    [#handle absolute path differently from PATH based program lookup
                     AS_CASE(["x$CC"],
                         [x/*],
                         [
			   AS_IF([AS_EXECUTABLE_P([${CC}_r])],[PTHREAD_CC="${CC}_r"])
			   AS_IF([test "x${CXX}" != "x"], [AS_IF([AS_EXECUTABLE_P([${CXX}_r])],[PTHREAD_CXX="${CXX}_r"])])
			 ],
                         [
			   AC_CHECK_PROGS([PTHREAD_CC],[${CC}_r],[$CC])
			   AS_IF([test "x${CXX}" != "x"], [AC_CHECK_PROGS([PTHREAD_CXX],[${CXX}_r],[$CXX])])
			 ]
                     )
                    ])
                ;;
            esac
        fi
fi

test -n "$PTHREAD_CC" || PTHREAD_CC="$CC"
test -n "$PTHREAD_CXX" || PTHREAD_CXX="$CXX"

AC_SUBST([PTHREAD_LIBS])
AC_SUBST([PTHREAD_CFLAGS])
AC_SUBST([PTHREAD_CC])
AC_SUBST([PTHREAD_CXX])

# Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND:
if test "x$ax_pthread_ok" = "xyes"; then
        ifelse([$1],,[AC_DEFINE([HAVE_PTHREAD],[1],[Define if you have POSIX threads libraries and header files.])],[$1])
        :
else
        ax_pthread_ok=no
        $2
fi
AC_LANG_POP
])dnl AX_PTHREAD

# host-cpu-c-abi.m4 serial 13
dnl Copyright (C) 2002-2020 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 From Bruno Haible and Sam Steingold.

dnl Sets the HOST_CPU variable to the canonical name of the CPU.
dnl Sets the HOST_CPU_C_ABI variable to the canonical name of the CPU with its
dnl C language ABI (application binary interface).
dnl Also defines __${HOST_CPU}__ and __${HOST_CPU_C_ABI}__ as C macros in
dnl config.h.
dnl
dnl This canonical name can be used to select a particular assembly language
dnl source file that will interoperate with C code on the given host.
dnl
dnl For example:
dnl * 'i386' and 'sparc' are different canonical names, because code for i386
dnl   will not run on SPARC CPUs and vice versa. They have different
dnl   instruction sets.
dnl * 'sparc' and 'sparc64' are different canonical names, because code for
dnl   'sparc' and code for 'sparc64' cannot be linked together: 'sparc' code
dnl   contains 32-bit instructions, whereas 'sparc64' code contains 64-bit
dnl   instructions. A process on a SPARC CPU can be in 32-bit mode or in 64-bit
dnl   mode, but not both.
dnl * 'mips' and 'mipsn32' are different canonical names, because they use
dnl   different argument passing and return conventions for C functions, and
dnl   although the instruction set of 'mips' is a large subset of the
dnl   instruction set of 'mipsn32'.
dnl * 'mipsn32' and 'mips64' are different canonical names, because they use
dnl   different sizes for the C types like 'int' and 'void *', and although
dnl   the instruction sets of 'mipsn32' and 'mips64' are the same.
dnl * The same canonical name is used for different endiannesses. You can
dnl   determine the endianness through preprocessor symbols:
dnl   - 'arm': test __ARMEL__.
dnl   - 'mips', 'mipsn32', 'mips64': test _MIPSEB vs. _MIPSEL.
dnl   - 'powerpc64': test _BIG_ENDIAN vs. _LITTLE_ENDIAN.
dnl * The same name 'i386' is used for CPUs of type i386, i486, i586
dnl   (Pentium), AMD K7, Pentium II, Pentium IV, etc., because
dnl   - Instructions that do not exist on all of these CPUs (cmpxchg,
dnl     MMX, SSE, SSE2, 3DNow! etc.) are not frequently used. If your
dnl     assembly language source files use such instructions, you will
dnl     need to make the distinction.
dnl   - Speed of execution of the common instruction set is reasonable across
dnl     the entire family of CPUs. If you have assembly language source files
dnl     that are optimized for particular CPU types (like GNU gmp has), you
dnl     will need to make the distinction.
dnl   See <https://en.wikipedia.org/wiki/X86_instruction_listings>.
AC_DEFUN([gl_HOST_CPU_C_ABI],
[
  AC_REQUIRE([AC_CANONICAL_HOST])
  AC_REQUIRE([gl_C_ASM])
  AC_CACHE_CHECK([host CPU and C ABI], [gl_cv_host_cpu_c_abi],
    [case "$host_cpu" in

changequote(,)dnl
       i[34567]86 )
changequote([,])dnl
         gl_cv_host_cpu_c_abi=i386
         ;;

       x86_64 )
         # On x86_64 systems, the C compiler may be generating code in one of
         # these ABIs:
         # - 64-bit instruction set, 64-bit pointers, 64-bit 'long': x86_64.
         # - 64-bit instruction set, 64-bit pointers, 32-bit 'long': x86_64
         #   with native Windows (mingw, MSVC).
         # - 64-bit instruction set, 32-bit pointers, 32-bit 'long': x86_64-x32.
         # - 32-bit instruction set, 32-bit pointers, 32-bit 'long': i386.
         AC_COMPILE_IFELSE(
           [AC_LANG_SOURCE(
              [[#if (defined __x86_64__ || defined __amd64__ \
                     || defined _M_X64 || defined _M_AMD64)
                 int ok;
                #else
                 error fail
                #endif
              ]])],
           [AC_COMPILE_IFELSE(
              [AC_LANG_SOURCE(
                 [[#if defined __ILP32__ || defined _ILP32
                    int ok;
                   #else
                    error fail
                   #endif
                 ]])],
              [gl_cv_host_cpu_c_abi=x86_64-x32],
              [gl_cv_host_cpu_c_abi=x86_64])],
           [gl_cv_host_cpu_c_abi=i386])
         ;;

changequote(,)dnl
       alphaev[4-8] | alphaev56 | alphapca5[67] | alphaev6[78] )
changequote([,])dnl
         gl_cv_host_cpu_c_abi=alpha
         ;;

       arm* | aarch64 )
         # Assume arm with EABI.
         # On arm64 systems, the C compiler may be generating code in one of
         # these ABIs:
         # - aarch64 instruction set, 64-bit pointers, 64-bit 'long': arm64.
         # - aarch64 instruction set, 32-bit pointers, 32-bit 'long': arm64-ilp32.
         # - 32-bit instruction set, 32-bit pointers, 32-bit 'long': arm or armhf.
         AC_COMPILE_IFELSE(
           [AC_LANG_SOURCE(
              [[#ifdef __aarch64__
                 int ok;
                #else
                 error fail
                #endif
              ]])],
           [AC_COMPILE_IFELSE(
              [AC_LANG_SOURCE(
                [[#if defined __ILP32__ || defined _ILP32
                   int ok;
                  #else
                   error fail
                  #endif
                ]])],
              [gl_cv_host_cpu_c_abi=arm64-ilp32],
              [gl_cv_host_cpu_c_abi=arm64])],
           [# Don't distinguish little-endian and big-endian arm, since they
            # don't require different machine code for simple operations and
            # since the user can distinguish them through the preprocessor
            # defines __ARMEL__ vs. __ARMEB__.
            # But distinguish arm which passes floating-point arguments and
            # return values in integer registers (r0, r1, ...) - this is
            # gcc -mfloat-abi=soft or gcc -mfloat-abi=softfp - from arm which
            # passes them in float registers (s0, s1, ...) and double registers
            # (d0, d1, ...) - this is gcc -mfloat-abi=hard. GCC 4.6 or newer
            # sets the preprocessor defines __ARM_PCS (for the first case) and
            # __ARM_PCS_VFP (for the second case), but older GCC does not.
            echo 'double ddd; void func (double dd) { ddd = dd; }' > conftest.c
            # Look for a reference to the register d0 in the .s file.
            AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS $gl_c_asm_opt conftest.c) >/dev/null 2>&1
            if LC_ALL=C grep 'd0,' conftest.$gl_asmext >/dev/null; then
              gl_cv_host_cpu_c_abi=armhf
            else
              gl_cv_host_cpu_c_abi=arm
            fi
            rm -f conftest*
           ])
         ;;

       hppa1.0 | hppa1.1 | hppa2.0* | hppa64 )
         # On hppa, the C compiler may be generating 32-bit code or 64-bit
         # code. In the latter case, it defines _LP64 and __LP64__.
         AC_COMPILE_IFELSE(
           [AC_LANG_SOURCE(
              [[#ifdef __LP64__
                 int ok;
                #else
                 error fail
                #endif
              ]])],
           [gl_cv_host_cpu_c_abi=hppa64],
           [gl_cv_host_cpu_c_abi=hppa])
         ;;

       ia64* )
         # On ia64 on HP-UX, the C compiler may be generating 64-bit code or
         # 32-bit code. In the latter case, it defines _ILP32.
         AC_COMPILE_IFELSE(
           [AC_LANG_SOURCE(
              [[#ifdef _ILP32
                 int ok;
                #else
                 error fail
                #endif
              ]])],
           [gl_cv_host_cpu_c_abi=ia64-ilp32],
           [gl_cv_host_cpu_c_abi=ia64])
         ;;

       mips* )
         # We should also check for (_MIPS_SZPTR == 64), but gcc keeps this
         # at 32.
         AC_COMPILE_IFELSE(
           [AC_LANG_SOURCE(
              [[#if defined _MIPS_SZLONG && (_MIPS_SZLONG == 64)
                 int ok;
                #else
                 error fail
                #endif
              ]])],
           [gl_cv_host_cpu_c_abi=mips64],
           [# In the n32 ABI, _ABIN32 is defined, _ABIO32 is not defined (but
            # may later get defined by <sgidefs.h>), and _MIPS_SIM == _ABIN32.
            # In the 32 ABI, _ABIO32 is defined, _ABIN32 is not defined (but
            # may later get defined by <sgidefs.h>), and _MIPS_SIM == _ABIO32.
            AC_COMPILE_IFELSE(
              [AC_LANG_SOURCE(
                 [[#if (_MIPS_SIM == _ABIN32)
                    int ok;
                   #else
                    error fail
                   #endif
                 ]])],
              [gl_cv_host_cpu_c_abi=mipsn32],
              [gl_cv_host_cpu_c_abi=mips])])
         ;;

       powerpc* )
         # Different ABIs are in use on AIX vs. Mac OS X vs. Linux,*BSD.
         # No need to distinguish them here; the caller may distinguish
         # them based on the OS.
         # On powerpc64 systems, the C compiler may still be generating
         # 32-bit code. And on powerpc-ibm-aix systems, the C compiler may
         # be generating 64-bit code.
         AC_COMPILE_IFELSE(
           [AC_LANG_SOURCE(
              [[#if defined __powerpc64__ || defined _ARCH_PPC64
                 int ok;
                #else
                 error fail
                #endif
              ]])],
           [# On powerpc64, there are two ABIs on Linux: The AIX compatible
            # one and the ELFv2 one. The latter defines _CALL_ELF=2.
            AC_COMPILE_IFELSE(
              [AC_LANG_SOURCE(
                 [[#if defined _CALL_ELF && _CALL_ELF == 2
                    int ok;
                   #else
                    error fail
                   #endif
                 ]])],
              [gl_cv_host_cpu_c_abi=powerpc64-elfv2],
              [gl_cv_host_cpu_c_abi=powerpc64])
           ],
           [gl_cv_host_cpu_c_abi=powerpc])
         ;;

