From: Simon Marchi Date: Fri, 3 Sep 2021 21:31:28 +0000 (-0400) Subject: Add mandatory C++ compiler build dependency X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=c30417c11fcaf0406c4cfb3a09373c848a86e291;p=lttng-tools.git Add mandatory C++ compiler build dependency This change is in preparation of converting some internal code to C++. - Add ax_cxx_compile_stdcxx.m4, which provides AX_CXX_COMPILE_STDCXX, a macro to find a C++ compiler matching certain characteristics. - Find which warning flags work for the C++ compiler (certain warning flags may be C or C++ specific). - Do a bit of reorganizing to group all C compiler things together, all C++ compiler things together. Change-Id: I35a16996fa9ba1fbbb040f7fa5f826e6bc95ea29 Signed-off-by: Michael Jeanson Signed-off-by: Simon Marchi Signed-off-by: Jérémie Galarneau --- diff --git a/configure.ac b/configure.ac index 496c55ad1..ea327f9b8 100644 --- a/configure.ac +++ b/configure.ac @@ -15,47 +15,113 @@ AM_MAINTAINER_MODE([enable]) # Enable silent rules if available (Introduced in AM 1.11) m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])]) -# Checks for C compiler -AC_USE_SYSTEM_EXTENSIONS -AC_SYS_LARGEFILE + +## ## +## C compiler checks ## +## ## + +# Choose the C compiler AC_PROG_CC # AC_PROG_CC_STDC was merged in AC_PROG_CC in autoconf 2.70 m4_version_prereq([2.70], [], [AC_PROG_CC_STDC]) -AC_PROG_CXX -RW_PROG_CXX_WORKS -AM_CONDITIONAL([CXX_WORKS], [test "x$rw_cv_prog_cxx_works" = "xyes"]) -# Detect warning flags supported by the compiler, append them to WARN_CFLAGS. +# Make sure the C compiler supports C99 +AS_IF([test "$ac_cv_prog_cc_c99" = "no"], [AC_MSG_ERROR([The compiler does not support C99])]) + +# Enable available system extensions and LFS support +AC_USE_SYSTEM_EXTENSIONS +AC_SYS_LARGEFILE + +# Make sure the C compiler supports __attribute__ +AX_C___ATTRIBUTE__ +AS_IF([test "x$ax_cv___attribute__" != "xyes"], + [AC_MSG_ERROR([The compiler does not support __attribute__ extensions])]) + +# Make sure we have pthread support +AX_PTHREAD([], [AC_MSG_ERROR([Could not configure pthread support])]) + +# Checks for typedefs, structures, and compiler characteristics. +AC_C_INLINE +AC_TYPE_INT32_T +AC_TYPE_INT64_T +AC_TYPE_MODE_T +AC_TYPE_OFF_T +AC_TYPE_PID_T +AC_TYPE_SIZE_T +AC_TYPE_SSIZE_T +AC_TYPE_UID_T +AC_TYPE_UINT16_T +AC_TYPE_UINT32_T +AC_TYPE_UINT64_T +AC_TYPE_UINT8_T + +# Detect warning flags supported by the C and C++ compilers and append them to +# WARN_CFLAGS and WARN_CXXFLAGS. +m4_define([WARN_FLAGS_LIST], [ dnl + -Wall dnl + dnl We currently get this warning when building with Clang: + dnl + dnl /usr/include/setjmp.h:54:12: error: declaration of built-in function '__sigsetjmp' requires the declaration of the 'jmp_buf' type, commonly provided in the header . [-Werror,-Wincomplete-setjmp-declaration] + dnl extern int __sigsetjmp (struct __jmp_buf_tag __env[1], int __savemask) __THROWNL; + dnl ^ + -Wno-incomplete-setjmp-declaration dnl + -Wdiscarded-qualifiers dnl + -Wmissing-declarations dnl + -Wmissing-prototypes dnl + -Wmissing-parameter-type dnl + -Wshadow dnl + -Wno-gnu-folding-constant dnl +]) + +# Pass -Werror as an extra flag during the test: this is needed to make the +# -Wunknown-warning-option diagnostic fatal with clang. +AC_LANG_PUSH([C]) +AX_APPEND_COMPILE_FLAGS([WARN_FLAGS_LIST], [WARN_CFLAGS], [-Werror]) +AC_LANG_POP([C]) + +# The test used in AX_APPEND_COMPILE_FLAGS, generated using AC_LANG_PROGRAM, is +# written in such a way that it triggers warnings with the