cpp,qt: Remove C++ and Qt bindings

* README: Update.
* configure.ac: Remove checks, variables and file generations related to
the C++/Qt bindings. Remove cpp and qt* from available_languages and
default_languages.
* lang/Makefile.am (DIST_SUBDIRS): Remove cpp and qt.
* lang/cpp, lang/qt: Remove.
* m4/ax_check_compile_flag.m4, m4/ax_cxx_compile_stdcxx.m4,
m4/ax_gcc_func_attribute.m4, m4/pkg.m4, m4/qt5.m4, m4/qt6.m4: Remove.
--

The C++ and Qt bindings have been moved to separate Git repositories:
gpgmepp and gpgmeqt.

GnuPG-bug-id: 7262

6 files changed, 0 insertions, 1642 deletions

diff --git a/m4/ax_check_compile_flag.m4 b/m4/ax_check_compile_flag.m4
deleted file mode 100644
index bd753b34..00000000
--- a/m4/ax_check_compile_flag.m4
+++ /dev/null
@@ -1,53 +0,0 @@
-# ===========================================================================
-#  https://www.gnu.org/software/autoconf-archive/ax_check_compile_flag.html
-# ===========================================================================
-#
-# SYNOPSIS
-#
-#   AX_CHECK_COMPILE_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT])
-#
-# DESCRIPTION
-#
-#   Check whether the given FLAG works with the current language's compiler
-#   or gives an error.  (Warnings, however, are ignored)
-#
-#   ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on
-#   success/failure.
-#
-#   If EXTRA-FLAGS is defined, it is added to the current language's default
-#   flags (e.g. CFLAGS) when the check is done.  The check is thus made with
-#   the flags: "CFLAGS EXTRA-FLAGS FLAG".  This can for example be used to
-#   force the compiler to issue an error when a bad flag is given.
-#
-#   INPUT gives an alternative input source to AC_COMPILE_IFELSE.
-#
-#   NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this
-#   macro in sync with AX_CHECK_{PREPROC,LINK}_FLAG.
-#
-# LICENSE
-#
-#   Copyright (c) 2008 Guido U. Draheim <[email protected]>
-#   Copyright (c) 2011 Maarten Bosmans <[email protected]>
-#
-#   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 6
-
-AC_DEFUN([AX_CHECK_COMPILE_FLAG],
-[AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_IF
-AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_[]_AC_LANG_ABBREV[]flags_$4_$1])dnl
-AC_CACHE_CHECK([whether _AC_LANG compiler accepts $1], CACHEVAR, [
-  ax_check_save_flags=$[]_AC_LANG_PREFIX[]FLAGS
-  _AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $4 $1"
-  AC_COMPILE_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])],
-    [AS_VAR_SET(CACHEVAR,[yes])],
-    [AS_VAR_SET(CACHEVAR,[no])])
-  _AC_LANG_PREFIX[]FLAGS=$ax_check_save_flags])
-AS_VAR_IF(CACHEVAR,yes,
-  [m4_default([$2], :)],
-  [m4_default([$3], :)])
-AS_VAR_POPDEF([CACHEVAR])dnl
-])dnl AX_CHECK_COMPILE_FLAGS
diff --git a/m4/ax_cxx_compile_stdcxx.m4 b/m4/ax_cxx_compile_stdcxx.m4
deleted file mode 100644
index a3d964c6..00000000
--- a/m4/ax_cxx_compile_stdcxx.m4
+++ /dev/null
@@ -1,1009 +0,0 @@
-# ===========================================================================
-#  https://www.gnu.org/software/autoconf-archive/ax_cxx_compile_stdcxx.html
-# ===========================================================================
-#
-# SYNOPSIS
-#
-#   AX_CXX_COMPILE_STDCXX(VERSION, [ext|noext], [mandatory|optional])
-#
-# DESCRIPTION
-#
-#   Check for baseline language coverage in the compiler for the specified
-#   version of the C++ standard.  If necessary, add switches to CXX and
-#   CXXCPP to enable support.  VERSION may be '11', '14', '17', or '20' for
-#   the respective C++ standard version.
