aclocal.m4

# generated automatically by aclocal 1.16.3 -*- Autoconf -*-

# Copyright (C) 1996-2020 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($@)])])
# ===========================================================================
#  https://www.gnu.org/software/autoconf-archive/ax_cxx_compile_stdcxx.html
# ===========================================================================
#
# SYNOPSIS
#
#   AX_CXX_COMPILE_STDCXX(VERSION, [ext|noext], [mandatory|optional])
#
# DESCRIPTION
#
#   Check for baseline language coverage in the compiler for the specified
#   version of the C++ standard.  If necessary, add switches to CXX and
#   CXXCPP to enable support.  VERSION may be '11' (for the C++11 standard)
#   or '14' (for the C++14 standard).
#
#   The second argument, if specified, indicates whether you insist on an
#   extended mode (e.g. -std=gnu++11) or a strict conformance mode (e.g.
#   -std=c++11).  If neither is specified, you get whatever works, with
#   preference for an extended mode.
#
#   The third argument, if specified 'mandatory' or if left unspecified,
#   indicates that baseline support for the specified C++ standard is
#   required and that the macro should error out if no mode with that
#   support is found.  If specified 'optional', then configuration proceeds
#   regardless, after defining HAVE_CXX${VERSION} if and only if a
#   supporting mode is found.
#
# LICENSE
#
#   Copyright (c) 2008 Benjamin Kosnik <bkoz@redhat.com>
#   Copyright (c) 2012 Zack Weinberg <zackw@panix.com>
#   Copyright (c) 2013 Roy Stogner <roystgnr@ices.utexas.edu>
#   Copyright (c) 2014, 2015 Google Inc.; contributed by Alexey Sokolov <sokolov@google.com>
#   Copyright (c) 2015 Paul Norman <penorman@mac.com>
#   Copyright (c) 2015 Moritz Klammler <moritz@klammler.eu>
#   Copyright (c) 2016, 2018 Krzesimir Nowak <qdlacz@gmail.com>
#
#   Copying and distribution of this file, with or without modification, are
#   permitted in any medium without royalty provided the copyright notice
#   and this notice are preserved.  This file is offered as-is, without any
#   warranty.

#serial 10

dnl  This macro is based on the code from the AX_CXX_COMPILE_STDCXX_11 macro
dnl  (serial version number 13).

AC_DEFUN([AX_CXX_COMPILE_STDCXX], [dnl
  m4_if([$1], [11], [ax_cxx_compile_alternatives="11 0x"],
        [$1], [14], [ax_cxx_compile_alternatives="14 1y"],
        [$1], [17], [ax_cxx_compile_alternatives="17 1z"],
        [m4_fatal([invalid first argument `$1' to AX_CXX_COMPILE_STDCXX])])dnl
  m4_if([$2], [], [],
        [$2], [ext], [],
        [$2], [noext], [],
        [m4_fatal([invalid second argument `$2' to AX_CXX_COMPILE_STDCXX])])dnl
  m4_if([$3], [], [ax_cxx_compile_cxx$1_required=true],
        [$3], [mandatory], [ax_cxx_compile_cxx$1_required=true],
        [$3], [optional], [ax_cxx_compile_cxx$1_required=false],
        [m4_fatal([invalid third argument `$3' to AX_CXX_COMPILE_STDCXX])])
  AC_LANG_PUSH([C++])dnl
  ac_success=no

  m4_if([$2], [noext], [], [dnl
  if test x$ac_success = xno; then
    for alternative in ${ax_cxx_compile_alternatives}; do
      switch="-std=gnu++${alternative}"
      cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx$1_$switch])
      AC_CACHE_CHECK(whether $CXX supports C++$1 features with $switch,
                     $cachevar,
        [ac_save_CXX="$CXX"
         CXX="$CXX $switch"
         AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_testbody_$1])],
          [eval $cachevar=yes],
          [eval $cachevar=no])
         CXX="$ac_save_CXX"])
      if eval test x\$$cachevar = xyes; then
        CXX="$CXX $switch"
        if test -n "$CXXCPP" ; then
          CXXCPP="$CXXCPP $switch"
        fi
        ac_success=yes
        break
      fi
    done
  fi])