following warning +# flags. So they would always end up disabled if we put them there, because +# the test program would not build. # +# Enable them here unconditionally. They are supported by GCC >= 4.8 and by +# Clang >= 3.3 (required by the project) and are only valid for C code. +WARN_CFLAGS="${WARN_CFLAGS} -Wold-style-definition -Wstrict-prototypes" + +# Disable 'strict aliasing' if the C compiler supports it. +AC_LANG_PUSH([C]) +AX_APPEND_COMPILE_FLAGS([-fno-strict-aliasing], [OPT_CFLAGS], [-Werror]) +AC_LANG_POP([C]) + + +## ## +## C++ compiler checks ## +## ## + +# Find a C++11 compiler with GNU extensions (-std=gnu++11) +AX_CXX_COMPILE_STDCXX([11], [ext], [mandatory]) + # Pass -Werror as an extra flag during the test: this is needed to make the # -Wunknown-warning-option diagnostic fatal with clang. -AX_APPEND_COMPILE_FLAGS([ dnl - -Wall dnl - dnl We currently get this warning when building with Clang: - dnl - dnl /usr/include/setjmp.h:54:12: error: declaration of built-in function '__sigsetjmp' requires the declaration of the 'jmp_buf' type, commonly provided in the header . [-Werror,-Wincomplete-setjmp-declaration] - dnl extern int __sigsetjmp (struct __jmp_buf_tag __env[1], int __savemask) __THROWNL; - dnl ^ - -Wno-incomplete-setjmp-declaration dnl - -Wdiscarded-qualifiers dnl - -Wmissing-declarations dnl - -Wmissing-prototypes dnl - -Wmissing-parameter-type dnl - -Wold-style-definition dnl - -Wstrict-prototypes dnl - -Wshadow dnl - -Wno-gnu-folding-constant dnl - ], - [WARN_CFLAGS], - [-Werror]) - -# When given, add -Werror to WARN_CFLAGS. -AC_ARG_ENABLE([Werror], - [AS_HELP_STRING([--enable-Werror], [Treat compiler warnings as errors.])] -) -AS_IF([test "x$enable_Werror" = "xyes"], - [WARN_CFLAGS="${WARN_CFLAGS} -Werror"] -) +AC_LANG_PUSH([C++]) +AX_APPEND_COMPILE_FLAGS([WARN_FLAGS_LIST], [WARN_CXXFLAGS], [-Werror]) +AC_LANG_POP([C++]) + +# Disable 'strict aliasing' if the C++ compiler supports it. +AC_LANG_PUSH([C++]) +AX_APPEND_COMPILE_FLAGS([-fno-strict-aliasing], [OPT_CXXFLAGS], [-Werror]) +AC_LANG_POP([C++]) + + +# When given, add -Werror to WARN_CFLAGS and WARN_CXXFLAGS. +AC_ARG_ENABLE([Werror],[ + AS_HELP_STRING([--enable-Werror], [Treat compiler warnings as errors.]) +]) + +AS_IF([test "x$enable_Werror" = "xyes"], [ + WARN_CFLAGS="${WARN_CFLAGS} -Werror" + WARN_CXXFLAGS="${WARN_CXXFLAGS} -Werror" +]) # Checks for programs. AC_PROG_GREP @@ -127,27 +193,6 @@ detection. AM_CONDITIONAL([HAVE_FLEX], [test "x$have_flex" = "xyes"]) -# Checks for typedefs, structures, and compiler characteristics. -AC_C_INLINE -AC_TYPE_INT32_T -AC_TYPE_INT64_T -AC_TYPE_MODE_T -AC_TYPE_OFF_T -AC_TYPE_PID_T -AC_TYPE_SIZE_T -AC_TYPE_SSIZE_T -AC_TYPE_UID_T -AC_TYPE_UINT16_T -AC_TYPE_UINT32_T -AC_TYPE_UINT64_T -AC_TYPE_UINT8_T - -AX_C___ATTRIBUTE__ -AS_IF([test "x$ax_cv___attribute__" = "xyes"], - [:], - [AC_MSG_ERROR([The compiler does not support __attribute__ extensions])]) - -AX_PTHREAD(,[AC_MSG_ERROR([Could not configure pthreads support])]) # Check if linker has the -no-pie option. AX_CHECK_LINK_FLAG([-no-pie], [linker_have_no_pie_option=yes]) @@ -1037,9 +1082,12 @@ AM_CONDITIONAL([BUILD_LIB_SESSIOND_COMM], [test x$build_lib_sessiond_comm = xyes AM_CONDITIONAL([BUILD_LIB_TESTPOINT], [test x$build_lib_testpoint = xyes]) AM_CONDITIONAL([BUILD_LIB_UST_CONSUMER], [test x$build_lib_ust_consumer = xyes]) -AM_CFLAGS="${WARN_CFLAGS} -fno-strict-aliasing $PTHREAD_CFLAGS" +AM_CFLAGS="$OPT_CFLAGS $WARN_CFLAGS $PTHREAD_CFLAGS" AC_SUBST(AM_CFLAGS) +AM_CXXFLAGS="$OPT_CXXFLAGS $WARN_CXXFLAGS $PTHREAD_CFLAGS" +AC_SUBST(AM_CXXFLAGS) + # This is set even though it is empty, so Makefiles can do "AM_LDFLAGS += ...". AM_LDFLAGS="" AC_SUBST(AM_LDFLAGS) diff --git a/m4/ax_cxx_compile_stdcxx.m4 b/m4/ax_cxx_compile_stdcxx.m4 new file mode 100644 index 000000000..9413da624 --- /dev/null +++ b/m4/ax_cxx_compile_stdcxx.m4 @@ -0,0 +1,962 @@ +# =========================================================================== +# https://www.gnu.org/software/autoconf-archive/ax_cxx_compile_stdcxx.html +# =========================================================================== +# +# SYNOPSIS +# +# AX_CXX_COMPILE_STDCXX(VERSION, [ext|noext], [mandatory|optional]) +# +# DESCRIPTION +# +# Check for baseline language coverage in the compiler for the specified +# version of the C++ standard. If necessary, add switches to CXX and +# CXXCPP to enable support. VERSION may be '11' (for the C++11 standard) +# or '14' (for the C++14 standard). +# +# The second argument, if specified, indicates whether you insist on an +# extended mode (e.g. -std=gnu++11) or a strict conformance mode (e.g. +# -std=c++11). If neither is specified, you get whatever works, with +# preference for no added switch, and then for an extended mode. +# +# The third argument, if specified 'mandatory' or if left unspecified, +# indicates that baseline support for the specified C++ standard is +# required and that the macro should error out if no mode with that +# support is found. If specified 'optional', then configuration proceeds +# regardless, after defining HAVE_CXX${VERSION} if and only if a +# supporting mode is found. +# +# LICENSE +# +# Copyright (c) 2008 Benjamin Kosnik +# Copyright (c) 2012 Zack Weinberg +# Copyright (c) 2013 Roy Stogner +# Copyright (c) 2014, 2015 Google Inc.; contributed by Alexey Sokolov +# Copyright (c) 2015 Paul Norman +# Copyright (c) 2015 Moritz Klammler +# Copyright (c) 2016, 2018 Krzesimir Nowak +# Copyright (c) 2019 Enji Cooper +# Copyright (c) 2020 Jason Merrill +# +# 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 12 + +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], [], [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 +) + +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 + 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 single_type; + typedef check> double_type; + typedef check>> triple_type; + typedef check>>> 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 + { + 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::value == true, ""); + static_assert(is_same::value == false, ""); + static_assert(is_same::value == false, ""); + auto ac = c; + auto av = v; + auto sumi = ac + av + 'x'; + auto sumf = ac + av + 1.0; + static_assert(is_same::value == true, ""); + static_assert(is_same::value == true, ""); + static_assert(is_same::value == true, ""); + static_assert(is_same::value == false, ""); + static_assert(is_same::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 + struct sum; + + template + struct sum + { + static constexpr auto value = N0 + sum::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 + using member = typename T::member_type; + + template + void func(...) {} + + template + void func(member*) {} + + void test(); + + void test() { func(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 + { + static constexpr auto value = true; + }; + + int + test() + { + auto x = 0; + static_assert(is_same::value, ""); + static_assert(is_same::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 +#include +#include + +namespace cxx17 +{ + + namespace test_constexpr_lambdas + { + + constexpr int foo = [](){return 42;}(); + + } + + namespace test::nested_namespace::definitions + { + + } + + namespace test_fold_expression + { + + template + int multiply(Args... args) + { + return (args * ... * 1); + } + + template + 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, decltype(foo)>::value); + static_assert(std::is_same::value); + } + + namespace test_typename_in_template_template_parameter + { + + template 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 + 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 + 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 + struct B + {}; + + B<5> b1; + B<'a'> b2; + + } + + namespace test_structured_bindings + { + + int arr[2] = { 1, 2 }; + std::pair pr = { 1, 2 }; + + auto f1() -> int(&)[2] + { + return arr; + } + + auto f2() -> std::pair& + { + 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 + Bad + f(T*, T*); + + template + Good + f(T1*, T2*); + + static_assert (std::is_same_v); + + } + + namespace test_inline_variables + { + + template void f(T) + {} + + template 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/rw_prog_cxx_works.m4 b/m4/rw_prog_cxx_works.m4 deleted file mode 100644 index f3d6bde6b..000000000 --- a/m4/rw_prog_cxx_works.m4 +++ /dev/null @@ -1,50 +0,0 @@ -# SYNOPSIS -# -# RW_PROG_CXX_WORKS -# -# DESCRIPTION -# -# RW_PROG_CXX_WORKS checks whether the C++ compiler works. -# -# There's a bit of oversight in autoconf that will set the C++ compiler to -# g++ if no compiler is found, even if g++ is not present! So we need an -# extra test to make sure that the compiler works. -# -# LICENSE -# -# 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 1 - -AC_DEFUN([RW_PROG_CXX_WORKS], [ -AC_REQUIRE([AC_PROG_CXX]) -AC_CACHE_CHECK([whether the C++ compiler works], - [rw_cv_prog_cxx_works], - [AC_LANG_PUSH([C++]) - - AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])], [ - check_cxx_designated_initializers=yes - ], [ - rw_cv_prog_cxx_works=no - ]) - - AS_IF([test "x$check_cxx_designated_initializers" = "xyes"], [ - AC_COMPILE_IFELSE([AC_LANG_SOURCE([[ - struct foo { int a; int b; }; - void fct(void) - { - struct foo f = { .a = 0, .b = 1 }; - } - ]])], [ - rw_cv_prog_cxx_works=yes - ], [ - rw_cv_prog_cxx_works=no - ]) - ]) - - AC_LANG_POP([C++]) -]) -]) diff --git a/tests/utils/testapp/Makefile.am b/tests/utils/testapp/Makefile.am index dcb83d2d9..5b3805c6b 100644 --- a/tests/utils/testapp/Makefile.am +++ b/tests/utils/testapp/Makefile.am @@ -7,11 +7,8 @@ SUBDIRS = \ gen-ust-nevents \ gen-ust-nevents-str \ gen-ust-tracef \ - userspace-probe-elf-binary - -if CXX_WORKS -SUBDIRS += userspace-probe-elf-cxx-binary -endif # CXX_WORKS + userspace-probe-elf-binary \ + userspace-probe-elf-cxx-binary if TEST_SDT_UPROBE SUBDIRS += userspace-probe-sdt-binary diff --git a/tests/utils/testapp/userspace-probe-elf-cxx-binary/userspace-probe-elf-cxx-binary.cpp b/tests/utils/testapp/userspace-probe-elf-cxx-binary/userspace-probe-elf-cxx-binary.cpp index 6b30717ae..ab0f24144 100644 --- a/tests/utils/testapp/userspace-probe-elf-cxx-binary/userspace-probe-elf-cxx-binary.cpp +++ b/tests/utils/testapp/userspace-probe-elf-cxx-binary/userspace-probe-elf-cxx-binary.cpp @@ -8,7 +8,9 @@ #include "test_class.h" volatile int not_a_function = 0; -void __attribute__ ((noinline)) test_cxx_function() + +void test_cxx_function() __attribute__ ((noinline)); +void test_cxx_function() { not_a_function += 1; }