-#
-#   The second argument, if specified, indicates whether you insist on an
-#   extended mode (e.g. -std=gnu++11) or a strict conformance mode (e.g.
-#   -std=c++11).  If neither is specified, you get whatever works, with
-#   preference for no added switch, and then for an extended mode.
-#
-#   The third argument, if specified 'mandatory' or if left unspecified,
-#   indicates that baseline support for the specified C++ standard is
-#   required and that the macro should error out if no mode with that
-#   support is found.  If specified 'optional', then configuration proceeds
-#   regardless, after defining HAVE_CXX${VERSION} if and only if a
-#   supporting mode is found.
-#
-# LICENSE
-#
-#   Copyright (c) 2008 Benjamin Kosnik <[email protected]>
-#   Copyright (c) 2012 Zack Weinberg <[email protected]>
-#   Copyright (c) 2013 Roy Stogner <[email protected]>
-#   Copyright (c) 2014, 2015 Google Inc.; contributed by Alexey Sokolov <[email protected]>
-#   Copyright (c) 2015 Paul Norman <[email protected]>
-#   Copyright (c) 2015 Moritz Klammler <[email protected]>
-#   Copyright (c) 2016, 2018 Krzesimir Nowak <[email protected]>
-#   Copyright (c) 2019 Enji Cooper <[email protected]>
-#   Copyright (c) 2020 Jason Merrill <[email protected]>
-#   Copyright (c) 2021 Jörn Heusipp <[email protected]>
-#
-#   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 15
-
-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"],
-        [$1], [20], [ax_cxx_compile_alternatives="20"],
-        [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], [], [dnl
-    AC_CACHE_CHECK(whether $CXX supports C++$1 features by default,
-		   ax_cv_cxx_compile_cxx$1,
-      [AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_testbody_$1])],
-        [ax_cv_cxx_compile_cxx$1=yes],
-        [ax_cv_cxx_compile_cxx$1=no])])
-    if test x$ax_cv_cxx_compile_cxx$1 = xyes; then
-      ac_success=yes
-    fi])
-
-  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
-)
-
-dnl  Test body for checking C++17 support
-
-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  Test body for checking C++20 support
-
-m4_define([_AX_CXX_COMPILE_STDCXX_testbody_20],
-  _AX_CXX_COMPILE_STDCXX_testbody_new_in_11
-  _AX_CXX_COMPILE_STDCXX_testbody_new_in_14
-  _AX_CXX_COMPILE_STDCXX_testbody_new_in_17
-  _AX_CXX_COMPILE_STDCXX_testbody_new_in_20
-)
-
-
-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"
-
-// MSVC always sets __cplusplus to 199711L in older versions; newer versions
-// only set it correctly if /Zc:__cplusplus is specified as well as a
-// /std:c++NN switch:
-// https://devblogs.microsoft.com/cppblog/msvc-now-correctly-reports-__cplusplus/
-#elif __cplusplus < 201103L && !defined _MSC_VER
-
-#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 ~Base() {}
-      virtual void f() {}
-    };
-
-    struct Derived : public Base
-    {
-      virtual ~Derived() override {}
-      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 && !defined _MSC_VER
-
-#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 && !defined _MSC_VER
-
-#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 && !defined _MSC_VER
-
-]])
-
-
-dnl  Tests for new features in C++20
-
-m4_define([_AX_CXX_COMPILE_STDCXX_testbody_new_in_20], [[
-
-#ifndef __cplusplus
-
-#error "This is not a C++ compiler"
-
-#elif __cplusplus < 202002L && !defined _MSC_VER
-
-#error "This is not a C++20 compiler"
-
-#else
-
-#include <version>
-
-namespace cxx20
-{
-
-// As C++20 supports feature test macros in the standard, there is no
-// immediate need to actually test for feature availability on the
-// Autoconf side.