  m4_if([$2], [ext], [], [dnl
  if test x$ac_success = xno; then
    dnl HP's aCC needs +std=c++11 according to:
    dnl http://h21007.www2.hp.com/portal/download/files/unprot/aCxx/PDF_Release_Notes/769149-001.pdf
    dnl Cray's crayCC needs "-h std=c++11"
    for alternative in ${ax_cxx_compile_alternatives}; do
      for switch in -std=c++${alternative} +std=c++${alternative} "-h std=c++${alternative}"; do
        cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx$1_$switch])
        AC_CACHE_CHECK(whether $CXX supports C++$1 features with $switch,
                       $cachevar,
          [ac_save_CXX="$CXX"
           CXX="$CXX $switch"
           AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_testbody_$1])],
            [eval $cachevar=yes],
            [eval $cachevar=no])
           CXX="$ac_save_CXX"])
        if eval test x\$$cachevar = xyes; then
          CXX="$CXX $switch"
          if test -n "$CXXCPP" ; then
            CXXCPP="$CXXCPP $switch"
          fi
          ac_success=yes
          break
        fi
      done
      if test x$ac_success = xyes; then
        break
      fi
    done
  fi])
  AC_LANG_POP([C++])
  if test x$ax_cxx_compile_cxx$1_required = xtrue; then
    if test x$ac_success = xno; then
      AC_MSG_ERROR([*** A compiler with support for C++$1 language features is required.])
    fi
  fi
  if test x$ac_success = xno; then
    HAVE_CXX$1=0
    AC_MSG_NOTICE([No compiler with C++$1 support was found])
  else
    HAVE_CXX$1=1
    AC_DEFINE(HAVE_CXX$1,1,
              [define if the compiler supports basic C++$1 syntax])
  fi
  AC_SUBST(HAVE_CXX$1)
])


dnl  Test body for checking C++11 support

m4_define([_AX_CXX_COMPILE_STDCXX_testbody_11],
  _AX_CXX_COMPILE_STDCXX_testbody_new_in_11
)


dnl  Test body for checking C++14 support

m4_define([_AX_CXX_COMPILE_STDCXX_testbody_14],
  _AX_CXX_COMPILE_STDCXX_testbody_new_in_11
  _AX_CXX_COMPILE_STDCXX_testbody_new_in_14
)

m4_define([_AX_CXX_COMPILE_STDCXX_testbody_17],
  _AX_CXX_COMPILE_STDCXX_testbody_new_in_11
  _AX_CXX_COMPILE_STDCXX_testbody_new_in_14
  _AX_CXX_COMPILE_STDCXX_testbody_new_in_17
)

dnl  Tests for new features in C++11

m4_define([_AX_CXX_COMPILE_STDCXX_testbody_new_in_11], [[

// If the compiler admits that it is not ready for C++11, why torture it?
// Hopefully, this will speed up the test.

#ifndef __cplusplus

#error "This is not a C++ compiler"

#elif __cplusplus < 201103L

#error "This is not a C++11 compiler"

#else

namespace cxx11
{

  namespace test_static_assert
  {

    template <typename T>
    struct check
    {
      static_assert(sizeof(int) <= sizeof(T), "not big enough");
    };

  }

  namespace test_final_override
  {

    struct Base
    {
      virtual void f() {}
    };

    struct Derived : public Base
    {
      virtual void f() override {}
    };

  }

  namespace test_double_right_angle_brackets
  {

    template < typename T >
    struct check {};

    typedef check<void> single_type;
    typedef check<check<void>> double_type;
    typedef check<check<check<void>>> triple_type;
    typedef check<check<check<check<void>>>> quadruple_type;

  }

  namespace test_decltype
  {

    int
    f()
    {
      int a = 1;
      decltype(a) b = 2;
      return a + b;
    }

