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-rw-r--r--m4/ax_cxx_compile_stdcxx.m4951
-rw-r--r--m4/ax_cxx_compile_stdcxx_11.m4165
-rw-r--r--m4/ax_pthread.m4614
3 files changed, 1269 insertions, 461 deletions
diff --git a/m4/ax_cxx_compile_stdcxx.m4 b/m4/ax_cxx_compile_stdcxx.m4
new file mode 100644
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--- /dev/null
+++ b/m4/ax_cxx_compile_stdcxx.m4
@@ -0,0 +1,951 @@
+# ===========================================================================
+# 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>
+# Copyright (c) 2019 Enji Cooper <yaneurabeya@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 11
+
+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 ~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
+
+#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
+
+]])
diff --git a/m4/ax_cxx_compile_stdcxx_11.m4 b/m4/ax_cxx_compile_stdcxx_11.m4
deleted file mode 100644
index a9a8f58..0000000
--- a/m4/ax_cxx_compile_stdcxx_11.m4
+++ /dev/null
@@ -1,165 +0,0 @@
-# ============================================================================
-# http://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 CXXFLAGS to enable support.
-#
-# The first 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 second argument, if specified 'mandatory' or if left unspecified,
-# indicates that baseline C++11 support 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_CXX11 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>
-#
-# 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
-
-m4_define([_AX_CXX_COMPILE_STDCXX_11_testbody], [[
- template <typename T>
- struct check
- {
- static_assert(sizeof(int) <= sizeof(T), "not big enough");
- };
-
- struct Base {
- virtual void f() {}
- };
- struct Child : public Base {
- virtual void f() override {}
- };
-
- typedef check<check<bool>> right_angle_brackets;
-
- int a;
- decltype(a) b;
-
- typedef check<int> check_type;
- check_type c;
- check_type&& cr = static_cast<check_type&&>(c);
-
- auto d = a;
- auto l = [](){};
- // Prevent Clang error: unused variable 'l' [-Werror,-Wunused-variable]
- struct use_l { use_l() { l(); } };
-
- // 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);
- }
- }
-]])
-
-AC_DEFUN([AX_CXX_COMPILE_STDCXX_11], [dnl
- m4_if([$1], [], [],
- [$1], [ext], [],
- [$1], [noext], [],
- [m4_fatal([invalid argument `$1' to AX_CXX_COMPILE_STDCXX_11])])dnl
- m4_if([$2], [], [ax_cxx_compile_cxx11_required=true],
- [$2], [mandatory], [ax_cxx_compile_cxx11_required=true],
- [$2], [optional], [ax_cxx_compile_cxx11_required=false],
- [m4_fatal([invalid second argument `$2' to AX_CXX_COMPILE_STDCXX_11])])
- AC_LANG_PUSH([C++])dnl
- ac_success=no
- AC_CACHE_CHECK(whether $CXX supports C++11 features by default,
- ax_cv_cxx_compile_cxx11,
- [AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_11_testbody])],
- [ax_cv_cxx_compile_cxx11=yes],
- [ax_cv_cxx_compile_cxx11=no])])
- if test x$ax_cv_cxx_compile_cxx11 = xyes; then
- ac_success=yes
- fi
-
- m4_if([$1], [noext], [], [dnl
- if test x$ac_success = xno; then
- for switch in -std=gnu++11 -std=gnu++0x; do
- cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx11_$switch])
- AC_CACHE_CHECK(whether $CXX supports C++11 features with $switch,
- $cachevar,
- [ac_save_CXXFLAGS="$CXXFLAGS"
- CXXFLAGS="$CXXFLAGS $switch"
- AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_11_testbody])],
- [eval $cachevar=yes],
- [eval $cachevar=no])
- CXXFLAGS="$ac_save_CXXFLAGS"])
- if eval test x\$$cachevar = xyes; then
- CXXFLAGS="$CXXFLAGS $switch"
- ac_success=yes
- break
- fi
- done
- fi])
-
- m4_if([$1], [ext], [], [dnl
- if test x$ac_success = xno; then
- for switch in -std=c++11 -std=c++0x; do
- cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx11_$switch])
- AC_CACHE_CHECK(whether $CXX supports C++11 features with $switch,
- $cachevar,
- [ac_save_CXXFLAGS="$CXXFLAGS"
- CXXFLAGS="$CXXFLAGS $switch"
- AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_11_testbody])],
- [eval $cachevar=yes],
- [eval $cachevar=no])
- CXXFLAGS="$ac_save_CXXFLAGS"])
- if eval test x\$$cachevar = xyes; then
- CXXFLAGS="$CXXFLAGS $switch"
- ac_success=yes
- break
- fi
- done
- fi])
- AC_LANG_POP([C++])
- if test x$ax_cxx_compile_cxx11_required = xtrue; then
- if test x$ac_success = xno; then
- AC_MSG_ERROR([*** A compiler with support for C++11 language features is required.])
- fi
- else
- if test x$ac_success = xno; then
- HAVE_CXX11=0
- AC_MSG_NOTICE([No compiler with C++11 support was found])
- else
- HAVE_CXX11=1
- AC_DEFINE(HAVE_CXX11,1,
- [define if the compiler supports basic C++11 syntax])
- fi
-
- AC_SUBST(HAVE_CXX11)
- fi
-])
diff --git a/m4/ax_pthread.m4 b/m4/ax_pthread.m4
index d218d1a..1598d07 100644
--- a/m4/ax_pthread.m4
+++ b/m4/ax_pthread.m4
@@ -1,5 +1,5 @@
# ===========================================================================
-# http://www.gnu.org/software/autoconf-archive/ax_pthread.html
+# https://www.gnu.org/software/autoconf-archive/ax_pthread.html
# ===========================================================================
#
# SYNOPSIS
@@ -55,6 +55,7 @@
#
# 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
@@ -67,7 +68,7 @@
# Public License for more details.
#
# You should have received a copy of the GNU General Public License along
-# with this program. If not, see <http://www.gnu.org/licenses/>.