-
-}  // namespace cxx20
-
-#endif  // __cplusplus < 202002L && !defined _MSC_VER
-
-]])
diff --git a/m4/ax_gcc_func_attribute.m4 b/m4/ax_gcc_func_attribute.m4
deleted file mode 100644
index fa4e089d..00000000
--- a/m4/ax_gcc_func_attribute.m4
+++ /dev/null
@@ -1,242 +0,0 @@
-# ===========================================================================
-#  https://www.gnu.org/software/autoconf-archive/ax_gcc_func_attribute.html
-# ===========================================================================
-#
-# SYNOPSIS
-#
-#   AX_GCC_FUNC_ATTRIBUTE(ATTRIBUTE)
-#
-# DESCRIPTION
-#
-#   This macro checks if the compiler supports one of GCC's function
-#   attributes; many other compilers also provide function attributes with
-#   the same syntax. Compiler warnings are used to detect supported
-#   attributes as unsupported ones are ignored by default so quieting
-#   warnings when using this macro will yield false positives.
-#
-#   The ATTRIBUTE parameter holds the name of the attribute to be checked.
-#
-#   If ATTRIBUTE is supported define HAVE_FUNC_ATTRIBUTE_<ATTRIBUTE>.
-#
-#   The macro caches its result in the ax_cv_have_func_attribute_<attribute>
-#   variable.
-#
-#   The macro currently supports the following function attributes:
-#
-#    alias
-#    aligned
-#    alloc_size
-#    always_inline
-#    artificial
-#    cold
-#    const
-#    constructor
-#    constructor_priority for constructor attribute with priority
-#    deprecated
-#    destructor
-#    dllexport
-#    dllimport
-#    error
-#    externally_visible
-#    fallthrough
-#    flatten
-#    format
-#    format_arg
-#    gnu_format
-#    gnu_inline
-#    hot
-#    ifunc
-#    leaf
-#    malloc
-#    noclone
-#    noinline
-#    nonnull
-#    noreturn
-#    nothrow
-#    optimize
-#    pure
-#    sentinel
-#    sentinel_position
-#    unused
-#    used
-#    visibility
-#    warning
-#    warn_unused_result
-#    weak
-#    weakref
-#
-#   Unsupported function attributes will be tested with a prototype
-#   returning an int and not accepting any arguments and the result of the
-#   check might be wrong or meaningless so use with care.
-#
-# LICENSE
-#
-#   Copyright (c) 2013 Gabriele Svelto <[email protected]>
-#
-#   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 13
-
-AC_DEFUN([AX_GCC_FUNC_ATTRIBUTE], [
-    AS_VAR_PUSHDEF([ac_var], [ax_cv_have_func_attribute_$1])
-
-    AC_CACHE_CHECK([for __attribute__(($1))], [ac_var], [
-        AC_LINK_IFELSE([AC_LANG_PROGRAM([
-            m4_case([$1],
-                [alias], [
-                    int foo( void ) { return 0; }
-                    int bar( void ) __attribute__(($1("foo")));
-                ],
-                [aligned], [
-                    int foo( void ) __attribute__(($1(32)));
-                ],
-                [alloc_size], [
-                    void *foo(int a) __attribute__(($1(1)));
-                ],
-                [always_inline], [
-                    inline __attribute__(($1)) int foo( void ) { return 0; }
-                ],
-                [artificial], [
-                    inline __attribute__(($1)) int foo( void ) { return 0; }
-                ],
-                [cold], [
-                    int foo( void ) __attribute__(($1));
-                ],
-                [const], [
-                    int foo( void ) __attribute__(($1));
-                ],
-                [constructor_priority], [
-                    int foo( void ) __attribute__((__constructor__(65535/2)));
-                ],
-                [constructor], [
-                    int foo( void ) __attribute__(($1));
-                ],
-                [deprecated], [
-                    int foo( void ) __attribute__(($1("")));
-                ],
-                [destructor], [
-                    int foo( void ) __attribute__(($1));
-                ],
-                [dllexport], [
-                    __attribute__(($1)) int foo( void ) { return 0; }
-                ],
-                [dllimport], [
-                    int foo( void ) __attribute__(($1));
-                ],
-                [error], [
-                    int foo( void ) __attribute__(($1("")));