       rs6000 )
         gl_cv_host_cpu_c_abi=powerpc
         ;;

       riscv32 | riscv64 )
         # There are 2 architectures (with variants): rv32* and rv64*.
         AC_COMPILE_IFELSE(
           [AC_LANG_SOURCE(
              [[#if __riscv_xlen == 64
                  int ok;
                #else
                  error fail
                #endif
              ]])],
           [cpu=riscv64],
           [cpu=riscv32])
         # There are 6 ABIs: ilp32, ilp32f, ilp32d, lp64, lp64f, lp64d.
         # Size of 'long' and 'void *':
         AC_COMPILE_IFELSE(
           [AC_LANG_SOURCE(
              [[#if defined __LP64__
                  int ok;
                #else
                  error fail
                #endif
              ]])],
           [main_abi=lp64],
           [main_abi=ilp32])
         # Float ABIs:
         # __riscv_float_abi_double:
         #   'float' and 'double' are passed in floating-point registers.
         # __riscv_float_abi_single:
         #   'float' are passed in floating-point registers.
         # __riscv_float_abi_soft:
         #   No values are passed in floating-point registers.
         AC_COMPILE_IFELSE(
           [AC_LANG_SOURCE(
              [[#if defined __riscv_float_abi_double
                  int ok;
                #else
                  error fail
                #endif
              ]])],
           [float_abi=d],
           [AC_COMPILE_IFELSE(
              [AC_LANG_SOURCE(
                 [[#if defined __riscv_float_abi_single
                     int ok;
                   #else
                     error fail
                   #endif
                 ]])],
              [float_abi=f],
              [float_abi=''])
           ])
         gl_cv_host_cpu_c_abi="${cpu}-${main_abi}${float_abi}"
         ;;

       s390* )
         # On s390x, the C compiler may be generating 64-bit (= s390x) code
         # or 31-bit (= s390) code.
         AC_COMPILE_IFELSE(
           [AC_LANG_SOURCE(
              [[#if defined __LP64__ || defined __s390x__
                  int ok;
                #else
                  error fail
                #endif
              ]])],
           [gl_cv_host_cpu_c_abi=s390x],
           [gl_cv_host_cpu_c_abi=s390])
         ;;

       sparc | sparc64 )
         # UltraSPARCs running Linux have `uname -m` = "sparc64", but the
         # C compiler still generates 32-bit code.
         AC_COMPILE_IFELSE(
           [AC_LANG_SOURCE(
              [[#if defined __sparcv9 || defined __arch64__
                 int ok;
                #else
                 error fail
                #endif
              ]])],
           [gl_cv_host_cpu_c_abi=sparc64],
           [gl_cv_host_cpu_c_abi=sparc])
         ;;

       *)
         gl_cv_host_cpu_c_abi="$host_cpu"
         ;;
     esac
    ])

  dnl In most cases, $HOST_CPU and $HOST_CPU_C_ABI are the same.
  HOST_CPU=`echo "$gl_cv_host_cpu_c_abi" | sed -e 's/-.*//'`
  HOST_CPU_C_ABI="$gl_cv_host_cpu_c_abi"
  AC_SUBST([HOST_CPU])
  AC_SUBST([HOST_CPU_C_ABI])

  # This was
  #   AC_DEFINE_UNQUOTED([__${HOST_CPU}__])
  #   AC_DEFINE_UNQUOTED([__${HOST_CPU_C_ABI}__])
  # earlier, but KAI C++ 3.2d doesn't like this.
  sed -e 's/-/_/g' >> confdefs.h <<EOF
#ifndef __${HOST_CPU}__
#define __${HOST_CPU}__ 1
#endif
#ifndef __${HOST_CPU_C_ABI}__
#define __${HOST_CPU_C_ABI}__ 1
#endif
EOF
  AH_TOP([/* CPU and C ABI indicator */
#ifndef __i386__
#undef __i386__
#endif
#ifndef __x86_64_x32__
#undef __x86_64_x32__
#endif
#ifndef __x86_64__
#undef __x86_64__
#endif
#ifndef __alpha__
#undef __alpha__
#endif
#ifndef __arm__
#undef __arm__
#endif
#ifndef __armhf__
#undef __armhf__
#endif
#ifndef __arm64_ilp32__
#undef __arm64_ilp32__
#endif
#ifndef __arm64__
#undef __arm64__
#endif
#ifndef __hppa__
#undef __hppa__
#endif
#ifndef __hppa64__
#undef __hppa64__
#endif
#ifndef __ia64_ilp32__
#undef __ia64_ilp32__
#endif
#ifndef __ia64__
#undef __ia64__
#endif
#ifndef __m68k__
#undef __m68k__
#endif
#ifndef __mips__
#undef __mips__
#endif
#ifndef __mipsn32__
#undef __mipsn32__
#endif
#ifndef __mips64__
#undef __mips64__
#endif
#ifndef __powerpc__
#undef __powerpc__
#endif
#ifndef __powerpc64__
#undef __powerpc64__
#endif
#ifndef __powerpc64_elfv2__
#undef __powerpc64_elfv2__
#endif
#ifndef __riscv32__
#undef __riscv32__
#endif
#ifndef __riscv64__
#undef __riscv64__
#endif
#ifndef __riscv32_ilp32__
#undef __riscv32_ilp32__
#endif
#ifndef __riscv32_ilp32f__
#undef __riscv32_ilp32f__
#endif
#ifndef __riscv32_ilp32d__
#undef __riscv32_ilp32d__
#endif
#ifndef __riscv64_ilp32__
#undef __riscv64_ilp32__
#endif
#ifndef __riscv64_ilp32f__
#undef __riscv64_ilp32f__
#endif
#ifndef __riscv64_ilp32d__
#undef __riscv64_ilp32d__
#endif
#ifndef __riscv64_lp64__
#undef __riscv64_lp64__
#endif
#ifndef __riscv64_lp64f__
#undef __riscv64_lp64f__
#endif
#ifndef __riscv64_lp64d__
#undef __riscv64_lp64d__
#endif
#ifndef __s390__
#undef __s390__
#endif
#ifndef __s390x__
#undef __s390x__
#endif
#ifndef __sh__
#undef __sh__
#endif
#ifndef __sparc__
#undef __sparc__
#endif
#ifndef __sparc64__
#undef __sparc64__
#endif
])

])


dnl Sets the HOST_CPU_C_ABI_32BIT variable to 'yes' if the C language ABI
dnl (application binary interface) is a 32-bit one, to 'no' if it is a 64-bit
dnl one, or to 'unknown' if unknown.
dnl This is a simplified variant of gl_HOST_CPU_C_ABI.
AC_DEFUN([gl_HOST_CPU_C_ABI_32BIT],
[
  AC_REQUIRE([AC_CANONICAL_HOST])
  AC_CACHE_CHECK([32-bit host C ABI], [gl_cv_host_cpu_c_abi_32bit],
    [if test -n "$gl_cv_host_cpu_c_abi"; then
       case "$gl_cv_host_cpu_c_abi" in
         i386 | x86_64-x32 | arm | armhf | arm64-ilp32 | hppa | ia64-ilp32 | mips | mipsn32 | powerpc | riscv*-ilp32* | s390 | sparc)
           gl_cv_host_cpu_c_abi_32bit=yes ;;
         x86_64 | alpha | arm64 | hppa64 | ia64 | mips64 | powerpc64 | powerpc64-elfv2 | riscv*-lp64* | s390x | sparc64 )
           gl_cv_host_cpu_c_abi_32bit=no ;;
         *)
           gl_cv_host_cpu_c_abi_32bit=unknown ;;
       esac
     else
       case "$host_cpu" in

         # CPUs that only support a 32-bit ABI.
         arc \
         | bfin \
         | cris* \
         | csky \
         | epiphany \
         | ft32 \
         | h8300 \
         | m68k \
         | microblaze | microblazeel \
         | nds32 | nds32le | nds32be \
         | nios2 | nios2eb | nios2el \
         | or1k* \
         | or32 \
         | sh | sh[1234] | sh[1234]e[lb] \
         | tic6x \
         | xtensa* )
           gl_cv_host_cpu_c_abi_32bit=yes
           ;;

         # CPUs that only support a 64-bit ABI.
changequote(,)dnl
         alpha | alphaev[4-8] | alphaev56 | alphapca5[67] | alphaev6[78] \
         | mmix )
changequote([,])dnl
           gl_cv_host_cpu_c_abi_32bit=no
           ;;

changequote(,)dnl
         i[34567]86 )
changequote([,])dnl
           gl_cv_host_cpu_c_abi_32bit=yes
           ;;

         x86_64 )
           # On x86_64 systems, the C compiler may be generating code in one of
           # these ABIs:
           # - 64-bit instruction set, 64-bit pointers, 64-bit 'long': x86_64.
           # - 64-bit instruction set, 64-bit pointers, 32-bit 'long': x86_64
           #   with native Windows (mingw, MSVC).
           # - 64-bit instruction set, 32-bit pointers, 32-bit 'long': x86_64-x32.
           # - 32-bit instruction set, 32-bit pointers, 32-bit 'long': i386.
           AC_COMPILE_IFELSE(
             [AC_LANG_SOURCE(
                [[#if (defined __x86_64__ || defined __amd64__ \
                       || defined _M_X64 || defined _M_AMD64) \
                      && !(defined __ILP32__ || defined _ILP32)
                   int ok;
                  #else
                   error fail
                  #endif
                ]])],
             [gl_cv_host_cpu_c_abi_32bit=no],
             [gl_cv_host_cpu_c_abi_32bit=yes])
           ;;

         arm* | aarch64 )
           # Assume arm with EABI.
           # On arm64 systems, the C compiler may be generating code in one of
           # these ABIs:
           # - aarch64 instruction set, 64-bit pointers, 64-bit 'long': arm64.
           # - aarch64 instruction set, 32-bit pointers, 32-bit 'long': arm64-ilp32.
           # - 32-bit instruction set, 32-bit pointers, 32-bit 'long': arm or armhf.
           AC_COMPILE_IFELSE(
             [AC_LANG_SOURCE(
                [[#if defined __aarch64__ && !(defined __ILP32__ || defined _ILP32)
                   int ok;
                  #else
                   error fail
                  #endif
                ]])],
             [gl_cv_host_cpu_c_abi_32bit=no],
             [gl_cv_host_cpu_c_abi_32bit=yes])
           ;;

         hppa1.0 | hppa1.1 | hppa2.0* | hppa64 )
           # On hppa, the C compiler may be generating 32-bit code or 64-bit
           # code. In the latter case, it defines _LP64 and __LP64__.
           AC_COMPILE_IFELSE(
             [AC_LANG_SOURCE(
                [[#ifdef __LP64__
                   int ok;
                  #else
                   error fail
                  #endif
                ]])],
             [gl_cv_host_cpu_c_abi_32bit=no],
             [gl_cv_host_cpu_c_abi_32bit=yes])
           ;;

         ia64* )
           # On ia64 on HP-UX, the C compiler may be generating 64-bit code or
           # 32-bit code. In the latter case, it defines _ILP32.
           AC_COMPILE_IFELSE(
             [AC_LANG_SOURCE(
                [[#ifdef _ILP32
                   int ok;
                  #else
                   error fail
                  #endif
                ]])],
             [gl_cv_host_cpu_c_abi_32bit=yes],
             [gl_cv_host_cpu_c_abi_32bit=no])
           ;;