  }

  namespace test_type_deduction
  {

    template < typename T1, typename T2 >
    struct is_same
    {
      static const bool value = false;
    };

    template < typename T >
    struct is_same<T, T>
    {
      static const bool value = true;
    };

    template < typename T1, typename T2 >
    auto
    add(T1 a1, T2 a2) -> decltype(a1 + a2)
    {
      return a1 + a2;
    }

    int
    test(const int c, volatile int v)
    {
      static_assert(is_same<int, decltype(0)>::value == true, "");
      static_assert(is_same<int, decltype(c)>::value == false, "");
      static_assert(is_same<int, decltype(v)>::value == false, "");
      auto ac = c;
      auto av = v;
      auto sumi = ac + av + 'x';
      auto sumf = ac + av + 1.0;
      static_assert(is_same<int, decltype(ac)>::value == true, "");
      static_assert(is_same<int, decltype(av)>::value == true, "");
      static_assert(is_same<int, decltype(sumi)>::value == true, "");
      static_assert(is_same<int, decltype(sumf)>::value == false, "");
      static_assert(is_same<int, decltype(add(c, v))>::value == true, "");
      return (sumf > 0.0) ? sumi : add(c, v);
    }

  }

  namespace test_noexcept
  {

    int f() { return 0; }
    int g() noexcept { return 0; }

    static_assert(noexcept(f()) == false, "");
    static_assert(noexcept(g()) == true, "");

  }

  namespace test_constexpr
  {

    template < typename CharT >
    unsigned long constexpr
    strlen_c_r(const CharT *const s, const unsigned long acc) noexcept
    {
      return *s ? strlen_c_r(s + 1, acc + 1) : acc;
    }

    template < typename CharT >
    unsigned long constexpr
    strlen_c(const CharT *const s) noexcept
    {
      return strlen_c_r(s, 0UL);
    }

    static_assert(strlen_c("") == 0UL, "");
    static_assert(strlen_c("1") == 1UL, "");
    static_assert(strlen_c("example") == 7UL, "");
    static_assert(strlen_c("another\0example") == 7UL, "");

  }

  namespace test_rvalue_references
  {

    template < int N >
    struct answer
    {
      static constexpr int value = N;
    };

    answer<1> f(int&)       { return answer<1>(); }
    answer<2> f(const int&) { return answer<2>(); }
    answer<3> f(int&&)      { return answer<3>(); }

    void
    test()
    {
      int i = 0;
      const int c = 0;
      static_assert(decltype(f(i))::value == 1, "");
      static_assert(decltype(f(c))::value == 2, "");
      static_assert(decltype(f(0))::value == 3, "");
    }

  }

  namespace test_uniform_initialization
  {

    struct test
    {
      static const int zero {};
      static const int one {1};
    };

    static_assert(test::zero == 0, "");
    static_assert(test::one == 1, "");

  }

  namespace test_lambdas
  {

    void
    test1()
    {
      auto lambda1 = [](){};
      auto lambda2 = lambda1;
      lambda1();
      lambda2();
    }

    int
    test2()
    {
      auto a = [](int i, int j){ return i + j; }(1, 2);
      auto b = []() -> int { return '0'; }();
      auto c = [=](){ return a + b; }();
      auto d = [&](){ return c; }();
      auto e = [a, &b](int x) mutable {
        const auto identity = [](int y){ return y; };
        for (auto i = 0; i < a; ++i)
          a += b--;
        return x + identity(a + b);
      }(0);
      return a + b + c + d + e;
    }

    int
    test3()
    {
      const auto nullary = [](){ return 0; };
      const auto unary = [](int x){ return x; };
      using nullary_t = decltype(nullary);
      using unary_t = decltype(unary);
      const auto higher1st = [](nullary_t f){ return f(); };
      const auto higher2nd = [unary](nullary_t f1){
        return [unary, f1](unary_t f2){ return f2(unary(f1())); };
      };
      return higher1st(nullary) + higher2nd(nullary)(unary);
    }

  }

  namespace test_variadic_templates
  {

    template <int...>
    struct sum;

    template <int N0, int... N1toN>
    struct sum<N0, N1toN...>
    {
      static constexpr auto value = N0 + sum<N1toN...>::value;
    };

    template <>
    struct sum<>
    {
      static constexpr auto value = 0;
    };

    static_assert(sum<>::value == 0, "");
    static_assert(sum<1>::value == 1, "");
    static_assert(sum<23>::value == 23, "");
    static_assert(sum<1, 2>::value == 3, "");
    static_assert(sum<5, 5, 11>::value == 21, "");
    static_assert(sum<2, 3, 5, 7, 11, 13>::value == 41, "");

  }

  // http://stackoverflow.com/questions/13728184/template-aliases-and-sfinae
  // Clang 3.1 fails with headers of libstd++ 4.8.3 when using std::function
  // because of this.
  namespace test_template_alias_sfinae
  {

    struct foo {};

    template<typename T>
    using member = typename T::member_type;

    template<typename T>
    void func(...) {}

    template<typename T>
    void func(member<T>*) {}

    void test();

    void test() { func<foo>(0); }

  }

}  // namespace cxx11

#endif  // __cplusplus >= 201103L

]])


dnl  Tests for new features in C++14

m4_define([_AX_CXX_COMPILE_STDCXX_testbody_new_in_14], [[

// If the compiler admits that it is not ready for C++14, why torture it?
// Hopefully, this will speed up the test.