-                ],
-                [externally_visible], [
-                    int foo( void ) __attribute__(($1));
-                ],
-                [fallthrough], [
-                    void foo( int x ) {switch (x) { case 1: __attribute__(($1)); case 2: break ; }};
-                ],
-                [flatten], [
-                    int foo( void ) __attribute__(($1));
-                ],
-                [format], [
-                    int foo(const char *p, ...) __attribute__(($1(printf, 1, 2)));
-                ],
-                [gnu_format], [
-                    int foo(const char *p, ...) __attribute__((format(gnu_printf, 1, 2)));
-                ],
-                [format_arg], [
-                    char *foo(const char *p) __attribute__(($1(1)));
-                ],
-                [gnu_inline], [
-                    inline __attribute__(($1)) int foo( void ) { return 0; }
-                ],
-                [hot], [
-                    int foo( void ) __attribute__(($1));
-                ],
-                [ifunc], [
-                    int my_foo( void ) { return 0; }
-                    static int (*resolve_foo(void))(void) { return my_foo; }
-                    int foo( void ) __attribute__(($1("resolve_foo")));
-                ],
-                [leaf], [
-                    __attribute__(($1)) int foo( void ) { return 0; }
-                ],
-                [malloc], [
-                    void *foo( void ) __attribute__(($1));
-                ],
-                [noclone], [
-                    int foo( void ) __attribute__(($1));
-                ],
-                [noinline], [
-                    __attribute__(($1)) int foo( void ) { return 0; }
-                ],
-                [nonnull], [
-                    int foo(char *p) __attribute__(($1(1)));
-                ],
-                [noreturn], [
-                    void foo( void ) __attribute__(($1));
-                ],
-                [nothrow], [
-                    int foo( void ) __attribute__(($1));
-                ],
-                [optimize], [
-                    __attribute__(($1(3))) int foo( void ) { return 0; }
-                ],
-                [pure], [
-                    int foo( void ) __attribute__(($1));
-                ],
-                [sentinel], [
-                    int foo(void *p, ...) __attribute__(($1));
-                ],
-                [sentinel_position], [
-                    int foo(void *p, ...) __attribute__(($1(1)));
-                ],
-                [returns_nonnull], [
-                    void *foo( void ) __attribute__(($1));
-                ],
-                [unused], [
-                    int foo( void ) __attribute__(($1));
-                ],
-                [used], [
-                    int foo( void ) __attribute__(($1));
-                ],
-                [visibility], [
-                    int foo_def( void ) __attribute__(($1("default")));
-                    int foo_hid( void ) __attribute__(($1("hidden")));
-                    int foo_int( void ) __attribute__(($1("internal")));
-                    int foo_pro( void ) __attribute__(($1("protected")));
-                ],
-                [warning], [
-                    int foo( void ) __attribute__(($1("")));
-                ],
-                [warn_unused_result], [
-                    int foo( void ) __attribute__(($1));
-                ],
-                [weak], [
-                    int foo( void ) __attribute__(($1));
-                ],
-                [weakref], [
-                    static int foo( void ) { return 0; }
-                    static int bar( void ) __attribute__(($1("foo")));
-                ],
-                [
-                 m4_warn([syntax], [Unsupported attribute $1, the test may fail])
-                 int foo( void ) __attribute__(($1));
-                ]
-            )], [])
-            ],
-            dnl GCC doesn't exit with an error if an unknown attribute is
-            dnl provided but only outputs a warning, so accept the attribute
-            dnl only if no warning were issued.