         mips* )
           # We should also check for (_MIPS_SZPTR == 64), but gcc keeps this
           # at 32.
           AC_COMPILE_IFELSE(
             [AC_LANG_SOURCE(
                [[#if defined _MIPS_SZLONG && (_MIPS_SZLONG == 64)
                   int ok;
                  #else
                   error fail
                  #endif
                ]])],
             [gl_cv_host_cpu_c_abi_32bit=no],
             [gl_cv_host_cpu_c_abi_32bit=yes])
           ;;

         powerpc* )
           # Different ABIs are in use on AIX vs. Mac OS X vs. Linux,*BSD.
           # No need to distinguish them here; the caller may distinguish
           # them based on the OS.
           # On powerpc64 systems, the C compiler may still be generating
           # 32-bit code. And on powerpc-ibm-aix systems, the C compiler may
           # be generating 64-bit code.
           AC_COMPILE_IFELSE(
             [AC_LANG_SOURCE(
                [[#if defined __powerpc64__ || defined _ARCH_PPC64
                   int ok;
                  #else
                   error fail
                  #endif
                ]])],
             [gl_cv_host_cpu_c_abi_32bit=no],
             [gl_cv_host_cpu_c_abi_32bit=yes])
           ;;

         rs6000 )
           gl_cv_host_cpu_c_abi_32bit=yes
           ;;

         riscv32 | riscv64 )
           # There are 6 ABIs: ilp32, ilp32f, ilp32d, lp64, lp64f, lp64d.
           # Size of 'long' and 'void *':
           AC_COMPILE_IFELSE(
             [AC_LANG_SOURCE(
                [[#if defined __LP64__
                    int ok;
                  #else
                    error fail
                  #endif
                ]])],
             [gl_cv_host_cpu_c_abi_32bit=no],
             [gl_cv_host_cpu_c_abi_32bit=yes])
           ;;

         s390* )
           # On s390x, the C compiler may be generating 64-bit (= s390x) code
           # or 31-bit (= s390) code.
           AC_COMPILE_IFELSE(
             [AC_LANG_SOURCE(
                [[#if defined __LP64__ || defined __s390x__
                    int ok;
                  #else
                    error fail
                  #endif
                ]])],
             [gl_cv_host_cpu_c_abi_32bit=no],
             [gl_cv_host_cpu_c_abi_32bit=yes])
           ;;

         sparc | sparc64 )
           # UltraSPARCs running Linux have `uname -m` = "sparc64", but the
           # C compiler still generates 32-bit code.
           AC_COMPILE_IFELSE(
             [AC_LANG_SOURCE(
                [[#if defined __sparcv9 || defined __arch64__
                   int ok;
                  #else
                   error fail
                  #endif
                ]])],
             [gl_cv_host_cpu_c_abi_32bit=no],
             [gl_cv_host_cpu_c_abi_32bit=yes])
           ;;

         *)
           gl_cv_host_cpu_c_abi_32bit=unknown
           ;;
       esac
     fi
    ])

  HOST_CPU_C_ABI_32BIT="$gl_cv_host_cpu_c_abi_32bit"
])

# iconv.m4 serial 21
dnl Copyright (C) 2000-2002, 2007-2014, 2016-2020 Free Software Foundation,
dnl 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 From Bruno Haible.

AC_DEFUN([AM_ICONV_LINKFLAGS_BODY],
[
  dnl Prerequisites of AC_LIB_LINKFLAGS_BODY.
  AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
  AC_REQUIRE([AC_LIB_RPATH])

  dnl Search for libiconv and define LIBICONV, LTLIBICONV and INCICONV
  dnl accordingly.
  AC_LIB_LINKFLAGS_BODY([iconv])
])

AC_DEFUN([AM_ICONV_LINK],
[
  dnl Some systems have iconv in libc, some have it in libiconv (OSF/1 and
  dnl those with the standalone portable GNU libiconv installed).
  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles

  dnl Search for libiconv and define LIBICONV, LTLIBICONV and INCICONV
  dnl accordingly.
  AC_REQUIRE([AM_ICONV_LINKFLAGS_BODY])

  dnl Add $INCICONV to CPPFLAGS before performing the following checks,
  dnl because if the user has installed libiconv and not disabled its use
  dnl via --without-libiconv-prefix, he wants to use it. The first
  dnl AC_LINK_IFELSE will then fail, the second AC_LINK_IFELSE will succeed.
  am_save_CPPFLAGS="$CPPFLAGS"
  AC_LIB_APPENDTOVAR([CPPFLAGS], [$INCICONV])

  AC_CACHE_CHECK([for iconv], [am_cv_func_iconv], [
    am_cv_func_iconv="no, consider installing GNU libiconv"
    am_cv_lib_iconv=no
    AC_LINK_IFELSE(
      [AC_LANG_PROGRAM(
         [[
#include <stdlib.h>
#include <iconv.h>
         ]],
         [[iconv_t cd = iconv_open("","");
           iconv(cd,NULL,NULL,NULL,NULL);
           iconv_close(cd);]])],
      [am_cv_func_iconv=yes])
    if test "$am_cv_func_iconv" != yes; then
      am_save_LIBS="$LIBS"
      LIBS="$LIBS $LIBICONV"
      AC_LINK_IFELSE(
        [AC_LANG_PROGRAM(
           [[
#include <stdlib.h>
#include <iconv.h>
           ]],
           [[iconv_t cd = iconv_open("","");
             iconv(cd,NULL,NULL,NULL,NULL);
             iconv_close(cd);]])],
        [am_cv_lib_iconv=yes]
        [am_cv_func_iconv=yes])
      LIBS="$am_save_LIBS"
    fi
  ])
  if test "$am_cv_func_iconv" = yes; then
    AC_CACHE_CHECK([for working iconv], [am_cv_func_iconv_works], [
      dnl This tests against bugs in AIX 5.1, AIX 6.1..7.1, HP-UX 11.11,
      dnl Solaris 10.
      am_save_LIBS="$LIBS"
      if test $am_cv_lib_iconv = yes; then
        LIBS="$LIBS $LIBICONV"
      fi
      am_cv_func_iconv_works=no
      for ac_iconv_const in '' 'const'; do
        AC_RUN_IFELSE(
          [AC_LANG_PROGRAM(
             [[
#include <iconv.h>
#include <string.h>

#ifndef ICONV_CONST
# define ICONV_CONST $ac_iconv_const
#endif
             ]],
             [[int result = 0;
  /* Test against AIX 5.1 bug: Failures are not distinguishable from successful
     returns.  */
  {
    iconv_t cd_utf8_to_88591 = iconv_open ("ISO8859-1", "UTF-8");
    if (cd_utf8_to_88591 != (iconv_t)(-1))
      {
        static ICONV_CONST char input[] = "\342\202\254"; /* EURO SIGN */
        char buf[10];
        ICONV_CONST char *inptr = input;
        size_t inbytesleft = strlen (input);
        char *outptr = buf;
        size_t outbytesleft = sizeof (buf);
        size_t res = iconv (cd_utf8_to_88591,
                            &inptr, &inbytesleft,
                            &outptr, &outbytesleft);
        if (res == 0)
          result |= 1;
        iconv_close (cd_utf8_to_88591);
      }
  }
  /* Test against Solaris 10 bug: Failures are not distinguishable from
     successful returns.  */
  {
    iconv_t cd_ascii_to_88591 = iconv_open ("ISO8859-1", "646");
    if (cd_ascii_to_88591 != (iconv_t)(-1))
      {
        static ICONV_CONST char input[] = "\263";
        char buf[10];
        ICONV_CONST char *inptr = input;
        size_t inbytesleft = strlen (input);
        char *outptr = buf;
        size_t outbytesleft = sizeof (buf);
        size_t res = iconv (cd_ascii_to_88591,
                            &inptr, &inbytesleft,
                            &outptr, &outbytesleft);
        if (res == 0)
          result |= 2;
        iconv_close (cd_ascii_to_88591);
      }
  }
  /* Test against AIX 6.1..7.1 bug: Buffer overrun.  */
  {
    iconv_t cd_88591_to_utf8 = iconv_open ("UTF-8", "ISO-8859-1");
    if (cd_88591_to_utf8 != (iconv_t)(-1))
      {
        static ICONV_CONST char input[] = "\304";
        static char buf[2] = { (char)0xDE, (char)0xAD };
        ICONV_CONST char *inptr = input;
        size_t inbytesleft = 1;
        char *outptr = buf;
        size_t outbytesleft = 1;
        size_t res = iconv (cd_88591_to_utf8,
                            &inptr, &inbytesleft,
                            &outptr, &outbytesleft);
        if (res != (size_t)(-1) || outptr - buf > 1 || buf[1] != (char)0xAD)
          result |= 4;
        iconv_close (cd_88591_to_utf8);
      }
  }
#if 0 /* This bug could be worked around by the caller.  */
  /* Test against HP-UX 11.11 bug: Positive return value instead of 0.  */
  {
    iconv_t cd_88591_to_utf8 = iconv_open ("utf8", "iso88591");
    if (cd_88591_to_utf8 != (iconv_t)(-1))
      {
        static ICONV_CONST char input[] = "\304rger mit b\366sen B\374bchen ohne Augenma\337";
        char buf[50];
        ICONV_CONST char *inptr = input;
        size_t inbytesleft = strlen (input);
        char *outptr = buf;
        size_t outbytesleft = sizeof (buf);
        size_t res = iconv (cd_88591_to_utf8,
                            &inptr, &inbytesleft,
                            &outptr, &outbytesleft);
        if ((int)res > 0)
          result |= 8;
        iconv_close (cd_88591_to_utf8);
      }
  }
#endif
  /* Test against HP-UX 11.11 bug: No converter from EUC-JP to UTF-8 is
     provided.  */
  {
    /* Try standardized names.  */
    iconv_t cd1 = iconv_open ("UTF-8", "EUC-JP");
    /* Try IRIX, OSF/1 names.  */
    iconv_t cd2 = iconv_open ("UTF-8", "eucJP");
    /* Try AIX names.  */
    iconv_t cd3 = iconv_open ("UTF-8", "IBM-eucJP");
    /* Try HP-UX names.  */
    iconv_t cd4 = iconv_open ("utf8", "eucJP");
    if (cd1 == (iconv_t)(-1) && cd2 == (iconv_t)(-1)
        && cd3 == (iconv_t)(-1) && cd4 == (iconv_t)(-1))
      result |= 16;
    if (cd1 != (iconv_t)(-1))
      iconv_close (cd1);
    if (cd2 != (iconv_t)(-1))
      iconv_close (cd2);
    if (cd3 != (iconv_t)(-1))
      iconv_close (cd3);
    if (cd4 != (iconv_t)(-1))
      iconv_close (cd4);
  }
  return result;
]])],
          [am_cv_func_iconv_works=yes], ,
          [case "$host_os" in
             aix* | hpux*) am_cv_func_iconv_works="guessing no" ;;
             *)            am_cv_func_iconv_works="guessing yes" ;;
           esac])
        test "$am_cv_func_iconv_works" = no || break
      done
      LIBS="$am_save_LIBS"
    ])
    case "$am_cv_func_iconv_works" in
      *no) am_func_iconv=no am_cv_lib_iconv=no ;;
      *)   am_func_iconv=yes ;;
    esac
  else
    am_func_iconv=no am_cv_lib_iconv=no
  fi
  if test "$am_func_iconv" = yes; then
    AC_DEFINE([HAVE_ICONV], [1],
      [Define if you have the iconv() function and it works.])
  fi
  if test "$am_cv_lib_iconv" = yes; then
    AC_MSG_CHECKING([how to link with libiconv])
    AC_MSG_RESULT([$LIBICONV])
  else
    dnl If $LIBICONV didn't lead to a usable library, we don't need $INCICONV
    dnl either.
    CPPFLAGS="$am_save_CPPFLAGS"
    LIBICONV=
    LTLIBICONV=
  fi
  AC_SUBST([LIBICONV])
  AC_SUBST([LTLIBICONV])
])