#ifndef __cplusplus

#error "This is not a C++ compiler"

#elif __cplusplus < 201402L

#error "This is not a C++14 compiler"

#else

namespace cxx14
{

  namespace test_polymorphic_lambdas
  {

    int
    test()
    {
      const auto lambda = [](auto&&... args){
        const auto istiny = [](auto x){
          return (sizeof(x) == 1UL) ? 1 : 0;
        };
        const int aretiny[] = { istiny(args)... };
        return aretiny[0];
      };
      return lambda(1, 1L, 1.0f, '1');
    }

  }

  namespace test_binary_literals
  {

    constexpr auto ivii = 0b0000000000101010;
    static_assert(ivii == 42, "wrong value");

  }

  namespace test_generalized_constexpr
  {

    template < typename CharT >
    constexpr unsigned long
    strlen_c(const CharT *const s) noexcept
    {
      auto length = 0UL;
      for (auto p = s; *p; ++p)
        ++length;
      return length;
    }

    static_assert(strlen_c("") == 0UL, "");
    static_assert(strlen_c("x") == 1UL, "");
    static_assert(strlen_c("test") == 4UL, "");
    static_assert(strlen_c("another\0test") == 7UL, "");

  }

  namespace test_lambda_init_capture
  {

    int
    test()
    {
      auto x = 0;
      const auto lambda1 = [a = x](int b){ return a + b; };
      const auto lambda2 = [a = lambda1(x)](){ return a; };
      return lambda2();
    }

  }

  namespace test_digit_separators
  {

    constexpr auto ten_million = 100'000'000;
    static_assert(ten_million == 100000000, "");

  }

  namespace test_return_type_deduction
  {

    auto f(int& x) { return x; }
    decltype(auto) g(int& x) { return x; }

    template < typename T1, typename T2 >
    struct is_same
    {
      static constexpr auto value = false;
    };

    template < typename T >
    struct is_same<T, T>
    {
      static constexpr auto value = true;
    };

    int
    test()
    {
      auto x = 0;
      static_assert(is_same<int, decltype(f(x))>::value, "");
      static_assert(is_same<int&, decltype(g(x))>::value, "");
      return x;
    }

  }

}  // namespace cxx14

#endif  // __cplusplus >= 201402L

]])


dnl  Tests for new features in C++17

m4_define([_AX_CXX_COMPILE_STDCXX_testbody_new_in_17], [[

// If the compiler admits that it is not ready for C++17, why torture it?
// Hopefully, this will speed up the test.

#ifndef __cplusplus

#error "This is not a C++ compiler"

#elif __cplusplus < 201703L

#error "This is not a C++17 compiler"

#else

#include <initializer_list>
#include <utility>
#include <type_traits>

namespace cxx17
{

  namespace test_constexpr_lambdas
  {

    constexpr int foo = [](){return 42;}();

  }

  namespace test::nested_namespace::definitions
  {

  }

  namespace test_fold_expression
  {

    template<typename... Args>
    int multiply(Args... args)
    {
      return (args * ... * 1);
    }

    template<typename... Args>
    bool all(Args... args)
    {
      return (args && ...);
    }

  }

  namespace test_extended_static_assert
  {

    static_assert (true);

  }

  namespace test_auto_brace_init_list
  {

    auto foo = {5};
    auto bar {5};

    static_assert(std::is_same<std::initializer_list<int>, decltype(foo)>::value);
    static_assert(std::is_same<int, decltype(bar)>::value);
  }

  namespace test_typename_in_template_template_parameter
  {

    template<template<typename> typename X> struct D;