-            [AS_IF([grep -- -Wattributes conftest.err],
-                [AS_VAR_SET([ac_var], [no])],
-                [AS_VAR_SET([ac_var], [yes])])],
-            [AS_VAR_SET([ac_var], [no])])
-    ])
-
-    AS_IF([test yes = AS_VAR_GET([ac_var])],
-        [AC_DEFINE_UNQUOTED(AS_TR_CPP(HAVE_FUNC_ATTRIBUTE_$1), 1,
-            [Define to 1 if the system has the `$1' function attribute])], [])
-
-    AS_VAR_POPDEF([ac_var])
-])
diff --git a/m4/pkg.m4 b/m4/pkg.m4
deleted file mode 100644
index 5865daf1..00000000
--- a/m4/pkg.m4
+++ /dev/null
@@ -1,157 +0,0 @@
-# pkg.m4 - Macros to locate and utilise pkg-config.            -*- Autoconf -*-
-#
-# Copyright © 2004 Scott James Remnant <[email protected]>.
-#
-# This program is free software; you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 2 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful, but
-# WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-# General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program; if not, write to the Free Software
-# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
-#
-# As a special exception to the GNU General Public License, if you
-# distribute this file as part of a program that contains a
-# configuration script generated by Autoconf, you may include it under
-# the same distribution terms that you use for the rest of that program.
-
-# PKG_PROG_PKG_CONFIG([MIN-VERSION])
-# ----------------------------------
-AC_DEFUN([PKG_PROG_PKG_CONFIG],
-[m4_pattern_forbid([^_?PKG_[A-Z_]+$])
-m4_pattern_allow([^PKG_CONFIG(_PATH)?$])
-AC_ARG_VAR([PKG_CONFIG], [path to pkg-config utility])dnl
-if test "x$ac_cv_env_PKG_CONFIG_set" != "xset"; then
-	AC_PATH_TOOL([PKG_CONFIG], [pkg-config])
-fi
-if test -n "$PKG_CONFIG"; then
-	_pkg_min_version=m4_default([$1], [0.9.0])
-	AC_MSG_CHECKING([pkg-config is at least version $_pkg_min_version])
-	if $PKG_CONFIG --atleast-pkgconfig-version $_pkg_min_version; then
-		AC_MSG_RESULT([yes])
-	else
-		AC_MSG_RESULT([no])
-		PKG_CONFIG=""
-	fi
-
-fi[]dnl
-])# PKG_PROG_PKG_CONFIG
-
-# PKG_CHECK_EXISTS(MODULES, [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND])
-#
-# Check to see whether a particular set of modules exists.  Similar
-# to PKG_CHECK_MODULES(), but does not set variables or print errors.
-#
-#
-# Similar to PKG_CHECK_MODULES, make sure that the first instance of
-# this or PKG_CHECK_MODULES is called, or make sure to call
-# PKG_CHECK_EXISTS manually
-# --------------------------------------------------------------
-AC_DEFUN([PKG_CHECK_EXISTS],
-[AC_REQUIRE([PKG_PROG_PKG_CONFIG])dnl
-if test -n "$PKG_CONFIG" && \
-    AC_RUN_LOG([$PKG_CONFIG --exists --print-errors "$1"]); then
-  m4_ifval([$2], [$2], [:])
-m4_ifvaln([$3], [else
-  $3])dnl
-fi])
-
-
-# _PKG_CONFIG([VARIABLE], [COMMAND], [MODULES])
-# ---------------------------------------------
-m4_define([_PKG_CONFIG],
-[if test -n "$PKG_CONFIG"; then
-    if test -n "$$1"; then
-        pkg_cv_[]$1="$$1"
-    else
-        PKG_CHECK_EXISTS([$3],
-                         [pkg_cv_[]$1=`$PKG_CONFIG --[]$2 "$3" 2>/dev/null`],
-			 [pkg_failed=yes])
-    fi
-else
-	pkg_failed=untried
-fi[]dnl
-])# _PKG_CONFIG
-
-# _PKG_SHORT_ERRORS_SUPPORTED
-# -----------------------------