dnl Define AM_ICONV using AC_DEFUN_ONCE for Autoconf >= 2.64, in order to
dnl avoid warnings like
dnl "warning: AC_REQUIRE: `AM_ICONV' was expanded before it was required".
dnl This is tricky because of the way 'aclocal' is implemented:
dnl - It requires defining an auxiliary macro whose name ends in AC_DEFUN.
dnl   Otherwise aclocal's initial scan pass would miss the macro definition.
dnl - It requires a line break inside the AC_DEFUN_ONCE and AC_DEFUN expansions.
dnl   Otherwise aclocal would emit many "Use of uninitialized value $1"
dnl   warnings.
m4_define([gl_iconv_AC_DEFUN],
  m4_version_prereq([2.64],
    [[AC_DEFUN_ONCE(
        [$1], [$2])]],
    [m4_ifdef([gl_00GNULIB],
       [[AC_DEFUN_ONCE(
           [$1], [$2])]],
       [[AC_DEFUN(
           [$1], [$2])]])]))
gl_iconv_AC_DEFUN([AM_ICONV],
[
  AM_ICONV_LINK
  if test "$am_cv_func_iconv" = yes; then
    AC_MSG_CHECKING([for iconv declaration])
    AC_CACHE_VAL([am_cv_proto_iconv], [
      AC_COMPILE_IFELSE(
        [AC_LANG_PROGRAM(
           [[
#include <stdlib.h>
#include <iconv.h>
extern
#ifdef __cplusplus
"C"
#endif
#if defined(__STDC__) || defined(_MSC_VER) || defined(__cplusplus)
size_t iconv (iconv_t cd, char * *inbuf, size_t *inbytesleft, char * *outbuf, size_t *outbytesleft);
#else
size_t iconv();
#endif
           ]],
           [[]])],
        [am_cv_proto_iconv_arg1=""],
        [am_cv_proto_iconv_arg1="const"])
      am_cv_proto_iconv="extern size_t iconv (iconv_t cd, $am_cv_proto_iconv_arg1 char * *inbuf, size_t *inbytesleft, char * *outbuf, size_t *outbytesleft);"])
    am_cv_proto_iconv=`echo "[$]am_cv_proto_iconv" | tr -s ' ' | sed -e 's/( /(/'`
    AC_MSG_RESULT([
         $am_cv_proto_iconv])
  else
    dnl When compiling GNU libiconv on a system that does not have iconv yet,
    dnl pick the POSIX compliant declaration without 'const'.
    am_cv_proto_iconv_arg1=""
  fi
  AC_DEFINE_UNQUOTED([ICONV_CONST], [$am_cv_proto_iconv_arg1],
    [Define as const if the declaration of iconv() needs const.])
  dnl Also substitute ICONV_CONST in the gnulib generated <iconv.h>.
  m4_ifdef([gl_ICONV_H_DEFAULTS],
    [AC_REQUIRE([gl_ICONV_H_DEFAULTS])
     if test -n "$am_cv_proto_iconv_arg1"; then
       ICONV_CONST="const"
     fi
    ])
])

# lib-ld.m4 serial 9
dnl Copyright (C) 1996-2003, 2009-2020 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 Subroutines of libtool.m4,
dnl with replacements s/_*LT_PATH/AC_LIB_PROG/ and s/lt_/acl_/ to avoid
dnl collision with libtool.m4.

dnl From libtool-2.4. Sets the variable with_gnu_ld to yes or no.
AC_DEFUN([AC_LIB_PROG_LD_GNU],
[AC_CACHE_CHECK([if the linker ($LD) is GNU ld], [acl_cv_prog_gnu_ld],
[# I'd rather use --version here, but apparently some GNU lds only accept -v.
case `$LD -v 2>&1 </dev/null` in
*GNU* | *'with BFD'*)
  acl_cv_prog_gnu_ld=yes
  ;;
*)
  acl_cv_prog_gnu_ld=no
  ;;
esac])
with_gnu_ld=$acl_cv_prog_gnu_ld
])

dnl From libtool-2.4. Sets the variable LD.
AC_DEFUN([AC_LIB_PROG_LD],
[AC_REQUIRE([AC_PROG_CC])dnl
AC_REQUIRE([AC_CANONICAL_HOST])dnl

AC_ARG_WITH([gnu-ld],
    [AS_HELP_STRING([--with-gnu-ld],
        [assume the C compiler uses GNU ld [default=no]])],
    [test "$withval" = no || with_gnu_ld=yes],
    [with_gnu_ld=no])dnl

# Prepare PATH_SEPARATOR.
# The user is always right.
if test "${PATH_SEPARATOR+set}" != set; then
  # Determine PATH_SEPARATOR by trying to find /bin/sh in a PATH which
  # contains only /bin. Note that ksh looks also at the FPATH variable,
  # so we have to set that as well for the test.
  PATH_SEPARATOR=:
  (PATH='/bin;/bin'; FPATH=$PATH; sh -c :) >/dev/null 2>&1 \
    && { (PATH='/bin:/bin'; FPATH=$PATH; sh -c :) >/dev/null 2>&1 \
           || PATH_SEPARATOR=';'
       }
fi

if test -n "$LD"; then
  AC_MSG_CHECKING([for ld])
elif test "$GCC" = yes; then
  AC_MSG_CHECKING([for ld used by $CC])
elif test "$with_gnu_ld" = yes; then
  AC_MSG_CHECKING([for GNU ld])
else
  AC_MSG_CHECKING([for non-GNU ld])
fi
if test -n "$LD"; then
  # Let the user override the test with a path.
  :
else
  AC_CACHE_VAL([acl_cv_path_LD],
  [
    acl_cv_path_LD= # Final result of this test
    ac_prog=ld # Program to search in $PATH
    if test "$GCC" = yes; then
      # Check if gcc -print-prog-name=ld gives a path.
      case $host in
        *-*-mingw*)
          # gcc leaves a trailing carriage return which upsets mingw
          acl_output=`($CC -print-prog-name=ld) 2>&5 | tr -d '\015'` ;;
        *)
          acl_output=`($CC -print-prog-name=ld) 2>&5` ;;
      esac
      case $acl_output in
        # Accept absolute paths.
        [[\\/]]* | ?:[[\\/]]*)
          re_direlt='/[[^/]][[^/]]*/\.\./'
          # Canonicalize the pathname of ld
          acl_output=`echo "$acl_output" | sed 's%\\\\%/%g'`
          while echo "$acl_output" | grep "$re_direlt" > /dev/null 2>&1; do
            acl_output=`echo $acl_output | sed "s%$re_direlt%/%"`
          done
          # Got the pathname. No search in PATH is needed.
          acl_cv_path_LD="$acl_output"
          ac_prog=
          ;;
        "")
          # If it fails, then pretend we aren't using GCC.
          ;;
        *)
          # If it is relative, then search for the first ld in PATH.
          with_gnu_ld=unknown
          ;;
      esac
    fi
    if test -n "$ac_prog"; then
      # Search for $ac_prog in $PATH.
      acl_save_ifs="$IFS"; IFS=$PATH_SEPARATOR
      for ac_dir in $PATH; do
        IFS="$acl_save_ifs"
        test -z "$ac_dir" && ac_dir=.
        if test -f "$ac_dir/$ac_prog" || test -f "$ac_dir/$ac_prog$ac_exeext"; then
          acl_cv_path_LD="$ac_dir/$ac_prog"
          # Check to see if the program is GNU ld.  I'd rather use --version,
          # but apparently some variants of GNU ld only accept -v.
          # Break only if it was the GNU/non-GNU ld that we prefer.
          case `"$acl_cv_path_LD" -v 2>&1 </dev/null` in
            *GNU* | *'with BFD'*)
              test "$with_gnu_ld" != no && break
              ;;
            *)
              test "$with_gnu_ld" != yes && break
              ;;
          esac
        fi
      done
      IFS="$acl_save_ifs"
    fi
    case $host in
      *-*-aix*)
        AC_COMPILE_IFELSE(
          [AC_LANG_SOURCE(
             [[#if defined __powerpc64__ || defined _ARCH_PPC64
                int ok;
               #else
                error fail
               #endif
             ]])],
          [# The compiler produces 64-bit code. Add option '-b64' so that the
           # linker groks 64-bit object files.
           case "$acl_cv_path_LD " in
             *" -b64 "*) ;;
             *) acl_cv_path_LD="$acl_cv_path_LD -b64" ;;
           esac
          ], [])
        ;;
      sparc64-*-netbsd*)
        AC_COMPILE_IFELSE(
          [AC_LANG_SOURCE(
             [[#if defined __sparcv9 || defined __arch64__
                int ok;
               #else
                error fail
               #endif
             ]])],
          [],
          [# The compiler produces 32-bit code. Add option '-m elf32_sparc'
           # so that the linker groks 32-bit object files.
           case "$acl_cv_path_LD " in
             *" -m elf32_sparc "*) ;;
             *) acl_cv_path_LD="$acl_cv_path_LD -m elf32_sparc" ;;
           esac
          ])
        ;;
    esac
  ])
  LD="$acl_cv_path_LD"
fi
if test -n "$LD"; then
  AC_MSG_RESULT([$LD])
else
  AC_MSG_RESULT([no])
  AC_MSG_ERROR([no acceptable ld found in \$PATH])
fi
AC_LIB_PROG_LD_GNU
])

# lib-link.m4 serial 31
dnl Copyright (C) 2001-2020 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 From Bruno Haible.

AC_PREREQ([2.61])

dnl AC_LIB_LINKFLAGS(name [, dependencies]) searches for libname and
dnl the libraries corresponding to explicit and implicit dependencies.
dnl Sets and AC_SUBSTs the LIB${NAME} and LTLIB${NAME} variables and
dnl augments the CPPFLAGS variable.
dnl Sets and AC_SUBSTs the LIB${NAME}_PREFIX variable to nonempty if libname
dnl was found in ${LIB${NAME}_PREFIX}/$acl_libdirstem.
AC_DEFUN([AC_LIB_LINKFLAGS],
[
  AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
  AC_REQUIRE([AC_LIB_RPATH])
  pushdef([Name],[m4_translit([$1],[./+-], [____])])
  pushdef([NAME],[m4_translit([$1],[abcdefghijklmnopqrstuvwxyz./+-],
                                   [ABCDEFGHIJKLMNOPQRSTUVWXYZ____])])
  AC_CACHE_CHECK([how to link with lib[]$1], [ac_cv_lib[]Name[]_libs], [
    AC_LIB_LINKFLAGS_BODY([$1], [$2])
    ac_cv_lib[]Name[]_libs="$LIB[]NAME"
    ac_cv_lib[]Name[]_ltlibs="$LTLIB[]NAME"
    ac_cv_lib[]Name[]_cppflags="$INC[]NAME"
    ac_cv_lib[]Name[]_prefix="$LIB[]NAME[]_PREFIX"
  ])
  LIB[]NAME="$ac_cv_lib[]Name[]_libs"
  LTLIB[]NAME="$ac_cv_lib[]Name[]_ltlibs"
  INC[]NAME="$ac_cv_lib[]Name[]_cppflags"
  LIB[]NAME[]_PREFIX="$ac_cv_lib[]Name[]_prefix"
  AC_LIB_APPENDTOVAR([CPPFLAGS], [$INC]NAME)
  AC_SUBST([LIB]NAME)
  AC_SUBST([LTLIB]NAME)
  AC_SUBST([LIB]NAME[_PREFIX])
  dnl Also set HAVE_LIB[]NAME so that AC_LIB_HAVE_LINKFLAGS can reuse the
  dnl results of this search when this library appears as a dependency.
  HAVE_LIB[]NAME=yes
  popdef([NAME])
  popdef([Name])
])