  }

  namespace test_fallthrough_nodiscard_maybe_unused_attributes
  {

    int f1()
    {
      return 42;
    }

    [[nodiscard]] int f2()
    {
      [[maybe_unused]] auto unused = f1();

      switch (f1())
      {
      case 17:
        f1();
        [[fallthrough]];
      case 42:
        f1();
      }
      return f1();
    }

  }

  namespace test_extended_aggregate_initialization
  {

    struct base1
    {
      int b1, b2 = 42;
    };

    struct base2
    {
      base2() {
        b3 = 42;
      }
      int b3;
    };

    struct derived : base1, base2
    {
        int d;
    };

    derived d1 {{1, 2}, {}, 4};  // full initialization
    derived d2 {{}, {}, 4};      // value-initialized bases

  }

  namespace test_general_range_based_for_loop
  {

    struct iter
    {
      int i;

      int& operator* ()
      {
        return i;
      }

      const int& operator* () const
      {
        return i;
      }

      iter& operator++()
      {
        ++i;
        return *this;
      }
    };

    struct sentinel
    {
      int i;
    };

    bool operator== (const iter& i, const sentinel& s)
    {
      return i.i == s.i;
    }

    bool operator!= (const iter& i, const sentinel& s)
    {
      return !(i == s);
    }

    struct range
    {
      iter begin() const
      {
        return {0};
      }

      sentinel end() const
      {
        return {5};
      }
    };

    void f()
    {
      range r {};

      for (auto i : r)
      {
        [[maybe_unused]] auto v = i;
      }
    }

  }

  namespace test_lambda_capture_asterisk_this_by_value
  {

    struct t
    {
      int i;
      int foo()
      {
        return [*this]()
        {
          return i;
        }();
      }
    };

  }

  namespace test_enum_class_construction
  {

    enum class byte : unsigned char
    {};

    byte foo {42};

  }

  namespace test_constexpr_if
  {

    template <bool cond>
    int f ()
    {
      if constexpr(cond)
      {
        return 13;
      }
      else
      {
        return 42;
      }
    }

  }

  namespace test_selection_statement_with_initializer
  {

    int f()
    {
      return 13;
    }

    int f2()
    {
      if (auto i = f(); i > 0)
      {
        return 3;
      }

      switch (auto i = f(); i + 4)
      {
      case 17:
        return 2;

      default:
        return 1;
      }
    }

  }

  namespace test_template_argument_deduction_for_class_templates
  {

    template <typename T1, typename T2>
    struct pair
    {
      pair (T1 p1, T2 p2)
        : m1 {p1},
          m2 {p2}
      {}

      T1 m1;
      T2 m2;
    };

    void f()
    {
      [[maybe_unused]] auto p = pair{13, 42u};
    }

  }

  namespace test_non_type_auto_template_parameters
  {

    template <auto n>
    struct B
    {};

    B<5> b1;
    B<'a'> b2;

  }

  namespace test_structured_bindings
  {

    int arr[2] = { 1, 2 };
    std::pair<int, int> pr = { 1, 2 };

    auto f1() -> int(&)[2]
    {
      return arr;
    }

    auto f2() -> std::pair<int, int>&
    {
      return pr;
    }

    struct S
    {
      int x1 : 2;
      volatile double y1;
    };

    S f3()
    {
      return {};
    }

    auto [ x1, y1 ] = f1();
    auto& [ xr1, yr1 ] = f1();
    auto [ x2, y2 ] = f2();
    auto& [ xr2, yr2 ] = f2();
    const auto [ x3, y3 ] = f3();

  }

  namespace test_exception_spec_type_system
  {

    struct Good {};
    struct Bad {};

    void g1() noexcept;
    void g2();

    template<typename T>
    Bad
    f(T*, T*);

    template<typename T1, typename T2>
    Good
    f(T1*, T2*);

    static_assert (std::is_same_v<Good, decltype(f(g1, g2))>);

  }

  namespace test_inline_variables
  {

    template<class T> void f(T)
    {}

    template<class T> inline T g(T)
    {
      return T{};
    }

    template<> inline void f<>(int)
    {}

    template<> int g<>(int)
    {
      return 5;
    }

  }

}  // namespace cxx17

#endif  // __cplusplus < 201703L

]])