+# 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
@@ -82,7 +83,7 @@
# modified version of the Autoconf Macro, you may extend this special
# exception to the GPL to apply to your modified version as well.
-#serial 22
+#serial 27
AU_ALIAS([ACX_PTHREAD], [AX_PTHREAD])
AC_DEFUN([AX_PTHREAD], [
@@ -100,22 +101,22 @@ ax_pthread_ok=no
# 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="$PTHREAD_CC"])
- CFLAGS="$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"
+ ax_pthread_save_CC="$CC"
+ ax_pthread_save_CFLAGS="$CFLAGS"
+ ax_pthread_save_LIBS="$LIBS"
+ AS_IF([test "x$PTHREAD_CC" != "x"], [CC="$PTHREAD_CC"])
+ CFLAGS="$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
@@ -123,10 +124,12 @@ fi
# (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 starting with a "-" are
-# C compiler flags, and other 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.
+# 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"
@@ -152,319 +155,338 @@ ax_pthread_flags="pthreads none -Kthread -pthread -pthreads -mthreads pthread --
case $host_os in
- freebsd*)
+ freebsd*)
- # -kthread: FreeBSD kernel threads (preferred to -pthread since SMP-able)
- # lthread: LinuxThreads port on FreeBSD (also preferred to -pthread)
+ # -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"
- ;;
+ ax_pthread_flags="-kthread lthread $ax_pthread_flags"
+ ;;
- hpux*)
+ hpux*)
- # From the cc(1) man page: "[-mt] Sets various -D flags to enable
- # multi-threading and also sets -lpthread."
+ # 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"
- ;;
+ ax_pthread_flags="-mt -pthread pthread $ax_pthread_flags"
+ ;;
- openedition*)
+ 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.)
+ # 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.])])
- ;;
+ 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*)
+ 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).
+ # 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,pthread pthread $ax_pthread_flags"
- ;;
+ 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 -pthreads $ax_pthread_flags"])
+ [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 $host_os in
- darwin* | hpux* | linux* | osf* | solaris*)
- ax_pthread_check_macro="_REENTRANT"
- ;;
+ darwin* | hpux* | linux* | osf* | solaris*)
+ ax_pthread_check_macro="_REENTRANT"
+ ;;
- aix* | freebsd*)
- ax_pthread_check_macro="_THREAD_SAFE"
- ;;
+ aix*)
+ ax_pthread_check_macro="_THREAD_SAFE"
+ ;;
- *)
- ax_pthread_check_macro="--"
- ;;
+ *)
+ ax_pthread_check_macro="--"
+ ;;
esac
AS_IF([test "x$ax_pthread_check_macro" = "x--"],
[ax_pthread_check_cond=0],
[ax_pthread_check_cond="!defined($ax_pthread_check_macro)"])
-# 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="$ax_cv_PTHREAD_CLANG"
+if test "x$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
-ax_pthread_clang_warning=no
# 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.)
-
- PTHREAD_CFLAGS="-pthread"
- PTHREAD_LIBS=
-
- ax_pthread_ok=yes
-
- # 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
+ # 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 # $ax_pthread_clang = yes
-if test "x$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])
- ;;
-
- -mt,pthread)
- AC_MSG_CHECKING([whether pthreads work with -mt -lpthread])
- PTHREAD_CFLAGS="-mt"
- PTHREAD_LIBS="-lpthread"
- ;;
-
- -*)
- 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 routine(void *a) { a = 0; }
- 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
# 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 $PTHREAD_CFLAGS"
- ax_pthread_special_flags_added=yes])
-
- AC_CACHE_CHECK([for PTHREAD_PRIO_INHERIT],
- [ax_cv_PTHREAD_PRIO_INHERIT],
- [AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <pthread.h>]],
- [[int i = PTHREAD_PRIO_INHERIT;]])],
- [ax_cv_PTHREAD_PRIO_INHERIT=yes],
- [ax_cv_PTHREAD_PRIO_INHERIT=no])
- ])
- AS_IF([test "x$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="${CC}_r"])],
- [AC_CHECK_PROGS([PTHREAD_CC],[${CC}_r],[$CC])])])
- ;;
- esac
- fi
+ ax_pthread_save_CFLAGS="$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="${CC}_r"])],
+ [AC_CHECK_PROGS([PTHREAD_CC],[${CC}_r],[$CC])])])
+ ;;
+ esac
+ fi
fi
test -n "$PTHREAD_CC" || PTHREAD_CC="$CC"
@@ -475,11 +497,11 @@ AC_SUBST([PTHREAD_CC])
# Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND:
if test "x$ax_pthread_ok" = "xyes"; then
- ifelse([$1],,[AC_DEFINE([HAVE_PTHREAD],[1],[Define if you have POSIX threads libraries and header files.])],[$1])
- :
+ ifelse([$1],,[AC_DEFINE([HAVE_PTHREAD],[1],[Define if you have POSIX threads libraries and header files.])],[$1])
+ :
else
- ax_pthread_ok=no
- $2
+ ax_pthread_ok=no
+ $2
fi
AC_LANG_POP
])dnl AX_PTHREAD