dnl AC_LIB_HAVE_LINKFLAGS(name, dependencies, includes, testcode, [missing-message])
dnl searches for libname and the libraries corresponding to explicit and
dnl implicit dependencies, together with the specified include files and
dnl the ability to compile and link the specified testcode. The missing-message
dnl defaults to 'no' and may contain additional hints for the user.
dnl If found, it sets and AC_SUBSTs HAVE_LIB${NAME}=yes and the LIB${NAME}
dnl and LTLIB${NAME} variables and augments the CPPFLAGS variable, and
dnl #defines HAVE_LIB${NAME} to 1. Otherwise, it sets and AC_SUBSTs
dnl HAVE_LIB${NAME}=no and LIB${NAME} and LTLIB${NAME} to empty.
dnl Sets and AC_SUBSTs the LIB${NAME}_PREFIX variable to nonempty if libname
dnl was found in ${LIB${NAME}_PREFIX}/$acl_libdirstem.
AC_DEFUN([AC_LIB_HAVE_LINKFLAGS],
[
  AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
  AC_REQUIRE([AC_LIB_RPATH])
  pushdef([Name],[m4_translit([$1],[./+-], [____])])
  pushdef([NAME],[m4_translit([$1],[abcdefghijklmnopqrstuvwxyz./+-],
                                   [ABCDEFGHIJKLMNOPQRSTUVWXYZ____])])

  dnl Search for lib[]Name and define LIB[]NAME, LTLIB[]NAME and INC[]NAME
  dnl accordingly.
  AC_LIB_LINKFLAGS_BODY([$1], [$2])

  dnl Add $INC[]NAME to CPPFLAGS before performing the following checks,
  dnl because if the user has installed lib[]Name and not disabled its use
  dnl via --without-lib[]Name-prefix, he wants to use it.
  ac_save_CPPFLAGS="$CPPFLAGS"
  AC_LIB_APPENDTOVAR([CPPFLAGS], [$INC]NAME)

  AC_CACHE_CHECK([for lib[]$1], [ac_cv_lib[]Name], [
    ac_save_LIBS="$LIBS"
    dnl If $LIB[]NAME contains some -l options, add it to the end of LIBS,
    dnl because these -l options might require -L options that are present in
    dnl LIBS. -l options benefit only from the -L options listed before it.
    dnl Otherwise, add it to the front of LIBS, because it may be a static
    dnl library that depends on another static library that is present in LIBS.
    dnl Static libraries benefit only from the static libraries listed after
    dnl it.
    case " $LIB[]NAME" in
      *" -l"*) LIBS="$LIBS $LIB[]NAME" ;;
      *)       LIBS="$LIB[]NAME $LIBS" ;;
    esac
    AC_LINK_IFELSE(
      [AC_LANG_PROGRAM([[$3]], [[$4]])],
      [ac_cv_lib[]Name=yes],
      [ac_cv_lib[]Name='m4_if([$5], [], [no], [[$5]])'])
    LIBS="$ac_save_LIBS"
  ])
  if test "$ac_cv_lib[]Name" = yes; then
    HAVE_LIB[]NAME=yes
    AC_DEFINE([HAVE_LIB]NAME, 1, [Define if you have the lib][$1 library.])
    AC_MSG_CHECKING([how to link with lib[]$1])
    AC_MSG_RESULT([$LIB[]NAME])
  else
    HAVE_LIB[]NAME=no
    dnl If $LIB[]NAME didn't lead to a usable library, we don't need
    dnl $INC[]NAME either.
    CPPFLAGS="$ac_save_CPPFLAGS"
    LIB[]NAME=
    LTLIB[]NAME=
    LIB[]NAME[]_PREFIX=
  fi
  AC_SUBST([HAVE_LIB]NAME)
  AC_SUBST([LIB]NAME)
  AC_SUBST([LTLIB]NAME)
  AC_SUBST([LIB]NAME[_PREFIX])
  popdef([NAME])
  popdef([Name])
])

dnl Determine the platform dependent parameters needed to use rpath:
dnl   acl_libext,
dnl   acl_shlibext,
dnl   acl_libname_spec,
dnl   acl_library_names_spec,
dnl   acl_hardcode_libdir_flag_spec,
dnl   acl_hardcode_libdir_separator,
dnl   acl_hardcode_direct,
dnl   acl_hardcode_minus_L.
AC_DEFUN([AC_LIB_RPATH],
[
  dnl Complain if config.rpath is missing.
  AC_REQUIRE_AUX_FILE([config.rpath])
  AC_REQUIRE([AC_PROG_CC])                dnl we use $CC, $GCC, $LDFLAGS
  AC_REQUIRE([AC_LIB_PROG_LD])            dnl we use $LD, $with_gnu_ld
  AC_REQUIRE([AC_CANONICAL_HOST])         dnl we use $host
  AC_REQUIRE([AC_CONFIG_AUX_DIR_DEFAULT]) dnl we use $ac_aux_dir
  AC_CACHE_CHECK([for shared library run path origin], [acl_cv_rpath], [
    CC="$CC" GCC="$GCC" LDFLAGS="$LDFLAGS" LD="$LD" with_gnu_ld="$with_gnu_ld" \
    ${CONFIG_SHELL-/bin/sh} "$ac_aux_dir/config.rpath" "$host" > conftest.sh
    . ./conftest.sh
    rm -f ./conftest.sh
    acl_cv_rpath=done
  ])
  wl="$acl_cv_wl"
  acl_libext="$acl_cv_libext"
  acl_shlibext="$acl_cv_shlibext"
  acl_libname_spec="$acl_cv_libname_spec"
  acl_library_names_spec="$acl_cv_library_names_spec"
  acl_hardcode_libdir_flag_spec="$acl_cv_hardcode_libdir_flag_spec"
  acl_hardcode_libdir_separator="$acl_cv_hardcode_libdir_separator"
  acl_hardcode_direct="$acl_cv_hardcode_direct"
  acl_hardcode_minus_L="$acl_cv_hardcode_minus_L"
  dnl Determine whether the user wants rpath handling at all.
  AC_ARG_ENABLE([rpath],
    [  --disable-rpath         do not hardcode runtime library paths],
    :, enable_rpath=yes)
])

dnl AC_LIB_FROMPACKAGE(name, package)
dnl declares that libname comes from the given package. The configure file
dnl will then not have a --with-libname-prefix option but a
dnl --with-package-prefix option. Several libraries can come from the same
dnl package. This declaration must occur before an AC_LIB_LINKFLAGS or similar
dnl macro call that searches for libname.
AC_DEFUN([AC_LIB_FROMPACKAGE],
[
  pushdef([NAME],[m4_translit([$1],[abcdefghijklmnopqrstuvwxyz./+-],
                                   [ABCDEFGHIJKLMNOPQRSTUVWXYZ____])])
  define([acl_frompackage_]NAME, [$2])
  popdef([NAME])
  pushdef([PACK],[$2])
  pushdef([PACKUP],[m4_translit(PACK,[abcdefghijklmnopqrstuvwxyz./+-],
                                     [ABCDEFGHIJKLMNOPQRSTUVWXYZ____])])
  define([acl_libsinpackage_]PACKUP,
    m4_ifdef([acl_libsinpackage_]PACKUP, [m4_defn([acl_libsinpackage_]PACKUP)[, ]],)[lib$1])
  popdef([PACKUP])
  popdef([PACK])
])