# =============================================================================
#  https://www.gnu.org/software/autoconf-archive/ax_cxx_compile_stdcxx_11.html
# =============================================================================
#
# SYNOPSIS
#
#   AX_CXX_COMPILE_STDCXX_11([ext|noext], [mandatory|optional])
#
# DESCRIPTION
#
#   Check for baseline language coverage in the compiler for the C++11
#   standard; if necessary, add switches to CXX and CXXCPP to enable
#   support.
#
#   This macro is a convenience alias for calling the AX_CXX_COMPILE_STDCXX
#   macro with the version set to C++11.  The two optional arguments are
#   forwarded literally as the second and third argument respectively.
#   Please see the documentation for the AX_CXX_COMPILE_STDCXX macro for
#   more information.  If you want to use this macro, you also need to
#   download the ax_cxx_compile_stdcxx.m4 file.
#
# LICENSE
#
#   Copyright (c) 2008 Benjamin Kosnik <bkoz@redhat.com>
#   Copyright (c) 2012 Zack Weinberg <zackw@panix.com>
#   Copyright (c) 2013 Roy Stogner <roystgnr@ices.utexas.edu>
#   Copyright (c) 2014, 2015 Google Inc.; contributed by Alexey Sokolov <sokolov@google.com>
#   Copyright (c) 2015 Paul Norman <penorman@mac.com>
#   Copyright (c) 2015 Moritz Klammler <moritz@klammler.eu>
#
#   Copying and distribution of this file, with or without modification, are
#   permitted in any medium without royalty provided the copyright notice
#   and this notice are preserved. This file is offered as-is, without any
#   warranty.

#serial 18

AX_REQUIRE_DEFINED([AX_CXX_COMPILE_STDCXX])
AC_DEFUN([AX_CXX_COMPILE_STDCXX_11], [AX_CXX_COMPILE_STDCXX([11], [$1], [$2])])

# Copyright (C) 1999-2020 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.


# AM_PATH_PYTHON([MINIMUM-VERSION], [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND])
# ---------------------------------------------------------------------------
# Adds support for distributing Python modules and packages.  To
# install modules, copy them to $(pythondir), using the python_PYTHON
# automake variable.  To install a package with the same name as the
# automake package, install to $(pkgpythondir), or use the
# pkgpython_PYTHON automake variable.
#
# The variables $(pyexecdir) and $(pkgpyexecdir) are provided as
# locations to install python extension modules (shared libraries).
# Another macro is required to find the appropriate flags to compile
# extension modules.
#
# If your package is configured with a different prefix to python,
# users will have to add the install directory to the PYTHONPATH
# environment variable, or create a .pth file (see the python
# documentation for details).
#
# If the MINIMUM-VERSION argument is passed, AM_PATH_PYTHON will
# cause an error if the version of python installed on the system
# doesn't meet the requirement.  MINIMUM-VERSION should consist of
# numbers and dots only.
AC_DEFUN([AM_PATH_PYTHON],
 [
  dnl Find a Python interpreter.  Python versions prior to 2.0 are not
  dnl supported. (2.0 was released on October 16, 2000).
  m4_define_default([_AM_PYTHON_INTERPRETER_LIST],
[python python2 python3 dnl
 python3.9 python3.8 python3.7 python3.6 python3.5 python3.4 python3.3 dnl
 python3.2 python3.1 python3.0 dnl
 python2.7 python2.6 python2.5 python2.4 python2.3 python2.2 python2.1 dnl
 python2.0])

  AC_ARG_VAR([PYTHON], [the Python interpreter])

  m4_if([$1],[],[
    dnl No version check is needed.
    # Find any Python interpreter.
    if test -z "$PYTHON"; then
      AC_PATH_PROGS([PYTHON], _AM_PYTHON_INTERPRETER_LIST, :)
    fi
    am_display_PYTHON=python
  ], [
    dnl A version check is needed.
    if test -n "$PYTHON"; then
      # If the user set $PYTHON, use it and don't search something else.
      AC_MSG_CHECKING([whether $PYTHON version is >= $1])
      AM_PYTHON_CHECK_VERSION([$PYTHON], [$1],
			      [AC_MSG_RESULT([yes])],
			      [AC_MSG_RESULT([no])
			       AC_MSG_ERROR([Python interpreter is too old])])
      am_display_PYTHON=$PYTHON
    else
      # Otherwise, try each interpreter until we find one that satisfies
      # VERSION.
      AC_CACHE_CHECK([for a Python interpreter with version >= $1],
	[am_cv_pathless_PYTHON],[
	for am_cv_pathless_PYTHON in _AM_PYTHON_INTERPRETER_LIST none; do
	  test "$am_cv_pathless_PYTHON" = none && break
	  AM_PYTHON_CHECK_VERSION([$am_cv_pathless_PYTHON], [$1], [break])
	done])
      # Set $PYTHON to the absolute path of $am_cv_pathless_PYTHON.
      if test "$am_cv_pathless_PYTHON" = none; then
	PYTHON=:
      else
        AC_PATH_PROG([PYTHON], [$am_cv_pathless_PYTHON])
      fi
      am_display_PYTHON=$am_cv_pathless_PYTHON
    fi
  ])