-AC_DEFUN([_PKG_SHORT_ERRORS_SUPPORTED],
-[AC_REQUIRE([PKG_PROG_PKG_CONFIG])
-if $PKG_CONFIG --atleast-pkgconfig-version 0.20; then
-        _pkg_short_errors_supported=yes
-else
-        _pkg_short_errors_supported=no
-fi[]dnl
-])# _PKG_SHORT_ERRORS_SUPPORTED
-
-
-# PKG_CHECK_MODULES(VARIABLE-PREFIX, MODULES, [ACTION-IF-FOUND],
-# [ACTION-IF-NOT-FOUND])
-#
-#
-# Note that if there is a possibility the first call to
-# PKG_CHECK_MODULES might not happen, you should be sure to include an
-# explicit call to PKG_PROG_PKG_CONFIG in your configure.ac
-#
-#
-# --------------------------------------------------------------
-AC_DEFUN([PKG_CHECK_MODULES],
-[AC_REQUIRE([PKG_PROG_PKG_CONFIG])dnl
-AC_ARG_VAR([$1][_CFLAGS], [C compiler flags for $1, overriding pkg-config])dnl
-AC_ARG_VAR([$1][_LIBS], [linker flags for $1, overriding pkg-config])dnl
-
-pkg_failed=no
-AC_MSG_CHECKING([for $1])
-
-_PKG_CONFIG([$1][_CFLAGS], [cflags], [$2])
-_PKG_CONFIG([$1][_LIBS], [libs], [$2])
-
-m4_define([_PKG_TEXT], [Alternatively, you may set the environment variables $1[]_CFLAGS
-and $1[]_LIBS to avoid the need to call pkg-config.
-See the pkg-config man page for more details.])
-
-if test $pkg_failed = yes; then
-        _PKG_SHORT_ERRORS_SUPPORTED
-        if test $_pkg_short_errors_supported = yes; then
-	        $1[]_PKG_ERRORS=`$PKG_CONFIG --short-errors --errors-to-stdout --print-errors "$2"`
-        else
-	        $1[]_PKG_ERRORS=`$PKG_CONFIG --errors-to-stdout --print-errors "$2"`
-        fi
-	# Put the nasty error message in config.log where it belongs
-	echo "$$1[]_PKG_ERRORS" >&AS_MESSAGE_LOG_FD
-
-	ifelse([$4], , [AC_MSG_ERROR(dnl
-[Package requirements ($2) were not met:
-
-$$1_PKG_ERRORS
-
-Consider adjusting the PKG_CONFIG_PATH environment variable if you
-installed software in a non-standard prefix.
-
-_PKG_TEXT
-])],
-		[AC_MSG_RESULT([no])
-                $4])
-elif test $pkg_failed = untried; then
-	ifelse([$4], , [AC_MSG_FAILURE(dnl
-[The pkg-config script could not be found or is too old.  Make sure it
-is in your PATH or set the PKG_CONFIG environment variable to the full
-path to pkg-config.
-
-_PKG_TEXT
-
-To get pkg-config, see <https://www.freedesktop.org/software/pkgconfig>.])],
-		[$4])
-else
-	$1[]_CFLAGS=$pkg_cv_[]$1[]_CFLAGS
-	$1[]_LIBS=$pkg_cv_[]$1[]_LIBS
-        AC_MSG_RESULT([yes])
-	ifelse([$3], , :, [$3])
-fi[]dnl
-])# PKG_CHECK_MODULES
diff --git a/m4/qt5.m4 b/m4/qt5.m4
deleted file mode 100644
index cc453261..00000000
--- a/m4/qt5.m4
+++ /dev/null
@@ -1,83 +0,0 @@
-dnl qt5.m4
-dnl Copyright (C) 2016 Intevation GmbH
-dnl
-dnl This file is part of gpgme and is provided under the same license as gpgme
-
-dnl Autoconf macro to find Qt5
-dnl
-dnl sets GPGME_QT5_LIBS, GPGME_QT5_CFLAGS, and MOC5
-dnl
-dnl if QT5 was found have_qt5_libs is set to yes
-
-AC_DEFUN([FIND_QT5],
-[
-  have_qt5_libs="no";
-
-  PKG_CHECK_MODULES(GPGME_QT5,
-                    Qt5Core >= 5.0.0,
-                    [have_qt5_libs="yes"],
-                    [have_qt5_libs="no"])
-
-  PKG_CHECK_MODULES(GPGME_QT5TEST,
-                    Qt5Test >= 5.0.0,
-                    [have_qt5test_libs="yes"],
-                    [have_qt5test_libs="no"])
-
-  if ! test "$have_w32_system" = yes; then