dnl AC_LIB_LINKFLAGS_BODY(name [, dependencies]) searches for libname and
dnl the libraries corresponding to explicit and implicit dependencies.
dnl Sets the LIB${NAME}, LTLIB${NAME} and INC${NAME} variables.
dnl Also, sets the LIB${NAME}_PREFIX variable to nonempty if libname was found
dnl in ${LIB${NAME}_PREFIX}/$acl_libdirstem.
AC_DEFUN([AC_LIB_LINKFLAGS_BODY],
[
  AC_REQUIRE([AC_LIB_PREPARE_MULTILIB])
  pushdef([NAME],[m4_translit([$1],[abcdefghijklmnopqrstuvwxyz./+-],
                                   [ABCDEFGHIJKLMNOPQRSTUVWXYZ____])])
  pushdef([PACK],[m4_ifdef([acl_frompackage_]NAME, [acl_frompackage_]NAME, lib[$1])])
  pushdef([PACKUP],[m4_translit(PACK,[abcdefghijklmnopqrstuvwxyz./+-],
                                     [ABCDEFGHIJKLMNOPQRSTUVWXYZ____])])
  pushdef([PACKLIBS],[m4_ifdef([acl_frompackage_]NAME, [acl_libsinpackage_]PACKUP, lib[$1])])
  dnl By default, look in $includedir and $libdir.
  use_additional=yes
  AC_LIB_WITH_FINAL_PREFIX([
    eval additional_includedir=\"$includedir\"
    eval additional_libdir=\"$libdir\"
    eval additional_libdir2=\"$exec_prefix/$acl_libdirstem2\"
    eval additional_libdir3=\"$exec_prefix/$acl_libdirstem3\"
  ])
  AC_ARG_WITH(PACK[-prefix],
[[  --with-]]PACK[[-prefix[=DIR]  search for ]PACKLIBS[ in DIR/include and DIR/lib
  --without-]]PACK[[-prefix     don't search for ]PACKLIBS[ in includedir and libdir]],
[
    if test "X$withval" = "Xno"; then
      use_additional=no
    else
      if test "X$withval" = "X"; then
        AC_LIB_WITH_FINAL_PREFIX([
          eval additional_includedir=\"$includedir\"
          eval additional_libdir=\"$libdir\"
          eval additional_libdir2=\"$exec_prefix/$acl_libdirstem2\"
          eval additional_libdir3=\"$exec_prefix/$acl_libdirstem3\"
        ])
      else
        additional_includedir="$withval/include"
        additional_libdir="$withval/$acl_libdirstem"
        additional_libdir2="$withval/$acl_libdirstem2"
        additional_libdir3="$withval/$acl_libdirstem3"
      fi
    fi
])
  if test "X$additional_libdir2" = "X$additional_libdir"; then
    additional_libdir2=
  fi
  if test "X$additional_libdir3" = "X$additional_libdir"; then
    additional_libdir3=
  fi
  dnl Search the library and its dependencies in $additional_libdir and
  dnl $LDFLAGS. Using breadth-first-seach.
  LIB[]NAME=
  LTLIB[]NAME=
  INC[]NAME=
  LIB[]NAME[]_PREFIX=
  dnl HAVE_LIB${NAME} is an indicator that LIB${NAME}, LTLIB${NAME} have been
  dnl computed. So it has to be reset here.
  HAVE_LIB[]NAME=
  rpathdirs=
  ltrpathdirs=
  names_already_handled=
  names_next_round='$1 $2'
  while test -n "$names_next_round"; do
    names_this_round="$names_next_round"
    names_next_round=
    for name in $names_this_round; do
      already_handled=
      for n in $names_already_handled; do
        if test "$n" = "$name"; then
          already_handled=yes
          break
        fi
      done
      if test -z "$already_handled"; then
        names_already_handled="$names_already_handled $name"
        dnl See if it was already located by an earlier AC_LIB_LINKFLAGS
        dnl or AC_LIB_HAVE_LINKFLAGS call.
        uppername=`echo "$name" | sed -e 'y|abcdefghijklmnopqrstuvwxyz./+-|ABCDEFGHIJKLMNOPQRSTUVWXYZ____|'`
        eval value=\"\$HAVE_LIB$uppername\"
        if test -n "$value"; then
          if test "$value" = yes; then
            eval value=\"\$LIB$uppername\"
            test -z "$value" || LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$value"
            eval value=\"\$LTLIB$uppername\"
            test -z "$value" || LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }$value"
          else
            dnl An earlier call to AC_LIB_HAVE_LINKFLAGS has determined
            dnl that this library doesn't exist. So just drop it.
            :
          fi
        else
          dnl Search the library lib$name in $additional_libdir and $LDFLAGS
          dnl and the already constructed $LIBNAME/$LTLIBNAME.
          found_dir=
          found_la=
          found_so=
          found_a=
          eval libname=\"$acl_libname_spec\"    # typically: libname=lib$name
          if test -n "$acl_shlibext"; then
            shrext=".$acl_shlibext"             # typically: shrext=.so
          else
            shrext=
          fi
          if test $use_additional = yes; then
            for additional_libdir_variable in additional_libdir additional_libdir2 additional_libdir3; do
              if test "X$found_dir" = "X"; then
                eval dir=\$$additional_libdir_variable
                if test -n "$dir"; then
                  dnl The same code as in the loop below:
                  dnl First look for a shared library.
                  if test -n "$acl_shlibext"; then
                    if test -f "$dir/$libname$shrext" && acl_is_expected_elfclass < "$dir/$libname$shrext"; then
                      found_dir="$dir"
                      found_so="$dir/$libname$shrext"
                    else
                      if test "$acl_library_names_spec" = '$libname$shrext$versuffix'; then
                        ver=`(cd "$dir" && \
                              for f in "$libname$shrext".*; do echo "$f"; done \
                              | sed -e "s,^$libname$shrext\\\\.,," \
                              | sort -t '.' -n -r -k1,1 -k2,2 -k3,3 -k4,4 -k5,5 \
                              | sed 1q ) 2>/dev/null`
                        if test -n "$ver" && test -f "$dir/$libname$shrext.$ver" && acl_is_expected_elfclass < "$dir/$libname$shrext.$ver"; then
                          found_dir="$dir"
                          found_so="$dir/$libname$shrext.$ver"
                        fi
                      else
                        eval library_names=\"$acl_library_names_spec\"
                        for f in $library_names; do
                          if test -f "$dir/$f" && acl_is_expected_elfclass < "$dir/$f"; then
                            found_dir="$dir"
                            found_so="$dir/$f"
                            break
                          fi
                        done
                      fi
                    fi
                  fi
                  dnl Then look for a static library.
                  if test "X$found_dir" = "X"; then
                    if test -f "$dir/$libname.$acl_libext" && ${AR-ar} -p "$dir/$libname.$acl_libext" | acl_is_expected_elfclass; then
                      found_dir="$dir"
                      found_a="$dir/$libname.$acl_libext"
                    fi
                  fi
                  if test "X$found_dir" != "X"; then
                    if test -f "$dir/$libname.la"; then
                      found_la="$dir/$libname.la"
                    fi
                  fi
                fi
              fi
            done
          fi
          if test "X$found_dir" = "X"; then
            for x in $LDFLAGS $LTLIB[]NAME; do
              AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
              case "$x" in
                -L*)
                  dir=`echo "X$x" | sed -e 's/^X-L//'`
                  dnl First look for a shared library.
                  if test -n "$acl_shlibext"; then
                    if test -f "$dir/$libname$shrext" && acl_is_expected_elfclass < "$dir/$libname$shrext"; then
                      found_dir="$dir"
                      found_so="$dir/$libname$shrext"
                    else
                      if test "$acl_library_names_spec" = '$libname$shrext$versuffix'; then
                        ver=`(cd "$dir" && \
                              for f in "$libname$shrext".*; do echo "$f"; done \
                              | sed -e "s,^$libname$shrext\\\\.,," \
                              | sort -t '.' -n -r -k1,1 -k2,2 -k3,3 -k4,4 -k5,5 \
                              | sed 1q ) 2>/dev/null`
                        if test -n "$ver" && test -f "$dir/$libname$shrext.$ver" && acl_is_expected_elfclass < "$dir/$libname$shrext.$ver"; then
                          found_dir="$dir"
                          found_so="$dir/$libname$shrext.$ver"
                        fi
                      else
                        eval library_names=\"$acl_library_names_spec\"
                        for f in $library_names; do
                          if test -f "$dir/$f" && acl_is_expected_elfclass < "$dir/$f"; then
                            found_dir="$dir"
                            found_so="$dir/$f"
                            break
                          fi
                        done
                      fi
                    fi
                  fi
                  dnl Then look for a static library.
                  if test "X$found_dir" = "X"; then
                    if test -f "$dir/$libname.$acl_libext" && ${AR-ar} -p "$dir/$libname.$acl_libext" | acl_is_expected_elfclass; then
                      found_dir="$dir"
                      found_a="$dir/$libname.$acl_libext"
                    fi
                  fi
                  if test "X$found_dir" != "X"; then
                    if test -f "$dir/$libname.la"; then
                      found_la="$dir/$libname.la"
                    fi
                  fi
                  ;;
              esac
              if test "X$found_dir" != "X"; then
                break
              fi
            done
          fi
          if test "X$found_dir" != "X"; then
            dnl Found the library.
            LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-L$found_dir -l$name"
            if test "X$found_so" != "X"; then
              dnl Linking with a shared library. We attempt to hardcode its
              dnl directory into the executable's runpath, unless it's the
              dnl standard /usr/lib.
              if test "$enable_rpath" = no \
                 || test "X$found_dir" = "X/usr/$acl_libdirstem" \
                 || test "X$found_dir" = "X/usr/$acl_libdirstem2" \
                 || test "X$found_dir" = "X/usr/$acl_libdirstem3"; then
                dnl No hardcoding is needed.
                LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
              else
                dnl Use an explicit option to hardcode DIR into the resulting
                dnl binary.
                dnl Potentially add DIR to ltrpathdirs.
                dnl The ltrpathdirs will be appended to $LTLIBNAME at the end.
                haveit=
                for x in $ltrpathdirs; do
                  if test "X$x" = "X$found_dir"; then
                    haveit=yes
                    break
                  fi
                done
                if test -z "$haveit"; then
                  ltrpathdirs="$ltrpathdirs $found_dir"
                fi
                dnl The hardcoding into $LIBNAME is system dependent.
                if test "$acl_hardcode_direct" = yes; then
                  dnl Using DIR/libNAME.so during linking hardcodes DIR into the
                  dnl resulting binary.
                  LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
                else
                  if test -n "$acl_hardcode_libdir_flag_spec" && test "$acl_hardcode_minus_L" = no; then
                    dnl Use an explicit option to hardcode DIR into the resulting
                    dnl binary.
                    LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
                    dnl Potentially add DIR to rpathdirs.
                    dnl The rpathdirs will be appended to $LIBNAME at the end.
                    haveit=
                    for x in $rpathdirs; do
                      if test "X$x" = "X$found_dir"; then
                        haveit=yes
                        break
                      fi
                    done
                    if test -z "$haveit"; then
                      rpathdirs="$rpathdirs $found_dir"
                    fi
                  else
                    dnl Rely on "-L$found_dir".
                    dnl But don't add it if it's already contained in the LDFLAGS
                    dnl or the already constructed $LIBNAME
                    haveit=
                    for x in $LDFLAGS $LIB[]NAME; do
                      AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
                      if test "X$x" = "X-L$found_dir"; then
                        haveit=yes
                        break
                      fi
                    done
                    if test -z "$haveit"; then
                      LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$found_dir"
                    fi
                    if test "$acl_hardcode_minus_L" != no; then
                      dnl FIXME: Not sure whether we should use
                      dnl "-L$found_dir -l$name" or "-L$found_dir $found_so"
                      dnl here.
                      LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
                    else
                      dnl We cannot use $acl_hardcode_runpath_var and LD_RUN_PATH
                      dnl here, because this doesn't fit in flags passed to the
                      dnl compiler. So give up. No hardcoding. This affects only
                      dnl very old systems.
                      dnl FIXME: Not sure whether we should use
                      dnl "-L$found_dir -l$name" or "-L$found_dir $found_so"
                      dnl here.
                      LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-l$name"
                    fi
                  fi
                fi
              fi
            else
              if test "X$found_a" != "X"; then
                dnl Linking with a static library.
                LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_a"
              else
                dnl We shouldn't come here, but anyway it's good to have a
                dnl fallback.
                LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$found_dir -l$name"
              fi
            fi
            dnl Assume the include files are nearby.
            additional_includedir=
            case "$found_dir" in
              */$acl_libdirstem | */$acl_libdirstem/)
                basedir=`echo "X$found_dir" | sed -e 's,^X,,' -e "s,/$acl_libdirstem/"'*$,,'`
                if test "$name" = '$1'; then
                  LIB[]NAME[]_PREFIX="$basedir"
                fi
                additional_includedir="$basedir/include"
                ;;
              */$acl_libdirstem2 | */$acl_libdirstem2/)
                basedir=`echo "X$found_dir" | sed -e 's,^X,,' -e "s,/$acl_libdirstem2/"'*$,,'`
                if test "$name" = '$1'; then
                  LIB[]NAME[]_PREFIX="$basedir"
                fi
                additional_includedir="$basedir/include"
                ;;
              */$acl_libdirstem3 | */$acl_libdirstem3/)
                basedir=`echo "X$found_dir" | sed -e 's,^X,,' -e "s,/$acl_libdirstem3/"'*$,,'`
                if test "$name" = '$1'; then
                  LIB[]NAME[]_PREFIX="$basedir"
                fi
                additional_includedir="$basedir/include"
                ;;
            esac
            if test "X$additional_includedir" != "X"; then
              dnl Potentially add $additional_includedir to $INCNAME.
              dnl But don't add it
              dnl   1. if it's the standard /usr/include,
              dnl   2. if it's /usr/local/include and we are using GCC on Linux,
              dnl   3. if it's already present in $CPPFLAGS or the already
              dnl      constructed $INCNAME,
              dnl   4. if it doesn't exist as a directory.
              if test "X$additional_includedir" != "X/usr/include"; then
                haveit=
                if test "X$additional_includedir" = "X/usr/local/include"; then
                  if test -n "$GCC"; then
                    case $host_os in
                      linux* | gnu* | k*bsd*-gnu) haveit=yes;;
                    esac
                  fi
                fi
                if test -z "$haveit"; then
                  for x in $CPPFLAGS $INC[]NAME; do
                    AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
                    if test "X$x" = "X-I$additional_includedir"; then
                      haveit=yes
                      break
                    fi
                  done
                  if test -z "$haveit"; then
                    if test -d "$additional_includedir"; then
                      dnl Really add $additional_includedir to $INCNAME.
                      INC[]NAME="${INC[]NAME}${INC[]NAME:+ }-I$additional_includedir"
                    fi
                  fi
                fi
              fi
            fi
            dnl Look for dependencies.
            if test -n "$found_la"; then
              dnl Read the .la file. It defines the variables
              dnl dlname, library_names, old_library, dependency_libs, current,
              dnl age, revision, installed, dlopen, dlpreopen, libdir.
              save_libdir="$libdir"
              case "$found_la" in
                */* | *\\*) . "$found_la" ;;
                *) . "./$found_la" ;;
              esac
              libdir="$save_libdir"
              dnl We use only dependency_libs.
              for dep in $dependency_libs; do
                case "$dep" in
                  -L*)
                    dependency_libdir=`echo "X$dep" | sed -e 's/^X-L//'`
                    dnl Potentially add $dependency_libdir to $LIBNAME and $LTLIBNAME.
                    dnl But don't add it
                    dnl   1. if it's the standard /usr/lib,
                    dnl   2. if it's /usr/local/lib and we are using GCC on Linux,
                    dnl   3. if it's already present in $LDFLAGS or the already
                    dnl      constructed $LIBNAME,
                    dnl   4. if it doesn't exist as a directory.
                    if test "X$dependency_libdir" != "X/usr/$acl_libdirstem" \
                       && test "X$dependency_libdir" != "X/usr/$acl_libdirstem2" \
                       && test "X$dependency_libdir" != "X/usr/$acl_libdirstem3"; then
                      haveit=
                      if test "X$dependency_libdir" = "X/usr/local/$acl_libdirstem" \
                         || test "X$dependency_libdir" = "X/usr/local/$acl_libdirstem2" \
                         || test "X$dependency_libdir" = "X/usr/local/$acl_libdirstem3"; then
                        if test -n "$GCC"; then
                          case $host_os in
                            linux* | gnu* | k*bsd*-gnu) haveit=yes;;
                          esac
                        fi
                      fi
                      if test -z "$haveit"; then
                        haveit=
                        for x in $LDFLAGS $LIB[]NAME; do
                          AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
                          if test "X$x" = "X-L$dependency_libdir"; then
                            haveit=yes
                            break
                          fi
                        done
                        if test -z "$haveit"; then
                          if test -d "$dependency_libdir"; then
                            dnl Really add $dependency_libdir to $LIBNAME.
                            LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$dependency_libdir"
                          fi
                        fi
                        haveit=
                        for x in $LDFLAGS $LTLIB[]NAME; do
                          AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
                          if test "X$x" = "X-L$dependency_libdir"; then
                            haveit=yes
                            break
                          fi
                        done
                        if test -z "$haveit"; then
                          if test -d "$dependency_libdir"; then
                            dnl Really add $dependency_libdir to $LTLIBNAME.
                            LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-L$dependency_libdir"
                          fi
                        fi
                      fi
                    fi
                    ;;
                  -R*)
                    dir=`echo "X$dep" | sed -e 's/^X-R//'`
                    if test "$enable_rpath" != no; then
                      dnl Potentially add DIR to rpathdirs.
                      dnl The rpathdirs will be appended to $LIBNAME at the end.
                      haveit=
                      for x in $rpathdirs; do
                        if test "X$x" = "X$dir"; then
                          haveit=yes
                          break
                        fi
                      done
                      if test -z "$haveit"; then
                        rpathdirs="$rpathdirs $dir"
                      fi
                      dnl Potentially add DIR to ltrpathdirs.
                      dnl The ltrpathdirs will be appended to $LTLIBNAME at the end.
                      haveit=
                      for x in $ltrpathdirs; do
                        if test "X$x" = "X$dir"; then
                          haveit=yes
                          break
                        fi
                      done
                      if test -z "$haveit"; then
                        ltrpathdirs="$ltrpathdirs $dir"
                      fi
                    fi
                    ;;
                  -l*)
                    dnl Handle this in the next round.
                    names_next_round="$names_next_round "`echo "X$dep" | sed -e 's/^X-l//'`
                    ;;
                  *.la)
                    dnl Handle this in the next round. Throw away the .la's
                    dnl directory; it is already contained in a preceding -L
                    dnl option.
                    names_next_round="$names_next_round "`echo "X$dep" | sed -e 's,^X.*/,,' -e 's,^lib,,' -e 's,\.la$,,'`
                    ;;
                  *)
                    dnl Most likely an immediate library name.
                    LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$dep"
                    LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }$dep"
                    ;;
                esac
              done
            fi
          else
            dnl Didn't find the library; assume it is in the system directories
            dnl known to the linker and runtime loader. (All the system
            dnl directories known to the linker should also be known to the
            dnl runtime loader, otherwise the system is severely misconfigured.)
            LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-l$name"
            LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-l$name"
          fi
        fi
      fi
    done
  done
  if test "X$rpathdirs" != "X"; then
    if test -n "$acl_hardcode_libdir_separator"; then
      dnl Weird platform: only the last -rpath option counts, the user must
      dnl pass all path elements in one option. We can arrange that for a
      dnl single library, but not when more than one $LIBNAMEs are used.
      alldirs=
      for found_dir in $rpathdirs; do
        alldirs="${alldirs}${alldirs:+$acl_hardcode_libdir_separator}$found_dir"
      done
      dnl Note: acl_hardcode_libdir_flag_spec uses $libdir and $wl.
      acl_save_libdir="$libdir"
      libdir="$alldirs"
      eval flag=\"$acl_hardcode_libdir_flag_spec\"
      libdir="$acl_save_libdir"
      LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$flag"
    else
      dnl The -rpath options are cumulative.
      for found_dir in $rpathdirs; do
        acl_save_libdir="$libdir"
        libdir="$found_dir"
        eval flag=\"$acl_hardcode_libdir_flag_spec\"
        libdir="$acl_save_libdir"
        LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$flag"
      done
    fi
  fi
  if test "X$ltrpathdirs" != "X"; then
    dnl When using libtool, the option that works for both libraries and
    dnl executables is -R. The -R options are cumulative.
    for found_dir in $ltrpathdirs; do
      LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-R$found_dir"
    done
  fi
  popdef([PACKLIBS])
  popdef([PACKUP])
  popdef([PACK])
  popdef([NAME])
])