  if test "$PYTHON" = :; then
  dnl Run any user-specified action, or abort.
    m4_default([$3], [AC_MSG_ERROR([no suitable Python interpreter found])])
  else

  dnl Query Python for its version number.  Although site.py simply uses
  dnl sys.version[:3], printing that failed with Python 3.10, since the
  dnl trailing zero was eliminated. So now we output just the major
  dnl and minor version numbers, as numbers. Apparently the tertiary
  dnl version is not of interest.

  AC_CACHE_CHECK([for $am_display_PYTHON version], [am_cv_python_version],
    [am_cv_python_version=`$PYTHON -c "import sys; print('%u.%u' % sys.version_info[[:2]])"`])
  AC_SUBST([PYTHON_VERSION], [$am_cv_python_version])

  dnl Use the values of $prefix and $exec_prefix for the corresponding
  dnl values of PYTHON_PREFIX and PYTHON_EXEC_PREFIX.  These are made
  dnl distinct variables so they can be overridden if need be.  However,
  dnl general consensus is that you shouldn't need this ability.

  AC_SUBST([PYTHON_PREFIX], ['${prefix}'])
  AC_SUBST([PYTHON_EXEC_PREFIX], ['${exec_prefix}'])

  dnl At times (like when building shared libraries) you may want
  dnl to know which OS platform Python thinks this is.

  AC_CACHE_CHECK([for $am_display_PYTHON platform], [am_cv_python_platform],
    [am_cv_python_platform=`$PYTHON -c "import sys; sys.stdout.write(sys.platform)"`])
  AC_SUBST([PYTHON_PLATFORM], [$am_cv_python_platform])

  # Just factor out some code duplication.
  am_python_setup_sysconfig="\
import sys
# Prefer sysconfig over distutils.sysconfig, for better compatibility
# with python 3.x.  See automake bug#10227.
try:
    import sysconfig
except ImportError:
    can_use_sysconfig = 0
else:
    can_use_sysconfig = 1
# Can't use sysconfig in CPython 2.7, since it's broken in virtualenvs:
# <https://github.com/pypa/virtualenv/issues/118>
try:
    from platform import python_implementation
    if python_implementation() == 'CPython' and sys.version[[:3]] == '2.7':
        can_use_sysconfig = 0
except ImportError:
    pass"

  dnl Set up 4 directories:

  dnl pythondir -- where to install python scripts.  This is the
  dnl   site-packages directory, not the python standard library
  dnl   directory like in previous automake betas.  This behavior
  dnl   is more consistent with lispdir.m4 for example.
  dnl Query distutils for this directory.
  AC_CACHE_CHECK([for $am_display_PYTHON script directory],
    [am_cv_python_pythondir],
    [if test "x$prefix" = xNONE
     then
       am_py_prefix=$ac_default_prefix
     else
       am_py_prefix=$prefix
     fi
     am_cv_python_pythondir=`$PYTHON -c "
$am_python_setup_sysconfig
if can_use_sysconfig:
    sitedir = sysconfig.get_path('purelib', vars={'base':'$am_py_prefix'})
else:
    from distutils import sysconfig
    sitedir = sysconfig.get_python_lib(0, 0, prefix='$am_py_prefix')
sys.stdout.write(sitedir)"`
     case $am_cv_python_pythondir in
     $am_py_prefix*)
       am__strip_prefix=`echo "$am_py_prefix" | sed 's|.|.|g'`
       am_cv_python_pythondir=`echo "$am_cv_python_pythondir" | sed "s,^$am__strip_prefix,$PYTHON_PREFIX,"`
       ;;
     *)
       case $am_py_prefix in
         /usr|/System*) ;;
         *)
	  am_cv_python_pythondir=$PYTHON_PREFIX/lib/python$PYTHON_VERSION/site-packages
	  ;;
       esac
       ;;
     esac
    ])
  AC_SUBST([pythondir], [$am_cv_python_pythondir])

  dnl pkgpythondir -- $PACKAGE directory under pythondir.  Was
  dnl   PYTHON_SITE_PACKAGE in previous betas, but this naming is
  dnl   more consistent with the rest of automake.