-    if "$PKG_CONFIG" --variable qt_config Qt5Core | grep -q "reduce_relocations"; then
-      GPGME_QT5_CFLAGS="$GPGME_QT5_CFLAGS -fpic"
-    fi
-  fi
-  if test "$have_qt5_libs" = "yes"; then
-    AC_CHECK_TOOL(MOC5, moc)
-    AC_MSG_CHECKING([moc version])
-    mocversion=`$MOC5 -v 2>&1`
-    mocversiongrep=`echo $mocversion | grep -E "Qt 5|moc 5"`
-    if test x"$mocversiongrep" != x"$mocversion"; then
-      AC_MSG_RESULT([no])
-      # moc was not the qt5 one, try with moc-qt5
-      AC_CHECK_TOOL(MOC2, moc-qt5)
-      mocversion=`$MOC2 -v 2>&1`
-      mocversiongrep=`echo $mocversion | grep -E "Qt 5|moc-qt5 5|moc 5"`
-      if test x"$mocversiongrep" != x"$mocversion"; then
-        AC_CHECK_TOOL(QTCHOOSER, qtchooser)
-        qt5tooldir=`QT_SELECT=qt5 qtchooser -print-env | grep QTTOOLDIR | cut -d '=' -f 2 | cut -d \" -f 2`
-        mocversion=`$qt5tooldir/moc -v 2>&1`
-        mocversiongrep=`echo $mocversion | grep -E "Qt 5|moc 5"`
-        if test x"$mocversiongrep" != x"$mocversion"; then
-          # no valid moc found
-          have_qt5_libs="no";
-        else
-          MOC5=$qt5tooldir/moc
-        fi
-      else
-        MOC5=$MOC2
-      fi
-      unset MOC2
-    fi
-    AC_MSG_RESULT([$mocversion])
-  fi
-  if test "$have_qt5_libs" = "yes"; then
-    dnl Check that a binary can actually be build with this qt.
-    dnl pkg-config may be set up in a way that it looks also for libraries
-    dnl of the build system and not only for the host system. In that case
-    dnl we check here that we can actually compile / link a qt application
-    dnl for host.
-    OLDCPPFLAGS=$CPPFLAGS
-    CPPFLAGS=$GPGME_QT5_CFLAGS
-    OLDLIBS=$LIBS
-    LIBS=$GPGME_QT5_LIBS
-    AC_LANG_PUSH(C++)
-    AC_MSG_CHECKING([whether a simple qt program can be built])
-    AC_LINK_IFELSE([AC_LANG_SOURCE([
-    #include <QCoreApplication>
-    int main (int argc, char **argv) {
-    QCoreApplication app(argc, argv);
-    app.exec();
-    }])], [have_qt5_libs='yes'], [have_qt5_libs='no'])
-    AC_MSG_RESULT([$have_qt5_libs])
-    AC_LANG_POP()
-    CPPFLAGS=$OLDCPPFLAGS
-    LIBS=$OLDLIBS
-  fi
-])
diff --git a/m4/qt6.m4 b/m4/qt6.m4
deleted file mode 100644
index f62a9069..00000000
--- a/m4/qt6.m4
+++ /dev/null
@@ -1,98 +0,0 @@
-dnl qt6.m4
-dnl Copyright (C) 2016 Intevation GmbH
-dnl
-dnl This file is part of gpgme and is provided under the same license as gpgme
-
-dnl Autoconf macro to find Qt6
-dnl
-dnl sets GPGME_QT6_LIBS, GPGME_QT6_CFLAGS, and MOC6
-dnl
-dnl if QT6 was found have_qt6_libs is set to yes
-
-AC_DEFUN([FIND_QT6],
-[
-  have_qt6_libs="no";
-
-  PKG_CHECK_MODULES(GPGME_QT6,
-                    Qt6Core >= 6.4.0,
-                    [have_qt6_libs="yes"],
-                    [have_qt6_libs="no"])
-
-  PKG_CHECK_MODULES(GPGME_QT6TEST,
-                    Qt6Test >= 6.4.0,
-                    [have_qt6test_libs="yes"],
-                    [have_qt6test_libs="no"])
-
-  if test "$have_qt6_libs" = "yes"; then
-    # Qt6 moved moc to libexec
-    qt6libexecdir=$($PKG_CONFIG --variable=libexecdir 'Qt6Core >= 6.4.0')
-    AC_PATH_TOOL(MOC6, moc, [], [$qt6libexecdir])
-    if test -z "$MOC6"; then
-      AC_MSG_WARN([moc not found - Qt 6 binding will not be built.])