dnl AC_LIB_APPENDTOVAR(VAR, CONTENTS) appends the elements of CONTENTS to VAR,
dnl unless already present in VAR.
dnl Works only for CPPFLAGS, not for LIB* variables because that sometimes
dnl contains two or three consecutive elements that belong together.
AC_DEFUN([AC_LIB_APPENDTOVAR],
[
  for element in [$2]; do
    haveit=
    for x in $[$1]; do
      AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
      if test "X$x" = "X$element"; then
        haveit=yes
        break
      fi
    done
    if test -z "$haveit"; then
      [$1]="${[$1]}${[$1]:+ }$element"
    fi
  done
])

dnl For those cases where a variable contains several -L and -l options
dnl referring to unknown libraries and directories, this macro determines the
dnl necessary additional linker options for the runtime path.
dnl AC_LIB_LINKFLAGS_FROM_LIBS([LDADDVAR], [LIBSVALUE], [USE-LIBTOOL])
dnl sets LDADDVAR to linker options needed together with LIBSVALUE.
dnl If USE-LIBTOOL evaluates to non-empty, linking with libtool is assumed,
dnl otherwise linking without libtool is assumed.
AC_DEFUN([AC_LIB_LINKFLAGS_FROM_LIBS],
[
  AC_REQUIRE([AC_LIB_RPATH])
  AC_REQUIRE([AC_LIB_PREPARE_MULTILIB])
  $1=
  if test "$enable_rpath" != no; then
    if test -n "$acl_hardcode_libdir_flag_spec" && test "$acl_hardcode_minus_L" = no; then
      dnl Use an explicit option to hardcode directories into the resulting
      dnl binary.
      rpathdirs=
      next=
      for opt in $2; do
        if test -n "$next"; then
          dir="$next"
          dnl No need to hardcode the standard /usr/lib.
          if test "X$dir" != "X/usr/$acl_libdirstem" \
             && test "X$dir" != "X/usr/$acl_libdirstem2" \
             && test "X$dir" != "X/usr/$acl_libdirstem3"; then
            rpathdirs="$rpathdirs $dir"
          fi
          next=
        else
          case $opt in
            -L) next=yes ;;
            -L*) dir=`echo "X$opt" | sed -e 's,^X-L,,'`
                 dnl No need to hardcode the standard /usr/lib.
                 if test "X$dir" != "X/usr/$acl_libdirstem" \
                    && test "X$dir" != "X/usr/$acl_libdirstem2" \
                    && test "X$dir" != "X/usr/$acl_libdirstem3"; then
                   rpathdirs="$rpathdirs $dir"
                 fi
                 next= ;;
            *) next= ;;
          esac
        fi
      done
      if test "X$rpathdirs" != "X"; then
        if test -n ""$3""; then
          dnl libtool is used for linking. Use -R options.
          for dir in $rpathdirs; do
            $1="${$1}${$1:+ }-R$dir"
          done
        else
          dnl The linker is used for linking directly.
          if test -n "$acl_hardcode_libdir_separator"; then
            dnl Weird platform: only the last -rpath option counts, the user
            dnl must pass all path elements in one option.
            alldirs=
            for dir in $rpathdirs; do
              alldirs="${alldirs}${alldirs:+$acl_hardcode_libdir_separator}$dir"
            done
            acl_save_libdir="$libdir"
            libdir="$alldirs"
            eval flag=\"$acl_hardcode_libdir_flag_spec\"
            libdir="$acl_save_libdir"
            $1="$flag"
          else
            dnl The -rpath options are cumulative.
            for dir in $rpathdirs; do
              acl_save_libdir="$libdir"
              libdir="$dir"
              eval flag=\"$acl_hardcode_libdir_flag_spec\"
              libdir="$acl_save_libdir"
              $1="${$1}${$1:+ }$flag"
            done
          fi
        fi
      fi
    fi
  fi
  AC_SUBST([$1])
])

# lib-prefix.m4 serial 17
dnl Copyright (C) 2001-2005, 2008-2020 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 From Bruno Haible.