  AC_SUBST([pkgpythondir], [\${pythondir}/$PACKAGE])

  dnl pyexecdir -- directory for installing python extension modules
  dnl   (shared libraries)
  dnl Query distutils for this directory.
  AC_CACHE_CHECK([for $am_display_PYTHON extension module directory],
    [am_cv_python_pyexecdir],
    [if test "x$exec_prefix" = xNONE
     then
       am_py_exec_prefix=$am_py_prefix
     else
       am_py_exec_prefix=$exec_prefix
     fi
     am_cv_python_pyexecdir=`$PYTHON -c "
$am_python_setup_sysconfig
if can_use_sysconfig:
    sitedir = sysconfig.get_path('platlib', vars={'platbase':'$am_py_prefix'})
else:
    from distutils import sysconfig
    sitedir = sysconfig.get_python_lib(1, 0, prefix='$am_py_prefix')
sys.stdout.write(sitedir)"`
     case $am_cv_python_pyexecdir in
     $am_py_exec_prefix*)
       am__strip_prefix=`echo "$am_py_exec_prefix" | sed 's|.|.|g'`
       am_cv_python_pyexecdir=`echo "$am_cv_python_pyexecdir" | sed "s,^$am__strip_prefix,$PYTHON_EXEC_PREFIX,"`
       ;;
     *)
       case $am_py_exec_prefix in
         /usr|/System*) ;;
         *)
	   am_cv_python_pyexecdir=$PYTHON_EXEC_PREFIX/lib/python$PYTHON_VERSION/site-packages
	   ;;
       esac
       ;;
     esac
    ])
  AC_SUBST([pyexecdir], [$am_cv_python_pyexecdir])

  dnl pkgpyexecdir -- $(pyexecdir)/$(PACKAGE)

  AC_SUBST([pkgpyexecdir], [\${pyexecdir}/$PACKAGE])

  dnl Run any user-specified action.
  $2
  fi

])


# AM_PYTHON_CHECK_VERSION(PROG, VERSION, [ACTION-IF-TRUE], [ACTION-IF-FALSE])
# ---------------------------------------------------------------------------
# Run ACTION-IF-TRUE if the Python interpreter PROG has version >= VERSION.
# Run ACTION-IF-FALSE otherwise.
# This test uses sys.hexversion instead of the string equivalent (first
# word of sys.version), in order to cope with versions such as 2.2c1.
# This supports Python 2.0 or higher. (2.0 was released on October 16, 2000).
AC_DEFUN([AM_PYTHON_CHECK_VERSION],
 [prog="import sys
# split strings by '.' and convert to numeric.  Append some zeros
# because we need at least 4 digits for the hex conversion.
# map returns an iterator in Python 3.0 and a list in 2.x
minver = list(map(int, '$2'.split('.'))) + [[0, 0, 0]]
minverhex = 0
# xrange is not present in Python 3.0 and range returns an iterator
for i in list(range(0, 4)): minverhex = (minverhex << 8) + minver[[i]]
sys.exit(sys.hexversion < minverhex)"
  AS_IF([AM_RUN_LOG([$1 -c "$prog"])], [$3], [$4])])

# Copyright (C) 2001-2020 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.

# AM_RUN_LOG(COMMAND)
# -------------------
# Run COMMAND, save the exit status in ac_status, and log it.
# (This has been adapted from Autoconf's _AC_RUN_LOG macro.)
AC_DEFUN([AM_RUN_LOG],
[{ echo "$as_me:$LINENO: $1" >&AS_MESSAGE_LOG_FD
   ($1) >&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD
   ac_status=$?
   echo "$as_me:$LINENO: \$? = $ac_status" >&AS_MESSAGE_LOG_FD
   (exit $ac_status); }])