-      have_qt6_libs="no";
-    fi
-  fi
-
-  if test "$have_qt6_libs" = "yes"; then
-    if test "$have_w32_system" != yes; then
-      mkspecsdir=$($PKG_CONFIG --variable mkspecsdir Qt6Platform)
-      if test -z "$mkspecsdir"; then
-        AC_MSG_WARN([Failed to determine Qt's mkspecs directory. Cannot check its build configuration.])
-      fi
-    fi
-
-    # check if we need -fPIC
-    if test -z "$use_reduce_relocations" && test -n "$mkspecsdir"; then
-      AC_MSG_CHECKING([whether Qt was built with -fPIC])
-      if grep -q "QT_CONFIG .* reduce_relocations" $mkspecsdir/qconfig.pri; then
-        use_reduce_relocations="yes"
-      else
-        use_reduce_relocations="no"
-      fi
-      AC_MSG_RESULT([$use_reduce_relocations])
-    fi
-    if test "$use_reduce_relocations" = yes; then
-      GPGME_QT6_CFLAGS="$GPGME_QT6_CFLAGS -fPIC"
-    fi
-
-    # check if we need -mno-direct-extern-access
-    if test "$have_no_direct_extern_access" = yes; then
-      if test -z "$use_no_direct_extern_access" && test -n "$mkspecsdir"; then
-        AC_MSG_CHECKING([whether Qt was built with -mno-direct-extern-access])
-        if grep -q "QT_CONFIG .* no_direct_extern_access" $mkspecsdir/qconfig.pri; then
-          use_no_direct_extern_access="yes"
-        else
-          use_no_direct_extern_access="no"
-        fi
-        AC_MSG_RESULT([$use_no_direct_extern_access])
-      fi
-      if test "$use_no_direct_extern_access" = yes; then
-        GPGME_QT6_CFLAGS="$GPGME_QT6_CFLAGS -mno-direct-extern-access"
-      fi
-    fi
-
-    dnl Check that a binary can actually be build with this qt.
-    dnl pkg-config may be set up in a way that it looks also for libraries
-    dnl of the build system and not only for the host system. In that case
-    dnl we check here that we can actually compile / link a qt application
-    dnl for host.
-    OLDCPPFLAGS=$CPPFLAGS
-    OLDLIBS=$LIBS
-
-    CPPFLAGS=$GPGME_QT6_CFLAGS
-    LIBS=$GPGME_QT6_LIBS
-    AC_LANG_PUSH(C++)
-    AC_MSG_CHECKING([whether a simple Qt program can be built])
-    AC_LINK_IFELSE([AC_LANG_SOURCE([
-      #include <QCoreApplication>
-      int main (int argc, char **argv) {
-      QCoreApplication app(argc, argv);
-      app.exec();
-    }])], [have_qt6_libs='yes'], [have_qt6_libs='no'])
-    AC_MSG_RESULT([$have_qt6_libs])
-    AC_LANG_POP()
-
-    CPPFLAGS=$OLDCPPFLAGS
-    LIBS=$OLDLIBS
-  fi
-])