dnl AC_LIB_PREFIX adds to the CPPFLAGS and LDFLAGS the flags that are needed
dnl to access previously installed libraries. The basic assumption is that
dnl a user will want packages to use other packages he previously installed
dnl with the same --prefix option.
dnl This macro is not needed if only AC_LIB_LINKFLAGS is used to locate
dnl libraries, but is otherwise very convenient.
AC_DEFUN([AC_LIB_PREFIX],
[
  AC_BEFORE([$0], [AC_LIB_LINKFLAGS])
  AC_REQUIRE([AC_PROG_CC])
  AC_REQUIRE([AC_CANONICAL_HOST])
  AC_REQUIRE([AC_LIB_PREPARE_MULTILIB])
  AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
  dnl By default, look in $includedir and $libdir.
  use_additional=yes
  AC_LIB_WITH_FINAL_PREFIX([
    eval additional_includedir=\"$includedir\"
    eval additional_libdir=\"$libdir\"
  ])
  AC_ARG_WITH([lib-prefix],
[[  --with-lib-prefix[=DIR] search for libraries in DIR/include and DIR/lib
  --without-lib-prefix    don't search for libraries in includedir and libdir]],
[
    if test "X$withval" = "Xno"; then
      use_additional=no
    else
      if test "X$withval" = "X"; then
        AC_LIB_WITH_FINAL_PREFIX([
          eval additional_includedir=\"$includedir\"
          eval additional_libdir=\"$libdir\"
        ])
      else
        additional_includedir="$withval/include"
        additional_libdir="$withval/$acl_libdirstem"
      fi
    fi
])
  if test $use_additional = yes; then
    dnl Potentially add $additional_includedir to $CPPFLAGS.
    dnl But don't add it
    dnl   1. if it's the standard /usr/include,
    dnl   2. if it's already present in $CPPFLAGS,
    dnl   3. if it's /usr/local/include and we are using GCC on Linux,
    dnl   4. if it doesn't exist as a directory.
    if test "X$additional_includedir" != "X/usr/include"; then
      haveit=
      for x in $CPPFLAGS; do
        AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
        if test "X$x" = "X-I$additional_includedir"; then
          haveit=yes
          break
        fi
      done
      if test -z "$haveit"; then
        if test "X$additional_includedir" = "X/usr/local/include"; then
          if test -n "$GCC"; then
            case $host_os in
              linux* | gnu* | k*bsd*-gnu) haveit=yes;;
            esac
          fi
        fi
        if test -z "$haveit"; then
          if test -d "$additional_includedir"; then
            dnl Really add $additional_includedir to $CPPFLAGS.
            CPPFLAGS="${CPPFLAGS}${CPPFLAGS:+ }-I$additional_includedir"
          fi
        fi
      fi
    fi
    dnl Potentially add $additional_libdir to $LDFLAGS.
    dnl But don't add it
    dnl   1. if it's the standard /usr/lib,
    dnl   2. if it's already present in $LDFLAGS,
    dnl   3. if it's /usr/local/lib and we are using GCC on Linux,
    dnl   4. if it doesn't exist as a directory.
    if test "X$additional_libdir" != "X/usr/$acl_libdirstem"; then
      haveit=
      for x in $LDFLAGS; do
        AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
        if test "X$x" = "X-L$additional_libdir"; then
          haveit=yes
          break
        fi
      done
      if test -z "$haveit"; then
        if test "X$additional_libdir" = "X/usr/local/$acl_libdirstem"; then
          if test -n "$GCC"; then
            case $host_os in
              linux*) haveit=yes;;
            esac
          fi
        fi
        if test -z "$haveit"; then
          if test -d "$additional_libdir"; then
            dnl Really add $additional_libdir to $LDFLAGS.
            LDFLAGS="${LDFLAGS}${LDFLAGS:+ }-L$additional_libdir"
          fi
        fi
      fi
    fi
  fi
])

dnl AC_LIB_PREPARE_PREFIX creates variables acl_final_prefix,
dnl acl_final_exec_prefix, containing the values to which $prefix and
dnl $exec_prefix will expand at the end of the configure script.
AC_DEFUN([AC_LIB_PREPARE_PREFIX],
[
  dnl Unfortunately, prefix and exec_prefix get only finally determined
  dnl at the end of configure.
  if test "X$prefix" = "XNONE"; then
    acl_final_prefix="$ac_default_prefix"
  else
    acl_final_prefix="$prefix"
  fi
  if test "X$exec_prefix" = "XNONE"; then
    acl_final_exec_prefix='${prefix}'
  else
    acl_final_exec_prefix="$exec_prefix"
  fi
  acl_save_prefix="$prefix"
  prefix="$acl_final_prefix"
  eval acl_final_exec_prefix=\"$acl_final_exec_prefix\"
  prefix="$acl_save_prefix"
])

dnl AC_LIB_WITH_FINAL_PREFIX([statement]) evaluates statement, with the
dnl variables prefix and exec_prefix bound to the values they will have
dnl at the end of the configure script.
AC_DEFUN([AC_LIB_WITH_FINAL_PREFIX],
[
  acl_save_prefix="$prefix"
  prefix="$acl_final_prefix"
  acl_save_exec_prefix="$exec_prefix"
  exec_prefix="$acl_final_exec_prefix"
  $1
  exec_prefix="$acl_save_exec_prefix"
  prefix="$acl_save_prefix"
])

dnl AC_LIB_PREPARE_MULTILIB creates
dnl - a function acl_is_expected_elfclass, that tests whether standard input
dn;   has a 32-bit or 64-bit ELF header, depending on the host CPU ABI,
dnl - 3 variables acl_libdirstem, acl_libdirstem2, acl_libdirstem3, containing
dnl   the basename of the libdir to try in turn, either "lib" or "lib64" or
dnl   "lib/64" or "lib32" or "lib/sparcv9" or "lib/amd64" or similar.
AC_DEFUN([AC_LIB_PREPARE_MULTILIB],
[
  dnl There is no formal standard regarding lib, lib32, and lib64.
  dnl On most glibc systems, the current practice is that on a system supporting
  dnl 32-bit and 64-bit instruction sets or ABIs, 64-bit libraries go under
  dnl $prefix/lib64 and 32-bit libraries go under $prefix/lib. However, on
  dnl Arch Linux based distributions, it's the opposite: 32-bit libraries go
  dnl under $prefix/lib32 and 64-bit libraries go under $prefix/lib.
  dnl We determine the compiler's default mode by looking at the compiler's
  dnl library search path. If at least one of its elements ends in /lib64 or
  dnl points to a directory whose absolute pathname ends in /lib64, we use that
  dnl for 64-bit ABIs. Similarly for 32-bit ABIs. Otherwise we use the default,
  dnl namely "lib".
  dnl On Solaris systems, the current practice is that on a system supporting
  dnl 32-bit and 64-bit instruction sets or ABIs, 64-bit libraries go under
  dnl $prefix/lib/64 (which is a symlink to either $prefix/lib/sparcv9 or
  dnl $prefix/lib/amd64) and 32-bit libraries go under $prefix/lib.
  AC_REQUIRE([AC_CANONICAL_HOST])
  AC_REQUIRE([gl_HOST_CPU_C_ABI_32BIT])

  AC_CACHE_CHECK([for ELF binary format], [gl_cv_elf],
    [AC_EGREP_CPP([Extensible Linking Format],
       [#ifdef __ELF__
        Extensible Linking Format
        #endif
       ],
       [gl_cv_elf=yes],
       [gl_cv_elf=no])
     ])
  if test $gl_cv_elf; then
    # Extract the ELF class of a file (5th byte) in decimal.
    # Cf. https://en.wikipedia.org/wiki/Executable_and_Linkable_Format#File_header
    if od -A x < /dev/null >/dev/null 2>/dev/null; then
      # Use POSIX od.
      func_elfclass ()
      {
        od -A n -t d1 -j 4 -N 1
      }
    else
      # Use BSD hexdump.
      func_elfclass ()
      {
        dd bs=1 count=1 skip=4 2>/dev/null | hexdump -e '1/1 "%3d "'
        echo
      }
    fi
changequote(,)dnl
    case $HOST_CPU_C_ABI_32BIT in
      yes)
        # 32-bit ABI.
        acl_is_expected_elfclass ()
        {
          test "`func_elfclass | sed -e 's/[ 	]//g'`" = 1
        }
        ;;
      no)
        # 64-bit ABI.
        acl_is_expected_elfclass ()
        {
          test "`func_elfclass | sed -e 's/[ 	]//g'`" = 2
        }
        ;;
      *)
        # Unknown.
        acl_is_expected_elfclass ()
        {
          :
        }
        ;;
    esac
changequote([,])dnl
  else
    acl_is_expected_elfclass ()
    {
      :
    }
  fi

  dnl Allow the user to override the result by setting acl_cv_libdirstems.
  AC_CACHE_CHECK([for the common suffixes of directories in the library search path],
    [acl_cv_libdirstems],
    [dnl Try 'lib' first, because that's the default for libdir in GNU, see
     dnl <https://www.gnu.org/prep/standards/html_node/Directory-Variables.html>.
     acl_libdirstem=lib
     acl_libdirstem2=
     acl_libdirstem3=
     case "$host_os" in
       solaris*)
         dnl See Solaris 10 Software Developer Collection > Solaris 64-bit Developer's Guide > The Development Environment
         dnl <https://docs.oracle.com/cd/E19253-01/816-5138/dev-env/index.html>.
         dnl "Portable Makefiles should refer to any library directories using the 64 symbolic link."
         dnl But we want to recognize the sparcv9 or amd64 subdirectory also if the
         dnl symlink is missing, so we set acl_libdirstem2 too.
         if test $HOST_CPU_C_ABI_32BIT = no; then
           acl_libdirstem2=lib/64
           case "$host_cpu" in
             sparc*)        acl_libdirstem3=lib/sparcv9 ;;
             i*86 | x86_64) acl_libdirstem3=lib/amd64 ;;
           esac
         fi
         ;;
       *)
         dnl If $CC generates code for a 32-bit ABI, the libraries are
         dnl surely under $prefix/lib or $prefix/lib32, not $prefix/lib64.
         dnl Similarly, if $CC generates code for a 64-bit ABI, the libraries
         dnl are surely under $prefix/lib or $prefix/lib64, not $prefix/lib32.
         dnl Find the compiler's search path. However, non-system compilers
         dnl sometimes have odd library search paths. But we can't simply invoke
         dnl '/usr/bin/gcc -print-search-dirs' because that would not take into
         dnl account the -m32/-m31 or -m64 options from the $CC or $CFLAGS.
         searchpath=`(LC_ALL=C $CC $CPPFLAGS $CFLAGS -print-search-dirs) 2>/dev/null \
                     | sed -n -e 's,^libraries: ,,p' | sed -e 's,^=,,'`
         if test $HOST_CPU_C_ABI_32BIT != no; then
           # 32-bit or unknown ABI.
           if test -d /usr/lib32; then
             acl_libdirstem2=lib32
           fi
         fi
         if test $HOST_CPU_C_ABI_32BIT != yes; then
           # 64-bit or unknown ABI.
           if test -d /usr/lib64; then
             acl_libdirstem3=lib64
           fi
         fi
         if test -n "$searchpath"; then
           acl_save_IFS="${IFS= 	}"; IFS=":"
           for searchdir in $searchpath; do
             if test -d "$searchdir"; then
               case "$searchdir" in
                 */lib32/ | */lib32 ) acl_libdirstem2=lib32 ;;
                 */lib64/ | */lib64 ) acl_libdirstem3=lib64 ;;
                 */../ | */.. )
                   # Better ignore directories of this form. They are misleading.
                   ;;
                 *) searchdir=`cd "$searchdir" && pwd`
                    case "$searchdir" in
                      */lib32 ) acl_libdirstem2=lib32 ;;
                      */lib64 ) acl_libdirstem3=lib64 ;;
                    esac ;;
               esac
             fi
           done
           IFS="$acl_save_IFS"
           if test $HOST_CPU_C_ABI_32BIT = yes; then
             # 32-bit ABI.
             acl_libdirstem3=
           fi
           if test $HOST_CPU_C_ABI_32BIT = no; then
             # 64-bit ABI.
             acl_libdirstem2=
           fi
         fi
         ;;
     esac
     test -n "$acl_libdirstem2" || acl_libdirstem2="$acl_libdirstem"
     test -n "$acl_libdirstem3" || acl_libdirstem3="$acl_libdirstem"
     acl_cv_libdirstems="$acl_libdirstem,$acl_libdirstem2,$acl_libdirstem3"
    ])
  dnl Decompose acl_cv_libdirstems into acl_libdirstem, acl_libdirstem2, and
  dnl acl_libdirstem3.
changequote(,)dnl
  acl_libdirstem=`echo "$acl_cv_libdirstems" | sed -e 's/,.*//'`
  acl_libdirstem2=`echo "$acl_cv_libdirstems" | sed -e 's/^[^,]*,//' -e 's/,.*//'`
  acl_libdirstem3=`echo "$acl_cv_libdirstems" | sed -e 's/^[^,]*,[^,]*,//' -e 's/,.*//'`
changequote([,])dnl
])

m4_include([m4/ax_check_compile_flag.m4])
